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Budget build

69greenleaf

69greenleaf

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hello all. I have a 69 2dr sattelite with a late 70s low compression 440. Motor is fresh rebuilt with stock lower end and heads, only after market parts are a edelbrock 1407, long tube headers and a hot ignition system. I have e been looking to make a budget racer out of the car. Currently building a 4:10 spool 3rd member, though the car has the over drive 4-speed which will render 1st gear useless . Anyhow, I have been looking into raising the compression without having to tear into the lower end. I have read the piston are around .080-.115 in the hole, which is way to far to get the block decked. So what would be my best option to bring compression up. Way smaller cc heads and cam? Or would it be worth is to save the money on 6-pack pistons to get rid of that awful compression height?
 
To deck the block for a shorter height would require full disassembly, so at this point, a possible rebuild is in order but I would not get “6 pack pistons” but rather a set of Hyper U slugs instead. Healer than forged but still strong. If only a forged slug will do, look at the modern offerings.

Smaller cc chambered heads would help a lot but I’m not sure of all the math and where you would end up. We all would need to know exactly how far down the hole the slugs are to start.
 
Oh, careful cam timing will increase the dynamic compression some but not really a whole lot is added. It is best to work on the static ratio first. Get your ratio where you want or need it to be. This works in conjunction with a he cam to be used.

What is the goal of the car et wise?
Do you have a particular head for the future you want to run?
 
1. A very low overlap cam will help your dynamic compression.
2. Closed chambered heads, with the smallest combustion chamber possible will help your static compression.
3. Thin, factory, steel shim head gaskets at .020" compression thickness will help static compression (though not good for aluminum heads I hear).
4. If you plan to run a spool, make sure this is a track-only car. Turning corners on the street + spools don't mix.

So, on your overdrive transmission...... is that one of those "granny low 1st gear" transmissions? I rode in a 318(?) delivery van that had one of those & the guy just took off in 2nd gear... OR, do you have 4th gear = overdrive?
 
PurpleBeeper said:
1. A very low overlap cam will help your dynamic compression.
2. Closed chambered heads, with the smallest combustion chamber possible will help your static compression.
3. Thin, factory, steel shim head gaskets at .020" compression thickness will help static compression (though not good for aluminum heads I hear).
4. If you plan to run a spool, make sure this is a track-only car. Turning corners on the street + spools don't mix.

So, on your overdrive transmission...... is that one of those "granny low 1st gear" transmissions? I rode in a 318(?) delivery van that had one of those & the guy just took off in 2nd gear... OR, do you have 4th gear = overdrive?
Click to expand...
4th is .70:1 I believe. The spool is just a temporary fix until I have the money for a sure grip unit.
 
69greenleaf said:
4th is .70:1 I believe. The spool is just a temporary fix until I have the money for a sure grip unit.
Click to expand...
If you can shift quick enough, I think you'll still be using 1st gear at the track with 4.10's...... at least with 3.91's I'm still using first gear.
 
rumblefish360 said:
Oh, careful cam timing will increase the dynamic compression some but not really a whole lot is added. It is best to work on the static ratio first. Get your ratio where you want or need it to be. This works in conjunction with a he cam to be used.

What is the goal of the car et wise?
Do you have a particular head for the future you want to run?
Click to expand...
I would like to have it at low 12’s. I am just starting to try and get into racing so I don’t know what exactly would get me there. I know the transmission I have is not ideal. And I know I need to ditch the open diff and low ratio in the rear end. I was looking at a set of e-street 5090 heads 75ccdome for around 1100. But I can’t find anything on the stock head cc
 
The exact current head identification would be in order. If it is indeed truly stock, then the exact year of the 440 is needed.
 
Aluminum head heat transfer equals approximately 1 point in compression drop so cc gain from e street chambers may be cancelled out. The Hughes whiplash Cam is made for what you are doing.
 
Is your rear end an 8 3/4? If it were me I wouldn't be running a spool with 30 spline axles behind a 4 speed.
 
There's a good thread from over at dodgecharger where heyoldguy (IQ52?) did a few dyno runs on a low compression 440 to see how much power each mod gained. It's a good read and goes to show these low comp motors can still put those cubes to work. The quick and dirty on it: he made 450 lb-ft and 387 HP keeping it at 7.8:1 then changed to ported 516 heads and got 473tq/449hp.

http://www.dodgecharger.com/forum/index.php/topic,104749.0.html
 
Last edited:
ChargerM440 said:
There's a good thread from over at dodgecharger where heyoldguy (IQ52?) did a few dyno runs on a low compression 440 to see how much power each mod gained. It's a good read and goes to show these low comp motors can still put those cubes to work. The quick and dirty on it: he made 463 lb-ft and 440 HP keeping it at 7.8:1 then changed to ported 516 heads and got 473tq/449hp.

http://www.dodgecharger.com/forum/index.php/topic,104749.0.html
Click to expand...
Small correction. The cylinder head change took us from 387 HP to 449 HP. Torque from 450 to 473.
 
Car Craft or Hot Rod did the aluminum vs iron challenge and found no power loss anywhere.
 
There ( The aluminum head) better resisting to detonation so in effect, your not lossing but giving up that 1pt. In ratio. As I understand it. Get what you can!
 
Last edited:
69greenleaf said:
hello all. I have a 69 2dr sattelite with a late 70s low compression 440. Motor is fresh rebuilt with stock lower end and heads, only after market parts are a edelbrock 1407, long tube headers and a hot ignition system. I have e been looking to make a budget racer out of the car. Currently building a 4:10 spool 3rd member, though the car has the over drive 4-speed which will render 1st gear useless . Anyhow, I have been looking into raising the compression without having to tear into the lower end. I have read the piston are around .080-.115 in the hole, which is way to far to get the block decked. So what would be my best option to bring compression up. Way smaller cc heads and cam? Or would it be worth is to save the money on 6-pack pistons to get rid of that awful compression height?
Click to expand...

Who cares about compression, it's not worth tearing a good engine down. You're not losing enough to actually make a significant difference. Mopar performance ran faster with every single camshaft upgrade in their test Duster, from the .509 Hydraulic to .590 SFT in a low-compression 400 low-deck.

Wallace calculator:
http://www.wallaceracing.com/hp-cr-chg.php

Great article on HP/per point compression:
http://www.hotrod.com/articles/0311em-power-squeeze/

I would run the .528 MP SFT w/ factory heads (find a used set of ductile iron rockers). Electric fan. Aluminum radiator. 160* thermostat. Remove the rear seat. Relocate battery. 3" exhaust - dynomax bullets w/ simple turndowns (well before rear axle, less tubing = less weight). 4.10 spool. 28" drag radials, with the lightest 8" rear wheels you can find, of course, 4.5" wheels on the front w/ inexpensive VW tires. 34-36* total timing on pump gas. Fiberglass front / rear bumpers. Remove all the interior insulation. 2" intake spacer to add more plenum volume. A good set of 90/10 shocks for the front.

Keep it simple and inexpensive. Build your true bracket racing engine on the stand while this one is in the car.
 
Last edited:
That was a actual 9.0-1 big block 400 MP used and not the lower than 8.0-1 run of the day 440 of the late 70’s.
 
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