Getting the most out of a low comp 440

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RustyRatRod said:
I'll swap you my Coronet for it. lol
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Has a '68 318 and 727, unknown mileage. 9mpg if I drive it hard, 11easy driving. Leaks and smokes, but it runs. Doesn't make much power, but the power curve feels good for what it is. Pulls from the bottom up to 4500.

I like to rev stuff a bit...what's a stock 440 bottom end good for?
 
RustyRatRod said:
Mopar has not held the heads I have. They were milled according to Don Dulmage's book. They were milled so much that they felt fragile. Because they WERE. I think they had been milled approaching 1/4" if I remember right.
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I want that dang book!

Did he die? Can't get ahold of him.

Call me dense, but I don't exactly follow what you're saying. Mopar hasn't held them?

I've heard of 452s being miller up to .120". I won't likely go that far.
 
DavidWymore said:
Has a '68 318 and 727, unknown mileage. 9mpg if I drive it hard, 11easy driving. Leaks and smokes, but it runs. Doesn't make much power, but the power curve feels good for what it is. Pulls from the bottom up to 4500.

I like to rev stuff a bit...what's a stock 440 bottom end good for?
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Probably 6500 with the right cam, lifters and springs.
 
DavidWymore said:
I want that dang book!

Did he die? Can't get ahold of him.

Call me dense, but I don't exactly follow what you're saying. Mopar hasn't held them?

I've heard of 452s being miller up to .120". I won't likely go that far.
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I mean if Mopar says .060" is the limit, they ain't seen what other folks have done. lol
 
Gotcha...forgot to mention, truck will spend most of it's life BELOW sea level. When it goes over the mountains, I can put higher octane in it.
 
DavidWymore said:
Rb, any idea what valves and how many ccs they are?
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All stock 2.08 int and 1.60 ext I think thats right and maybe 10-15 thousands milled off from bottom side so cc's guessing 83-85 cc someone else can chime in here I forgot what the 516's cc were stock,they should raise your comp about 1/2 point right off the bat..milling them would increase it more,prob have some good 2.08 and 1.74's around that would work or best to prob buy new ones but i have some, you would just have to regrind them and bore out the exh seats but hey u work in a mach shop,unless you port them good better off stay with the 2.08/1.74 for more torque on bottom end,you can put 2.14/1.81's but it is close,but if you open up the heads to breath good then hence the bigger valves..and many will have pros and cons about these heads but I have used them many times even with the smallish 1.60 exh...I've always felt these heads[516's] were capable of some decent perf with a little work..
 
Say ur comp now is 7.8... 516's should bump it up about half a point,so 8.3...mill heads I think .060 should raise it a full point to 9.3 roughly..RUSTY u wanna chime in here am I close on these figures?
 
DavidWymore said:
http://www.csgnetwork.com/compcalc.html

If I got taller pistons, they're heavier, right? So then I have to re-balance? I have a precision digital scale at work...can I lighten the taller pistons on the inside somehow? Polish the rods down a little overall to lighten?
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Maybe just have to chk...wouldnt have to rebalance but would be a good idea....and yes on the lightning of the pistons and rods which would be part of rebalancing...
 
Have to worry about the total bob weight,then adjust the crank to match. Not cheap,especially with a possible cast crank setup.(figure 2 to 4 bills).
 
I'm cast. Heavier recip parts = more weight = Mallory = $$$ by the time I get done boring, buying pistons, balancing. Crap.

Is there a chance there is a stock bore piston that is taller but weighs the same as the stock piston?
 
Need to measure deck height, not necessarily piston to deck. Over thinking,fix what you have. 440's are a different animal,from any other mill.(google Hot Rod magazines"Cheap Thrills" articles,1994....).
 
Here's what I'm currently smokin'. I may be leaning a little toward the high RPM side for a 4k vehicle, but I can't stand engines that run out of breath too soon. A lot of this is influenced by QuickD100, who ran lowbuck 440s bout like this in a truck into the 12s, and IQ52's low comp dyno test...but with a little CR to keep some low end pop.

Seems like the consensus is the stock bottom end is good for 450hp and 6500 RPM. Prolly oughta balance it if I'm gonna wind it. :banghead:

850Tquad (What I have, and a good carb guy)

Intake = MoPerf dual plane Idle - 6000


Cam = MP .509 with Rhoads lifters ???-6000
Or maybe a milder cam with 1.6 rockers? Less duration, more lift? Or Comp XE275HL. If I understand correctly, the heads flow to ~ .500, so should shoot for that much lift?

Don't know what springs I'd need for the .509 and 6kRPM

Heads - clean up per Mopar Muscle head articles (been reading the heck out of them). Maybe bigger valves? This is where I get fuzzy. How much HP/RPM will the stock heads support configured as such?

