Drag Strip tips and advice needed.

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I will post my results in the morning. Not sure what else to do at this point.
 
Don't know who Richard is.. is he a racer? Familiar with BB mopars?
Give it more fuel, get total timing to 38° and leave just off idle and at 150° water temp.
 
Kent mosby said:
I took my 73 scamp to the drag strip a few weeks ago. It has a 512 RB with Super sniper EFI. I mistakenly did not have the Closed loop and learning on at all before I took it there and during the races and my times were underwhelming. 13.4 at 104 best. I subsequently had a tune done remotely by Richard Nedbal and have driven the car a bit since. I have a 727 with TF2 kit and Quicksilver shifter, no line lock hooked up or transbrake. Rearend is 8 3/4 with 3.91 gears. Mickey thompson Street ss radials. 3000 rpm stall TC.

During the first 3 times down the track, the tires did not slip at all. I did not burnout as it was my first time drag racing. I also did not manually shift the car but let the transmission do the shifting. I did rev to about 2000-2500 before releasing the brake on launch. My best 60 ft was 1.97 or so.

What tips, techniques or advice should I do for the next test and tune coming up tomorrow?
Youtube has many videos on how to launch but launching a 300 hp car is different that 500 and tires make a difference. Knowing my setup, specific advice for me would be appreciated.
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What compression ratio does the 512 have? Any idea what the car weighs? Your convertor is a little tighter than if you if had a all out race car, but shouldn't be the main issue. I'm going to suspect something with fuel line/delivery or setup. Could be a partially clogged filter, not enough pressure, etc. I have no experience with EFI, but your combo should be running well into the 11's I'd think.
 
Obviously you verified the throttle blades open fully, kick down linkage not limiting wot?
 
Richard’s website is fastmanefi.com. He wrote a famous book on high performance hemis that sells on amazon. Very much a Mopar guy. We verified full throttle opening. Weight is a stock scamp with interior. Filter and tank were new. Less than 500 miles. Compression 10.3.
 
strange.....since he´s a pro, i don´t doubt there´s something wrong with the sniper. I run one on a 408 SB, car runs 11.0 @ 119 / 1.50 60ft.

What target AFR´s are you running? Can you post a picture from the timing map? Timing veryfied? Something is definitively off. Maybe timing control deactivated.

Michael
 
Sorry, I am on the golf course now. I will post after the races . I will not have time to change much
 
Kent, you said that you have a 6AN fuel line. IMHO I think that's too small to feed a 512 under full throttle. Thing is...with a carb and too small of a fuel line it will run fine until the fuel runs out in the carb, but with FI I'm not sure how it would act. Maybe, because there's no fuel reservoir with FI, the engine would be soft all throughout the run, not just at the end?
 
The line is 8an up to the engine bay and then there is an adapter reducing to 6an for about 3 feet. If that is a problem, then I can change that. Can I data log the fuel pressure for the runs as well as the other parameters?
 
Kent mosby said:
The line is 8an up to the engine bay and then there is an adapter reducing to 6an for about 3 feet. If that is a problem, then I can change that. Can I data log the fuel pressure for the runs as well as the other parameters?
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You can data log just about anything. I would look at the plugs and see if it's running lean or if you have info from the O2 sensors. That will tell you. 8AN necked down to 6AN would still give you a pretty good restriction. Pressure might be good but that's for the injectors to run right. What the engine needs is fuel volume at the right pressure.
 
Kent mosby said:
The line is 8an up to the engine bay and then there is an adapter reducing to 6an for about 3 feet. If that is a problem, then I can change that. Can I data log the fuel pressure for the runs as well as the other parameters?
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Yes. U should be able to turn on the log feature and see everything. Although, I'm not positive on fuel pressure. I know the FItech you cannot log fuel pressure. There isn't anything to monitor it. You could run an electric fuel pressure gauge inside the cab.

I would also get a real tach.
 
That car should MPH in the 115+ range without much issue and actually probably in excess of 120. Something is off.

If the fuel pressure is like most other FI setups 40+, the -6 line likely isn't going to be an issue.

Don't recall the build, but shift it manually in the 5200-6000 range and see what it does. I'd be more concerned with MPH than ET right now. You can work on different launch techniques, but, the MPH is not up to snuff.
 
Ok, I just got back from the golf course. I checked the TPS on the EFI. I could only open it 57% with the pedal at the floor. Doh. What an idiot!!! I previously got the rpms up to 5800 or so and wondered why it did not have more. I guess there is more. I adjusted the throttle cable (there was slack) and cut a bit of the carpet out. Now at least I am at 87%. I will try where it is tonight, datalog all the races and post tomorrow.

plumkrazee70 said:
Yes. U should be able to turn on the log feature and see everything. Although, I'm not positive on fuel pressure. I know the FItech you cannot log fuel pressure. There isn't anything to monitor it. You could run an electric fuel pressure gauge inside the cab.

I would also get a real tach.
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. What tach do you recommend? I have never looked at them.
 
Kent mosby said:
Ok, I just got back from the golf course. I checked the TPS on the EFI. I could only open it 57% with the pedal at the floor. Doh. What an idiot!!! I previously got the rpms up to 5800 or so and wondered why it did not have more. I guess there is more. I adjusted the throttle cable (there was slack) and cut a bit of the carpet out. Now at least I am at 87%. I will try where it is tonight, datalog all the races and post tomorrow.

. What tach do you recommend? I have never looked at them.
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Also, try adjusting the cable while at full throttle and see if it will go back to the fully closed position.
 
Meet your next problem:
E3A1F1D6-3989-4F17-AE9E-DA0AE7DD4673.jpeg
 
I'm not trying to be judgmental, and i guess i am...BUT....why didn't your tuner guy catch that.
I guess he was focused on fuel ratio, not fuel/air volume.................
 
Kent mosby said:
Ok, I just got back from the golf course. I checked the TPS on the EFI. I could only open it 57% with the pedal at the floor. Doh. What an idiot!!! I previously got the rpms up to 5800 or so and wondered why it did not have more. I guess there is more. I adjusted the throttle cable (there was slack) and cut a bit of the carpet out. Now at least I am at 87%. I will try where it is tonight, datalog all the races and post tomorrow.

. What tach do you recommend? I have never looked at them.
Click to expand...
I believe you found the missing HP.
 
The tuner was remotely connected and did not see the setup.
 
Well, The night did not go as planned. I got 3 runs in very quickly. 30 minutes. Horrible results. 14.0 best, 14.7 worst. The car did not have any umph at all. my son running next to me said my exhaust was blowing out lots of smoke. After I got home I looked at the clamp on O2 sensor. Tons of black soot all around it and the connection just 8 inches after it. It makes me think that the EFI was trying to get the A/F ratio correct and the sensor was not getting the correct info to adjust the fuel properly. So I have to weld the sensor on and get rid of the clamps. I will also pull some plugs and check them to see if my suspicion of overly rich is correct. After the thid run as I was pulling into the pits to take it home there was some popping from the exhaust. Then after I got home as I was pulling it into the shop, there was more and bigger popping from the exhaust. Unfortunately, the data-logging did not work.
Also the exhaust tips are sooty. I will pull the plugs tomorrow.
 
Welding it is a good idea
how much exhaust pipe, have you got past the o2 sensor?
I think you need to have a conversation with your tuner and see what his suggestions are

I agree that if that o2 sensor clamp was allowing air in (not sealed). The computer would be seeing lean, no matter how much black smoke was coming out the pipe.
 
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