looking for cam and pistion ideas.

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Cope

Cope

Fusing with fire
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Im looking for some ideas as far as cam and pistion combos go.

Ive got a 74 440 at 40 over. Factory deck height (for now)
906 heads (not milled) with 1.6 roller rockers, dual coil springs, 2.08 intake valves and 1.80 exhaust W hardened seats and bronze guides. (not flowed, so no numbers yet)
Victor intake and 750 DP Carb.
forged crank and LY rods. (I may go H beam)
MSD distributer (with out vacuum advance) and 6AL box.

Rear gear will be low 4.88 ish.
Stall converter will be high, 3,500+?


This is a race first and street second engine.

I would like to be able to run 92 octane.

So just how much cam can I throw at this sucker?
what is a good comp ratio and pistion to get me right to the edge of pump gas?

Im not quite ready to go full roller so keep that in mind.

If theres other info needed just say and i will provide it, if I can.

Thanks for all your time and advice.
 
Shoot, I got the tires at the shop but dont remember the exact size

.
 
4.88 is alot of gear for a 440 unless you have some pretty tall tires....
 
The more cam you throw at it the more compression you can run, in general.
For 92 octane an iron headed engine can run 10-1 and nearly any aggressive cam.
Generally speaking.
The old MP 440/500 cube create engine ran a advertised 9.0-1 and a 292/.509 cam for an advertised 505 HP.
To make use of 4.88's and a 28 or 29 inch tire, you could use, for example, the MP .557 lift cam (approx. 250@.050 duration and as small as I would go) and larger. The .590 lift cam (approx. 265@.050 duration)would work on a 10-1 iron headed engine. Though a fully ported iron head would be more of a matched part as a stock head would not be. (For both cams.)

This is in general since there's more than 1 way to skin a cat.

Considering it is a stock head, look into split durations to assist in better breathing and performance.
 
rumblefish360 said:
The more cam you throw at it the more compression you can run, in general.
For 92 octane an iron headed engine can run 10-1 and nearly any aggressive cam.
Generally speaking.
The old MP 440/500 cube create engine ran a advertised 9.0-1 and a 292/.509 cam for an advertised 505 HP.
To make use of 4.88's and a 28 or 29 inch tire, you could use, for example, the MP .557 lift cam (approx. 250@.050 duration and as small as I would go) and larger. The .590 lift cam (approx. 265@.050 duration)would work on a 10-1 iron headed engine. Though a fully ported iron head would be more of a matched part as a stock head would not be. (For both cams.)

This is in general since there's more than 1 way to skin a cat.

Considering it is a stock head, look into split durations to assist in better breathing and performance.
Click to expand...

old mp 557 cam is 258 @.050......well..after you buzz the motor..with 29 tire and 4.88 gears...I would use a 4.30 gear with 29 tall tire...
 
I have always liked the 213462 JE pistons at about 10 to 10.5 to 1 and have had great luck with them in my big blocks. I always call and talk to the tech. line when it comes to my cams, but I run this cam in my 1972 Challenger and I have been real happy with it. I is an old style Pro-Street tubed and frame tied 727 with 3000 rpm stall, 904 with 2.14/1.81 with very little work done on them (clean up). Comp cam 21-232-4 RPM Range 2500-6500 .520/.540 lift Duration 282/290 @50 244/252 Solid lift. I think your LY’s with harden bolds would be fine for your rods. I was told once that if you are building a big block mopar you need to do pay attention to three areas, rotating weight (Stock pistons 857.5 grams / JE piston 613 grams = 1956 gram weight loss, 1lb is 453 grams that is taking off 4.5 pounds off the rotating assembly). Heads (he said for high HP aftermarket heads only), and cam selection (self-explanatory). He seems to right for the most part, but I do know I have seen some very fast stock headed mopars so I guess you will have to weigh the cost of the heads rebuilt vs new or good used. I do agree with 70aarcuda on the gear choice, it is a bit deep, 4.30 with 29 to 32’s on the tires would be much better. Good luck and let us know how you do
 
Well I can tell you what I ran a long time ago for reference only.......

3000lb all in '69 Cuda race only, heavy stock 440SP bottom end, the CC .290@.050 dur solid flat cam at approx 10.1, we had 98 fuel so ran it at 38 deg total, 4200 verter, idled real smooth at around 900rpm, 4.88's >32" tyres, (I liked to 60 well) we ran an 850DP, ran stock 2.08/1.74 906 heads to begin with, that ran 11.23/118 turning around 6200 through the traps, added nothing else but mildly ported 906's with 2.14/1.81's and went 10.7/125 at 6500 trap. That cam is not supposed to work well with anything but 12.1 comp which I should've run with 98ron, but boy did that car pull at the top end which is what I wanted, whether that might be a bit too much duration for the occasional street outing with a 3500 verter I don't know, but it sure worked at the track and ran real strong, wouldn't think I had a lot of cranking compression with such a late closing intake valve and 10:1 scr (motor only made 485 track hp) but thats exactly what you don't need, high psi on 92 octane and iron heads.
 
