cleaning up the slant six head
- Thread starter 1930
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/6 Matt
30 Degrees Crooked
One more question along the lines of head porting for dummies. Can yall give reccomendations on the neccesary supplies, grinding bits and actual grinders themselves?
805moparkid
Slant and AFX Guy
well if you have a good compressor and live in warm weather go air, the straight from die grinders from HF work fine, if cold weather or no compressor go electric, don't know as much about this route but they work just as well.
As far as the bits you can buy them online, or thru places like Fastenal and Granger. I recommend the long tapered bit, 3/8" ball at a minimum, but the small ball like 1/8-3/16 and the straight bit come in handy to. Also it helps to have the short shank, about 2" and a longer one, like 4" or so for the slant head, some like the really long ones to.
I plan to do this work myself, I will be posting pictures along the way and asking for corrections suggestions as I go. I think you and I will have a pretty good understanding of the basics by the time I am done.
Tools and equipment are no issue for me but its easier for me to post pics which I will be doing after the next couple/few weeks.
Well, I may be the "Bill" that Ed alluded to earlier, and I am known on this forum as a motor-mouth (motor-keyboard?) because of my inability to contain myself, resulting in my penchant for writing long, rambling, wordy posts when I don't ACTUALLY know what I am talking about.
Apparently, that gets old to some people, because the management here got enough complaints about me that I was told by the higher-ups, to give it a rest, or face suspension of my account.
So, I did.
The powers that be have not sent me any more "directions" on how to manage my posting on here, so I must be doing better.
Anyway, I had stayed out of this thread because it dealt with something I wasn't particularly interested in, nor very knowledgeable about (so, I had nothing of interest, or value, to say.)
But, since Ed (805Moparkid) asked (well, sort of,) I decided to give it another shot.
To begin with, I am a virtual newbie at slant sixes, having owned my first one for only 4 years, Secondly, my interest is in forced induction as regards this engine, and I am equally-new at that, too. So, I am far from an expert. But, I have learned a lot in the past 4 years on FABO, from reading the posts, and on the "ORG." forum, so that, along with many years of conventional V8 hot rodding, and this has given me at least, some perspective.
To that end, I have come to some inescapable (for me) conclusions. I dug up an old post that illustrates some of them. This is from a few years ago, and is pertinent to this thread, I think.
To wit:
"As I immersed myself in the postings about /6 performance, and videos on You Tube of various /6-powered cars, I began to realize some things about these slanted little devils that had escaped me for years. Here's are some things I had missed.
In a general way of looking at the /6 archetecture, it says one thing in a big way: This cylinder head may be a perfect head for a 170 cubic inch engine, but trying to make a normally-aspirated 225 breathe through those same 170-sized ports is a job for Superman.
What I mean by that is, the ports and valves, as manufactured, are just too small for the amount of cylinder displacement they are asked to feed in a high-performance 225 environment.
The /6 has 225 cubic inches. If it had 8 cylinders it would be about 300 cubic inches with the same-size (37.5 cid) cylinders.
Just for comparison purposes to show what size these ports and valves are, the 1967 Chevy Z28 came with 302 cubic inches (virtually the same size cylinders as a 225 /6 engine,) and their intake valves were 2.02" in diameter (slant six "oversize racing valves" are 1.75", or fifteen percent smaller than the "stock" 302"-Chevy valves, and the 1.6" Chevy stock exhaust valves are still 6-percent larger than the "oversize racing" /6, 1.5" exhaust valves. To say nothing of the stock /6 valves...
The Z-28 Chevy ports in the head are commensurately larger, so that the flow numbers are a pretty good match for the valves, in their stock configuration.
The bottom line is, a mildly ported (302) Chevy intake port will flow close to 280cfm to feed the same size cylinder that the /6 is trying to fill with that 1.75" valve that is in a head, that after porting, will flow 220cfm, absolute max...
The slant's big, heavy, crankshaft doesn't help matters, especially when winding up 1st gear.
So, here's what I have learned:
I watched videos of the chopped, 2,350-pound "MadMax" 1st generation Valiant with a normally-aspirated /6 running 11.50s with NO power adder of any kind.
That car is incredibly fast and quick (watch how it hooks!!!)
I've never seen anything like it!
I didn't REALIZE that a normally-aspirated Valiant or Dart could run like that!
I happened onto two more videos on You Tube that opened my eyes even further.
