318 power?
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HP2
Well-Known Member
I have two converters:
1. Hughes #24-35
2. The one in pictures. Does anyone know what it is?
1. Hughes #24-35
2. The one in pictures. Does anyone know what it is?
OldmanRick
Well-Known Member
It's a B & M Holeshot. 2800/3200 rating if i recall. My experience with those is their not very efficient.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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With closed-chamber alloy heads and just 10.45Scr, IMO, I think yur leaving some (a good deal of) performance on the table. The 4.10s will help with that, but Ima thinking she'll want quite a bit more than a 3000 stall.
The Wallace Calculator, at 10.45Scr; predicts about 153psi, which should run on 87gas.
In your Duster, with 4.10s and say a 3800stall; yur gonna need ginormous tires at WOT. 295/50-15s fit right in there, after you move the springs inboard. You may need to narrow the rear end.
Happy HotRodding;
I really mean it.
BTW
I ran that cam in an Eddie-headed, street 360, at 11.3Scr, for a cylinder pressure of over 170psi. (Those alloy heads are known to support 200psi, maybe a tad more. I myself have run them at 185psi on 87E10, with NO detonation). I ran it with a clutch, and an A833. With 3.55s, Second gear was 82 mph at 7000rpm; and the power didn't even start until about 60mph. First gear at WOT, was just a burn-out gear.
But worse, for me, was the lack of driveability at lower rpms in First gear with a starter gear of just 3.55 x 2.66=9.44..( With a hi-stall/automatic, you should be OK.)
I never tracked this combo.
In late summer of it's First year, I pulled it out and sold it.
And Yes; I moved that cam back and forth from 4* retarded to 8* advanced, and didn't like it anywhere in between.
With 4.30s it was a beast, but on the street with a clutch; that got old in a hurry.
QuickDart360
Well-Known Member
I run that 292 purple cam in a mild 360. It runs fairly strong on the street. I set mine up 4° advanced @ the crank. 3.91's out back. In a dart sport & its pure fun to drive. Just a pleasure.
HP2
Well-Known Member
I had to make a choice yesterday and I used the B&M. I picked it because it's smaller and would give a higher stall speed.
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It'll be enough power to be FUN driving and turn some decent times in at the strip. Isn't that enough?
HP2
Well-Known Member
Thanks for your input!
I know it would be better with a higher CR but I didn't want to mill the heads since I don't know if I will sell the 318 or putting it in something else with another cam. I will check the cylinder pressure when I get it running just for fun.
My cam is installed at zero. If the engine hadn't been put together or if i have had time I would have advanced it 4 degrees to match the intake a little better.
We'll see what that converter stalls in reality, i can only hope it works okay.
Now the engine is in place, I had a little hell with engine mounts. I have been more into big blocks and I always forget the setup for smallblocks haha. Hope to get some hours in the end of the week to work on some details before it's time for engine startup...
I want to build that 340/377 since I like the stroke to rod length ratio for what I'm intending to build the Duster for. I'd love to put a long runner tunnel ram on top for different reasons too. That engine will get a mechanical cam and it will be fun to sort everything out when it comes to cam profile, converter, gearing, tires aso.
Car has had the leaves moved inboard at some time so it is pretty simple to put them there again. Now it sits a little high in back, but it looks cool
AustinGriggs
Well-Known Member
My KB167, 318 with less compression and ported J heads made 292.3 HP to the tire and ran the 1/8 in 8.35. So I assume you could be in that neighborhood.
HP2
Well-Known Member
That's pretty impressive. Auto or manual? What cam and intake? At what rpm did it peak?
Dartswinger70
Well-Known Member
best answer, I was going to say "lots and lots..."
Steve Bloom
Active Member
Motors work better when all the parts are harmonious with each other. Like someone said, measure twice. Bigger ports don't always mean more power. It's all about pushing the piston down. Air and gas volume matched exactly to the rotating assembly and spark timing coupled with balancing. I'm guessing 280HP with that combo.
Dale Davies
Well-Known Member
Wellll, parts he already has in the shop/garage. Nothing wrong with that. Sell stuff off and purcase replacement? Not exactly wise unless selling a collector item for big $. Only a 318? That is only 22 cubes smaller than a 340. So if you are looking at the power/cube and about 400HP, the difference should be about 30HP. Now the 340's larger bore unshrouds the intake more over the 318 which should provide a bit of a benefit. That said the valve size and combustion chamber are the biggest concern.
