Low compression 440 dyno test

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Babyblue66

Babyblue66

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I did this last winter and I thought some of you may find it interesting.
I had a 77 440 highway patrol motor I ran the crap out of in the 90s. Last winter I took it apart to freshen it and swap the cam. I reused the bearings since the crank was reground in 1998 because I spun a rod bearing at over 120 mph.
Back then I ported the heads so I did a little more work on the 452s and put in some new Elgin valves along with a Serdi seat cut. Also cut the guides for Viton seals. I installed the Hughes 2942 whiplash cam, degreed it, and set up my old Mopar performance springs. New comp retainers too. I ball honed the cylinders and installed new rings on the factory pistons. With these smog pistons it cc'd out to 7.5 to 1 compression. Topped it with an old CH4B and a 3310 holley 750. I was guessing 350hp.
To my surprise the old turd cranked out 415 hp and 462 ft lbs!
 
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A few pics.

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Yeah, Jim Laroy (@IQ52) did some low compression runs on a couple of big blocks and got quite good results. Low compression doesn't mean dog. Yours is makin pretty good power.
 
Obviously lost power with manifolds, but my headers were junk and this was easier. It pulls really well with a stock 383 magnum torque converter. Flashes to around 2700.
Set up the Mopar performance distributor to 22 degrees initial and 38 total. Lots of initial timing is key with this cam and low compression. It's very responsive. Nice lopey idle.

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Babyblue66 said:
Obviously lost power with manifolds, but my headers were junk and this was easier. It pulls really well with a stock 383 magnum torque converter. Flashes to around 2700.
Set up the Mopar performance distributor to 22 degrees initial and 38 total. Lots of initial timing is key with this cam and low compression. It's very responsive. Nice lopey idle.

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I have this almost same combo in my Gran Coupe. My timing specs are dead on with yours. 37 all in. Mine is a little lower on compression probably. Uncut 452s and thick MR. Gasket head gaskets. Thanks for sharing!
 
408 swinger said:
I have this almost same combo in my Gran Coupe. My timing specs are dead on with yours. 37 all in. Mine is a little lower on compression probably. Uncut 452s and thick MR. Gasket head gaskets. Thanks for sharing!
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I'm not sure when they went to the dished piston. I had a 73 440 and they were flat top. The dished motor would be about 7.2 with a felpro.
 
The cam is surprisingly nice driving as well. It smoothes out just off idle. With an electric choke and one heat crossover open in the intake, it warms up quick and runs really nice. My tranny is a newer one with part throttle kick down, so with just a little pedal it drops a gear and the torque is right there. Im happy with it for being an inexpensive engine and somewhat of an experiment.
 
I have a similar long block. I tried a Holley 750vs and a Edelbrock 440 Torker and later a 850dp on the same intake. Hands down, seat of the pants, the current Weiand tunnel ram with 660's out performs them both. I wonder now, what kind of power I am making. Thank you very much for sharing!!
 
71GSSDemon said:
I have a similar long block. I tried a Holley 750vs and a Edelbrock 440 Torker and later a 850dp on the same intake. Hands down, seat of the pants, the current Weiand tunnel ram with 660's out performs them both. I wonder now, what kind of power I am making. Thank you very much for sharing!!
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I tried a torker, much less torque under 4500 rpm than the dual plane. Tunnel rams run great. I have one too, it was on a 9.5 to 1 440 I built years ago. I'm sure it'd run well on this current engine too.
 
Babyblue66 said:
I tried a torker, much less torque under 4500 rpm than the dual plane. Tunnel rams run great. I have one too, it was on a 9.5 to 1 440 I built years ago. I'm sure it'd run well on this current engine too.
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Is this your dyno? Or were you at a shop? Would there be an opportunity to test the tunnel ram? Hate to hijack this, but curious

edit** I missed you did this last year
 
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Just curious. Have you put a compression tester on it to see cylinder pressure? Not that it matters, because with good dyno numbers and I'm sure it puts a smile on your face, that's all that matters. I'm just curious if those Whiplash cams do "optimize" cylinder pressure like they claim. ....but again, it's makin the power, so what's the difference?
 
RustyRatRod said:
Just curious. Have you put a compression tester on it to see cylinder pressure? Not that it matters, because with good dyno numbers and I'm sure it puts a smile on your face, that's all that matters. I'm just curious if those Whiplash cams do "optimize" cylinder pressure like they claim. ....but again, it's makin the power, so what's the difference?
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I planned to, because I'm curious also. Just never got around to it.
 
Babyblue66 said:
I'm not sure when they went to the dished piston. I had a 73 440 and they were flat top. The dished motor would be about 7.2 with a felpro.
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I don't think 440 ever had a dish piston. I just commented on mine being lower compression because of uncut head and thick gasket. Again, thanks for sharing! There's hope for my slug yet.
 
Learn something new everyday. All the ones I have taken apart have been flat. 73 through 78.
 
408 swinger said:
I don't think 440 ever had a dish piston. I just commented on mine being lower compression because of uncut head and thick gasket. Again, thanks for sharing! There's hope for my slug yet.
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Yes they sure did. This is the engine before I freshened it. As you can see it has a . 045 dish.
 
I have some 440 pistons that have a huge dish, probably 1/4". They are early, pre-1972. Maybe industrial or marine?
 
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