There were two videos of turbocharged 225's that blew my mind. Tom Wolfe has a 3,300-pound '70 Dart that has run 11.02 with a new 225 motor (at 122 mph), into a 15-mph headwind, while another forced induction racer (turbo66Valiant) posted videos that showed his pristine '66 Valiant running some 10.70's, which is about a full second quicker than the already fast, but unblown, Mad Max car.
Not to belittle the Mad Max car, because it's stupid fast for its combination, but that '66 Valiant is I believe, 500 pounds heaver and a full second quicker. And, its running a 727 (heavy) transmission... probably about .2 and 3mph slower than it might have been with a 904.
So, what did I learn from all this???
Not so fast; I said I was a slow learner, and I surely am...
I did a lot of research about the /6 motor, and one thing stood out:
It's built like a brick pagoda. Its aluminum ancestry seems to have left it with an infrastructure that has no equal in the modern automotive world, when it comes to strength and ridigidity.
Remember that big, heavy, crankshaft I was carping about awhile back?
Well, I found that the early models are forged, have internal balance, and bearings the same size as the 426 Hemi.
As close to an unbreakable stock crank as you can probably find; it's short and stout!
The block's cylinder walls can be bored over .100", the head can be milled that much if need be, (over .100") and the top of the block is pretty thick, but I have no reliable numbers for that. I think it's thicker than half-an-inch.
What all this means is, unlike the Buick GN turbo motors which (the stock stuff) don't seem to want to stay together if the boost goes much over 20-pounds, it's an open question as to just how much boost one of these /6 motors could stand, if someone really got serious, because K-1 is making some great-looking forged rods for a 225, and forged pistons are available from Wiseco in a .065"-overbore, creating a 234 cubic inch motor.
Shaker223 and turbo66valiant are probably generating over 500 flywheel hp as we speak, but can 600 hp be far behind?
It's not necesssary to build a 500hp motor to have fun with a turbocharged /6.
One of Tom's early engines was pretty much stock with a Buick turbo stuck on the bottom of a stock exhaust manifold, and it went high 12's, in a 3,400-pound car.
The possibilities are endless!"
That kind of sums it up.
I was trying to point out the fact that, given the handicap of the original cylinder head, no amount of port or valve work, is going to make possible the kind of power-increases we seek in this 225 motor.
Ed (805moparkid) has a well-built '68 Dart that he has spent considerable time and money on in an effort to achieve impressive quarter-mile times. it has a minimal amount of "lightening" (a fiberlass hood, etc), and the usual hardware upgrades to its 225 slant six; I think it's bored, has a fully-ported head, with bigger valves, higher compression (I don't remember what the exact figure is,) headers, a 4-bbl carb and manifold, a re-curved spark-advance, a deep-geared 8.75" rear end, I believe, sub-frame connectors, a radical cam and some upgraded valve springs.
It is a well-built car, worked on by a guy who obviously knows what he is doing.
It has yet, to make a pass into the 13-second zone. Low-14's are "it," for now... Ed, correct me if I am wrong about that, but that was true the last time I heard a time on it.
My friend Tom Wolfe ((Shaker223 on FABO) took his bone stock 1970 Dart 225, added a 4bbl manifold, a 4bbl carb and a junkyard Buick Grand National turbo and went 12.98-seconds @ 102mph in the quarter.. No other changes; the stock head (with those tiny valves) had never been off the 100,000+-mile engine.
That's a full-second faster than Ed's car.... with a stock short block, and gearing.
I am not belittling Ed's efforts here; he's done a really nice job with that car and hasn't made any mistakes that I am aware of. What he's accomplished is what any competent mechanic/hot rodder could expect to accomplish with the same assortment of parts.
It's that ^%$#@&*%!!! cylinder head!
Even ported to the max, and with oversize valves, it is a bottle-neck that cannot be "fixed."
Unless...
A turbocharger makes an end-run around all those breathing problems.
Make no mistake; turbocharging one of these engines is not an easy task (but, it IS relatively cheap, compared to trying to get the same amount of power, naturally-aspirated.)
But, it's getting easier all the time, because of the burgeoning market in turbos and related equipment.
The fact is, you can make an easy 300 horsepower with about 12 pounds of boost on (good) pump gas, and still use your stock pistons and rods with good reliability. I would recommend two things; a water/alcohol spray unit for the intake charge, and a GOOD, wide-band, data-logging 0-2 sensor (such as sold by F.A.S.T.) for tuning the mixture.