Now the cylinder displacement and expected 2.02 intake valve size indicates the LSA should be 106°. If the 108° cam is on a shelf, I would use it as it will be much better than the catalogue 110° and 112° cams marketed and "popular" today. Early electronic carbs with an O2 sensor and throttle body injection were sensitive to overlap, dictating wider LSA to keep raw fuel out of the exhaust. With modern injection and tuning or plain carb intake, the narrower LSA will provide better total performance. Yes, idle will be rougher and low speed torque may be down a bit. The driving package or combination is the consideration and end result.
To the OP, toss it together with the parts you have.
To the poster yipping about balancing, do not get me wrong, I do encourage balancing an assembly. Let me relate a story though. Years ago some younger guys were into racing Mopars. They would scrounge for big cams of the day and gears. They were turning what I consider crazy RPMs on unbalanced short blocks. Finally one came into the service station I worked at and told me he had purchased a balanced short block as I had been recommending. That lasted 1 week to the first missed shift and the block got aired out. No more talk of balancing allowed due to the extra cost. They still vented blocks but saved the balancing costs. Without missing shifts a balanced rotating assembly should run smoother and longer. With the balance, a cc to bring combustion chambers to the same volume will aid smooth running as well.
Dale Davies
Well-Known Member
Yes the big blocks make more power or torque easier. However they are big and heavy which is a detriment. For a tow vehicle/work truck pulling a trailer regularly, yes a big block is the way to go. For a light and nimble street car the small block is a better all around choice. Dropping in a big block makes the car into an arrow. Inertia on that mass up front anchors the front and the rest follows.
Disagree since I have been there and done that and I’ll just say it outright so there’s no miss understanding…
Your wrong - Here’s why.
While the big block is heavier in stock form the only avenue I’d capitulate on and only to a degree since heavier leaf springs and T bars will greatly help this out, the big block can be very well equipped with aluminum save the short block unless a lightened crank & aluminum rods are OK with you. This can easily bring the weight down to a stock small block. While true! A small block can do the same, the weight loss isn’t as great but will be lighter. Your still behind on cubic inches.
I would not use the big block for carving corners but that’s not to say they can’t do well.
I’ve own and drive a 400/727/8-3/4 ‘71 Duster.
Also FWIW, I’m a small block nut.
Not so much on big blocks.
Swinger 340
Well-Known Member
Front, Back, the outcome is the same!!!!!
Dale Davies
Well-Known Member
I will give you cubes rule for torque. HP is a calculated value from torque and RPM.
Yes you can reduce the weight of the big blocks with aluminium heads and intake. Lightened reciprocating components can take more off. And you are correct the same can be applied to small blocks. The effect will not be as dramatic due to the inherently smaller component sizes reduces the amount reduction. Now some engines respond with dramatic weight reduction with aluminium heads and intakes. The hemi is one. The volume of cast iron used to cast those monster heads is phenominal. Another is Ford FE series when Al heads and intake are used. Their heads are not too bad, but the Fe intake is a brute! Now look at the SBF. 289 and 302 came with cast 2V intake and weigh about 480 lbs. Replace the top end with Al and that already compact and light engine is down to close to 400 lbs.
The bottom line is intended use and expectation. If you want to tow a loaded 5th wheel trailer daily, a big block has the meat to handle the stresses and vibration better. Can a small block be built to the needed torque and power requirements? Usually yes. But it will normally not last as long. That is why heavy duty truck engines weigh 2500 to 3000 lbs. Lots of cast to absorb the generated stresses. Then there is the industrial engines that weigh tons, run at 1300 RPM for months on end. It is intended use.
The big block in city driving can tend to negatively effect fuel economy. But you put tall gears in and let it idle up the freeway and fuel economy will be fairly good. Take that same vehicle and be a boy racer with 4.30 gears and you best be partners in an oil company.
I stand by my statement, a regular street driven car or light truck is better served with a small block. Drag racing or towing is better served with a big block. In the '60's many people with holiday trailers owned cars with big blocks to tow them. GVW was not monitored as much as the people driving Caddies, Olds, Buicks, Pontiacs, Chryslers and Lincolns did not seem as inclined to rip up freeways at 90 MPH while towing a fairly large trailer. Now you have the village idiot crowd that can not read functionally, driving a lifted 3/4 ton pulling a trailer at 90 MPH.
I don’t know why your brought in other brands, I thought we were talking about 318’s and I he interjected big block which really has no place here.
Perhaps your in the wrong forum.
And his has to do with what on the thread subject?
