Opinions on low end 360?

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rumblefish360 said:
well, I made the cam choice based on getting the most power out of the combo while retaining power in the cruise range with the 3.23 gears and 275 tires which comein about, 28 inches?
The next cam down would be so bad ether.

Your idle time is just that. Idle. Not really moving. And if so, through the parking lot?
Cruise speed. The cams listed RPM range is 1400 and up. It will pick up some over 2200 and feel all right from 2500 and above, where you'll be driving at, on the Hwy.

So, is it stupidity? The idea of a cam not being flexable enough or a car/engine/drivetrain set up not being flexable enough is not seeing the big picture. IF you feel my suggestion isn't fitting and I fall under the stupid, OK fine. I'll accept the insult and carry on. Sorry for bothering you.
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I did absolutely not intend to assault you or anyone else! I really apologize if I did. English is not my first language so I guess I sometimes write in a way that sounds rude. I guess it differs in how we speak too. Our language can sometimes sound a little blunt. That's how it is here in cold Sweden. Sorry again, and I mean it!

I have put together some engines over the years, not any small blocks, and I have eventually realized that I have built engines for street racing and I don't street race so often any more. And never will with this car since i have a 71 Charger for that purpose.

I don't exactly know how i should put this to not make people angry again. The 360 i have is a typical hot rodded small block. It runs pretty okay from bottom and gets happy at 25-30 miles on first gear. The power curve climbs higher then I dare to keep my foot down. Very fun in a way but not what I'm looking for. The 2,200 converter helped a little but I still missed my goal. Then I started thinking of if it would be possible to build a very low end power engine that really met my needs. I am not interested of what happens beyond 3,500 rpms since I very seldom will be there.

The long ram intakes that Chrysler put on heavy cars in the early 60's has been a source of inspiration for me. They was built with a similar idea. IIRC they made maximum torque at around 2,800 rpm's and there's a good point in that. Passing-without-downshifting-kinda-power :)
Now I don't have any plans of trying to build long ram induction for my 360, but 5.9 liters is not a very small engine after all and I still think it would be possible to get a happy low end engine with that displacement with a 180 deg intake, a good cam and a suited compression ratio and combustion chamber. And in these terms I really mean idle to around 3,000 rpm's. There's very few freeways in Sweden so even if I would drive long distances I would be cruising at around 50, sometimes at 60 mph, but more often at 40 on winding sideways and byways. Maybe I would have said that in an earlier moment...

My wish is to get a snappy, happy engine that easily breaks these 275's loose from standing still and purrs like a kitten under 2,000 rpm's. I have no idea how much peak torque/power (or little) it would make. The numbers would probably not impress anyone, but the seat of the pants impression could be something else. It would probably be easy on gas too.

Maybe I'm the one who's a crazy stupid oddball?
 
he 2200 converter has been my biggest question here. It will work..... but throws away much of the low RPM advantages that you want. I would for sure be putting in a stock one.
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Exactly. And, "Wants to roast 275's"
 
I agree the TQ secondaries are too big, but what better option do I have?
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The TQ is a win win on every front for you.

TQ's are a solid fuel metering carb with a dual stage booster and small primaries. What does that mean? In short that means the small primaries and booster design makes for great torque and throttle response and as its a street car most of your driving will be on the primaries anyway.

The droplet formation of this design is also better than single stage booster carbs like Edelbrock and Holley designs so better combustion is the result. Smoother and more torque

Idle circuit design is superior on the carter as well so a better idle and transition.

Vacuum actuated rod and jet design is far better than a holley power valve at metering fuel.

Large vacuum actuated secondaries essentially give you the carb size your engine needs at that moment. They only operate when you need them. A vacuum secondary carb will have a larger range of operation because it only gives your engine what it needs not like a DP Holley

Plastic bowl keeps the fuel temp lower.

They are cheap as chips except for tuning kits.

And the calibration should be near perfect for combo!

Hysteric
 
IQ52 Funny you should mention 318 heads on a 360 I had a similar set up but with ported 302's 1.88 and 1.60 valves,11-1 comp and a 256 @.050 on a 108.

The torque was truly amazing and continued to pull hard even to 6000rpm where the limit was set on the msd. Only had 3.55 gears too.


Hysteric
 
AJ/FormS said:
I said I have made TQs work on teeners,Right? It's all about tuning. And I have Tuned a 600(list 1850) to get 32mpgUS, so Holleys can be made to work. Again, it's in the tune.The TQ has no aftermarket support, so tuning it can be a challenge. But since your build is so mild, it may work with minor adjustments. And like I've always maintained; I LOVE TQs.