That is the single most important piece of hardware you'll need, and to try this without it is.... just not something I would recommend.
A two-barrel carb on a Super Six manifold would be ideal.
A PISHTA-designed J-pipe turbo-mount would make headers unnecessary.
I honestly believe that even with the learning curve involved, the time spent chasing parts, and the time spent designing the layout, you'll still be money and time ahead with the hairdryer setup.
The advantages are numerous' the engine will make more power than a stock 340 V8, it will have excellent driveability (smooth idle and a lot of low-end torque,) LIKES a 2.73:1 axle ratio, both for performance and the highway, (so an overdrive is not needed,) it's quiet... the turbo homoginizes the sound waves, so you probably won't even need a muffler, and your stock 8.25" rear end is fine for this. A stock torque converter is also perfect for this app.
Opting for a normally-aspirated engine with THAT (170) cylinder head just seems counter-productive to me. You can easily spend $1,500.00 on porting and big valves in that head and still end up with less than 300 hp.... Ed had that setup maximized (as far as I could see,) and that was his case...
Albert Einstein couldn't figure out a way to put enough air through that head (naturally-aspirated) to make decent power...
All the hand-wringing, and brainstorming to get the best-possible breathing out of it is just a monunmental waste of time when a hairdryer is so (relatively) easy...
You can't make a silk purse out of a sow's ear.. and that little 170-designed head IS a sows wear on a 225.
But, there's away around it.... :cheers:
See; I told you I don't know when to shut up...
ops:Thanks Bill, all good info and interesting stuff. That is a possibility for the future of this engine just cause of the neat factor.
Not sure if you are aware though that my 225 is cradled in between the legs of a 6000 pound 4 wheel drive truck. My build is not for performance in that I would like to see it go fast, my build is for reliability/efficiency, I would like to make the engine operate as efficiently as is possible, its just a toy, something I have been playing with.
I do as mentioned like the idea of turbo, I would prob. be the only guy with that set-up in a vehicle such as mine and so I will keep all these facts in mind.
Just to throw it out there from what I have been reading on this site and slant org site installing larger valves in my head would be a complete waste of time/money but that confuses me cause I know the faster I can get air/fuel into the chamber and then get it out the better or more efficiently the engine will run so why not up-grade the valve size seeing how there is room for a larger valve?
Is it because the chambers leading up into the valves within the head just wont support or wont accommodate the extra fuel/air flow?
Yeah the DZ engine ran 2.02s but that was a performance engine from the get-go whilst the standard 327/350 ect were runnin 1.94 for many years on their 4 barrel cars/trucks and still kickin ***.
So if the cylinder jug diam on /6 is essentially same diam as the 302 than whats the drawback with the head to jug match?
I am confused but trying to understand better so that I can come up with my own conclusion that the / head on the 225 is a futile endeavor.
Not sure if you are aware though that my 225 is cradled in between the legs of a 6000 pound 4 wheel drive truck. My build is not for performance in that I would like to see it go fast, my build is for reliability/efficiency, I would like to make the engine operate as efficiently as is possible, its just a toy, something I have been playing with.
I do as mentioned like the idea of turbo, I would prob. be the only guy with that set-up in a vehicle such as mine and so I will keep all these facts in mind.
Just to throw it out there from what I have been reading on this site and slant org site installing larger valves in my head would be a complete waste of time/money but that confuses me cause I know the faster I can get air/fuel into the chamber and then get it out the better or more efficiently the engine will run so why not up-grade the valve size seeing how there is room for a larger valve?
Is it because the chambers leading up into the valves within the head just wont support or wont accommodate the extra fuel/air flow?
Yeah the DZ engine ran 2.02s but that was a performance engine from the get-go whilst the standard 327/350 ect were runnin 1.94 for many years on their 4 barrel cars/trucks and still kickin ***.
So if the cylinder jug diam on /6 is essentially same diam as the 302 than whats the drawback with the head to jug match?
I am confused but trying to understand better so that I can come up with my own conclusion that the / head on the 225 is a futile endeavor.
The Chebby 302's had 4.00" bores just like the Fords do. Both are 4" bore x 3" stroke. Cylinder volume may be close to the same as the 225, but the bore & stroke are not.
Any given port will have a max RPM that it will support for a particular cylinder volume. It simply chokes off the flow if you try to go above that RPM. You can increase the RPM by changing the pressure delta (turbo or supercharging), but that is about all that you can do without revising the port. A bigger valve on the same port is only going to buy you so much, and it could hurt flow by introducing turbulence where you don't want it. A high flowing port on a low speed engine will not work very well. I deliberately chose a small port head for a near future Chebby build because it is going into a 4WD. That engine doesn't want and can't use 300CFM ports.