1. Why iron heads? so much better heads available..
2. 1/8 mile or 1/4 mile track?
3. go custom cam - do not waste time with an off the shelf cam IMO
 
70aarcuda said:
old mp 557 cam is 258 @.050......well..after you buzz the motor..with 29 tire and 4.88 gears...I would use a 4.30 gear with 29 tall tire...
Click to expand...
Thanks Tony
AJ/FormS said:
29s and 6500;make about 115 with 4.88s, and 123 with 4.56s, and 130 with 4.30s
Click to expand...
Good post AJ. Just by the posting, it would be a better suggestion to read into it and decided exactly what you need and where you end up at.

I also have a set of 4.88's in my Duster. There great for 2 things. Light to light in this crowded town and burning rubber.

Zac, a better head choice may not be an option or desire. I just learn to work with what the poster has listed. It's just so much easier than questioning and pointing out the obvious over and over.
 
Cope, I ran your engine with a little more head with the 284/528 MPP cam and 10.5:1 KB hyper pistons. It made 467@5600 and 514@3900. That car went 11.56 in the 1/4.

You have way too much gear for that engine no matter what cam you put in it and you may find that the convertor is too low of a stall.

I have 4.56 gears in my latest car and trap at 6200 but the engine which is more stout the former car peaks hp at 5700 and peaks torque at 3500. That's with a 28" tire.

I'd think 4.10's or 4.30's and a 28+ tire. 3500-4,000 stall is likely where you'll end up but you won't know until you dyno the engine. If you are going to guess go 4,000 on the stall.
 
Thanks Rocco.

I dont even have the rear end housing yet so rear gear is up in the air.

I do some what have access to a dyno. Its not ours but a little cash will get me time on it and the owner is a great builder.



with your guys feed back im leaning tward 4.30 rear gear.
Thanks again for all the time and advice.
 
You'll be happier all around with the 4.30

If you don't have the rear I'd be forced to give a heavy nod to a Dana.

Engine dyno time is worth it's weight in gold.
 
JE pistons? Seriously? The hell you say. Do your budget a favor and put the Speed Pro forged six pack piston in it and be done with it.
 
roccodart440 said:
Are they heavy like the stock 6 pack pistons?
Click to expand...

What difference does it make? How many millions os stock "heavy" six pack pistons do you think have raced through the years JUST FINE?

You're splittin hairs.
 
I guess, If I had a complete engine that I could race, sure, I'd use them. But they wouldn't' go in my engine if I was buying new pistons.
 
RustyRatRod said:
What difference does it make? How many millions os stock "heavy" six pack pistons do you think have raced through the years JUST FINE?

You're splittin hairs.
Click to expand...

Well mine for one, did 2 seasons no probs, even turned 7300rpm with N20 and no issues but didn't fancy doing that too many times, the motor sang a bit top end if you know what I mean....... Also I had enough PTV clearance with those slugs (900gms) with that .650/290@.50 solid and fel-pro blues, didn't have to cut the pistons, we didn't measure the heights though. My old 1968 Block is still running today 25yrs after in an Anglia with a smaller cam of course...did have external oiling.
 
(Quote: RustyRatRod – JE pistons? Seriously? The hell you say. Do your budget a favor and put the Speed Pro forged six pack piston in it and be done with it.)

Great statement by MOPER we always just assume we are running engines at sea level, but I know you will lose ½ to 1 full sec. in Denver so I think that is a great point. As for pistons and rods yes there are /and have been lots of cars racing with six pack rods and pistons but there has been many who have come apart too. RustRatRod makes a good point, it all comes down to what you are doing in those hole, Nitrous, high compression and so on. Chambers: open, closed, heart shape, and valve size. Here is the draw back with the 6-6 idea the last stock ones were made 45 years ago and most people who ran them ran them hard or they wouldn’t be apart and for sale. The stock 6-P Pistons: you would have to change the pins and locks, they takes wide rings both Speed Pro and stock and they are both heavy, real heavy, and with the stock ones you have to have a block with a very straight STD bore. The Speed Pro forged six pack piston is a good piston (Depending on the head chamber) but it’s not a true forged piston, it uses a lot of Silcom, but they do have a good price. At a minimum with stock 6-P rods they would have to be magnafluxed, polish beams (to stop cracking), check and maybe replace the bushings, and change the rod bolts about $150 to $300 worth of work. Or just buy a set of I-Beam eagle rods for $250 or H-Beams for $450 to $600. If it is a mechanical motor (NOS less than 100hp) then I beams: Eagle, Mopar LY, Good Six pack rods will be fine and almost any piston will be OK: Stock, Speed Pro, KB, JE, Ross, Seal Power just watch the weight. If there is NOS involved there are two routes to take with rods and pistons. Pistons - as little silicone as posable in the Piston is the rule, 150hp NOS or more forged pistons are recommended. Rods: 150hp NOS or more you have two paths to take. Strong or absorbing, what I mean is H-Beam (Strong and heavy) Aluminum (Absorbing and light), it’s all up to you and your budget.
 
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