The problem I forsee with a Small TQ on your build, is transitioning.
When you floor it at the bottom of first gear, your TC will flash to it's stall. Then the car will accelerate in first gear to 3500/35mph and the secondaries may have just begun to open. But you are shutting down. So the secondaries slam shut, leaving a huge puddle of gas sitting in the manifold. As soon as you again open the primaries, guess what, that fuel starts moving. And your plugs are not gonna like that. If you get tirespin, it will be less of an issue, but as you feather the pedal out, and the tires hook, the secondaries will again close, allbeit dryer this time.
No, for you I see a very small mechanical secondary 4bbl as a nice option. You will get all 4 bbls whenever you hammer it. You will be able to control wheelspin with the footfeeder, and feather it out as you approach your target mph or rpm.On the flipside, with no tirespin, you won't have fuel puddling under the secondaries from them suddenly slamming shut, so, getting back on it in mid-stride will be smooth and uneventful.
You can tune the TQ to minimize that puddling thing, or you can modify your driving style to work with those secondaries. Neither of which I would want to do. Furthermore, that vacuum sec carb will not let the engine unleash all its potential, at city cruising speed.
Say you are tooling along at 30 mph. with 3.23s and 28s in third this would be about 1200rpm,plus TC slip. But you wanna G-O, so you hit it! Tranny shifts down to second, and rpm climbs to 1700 plus slip/stall,say2200 . Well the secondaries might as well not be there,cuz they are not coming on line til around 50 mph. So what do you do? Slam it into manual low. So now the Rs climb to 2850 plus slip, say 3200. Ok now the secondaries are beginning to open. In just a little while they will smoothly come on line, as the vehicle smoothly accelerates;no drama.
I like drama. Capital D,Drama. I want tirespin, smoke,screaming pipes,and hard charging look-at-me-go. Especially with passengers on board. Like why do you think I spent a years wages on this beast, for smooth acceleration? Heck-no!
So for me it's a DP hands down. For you, if they make em in a 500, that would be big enough.And nicely controllable, and light 'em up at 30mph big fun, with giggles and smiles for everyone.
Ok enough bs already.
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No, no bs at all! I love the Drama you describe too. I think I fully understand what you are saying and I'm not late to agree that four tiny ports would be better than two small and two huge vacuum controlled. Good for high velocity and good response. The sad thing is that I will be dependent to the Holley style... Four same size holes feeding is easy to control and tune, but Holleys are not really made for part throttle. That's still my opinion.
TQ´s have some very clever solutions after all. Take a look at the new Street Demon, it's somewhat a copy of the TQ and a member here says he loves it. http://www.demoncarbs.com/1900.asp
625 cfm might be a little too much, but better than a TQ. Yes it is a vac secondary but maybe more suited for what I'm after if it's possible to tune all the way?
I had a vac sec on a street driven low 12's 440 in my Charger and I managed to tune it very well. Then I have to admit that I picked up almost four tenths when I went DP :)
The smallest Holley DP I can find is a 600, but if I want the Ultra (more tuneable for street) then 650 is the limit, and DP's are less forgiving when it comes to oversizing... And $550...
Thorny subject, hmmm :???:

Standard stall converter is getting closer though :)
 
Hysteric said:
The TQ is a win win on every front for you.

TQ's are a solid fuel metering carb with a dual stage booster and small primaries. What does that mean? In short that means the small primaries and booster design makes for great torque and throttle response and as its a street car most of your driving will be on the primaries anyway.

The droplet formation of this design is also better than single stage booster carbs like Edelbrock and Holley designs so better combustion is the result. Smoother and more torque

Idle circuit design is superior on the carter as well so a better idle and transition.

Vacuum actuated rod and jet design is far better than a holley power valve at metering fuel.

Large vacuum actuated secondaries essentially give you the carb size your engine needs at that moment. They only operate when you need them. A vacuum secondary carb will have a larger range of operation because it only gives your engine what it needs not like a DP Holley

Plastic bowl keeps the fuel temp lower.

They are cheap as chips except for tuning kits.

And the calibration should be near perfect for combo!

Hysteric
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That's exactly why I don't like Holley's on street driven engines, and that's exactly why I do like TQ's in the same element. But AJ still have a point with the difficult to control door, right?
Is the Street Demon 625 a considerable option here?
 
How is the spring loaded external screw driver adjustable secondary door a problem to control and adjust?