There's a reason why modern cylinder head design employs supercomputers running Computational Fluid Dynamics programs (think 27th+ order Dif-EQ's), and those results are only as good as the assumptions made by both the program's writers and by the user. the rest of us have to cut and try. Even they eventually have to that.
I think the thing to do is to set a realistic max RPM, figure out where you need the Torque Peak and HP peak to be, and build the engine to come as close to that as you can. In the case of the Slant that upper RPM simply needs to be realistic in terms of it's cylinder head. Given that this is for a 4WD you probably aren't interested in turning 10,000 RPM anyway. So build to optimize max cylinder pressure from idle up to whatever your use dictates.
Any given port will have a max RPM that it will support for a particular cylinder volume. It simply chokes off the flow if you try to go above that RPM. You can increase the RPM by changing the pressure delta (turbo or supercharging), but that is about all that you can do without revising the port. A bigger valve on the same port is only going to buy you so much, and it could hurt flow by introducing turbulence where you don't want it. A high flowing port on a low speed engine will not work very well. I deliberately chose a small port head for a near future Chebby build because it is going into a 4WD. That engine doesn't want and can't use 300CFM ports.
There's a reason why modern cylinder head design employs supercomputers running Computational Fluid Dynamics programs (think 27th+ order Dif-EQ's), and those results are only as good as the assumptions made by both the program's writers and by the user. the rest of us have to cut and try. Even they eventually have to that.
I think the thing to do is to set a realistic max RPM, figure out where you need the Torque Peak and HP peak to be, and build the engine to come as close to that as you can. In the case of the Slant that upper RPM simply needs to be realistic in terms of it's cylinder head. Given that this is for a 4WD you probably aren't interested in turning 10,000 RPM anyway. So build to optimize max cylinder pressure from idle up to whatever your use dictates.
Thanks for your opinion. I do agree
I'd love to see some one like Edelbrock develop an aluminum head for the 225 with a modern ~9:1 CR combustion chamber and ports that will support 6500 RPM, even if they have to move the ports & rocker cover gasket rail up to do it. Put enough meat in the head gasket deck to allow cutting it to 11:1 CR and enough meat around the ports so that some guys could get a little crazy. Oh, and an undrilled EFI injector boss on the flat of the head above each intake for pishta. I'd buy one if the economy of scale is remotely close to there, say a bare head for ~$600. Something like that, out of the box, would make my 170 scream!!!
1930,
Thanks ffor the kind words; you're a patient man...
To begin with, I am going to say right off that I don't really understand the usage that you intend for this truck. You haven't said whether it's a daily-driver, workhorse, or what. You did say that it was going to be just a "toy," and that high performance was not a factor, in that it weighs 6,000-pounds.
My experience with cars and trucks is very limited. I have a handicap when it comes to talking about subjects like this, because I literally grew up (a long, long time ago,) on drag racing and that really skews my thinking.
The mere thoughts of using a 5,000-pound truck as any kind of a "toy" sets my so-called mind to thinking, "WHAT? 6,000 POUNDS??? PUT a CUMMINS TURBO DIESEL IN IT!!!"
I would contend that this environment is NOT a good place for a turbocharged slant six, and even with all the accolades I spewed forth last night, and as much as I admire and respect that engine, I don't think either IT or YOU would be very happy with such a collaberation.
So, forget I said anything. I run off at the mouth, (keyboard?) half-cocked at the slightest provocation and should not have entered this discussion because (as usual,) I didn't have all the facts.
One thing, though; the comment: " Yeah the DZ engine ran 2.02s but that was a performance engine from the get-go whilst the standard 327/350 ect were runnin 1.94 for many years on their 4 barrel cars/trucks and still kickin ***.
So if the cylinder jug diam on /6 is essentially same diam as the 302 than whats the drawback with the head to jug match? "
But, the CYLINDER DISPLACEMENT is the same on the 302 Chevy and the 225 slant six, (39 cubic inches,) the valve size is smaller on the six by an egregious amount (2.20" vs 1.75" intakes And 1.50" vs. 1.6" (Chevy) exhaust, and that is comparing stock Chevy valves to oversize MOPAR valves.
The reason for this difference in size has everything to do with bore-center spacing.
