It's been about a year and half since I first ran this on the dyno.

I've had a bit of time for revisions since someone rear ended me at 40mph on the way home. Car is all fixed and completely repainted now, better than ever.

Basic combo is-

.060 over 426 so about 438ci.

MP iron block, CP pistons, 12.4-1 .043 rings. GZ vacuum pump

MP iron heads (I ported them)

Cam motion low lash solid roller 262/262 112lsa, .658 .612 measured at the valve. Morel black mamba lifters. Trend tapered pushrods. PSI 1.4" OD valvesprings with TI locks and retainers.

Holley HP efi. Edelbrock dual 4 intake, ported. 80lb deka injectors, Flex fuel

TTi 2.125 headers into dual 3" exhaust, pypes race pro mufflers out to stock style tips.



So here were the revisions between the overlayed graphs.

Added HVH 1/2" spacers under the throttle bodies

Changed stock diameter lower pulley to ASP underdrive (it was blowing belts into low earth orbit) Way too much pulley ratio for the rpm.

Switched from 20w-50 Brad Penn to 5w-30 Royal Purple XPR. Also changed to synthetic trans and diff fluid.

Rebuilt tailpipes (they got smashed) with the largest radius bends I could fit.

Last thing that I'm sure made a difference to the results was removing 15x10 steel wheels and replaced with W23-ish 15x10 aluminum wheels.

Made quite a difference! Feels awesome on the street.

VERY cool !!!!!!!

And I love the car, too.

Yes….that is gorgeous!!!

Did you find the true peak HP RPM?
It sounded like itw as till pulling well when he back out of the throttle?
I try to find peak HP RPM and take it form 300 to 500 RPM above that to make sure the motor hasn't nosed over and then got a second breath, which I have seen more than once

Thanks guys

Cab, it seems it peaked at 7250. It doesn't nose over hard after that but the rev limiter is set to 7650 due to driveshaft critical speed. (so pulled to limiter was about 400rpm past peak)

I could put a carbon driveshaft in it and test higher but doubt it would do anything but continue to gradually fall off. And..I think may be hard on the valvesprings and valvetrain overall if I push it to/through instability with a 2.25 steel valve.

Fwiw, the changes made were of course small but seemed to add up. When I ran it in initially and it threw belts I noticed a jump in power. Seeing that and the numbers now, I think a big part of the difference was the underdrive pulley.

Additionally

While I tried my best during the first dyno session, I was fighting belt issues/tossing belts.


Today, with the underdrive pulley and having no belt issues I was able to experiment a bit with timing.

The best numbers were achieved with 29deg total timing.

It would take 33deg (and more) no problem but would drop 10+rwhp in the process.


Fwiw, max power achieved at 29deg total was within 2hp at 35% alcohol and 70% alcohol.


Maybe I went to far. Basically what I'm trying to say, or what my observations are is-


-Total timing ended up lower than I expected.

-The above observation didn't change with additional alcohol. Still made the most power at 29deg regardless of alcohol content.

-Lastly, to the points above, yes I verified timing from idle to high rpm. (What is commanded is actual)

Very good returns for the changes made. Congratulations,and keep it between the ditches.👍

Nice A$$ car was this video made before or after the accident.?

She's a beauty.

Beautiful car, should be a hoot to drive too.

Seems like a lot of power for that combo. You did good.

Well done Sir, enjoy!

I couldn't keep a belt on my hemi. It would toss the belt the minute I hit the gas until I changed to a Dayco Top Cog belt and now I haven't thrown one even up to 7,500 rpm in over ten years. No other changes.


Mike

Thanks guys! Will try to keep it between ditches Dyno video and this one were made yesterday so after the accident.

there is no better sensation (maybe there are, in the bedroom ) than having enough power to break the rear tires loose at speed
The trick is knowing when and how to drive it correctly, so you don't hurt the motor, car and yourself Be safe, have fun


Do you have your shift lights hooked up to the two hood turn signal lights?

very impressive indeed !
i wished my charger was 1/2 as nice as yours !

Thanks guys! It was pretty cold yesterday but I think when it warms up a bit the Avon CR6ZZ's will hook fairly decent. (road race tire with 80 treadwear rating)

Cab, yes I wired in a relay so the hood lights function with the turn signals and also as a shift light from a Holley EFI output

Nice car. Good power. I like the shift lights.
Doug

I had a 484 hemi years ago....The little monster made 500hp & 500 torque to the tires with a little .630 roller cam. It was a lot of fun on tires.