Sounds like you believe old wives tales more than anything.

"Don't step on a crack, you'll break your mothers back!"
LMAO!

IMO, a 625 is OK and fine to use.
 
On the demon carb I have the phenolic bowl one, it works excellent right out of the box.
You do have to dissemble the carb to put a mopar throttle arm on, not a big deal, just a few bolts.
http://www.summitracing.com/parts/dem-1901/overview/

ud6b.jpg
 
still have a point with the difficult to control door, right?
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The design is sound the monkey adjusting it is the problem.

Hysteric
 
HP2 said:
Planning to do some upgrades on my 70 `cuda vert, I will keep the 904 tranny with the 2,200 rpm converter and will stay with the 3.23 SG. Brand new tti 3" H-pipe exhaust is already installed, did that before I made decisions about the power plant.

I don't know very much about the 360 yet. It takes no oil, has good compression and runs strong. Power comes in strong at around 3,500 rpm's and then it wants to rev to the moon. A little screamer. Recent owner said it was a "crate engine", but he couldn't confirm it. I have found out that block is casted 1971. It is externally balanced.

I want an engine working with the converter and 3.23 ratio.
I'm looking for a power band suited for the rpm range the engine will be driven in. Rarely over 4,000 and mostly between 1-3,000.
Plain and simple responsive and economic motor.
You might think I'm odd wanting to build such a boring engine, but I have had many cars with hot engines making lots of power, and as we all know high revving engines like that requires high stall converters, high flowing induction and exhaust, steep gears and so on. Honestly, most of the time they are not very fun though. Not very reliable either. But thirsty. I still have my Charger if my mood turns to racing mode
laugh.gif


I think this 360 still could be able to smoke the 275's. Do you?

Hopefully I will be able to use the same crank, rods, pistons and heads. Of course more cubic would take it longer, but I'm on a budget.
I'm thinking a good aluminum dual plane with long runners like Edelbrock RPM or Weiand Action Plus and a Thermoquad on top. Long runners are good for low end!
Camshaft selection will of course be very critical and here I need advice. A good bunch of lift, steep lobes but not much duration? Any opinions?
I will ditch the headers since they are crap. Maybe I could go with cast iron manifolds since I don't need a lot of flow?
If my heads needs work it might be a better idea to find something else. If I stay with iron I will aim for 9.5:1, if I can afford aluminum then 10.5:1
Will also have to get a distributor with vacuum advance.

Let me hear what you think folks!
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Update:
Took one head off last night and the pistons are .090 down the stroke.
Cylinder bores look good, not much wear.
Has scored a Performer intake and three different Thermoquad's.
Also found a pair of unknown used headers in usable condition.
Will use a factory stall converter.

Now with the disappointing fact that the pistons are below deck I need advice to be able to move on.
What cam would you use?
 
Well, Here goes nothing...... With pistons down .090, your Scr is about 8.4.
To me this is bad news,for what you are trying to do.
It is my opinion;that you will need as much Dcr as possible.
If you have to start from such a low Scr,the cam will need to be very small indeed.Extremely small. If you are on a serious budget, you might consider a good used oem 360cam or even a teener cam.Even a tiny 252/112 cam, will put the Dcr down around 7.25, which is pretty soft. The 2200TC will help get your revz back up, but since you say you will be keeping the revz down, your engine will be constantly operating in the 7.25 to 8.4 CR zone. This operation, in a heavy E-vert will not be fuel efficient.Nor particularly snappy.It wouldn't take much math to justify a new set of hi-Cr pistons.

Getting a set of pistons to Zero deck, might get your Scr up to 9.65 with 86cc total chamber volume. This with a 260/112 cam, would bring your Dcr up to 8.1ish, and your engine will now be operating between that 8.1 and 9.65. This will make a much different engine, especially since you will be operating in a throttled to heavily throttled condition,some 70% or more of the time(a guess,to be sure). I'll take a wild guess that this engine might get at least 1.5 to 2 mpgs better around town and double that, in steady state. In Canada,In about 6000 miles I will save the cost of the pistons. In 10000 miles I can easily save the cost of the pistons and the labor. In the Usa, I imagine you will break even, a lot sooner.
The KB line has a piston with a specialty dome on it, that can be adjusted to make a tight quench, in an open chamber head.

