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Jack Leslie's 1957 Sedan Delivery

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It's Peanutbutter Jelly time!

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:D Yep, it's time to do the dance. :angry:

My friend Mac came and took some pics and video for me. Gotta say thanks for that, since I no longer have access to a video camera. This vid is of the 317 run I believe. The sound cut out for a bit on the 319 run, and the mic was definitely past the clipping point on the run with the cutout open.

First couple pulls it was cutting out early for some reason. Ended up being a top speed limiter in place with the gear selector in 3. No idea why it was set to that, since it didn't do that last time I dyno'd, but I changed it and it then pulled all the way to 6400rpm.

First pull iirc was in the 315whp range, 292 ft/lbs torque. Dropped the commanded AFR from 12.2 down to 11.8 and pulled a bit of timing at the top where I was getting 2-3 degrees of KR. Went up to 319 and 295. AFR's weren't going down so I stopped adding fuel. Was still getting some KR so took out a bit more timing, and got 317 and same torque at 295. Made the last run with the exhaust cutout open and got 320whp and 300 ft/lbs. ! Might have been a tiny bit more if I was using the timing map from the 319 run, not sure. But at least I know the cutout open is good for about 3whp and 5ft/lbs when I'm running at the track. :( That is versus pushing it through the high flow cat and rest of the exhaust.


In my scans I hit 11.6:1 AFR at one point in the middle of my rpm band, but by 6000rpm it was back to 12.2 and all the way up to 12.6:1 at redline. Injector pulse width hit 21ms at 5600rpm and stayed there all the way to 6400.

I think that's pretty solid evidence the 36lb GTP injectors are maxed now. They are only good for about 300whp tops. 320whp is about 390 at the crank. According to the math on RC engineerings site, six 36lb injectors at 60psi fuel pressure and running a BSFC of 0.55 will only make 390hp running at 85% duty cycle. Definitely maxed for a pintle style injector. I need disc types again, and bigger flow rate. I should have held on to the Lucas 42lb injectors I had! :wacko:

Also I noticed intake temps were nice and cool at the start of the runs... it was 64 degrees and 26% humidity today (awesome!).... but got up in the 90's by the end of the pull. I've seen 100 on an 80 degree day. Pretty evident this car needs either an intercooler or alcohol injection now. Timing at redline was 14-16 degrees depending on what the knock sensor was doing. I'm not going to be able to add timing back until I can cool that air charge off.

I'd like to get some bigger injectors and go with a methanol/water injection kit from either snow performance or devils own, since they both offer progressive injection controllers that can be activated at a set boost point. And I'd get the added fuel and octane from the alcohol at higher boost levels without having to resort to such low commanded AFR's all the time (which kills my O2 sensor faster). So that's the eventual plan. Money's short though so it's going to have to wait. Plus I'm moving soon and don't know if I'll even have a place at home to work on the car myself after I move, so it might be a while before that happens.

For now, I want to head to the track in a couple weeks and see if I can get some new times. Been three years since I ran and I might not be able to again for a while. Going to throw a few gallons of 100 octane in the tank and see if that will help the last 2 degrees of KR I can't get rid of. Then I'll probably drop back to a 2.5" pulley again for now to save gas and wear and tear on the SC, until I have the $ for some of the mods I'd like to do.

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