How to get 500hp

[bigmanjbmopar]

I here what you are saying it just pisses me off when you spend good money on a service to find out they dint do it right. Just hate spending money twice for same thing. Thanks steve

Hey Steve, comp cams has a downloadable software program called camquest. You can plug in the numbers and parts you have and it will estimate HP.

 

[Garys1969RR]

Sounds like alot of leak down for a rebuilt engine. I would say less than 4 or 5 % max. With piston at exactly TDC, apply at least 100 PSI air pressure at spark plug hole. Then with the RADIO OFF (lol) listen at the carb, ex pipe, or oil filler hole to see where the leak comes from. Then you should be able to narrow it down to int valve, ex valve, or rings. There are so many variables in tuning a motor, everything has to be just right. Funny how 2 motors built the same can perform so differently. But I must say mid 12 s is great for a Roadrunner. Hope mine will run that good when I get the 451 finished and installed. Good luck.

 

[has2bmopar]

Iam just looking for a good solid street car and have already put a lot of money in the engine. Thanks again steve

I think you should find out what issue you have with your current investment, before you look at spending another $5,000 +. It could be something simple. I think if you fixed what you have and could drive your car you would be pretty happy with it. I still think with a little bowl work and a bit bigger cam and you will have a strong runner.

Another thing that you need to check now, that you have said that you milled large amounts off of your heads and recovered nothing back with a thicker gasket, is how much preload is on your lifters now. Also if you mill large amounts off of the face you also should take 20%+- off of the intake surface of the head as well. For a future reference you should always do your compression changes with your pistons... Compression height, dish cc's, rod length etc.

An old school fix to having too much preload is to shim up the rocker shafts, if you don't want to buy adjustable rockers and custom length pushrods. (Your preload on the baseline of the cam should be about .030"-.040") There should be some specs with your cam/lifter info.

Also, in a short amount of time you could pull the fan, shroud, pump/housing, balancer, and timing cover to check your timing chain. A multi keyway set could be confusing to your engine builder if he is as mechanically inept as you described. It is also easy to check your fuel pump pushrod.

 

[MoparBill]

I have no idea what HP I'm making but my 440 will roast the tries down to the cord if I let it - and that is with a factory iron intake and a tiny cam (MoPar .455" / 272). My first thought is you don't have 9.75:1 CR. How did you arrive at that number? A little more compression goes a long way toward making power. Certainly the cam installation could cause an issue so a double check on that may be in order as well. Pull the heads and CC the piston at TDC, the chamber as well as the compressed gasket. A cranking compression check before you pull it apart is also useful info.

My point is you don't need to spend cubic dollars to get very good performance out of 440 inches. Not sure if that means getting to your 500 HP number, but in my case I'm quite happy with whatever it does vs. how little was done to it in terms of aftermarket parts. Find out what's wrong before you throw trick aluminum parts at it.

That's some good advice right there!

 

[69 roadrunner]

Thanks for input guys. Iam running adj. rockers and custmer push rods. I know I should have milled block but was pissed off and did not want to pull motor apart again. So I took the easy way out and had heads cut. Thats when I had mach. problems becouse the mach. shop did not cut intake. So intake did not seal. I pulled heads sent heads gaskets and intake back to shop to get fixed what did they do they set up on block then cut my intake so now the intake can only run on this set up. So now you know pissed of at mach. shop. Ok now that I have a 440 that runs ok just not good low end. Iam going to take has2bmopars advise and just drive for summer then in fall tear down and inspect see if I can save some of my investment. Thanks again guys steve

 

[Garys1969RR]

Maybe you have an intake leak. The fel pro 1215 intake for hi po 440 has a blocked heat crossover passage. They also come with 4 fiber gaskets. 1 for top and bottom of valley pan gasket where it meets the heads, 2 on each side These will pretty much guanantee a leak proof seal.

 

[Cranky]

On the eddy heads I have read you still have to spend $500.00 more to get them to flow right. Thanks steve

It's not that they flow wrong. They flow pretty damn good right out of the box but they can flow better with more work. That's the way most heads are. There's always room for improvement on most parts....

Thanks for input guys. Iam running adj. rockers and custmer push rods. I know I should have milled block but was pissed off and did not want to pull motor apart again. So I took the easy way out and had heads cut. Thats when I had mach. problems becouse the mach. shop did not cut intake. So intake did not seal. I pulled heads sent heads gaskets and intake back to shop to get fixed what did they do they set up on block then cut my intake so now the intake can only run on this set up. So now you know pissed of at mach. shop. Ok now that I have a 440 that runs ok just not good low end. Iam going to take has2bmopars advise and just drive for summer then in fall tear down and inspect see if I can save some of my investment. Thanks again guys steve

I don't see how they can insure the the intake will align correctly without having the complete engine for a trial fit. There's always a factory tolerance....and nothing is an exact fit especially on stuff this old. Factory tolerances back then were out in left field someplace. On the milling part, a previous poster said compression changes should be made with pistons and not with head milling OR block milling and that's true. Milling is mainly for cleaning up the surfaces and making slight adjustments but people do it for major compression changes anyways and many times, it bites them in the butt later on.

 

[69 roadrunner]

Well it bit me in the butt. I know the intake is sealing now after sending the heads,gaskets,and intake. Then the mach. shop got a uncut block and set it up. The problem is they still just cut intake to fit. I reinstalled heads and intake it runs great checked with propane for leaks none found. I will tear down and reinspect everything and come up with a plan. Thanks steve

 

[69 roadrunner]

Guys I got a 69 440 block stock bore for free with steal crank. going with a 30 over flat top piston eddy heads ported by hughs. Perfomer rpm intake 850 carb 10.5 to 1 comp 2500 stall convertor 391 gears. What would be a good cam I have 2in headers going into 3in ex. hoping this should give me the low end i want. Thanks steve

 

[bigmanjbmopar]

Guys I got a 69 440 block stock bore for free with steal crank. going with a 30 over flat top piston eddy heads ported by hughs. Perfomer rpm intake 850 carb 10.5 to 1 comp 2500 stall convertor 391 gears. What would be a good cam I have 2in headers going into 3in ex. hoping this should give me the low end i want. Thanks steve

You got a 69 block for free??? wow lucky guy! need pictures!

Why flat tops? today's gas is bad.

Get that camquest software Comp Cams has some good deals going on now.

Also why 2500 stall just curious, My stock stall works great for low end tire ripping lol

Which carb brand? :headbang:

 

[69 roadrunner]

The motor was left at a friend shop so he gave it to me. Flat top becouse I already have them sane as convertor its already in vec. Carb going with demon. Thanks steve PS he also has a 383 if someone os looking

 

[69 roadrunner]

Bigman what part of norcal are you in Iam up in Mt Shasta ca.

 

[69 roadrunner]

bump