So far, you have taken my comment very far out of wack way beyond its meaning & context and twisted it into a nonsense post that has nothing to do with anything.
Why are you posting here?
Why the F are you bringing Fords into this?
Perhaps your in the wrong forum.
WTF are you talking about now bringing in the 5th wheel?
So now your bringing in heavy duty truck engines only followed by, tractor trailer semi rigs?
And his has to do with what on the thread subject?
So far, you have taken my comment very far out of wack way beyond its meaning & context and twisted it into a nonsense post that has nothing to do with anything.
Why are you posting here?
fratzog lover
Well-Known Member
Dont underestimate or try to "upgrade" the Weiand Stealth intake. It is actually a very good intake that doesnt get the recognition the RPM and Air Gap do. It wont be the piece that restricts your power level unless you really mismatch some parts in the build.
Stealth is a good intake with the dreaded according ot some 273/318 sized intake ports. Spend a couple minutes opening then up and blending up the runners and you are good to go with it. Same with a Performer 318/360 intake, work fine especially with a a little elbow grease.
One thing with the intake, they have a tendency to run lean on the deep plenum side occasionally. Deep side +1 on jet sizing sometimes.
Steve Dart 69
Member
Sounds like that engine will be a real screamer. Your engine specs remind me of a engine I had built in the early 80's and put in my E body.
30 over 340, standard 10.5:1 compression, standard 340 crank cut 10 under on rods and mains, balanced lower end rotating assembly, custom machined large valve heads, spring and valve guides stems cut to allow plenty of compression due to the high lift cam. The cam was a hydraulic flat tappet and had a 512 intake and 525 exhaust. I had to find the adjustable rockers, spacer springs and push rods from a earlier 273 hp engine to get the proper valve adjustment. I had a MSD and factory electronic distributor, fuel was fed through a 6 pack set up with all carbs set up with mechanical accelerator pumps and power valve metering blocks with mechanical progressive linkage.
That engine screamed up to 7300 rpm's and was well mannered as a daily driver. The car was a blast to drive, good luck with your build.
30 over 340, standard 10.5:1 compression, standard 340 crank cut 10 under on rods and mains, balanced lower end rotating assembly, custom machined large valve heads, spring and valve guides stems cut to allow plenty of compression due to the high lift cam. The cam was a hydraulic flat tappet and had a 512 intake and 525 exhaust. I had to find the adjustable rockers, spacer springs and push rods from a earlier 273 hp engine to get the proper valve adjustment. I had a MSD and factory electronic distributor, fuel was fed through a 6 pack set up with all carbs set up with mechanical accelerator pumps and power valve metering blocks with mechanical progressive linkage.
That engine screamed up to 7300 rpm's and was well mannered as a daily driver. The car was a blast to drive, good luck with your build.
Dale Davies
Well-Known Member
Just examples to compare and to illustrate situations for intended usage. I did mention the Hemi engines and their benefit with Al heads. What does a SBM weigh? The SBC is about 570 lbs. I expect the 351W to be similar. These are with cast intakes. Suprisingly the Caddy 500 is not much heavier than a SBC.
I used to like Mopar but much after '73 they went for a powder and never came back. The leaning tower of power is an awesome engine. As long as it had oil and water, it ran forever. Like all long stroke engines, it is not liking high RPM. Now the little 170, those you could buzz pretty good.
All makes have their strong and weak areas. Being aware of those and being able to apply those to your favorite weak spot can create a better build.
In bygone days, Mopar kind of devoted their attention to drag and NASCAR efforts. They did have a short foray into TransAm and performed respectably. Money tossed at factory teams kind of buried Mopar in the avalanche. Then SCCA changed the rules which pushed the pony cars aside. Too bad as it was heating up. But then the fuel crunch and insurance kind of killed muscle cars. Would have been intersting to see a couple more years of the Camaro, Mustang, Javelin, Cuda, Challenger and Firebird racing.
Dale Davies
Well-Known Member
There used to be two Dusters ran the 1/4 at EIS in Edmonton, Alberta, Canada. Both 340 cars and identical except color and transmission. One was stick and the other auto. One time the stick would win and the next may be the auto. They could switch cars to see if driver made a difference. Now reaction time is a big part. Transmission choice in the Mopars did not seem to make a difference. The other breeds was a different story, and the Mopar automatics lasted. All the automatic trans shops would have gone broke long before they did if all the automatics lasted like the Mopars. The Mopar weakness was fast idle and the R band.
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