Adjustable timing set...advance "big" cam if necessary for bottom end.

Approx 9.5:1 CR with .020" gasket, adjust with thicker gasket if necessary for 87 octane. Undecided on pistons or lopping ~.100" off heads...after CCing, measuring everything. Not liking buying pistons, having to bore, balance...but there is that one bore that's pretty bad. :banghead:

I have 1-3/4" into 3" long tube headers.

~2,500 RPM stall converter (or a smaller cam and existing moho 'verter)

4.10 or 4.56 locked Dana 60

29" tall 7" wide tires...may look into something bigger and stickier although hopefully building the engine a little on the high RPM side will cut down on the tire smoke...not that it'll likely get drag raced.

Auxiliary OD trans for the hiways

Thanks y'all. I been reading my little heart out and taking notes, I think I'm getting there.
 
rbdart said:
Say ur comp now is 7.8... 516's should bump it up about half a point,so 8.3...mill heads I think .060 should raise it a full point to 9.3 roughly..RUSTY u wanna chime in here am I close on these figures?
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I think the low compression 440 build Jim did started at 7.45 with open chamber and ended up with 7.85 with the 516s, so your estimate is about right.
 
Out of Dave's stuff: Looks really good,other than the camshaft. You got gears and tire,that's huge. I'm thinking something around 230@.050 (think the .484 grind,AND Rhoades lifters) Rhoad's lifters,extend both ends of the power band,adjusted correctly.
 
Went and played with RPM and 1/4 ET calcs. 400 hp = 12.xx 106 mph. 4.56 puts me at 5xxx Rpm at 100 mph

Played with camquest.com, discovered dyno simulator. Wow, cool!

Ported heads with bigger valves, 9.5:1, intake, headers, yadda yadda, and the XE275HL 479hp 5xx tq. Weee!
 
Indeed,trks can get squirrelly real fast,and you might weigh the beast to see you actual weight I'm guessing around 36-3700 lbs..I see big wide sticky tires and a battery relocation and for starters..springs,shocks maybe a 300lb fat chick in the bed...
 
With Jim's low compression build, there's really no reason to get compression to 9:1 or greater if it is a street car. It'll make power. Compression is just one small part of the puzzle. You can make up for it with head work. Some say low compression engines are not as responsive. That's just not true. As long as the parts are matched well it will respond very nicely.
 
RustyRatRod said:
With Jim's low compression build, there's really no reason to get compression to 9:1 or greater if it is a street car. It'll make power. Compression is just one small part of the puzzle. You can make up for it with head work. Some say low compression engines are not as responsive. That's just not true. As long as the parts are matched well it will respond very nicely.
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True story...not trying to make 500+ hp so you are correct..9-1 would be just fine..have seen a 440 with 8.69 comp and a 562-300 solid cam work good on pump gas,had ported/milled 906's[77cc]...030..2266 pistons .154 in the hole,team g intake 850 dp in a 69 4spd dart with 4.10's and driving normal got 10mpg on 89 pump gas very responsive and never a ping...just hard to stop...lol
 
You are going to need pistons no matter what.

The low compression 440 we built had good ring seal. It had been rebuilt with an overbore a short while back by an unknown party and all we had to do was rehone and install new rings. Worn bores, with taper and out of round, will give you an oil sucking pig. We tested a low compression 383 before we did the 440. Without rebuilding the bottom end, oil was dripping out of the breather onto the headers. So we attached 2' long 5/8 hoses to the breathers to get the oil out beyound the headers. At rpm, the blow by was so bad the hoses would stop drooping and extend out horizontally. The engine didn't make a great deal of power.

Spend the bucks for a slight overbore and install new pistons and rings. If you spend your time building this thing and it turns into bug fogger you'll be disappointed.

Plan for the future, bastardize this thing by milling .060" off the block deck, .102" off the top of the block, .100" off the heads and .197" off the intake to get everything to fit, you'll find that nothing will fit when you decide to up-grade to performance parts. Do it right the first time and this engine will out live three or four trucks. Take it from a retired pipefitter, welder and machinist.

It is however your choice to build it any way you want to.
 
Jim's got a point, and it's sharp. I'll probably do the block up right.

Also fuel tank relocation battery relocation, 200# solid steel bumper.

I'll weigh it, maybe under 4 now, 440, bigger axle, bumper, prolly push it over.

Slicks would be kool if I had a track to run 'em on. I got miles of sand to run paddles on...

Thanks y'all.
 
Man that would be a bastard care to elaborate? Had to read it about 5 times to try to wrap my mind around the concept,and I assume you really have done this or you wouldnt have posted it or are you jacking with us?
 
I think Jim was saying to use the right PISTON instead of all the milling.
 
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