The Chevy V8 is built with 4.4"bore center spacing, vs. 4" for the slant. That's nearly half an inch difference, giving the G.M. car way more room for bigger valves.
The Chevy has a 4"-bore, while the slant six only has a 3.4", stock.
They have identical cylinder displacements because the Mopar has a 4.125" stroke, while the Chevy's stroke is just 3."
You can see the problem when it comes to moving air through this inline engine. It all goes back to the factory decree that the new (1960) Valiant was mandated to be designed with a short , low, hood, That dictated a short, low, engine. They had no choice but to engineer the block with small bores to keep the overall length as short as possible (and to lean it over at 30-degrees to keep it as low as possible.) They even took more advantage by placing the water pump alongside the engine, to help minimize length from the fan-to-the-firewall.
To exacerbate the problem, it was originally designed as a 170 cubic inch motor, and the head was designed with those parameters in mind.
The next year, when they needed some economical B-body station wagon engines, they found that the 170-inch version just didn't have the grunt to lug around 3,800-pounds comfortably, so they made it 33% bigger by stroking it a full inch. They were not in the mood to try and make it a runner, so they did NOTHING to increase breathing capacity.. so, an asthmatic, strangulated, 225 was born, sporting the same head that was designed for the 170 motor. That never changed on the millions of these engines that were eventually built. There was never been a better-flowimg factory head (except for some hard-to-get pieces that originated in Argentina,) and the aftermarket has never been interested because of the tiny bores... just no room for decent-sized valves.
So, it's no wonder that a 302 Chevy is a barn-burner race engine and a 225 cant even made INTO one, because of its physical limitations.
A naturally-aspirated, well-built 225 has amazing capabilities reliability-wise, but it can never make very much power; think of running a marathon with a piece of duct tape covering your mouth, and the picture becomes a little clearer...
I wish you luck. I feel that there are better engine choices to be made for your truck, but that's just MY opinion.... your mileage may vary.... :blob:
Listen, the 170's scream with the ORIGINAL head... They LOVE RPM!!! There was a guy named Pete McNicoll, who was one of the original Ramchargers (a team of Mopar factory engineers who excelled at drag racing,) who put a 170 into a '40 Willys coupe and ran it in the Gas Coupe and Sedan class that NHRA had for six cylinders back in the early sixties. It had a cast iron head on it (probably ported, with bigger valves,) and he took it to the Nationals at Indy. It was unbeatable. He ran 14-seconds flat at about 100 mph, eclipsing the performances of all the other sixes by a W-I-D-E margin!
That class was run by dividing the car's weight by its cubic inches, so it was all about specific output (cubic inches divided into the weight.)
A 170 slant six is virtually unbeatable in that type of racing. Nothing else comes close...
HOWEVER, this rant of mine is not about 170's because they are not big enough (cubic-inch-wise) to pull a 3,400-pound A-Body through the quarter-mile quickly enough to give the V8 cars' drivers the hives...
THAT is where the turbo 225's come in...
Unfortunately, the way I see it (and, remember, this is just MY opinion, nothing more,) no matter if you started from scratch with a clean sheet of paper, you'd never be able to design a slant six head that would make that 225 into a two-horsepower-per-cubic-inch motor, unless, you canted the valves, hemi-style, to get more room for bigger valve heads. With a true wedge design, there us just not enough room to do it.
A 4-valve-per-cylinder design could do it, easily (think Toyota Supra), but the valve-train complications, alone, would probably make that project un-workable. Think of the rockers and push-rods... unless you made it a SOHC or DOHC design... $$$$$$$$$$$$$$$$
The short answer to all of this is a hairdyer... It's so obvious to me, but then I'm an idiot... just ask my wife... :angry3:
Thanks for listening...
I enjoy reading everyones posts, I pick up a little from everyone, I dont know anything about problems in the past. Dont really care, new day.
I would like to learn about manifold port matching and blending. I am going to do what makes sense to me with this engine and this makes sense to increase its efficiency.
Id like to hear step by steps from some of you guys that have done this sort of thing.
Not a daily driver, maybe it will be after it gets a few scratches in its new paint. At this point just something that I am playing around with, learning new things and enjoying myself.
The old school, simple port matching advice was to 'paint' the flanges with dykem or a lot of Sharpie, align the gasket on the flange and secure it in place. Then lightly run a scribe around each opening using just enough pressure to scratch the dykem/sharpie and not deeply score the flange. Then carefully open up the ports to the scribe line and blend back into the port roughly 3/4" to 1 inch. "Blend" is the operative word, air doesn't like sudden changes in direction.