There are other ways to get the Dcr up. You just need a smaller total chamber volume than the approximate 100cc that you now have. That .090 down is costing you 18.5cc
 
Talked with Kevin @ Comp and this is what he suggested:

INT DURATION 212 LIFT .305
NUMBER OF DEGREES NON-SYM (SEE NOTE BELOW)

EXH DURATION 218 LIFT .315
NUMBER OF DEGREES NON-SYM (SEE NOTE BELOW)

LOBE SEPARATION 110 ADVANCE 4 ROCKER RATIO 1.5


THESE SPECS ARE FOR CAM INSTALLED AT 106 INT C/L

INT OPENS 0 BTDC INT CLOSES 32 ABDC

EXH OPENS 43 BBDC EXH CLOSES 5- ATDC

INTAKE VALVE LIFT .4575 EXHAUST VALVE LIFT .4725

WANT TO DO ANOTHER ? (Y/N)


* NOTE FOR ASYMMETRICAL DESIGNS *
FAST OPEN/SLOW CLOSE - ENTER NUMBER ONLY
SLOW OPEN/FAST CLOSE - ENTER NUMBER AND "-" (MINUS SIGN)
 
Don't have time to change pistons now, plus I'm still on a pretty tight budget.
Think I forgot to mention that the heads are J-heads. I haven't cc'd them yet, will try to do it the next few days. I have a friend who can mill them for me if it will do any big difference.
After the summer I will have the block honed, get new pistons - or even a stroker kit, probably buy a pair of aluminum heads and build the low revving torque diesel like engine I really want, but for now - I don't know!
Mill the heads? How much?
Get a new cam and lifters.
Get a vacuum distributor
Put it together with the Performer intake and a TQ and drive it.
Hopefully will it perform a little better than before.

Still very thankful for all your input gentlemen!
 
Make sure you use the thick gasket under the TQ to keep it properly cool and at the correct height for the choke to operate.

Milling the head down for more compression is OK to a point. Then the intake becomes harder and harder to fit. You need to cc your current head and then do the math on the milling specs and final cc amount to arrive at the ratio you want. Considering the Comp Cam recommended cam, (or that smaller cam I mentioned) I wouldn't go to far.
 
HP2 said:
... But AJ still have a point with the difficult to control door, right? ...
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Not sure where that comes from? The secondary air door is infinitely adjustable with no parts to buy. You can also change the opening dimension, smaller or larger by bending a tab on the door.

As for milling, "J" heads take .040 to get the largest chamber to 64.7 cc. They usually run down to 1.5 cc smaller for the smallest chamber. Mill the intake side of the head .038, so you won't have any problems with the intake manifold. I typically only mill heads .020 and .019 on the intake side to get a good seal. That will leave you with approximately 68.7 to 67.2 cc chambers
 
You know how it is... The great mystery of cam voodoo, not understand TQ's at all and assume some more.... Just claim the Aliens did it.
 
Okay, here are my actual numbers:
J-heads cc's to 68.5
Pistons .090" down = 17.2 cc
If I use a .022" aluminum head gasket and mill my heads .040 I get around 9.7:1 (if I calculated correctly).
Am I back on track now?
 
Here is just a suggestion for thought: You might not want to mill the J heads at this point if you think there is any possibility to re-use the J heads later. If are going to put in new pistons later on, you may end up with too high of an SCR unless you already have planned what the later pistons will be and what head CC's you want to end up with later. If the new piston tops are higher up in the bore later, you can only put in so much more head gasket thickness to lower the SCR once you have milled the heads down.

Of course, if you are definitely going with the AL heads later, then there is no problem with milling the J-heads now.
 
nm9stheham said:
Here is just a suggestion for thought: You might not want to mill the J heads at this point if you think there is any possibility to re-use the J heads later. If are going to put in new pistons later on, you may end up with too high of an SCR unless you already have planned what the later pistons will be and what head CC's you want to end up with later. If the new piston tops are higher up in the bore later, you can only put in so much more head gasket thickness to lower the SCR once you have milled the heads down.

Of course, if you are definitely going with the AL heads later, then there is no problem with milling the J-heads now.
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Yes, those thoughts has been spinning in my head for a time now :)
I have come to this decision; I want to put this 360 back together with milled J-heads and some good cam. Hopefully it will be good enough for cruising around a summer or two. When I do it next time I want to do it all the way. Probably with a stroker kit and alu heads.
If I shave off .040 off the J-heads they will not be ruined for someone else in the future.
Thanks for your input, now it's cam hunting time :thumblef:
 
Now I've read through this thread thoroughly. This sounds a lot like my dream engine.

I'll be looking forward to hearing how things turn out!
 
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