Then came the whole "Anti-Reversion" (AR) thought/method/"technology". This said to open the downstream port (head if intake, manifold/header if exhaust) to the gasket opening, but leave the upstream port a little smaller than the gasket opening. How much ? Who knows, I've seen numbers vary so widely that I'll guess at least some had to have shorts moved aside to grab them. If you know what I mean....
I kinda buy into the AR thing and I kinda don't. On the intakes I'd be inclined to bring everything to the gasket except for the floor of the intake manifold. Leave it above the scribe line by roughly 3/32" The point of this is to cause a little turbulence there in case of liquid fuel flowing down the port floor. Would like to toss it back up into suspension because it will burn better that way. Does this work? No idea, but it seems logical & like it should.....
Then came the whole "Anti-Reversion" (AR) thought/method/"technology". This said to open the downstream port (head if intake, manifold/header if exhaust) to the gasket opening, but leave the upstream port a little smaller than the gasket opening. How much ? Who knows, I've seen numbers vary so widely that I'll guess at least some had to have shorts moved aside to grab them. If you know what I mean....
I kinda buy into the AR thing and I kinda don't. On the intakes I'd be inclined to bring everything to the gasket except for the floor of the intake manifold. Leave it above the scribe line by roughly 3/32" The point of this is to cause a little turbulence there in case of liquid fuel flowing down the port floor. Would like to toss it back up into suspension because it will burn better that way. Does this work? No idea, but it seems logical & like it should.....
vntned
Well-Known Member
So to add fuel to the fire, since the heads flow was clearly designed for the small cube 170ci and not the 225. Would it be more profitable, if building a NA slant, to build a 170ci instead of the big 225?
I realize the 225 to have a torque advantage, but I imagine the peak hp levels would be similar.
Either way, I'm in the process of assembling a Hyper Pack 170ci for my '64 Dart. The dart is going to be a fairly period correct gasser but with a 170ci slant and a 4spd. Not going for fastest car, but Im hoping it runs in the 14s.
What do you think?!
I realize the 225 to have a torque advantage, but I imagine the peak hp levels would be similar.
Either way, I'm in the process of assembling a Hyper Pack 170ci for my '64 Dart. The dart is going to be a fairly period correct gasser but with a 170ci slant and a 4spd. Not going for fastest car, but Im hoping it runs in the 14s.
What do you think?!
I thought part of the process was to ensure that intake/exhaust manifold ports ( the actual intake and exhaust manifolds runners/outlets) were lined up with the head ports?
I though that the process somehow included some trick to ensure that fuel would be getting into the head with little obstruction, I have been under the impression that because of casting variations over the years between heads, exhaust/intake manifolds that ensuring this would be happening was a big part of all of this.
It seems to be that because of gasket variations that just the simple change-out of a gasket might spell problems with all of the work spent on the gasket matching deal?
I think you MIGHT be able to get it into the fourteens with a 170 if you put that Dart on a diet and get a 4-speed behind the motor, and outfit it with the right tires and gears.
Here is a picture of a friend of mine's Hyper Pack 1961 Valiant taken in about 1963. It was a 225, and didn't have the 10.5:1 pistons... he had, instead, milled the head .100". Everything else was regulation Hyper Pack..The car suffered from traction issues with the tiny 13-inch tires, and the gear ratios in those early Mopar 3-speed manual transmissions were pretty awful... kind of like a 4-speed that was missing 3rd gear.
He had the car at the strip a lot for about two years. His best time was a 15-flat at about 93 mph.
I can't imagine that a 170 would come anywhere close to that without fixing he transmission (ratio) issue and gearing it in the basement with some 4.56 gears and a pair of slicks.
A 4-speed would fix the tranny problem, and an 8.25" rear (or, an 8.75") would ne probably a really good idea, as the little 7.25" rear won't last long with any kind of bite.
The right clutch may be out there, but it will also be something to spend a lot of time researching, because this is going to be a low-torque, high rpm motor and you'll probably leaving the line at over 6,000-rpm... hard on clutches.
One of the Ramchargers (Pete McNicoll) had a 170 slant six in a '40 Willys coupe at the NHRA Nationals at Indianapolis in 1961 or, '62 (or, perhaps both years.) He literally dominated that class... none of the other 6-cylinders could run within a train-length of him.I was there, and it sounded like he was spinning that thing about 8,500 rpm. 170's will do that...
The fact is, though. a 225 is 33% bigger to begin with, and that is an insurmountable amount on the street to make up....
It's a GREAT race engine where they classify cars by dividing their weight by their engine size (cubic inches,) but in the real world, size matters...
The smart money is on the 225.... There's just no reason to try to do it with a 170 unless you're class racing (where the 170 has proven to be virtually unbeatable!) or, just trying to prove a point. The 225 slant six has almost no value in the automotive aftermarket/junkyard-world; people give them away all the time... If it were me, I'd replace that 170 short block with the stroker 225 and enjoy the extra 55 cubic inches... But, it's your money; spend it like YOU want to!
Back when Jack Clifford was still alive and I was just getting into Slants, my thought was the 170 over the 225 and make it a high RPM, NA engine. Jack sat me down and said "Lets talk". Just as Bill and others have said,Jack went on to explain the limits of the head and it would be a better Idea to build the 225 and think about "TORQUE" more than RPM. We all know that torque is what "moves" a object and when more torque is applied the object will move sooner,faster. And again we were talking about no power adders,just what the engine would produce on it's own.
This is just a thought coming up and has nothing to do with Slants,Please bare with me !
In reading all of this, and the compairson to the Z/28 302, I'll reflect on a story about a guy and his 302.Being a teen when the 69 Camaro was "new" and "THE" car to have I was working at a gas station(making $1 a hour) that was the local hang out of all the gear heads around the valley.Dave showed up with a shiney orange Z/28 4 speed 4.10 gears and of course the first thing was get it on the rack install the Hooker Headers and the Cragar SS wheels. The station was at the corner of a new 4 lane highway that was now the local street racers dragstrip.Well some of the other guys had 396 Camaros. As hard as Dave could he would wind up that little small block and get the big blocks out of the hole,1st gear, 2nd gear and then the "torque" of the big block would just drive around him and take the finish line.
Bill, I gotta say "Thanks for the memories" of some of the best times I had growing up. Now back to the Slants.............:wav:
This is just a thought coming up and has nothing to do with Slants,Please bare with me !
In reading all of this, and the compairson to the Z/28 302, I'll reflect on a story about a guy and his 302.Being a teen when the 69 Camaro was "new" and "THE" car to have I was working at a gas station(making $1 a hour) that was the local hang out of all the gear heads around the valley.Dave showed up with a shiney orange Z/28 4 speed 4.10 gears and of course the first thing was get it on the rack install the Hooker Headers and the Cragar SS wheels. The station was at the corner of a new 4 lane highway that was now the local street racers dragstrip.Well some of the other guys had 396 Camaros. As hard as Dave could he would wind up that little small block and get the big blocks out of the hole,1st gear, 2nd gear and then the "torque" of the big block would just drive around him and take the finish line.
Bill, I gotta say "Thanks for the memories" of some of the best times I had growing up. Now back to the Slants.............:wav:
vntned
Well-Known Member
Hmmm, interesting points.
I do have a '68 4spd to put in it, as well as an 8.25'' Sure Grip rear end with 3.55 gears.
Looks like I might be acquiring some true Hyper Pack 10.5:1 pistons on some rods. Probably 225 rods. Maybe I'll look for a 225, instead of using one of the 2 170s I already have.
Like I said, Im not really trying to break any records or go stupid fast, and I want it to be streetable, but itd be cool to smoke the tires and run 14s...
I do have a '68 4spd to put in it, as well as an 8.25'' Sure Grip rear end with 3.55 gears.
Looks like I might be acquiring some true Hyper Pack 10.5:1 pistons on some rods. Probably 225 rods. Maybe I'll look for a 225, instead of using one of the 2 170s I already have.
Like I said, Im not really trying to break any records or go stupid fast, and I want it to be streetable, but itd be cool to smoke the tires and run 14s...
roccodart440
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buy a scrap 318/360 for 400$ and your goal is a sinch.
I'm with the thinking that unless you are putting a turbo on it the /6 is a waste of money and time.
vnted, I'm all for "usin' what ya got", If it will be on the street more that just track duty. Will you be doing a full rebuild ? If not and just rings & bearings the 170 is a zero deck block where the 225 the pistons are in the hole quite a bit. I ran a 67 Dart 4 door with a stock bottom end 225,500 afb,intake and header, mild cam,automatic and head work. The car was in full street trim,open header, 4.30 gears.Best pass was 15.40 in Tulsa OK. I think you can be easily knockin' on the 14's door with your 64. Your goin' "Gasser" so you can loose quite a few pounds removing unnecessary items.
Look up 64 Dart 2 door sedan in member restorations. We are just about finished and will be trying it out at the track next month to see what it will do.
Look up 64 Dart 2 door sedan in member restorations. We are just about finished and will be trying it out at the track next month to see what it will do.
Given the way that the manifolds are supposed to "slide" across the gasket as they expand and contract with heat the ports will only ever be in perfect alignment at one specific temperature.
With Chebby's in particular the intake gaskets are all over the map. I'm not so sure this is the case with the /. There's likely to be minor variations, but with the thermal issue that I just mentioned I'm not sure "perfect" is ever achievable. "Close" is probably as good as it gets.
If you want perfect you're going to have to be able to get everything up to operating temp, and then look at how it all fits and aligns. At one of my former positions we had to do exactly that with a severely modified turbocharger that we built. We had to know what it did under thermal load, we even had to thermally load it and then drive it past it's service RPM limit and deliberately fail the turbine wheel to test our turbine scroll's ability to contain such a catastrophic event. To do this we built a combustion chamber that turned the turbo into a very fuel consumptive, extremely poor performing gas turbine engine. The compressor fed the combustion chamber into which we injected diesel at a varying rate. This turned the turbine wheel. With it we could raise the temperature of the test cell, about the size of a small bedroom, from ~70°F to ~90°F in about 10 minutes. Doing this had the turbine scroll orange-hot and an 8 hour run consumed a 55 gallon drum of diesel.
This is an early picture of testing the test stand. Virtually none of the component systems look like that now.
Starting it using a leaf blower to spin the compressor wheel:
Needless to say this was an expensive and time consuming project. I worked on that stand full time testing, tuning, and tweaking it for about 2 years.
Looking at the Offy intake it suffers from the same differential port length problem that my Clifford has. My own interest in the Hurricane manifold is hoped for better mixture distribution in a wet-flow intake.
And then you'll be unique, just like everyone else.
"Cinch" btw.
Thanks for your time and the pictures, interesting stuff, above my paygrade but interesting nonetheless.
My plans are this weekend to begin the soak and get the head cleaned up, I called a local machine shop and they want 50 bucks to clean it and 15 to magnaflux it. I can deal with the 15 but the 50 seems kinda steep.
After looking on-line and talking with a fellow car nut I have decided to try either Coke or white vinegar and see what happens.
My friend claims that a formula of water, powder laundry soap and one other ingredient that slips my mind will have it spotless in a week.
Id like to try the Coke so assuming the dollar store has it on their shelf I may start with that.
Will be posting pictures as I go. If there are any better suggestions please chime in.
My plans are this weekend to begin the soak and get the head cleaned up, I called a local machine shop and they want 50 bucks to clean it and 15 to magnaflux it. I can deal with the 15 but the 50 seems kinda steep.
After looking on-line and talking with a fellow car nut I have decided to try either Coke or white vinegar and see what happens.
My friend claims that a formula of water, powder laundry soap and one other ingredient that slips my mind will have it spotless in a week.
Id like to try the Coke so assuming the dollar store has it on their shelf I may start with that.
Will be posting pictures as I go. If there are any better suggestions please chime in.
Here's the thing; with the head on the 225, being the same unit that was designed for the little 170, it's just extremely hard to get a lot of power out of that motor, but not very hard to slip into the 14's with it.
A 14-second car is not slow... Hell, the bulk of the "musclecars" in the '60s would only run mid 14's, i8n showroom trim... I'm talking 389/400 GTO's, 383 Road Runners, 1966 390 Fairlane GTA's and 271hp hi-po 289 Mustangs....
You can have a LOT of fun with a 14-second car on the street.
Just be aware that some thoroughly modern imports with their 3.5-liter V-6s are that fast... cars like the Toyota Camry, Honda Accord, and the Nissan Altima... are all, low-14-second/100mph runners according to the road tests I read in the major magazines. Amazing...
But if you can be happy with mid-90mph/14-second performance, a 225 slant, naturally aspirated, can be the ticket in a 3,200-pound A-Body.. It's fully attainable and no turbo is needed...
If, at a later date, you want to go faster/quicker, forced induction is always there for you to try.
Im hoping for a mid-60s MPH / 23 second truck
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