Went to Sac Raceway Friday night and made some nitrous passes. The suspension is working great, my best sixty foot time was 1.42. Made a few passes on a 175 shot and then stepped it up to a 225. The 175 ran pretty good but had an occasional pop out the exhaust. The 225 made it worse down track but it left the line much harder.

My best time on the 175 was 10.19 @ 132.5 with a 1.49 sixty foot. The 225 only ran 10.12 @ 132.1 but with a 1.42 sixty foot. Once I get rid of the popping it should go at least 9.90's or 9.80's on the 225, then I'll step up to a 275 shot.

Here are some pics and a video of the runs.




http://www.youtube.com/watch?v=9EEUBILZSpY

 

Very nice! Looks like a fun ride with the wheels up! Can you try to get some video next time? Maybe from behind the car? The popping could be a rich nitrous tune or maybe you need to close the plug gap down a bit. Blowing spark out could be putting raw fuel in the exhaust which then POPS..

What nitrous kit and jetting? bottle and plate pressures? What plug and what gap? total timing and timing retarded? Maybe back it up to 175 and get it running nice and clean. Goodluck next time out!

 

nice passes.

 

Nice passes, very similar to my old 355" ran 10.17@133mph on a 200shot. Sounds like too much fuel on the topside, try turning down the fuel pressure, 1/2 pound increments and check your plugs. Later Clint

 

NOS Big Shot plate with 73 nitrous, 82 fuel jets, NGK 4554 plugs gapped at .030", base timing at 38, tried pulling 5 and 6 degrees, fuel was 6 psi flowing and bottle pressure was 900.

On the 225 shot the jets were 82 nitrous, 91 fuel, pulled 7 degrees and 1,000 pound bottle pressure. Everything else was the same.

The plugs looked good but it was popping. I'm gonna try the plugs at .025" and see if that helps.

Thanks!

Not sure if you saw the link to the video?

Thanks!

I'm gonna close up the gap on the plugs first and then maybe turn the fuel pressure down a bit.

Thanks!

 

shouldnt that be a 82 nitrous and a 73 fuel ?

 

With NOS the fuel jet is bigger than the nitrous until you get up to a 350 shot.

 

Nice times. Your setup sounds wicked. Now you can update your sig with the new times. Great job.

 

The fuel pressure is @ 6lbs and we run 40psi with our LT1 EFI so the fuel jet is smaller with the higher pressure.

 

Very nice, and I love how that trans shifts. Wish mine shifted that good on the spray.

 

Thanks! Sig is updated.

Thanks! Reverse manual valve body makes a big difference.

 

I think it is too rich and an 82 jet at 1000psi is more like 300hp. If you are working from the calibrations NOS gives you, it's not surprising. Like the other big makers of kits they want you to be impressed with the results, so they overstate the jet size needed for a given hp level. And the recommended fuel jets are too rich - at least they do usually tell you this in their tuning instructions. If it were me, I would go down at least three sizes on the fuel jet before trying the 275. You may not need it for 9's. You not need to pull as much timing, but I m not as sure about that.

Rich

 

I would use a 4 jet spread with the nitrous jet being the bigger one. Setting the flowing fuel pressure at 5.5 to start but if your reading the plugs you will have to drop the fuel pressure a little more. I would also pull more timing here is a vid with a .075 nitrous jet and only a total timing of 20*

http://www.youtube.com/watch?v=87beVxhczc8



There is more power in that jet I just start safe on timing read the plugs and add timing tell the mph stops going up. The next pass was over a tenth faster with a 1.5* more timing.

 

jakes what hood is that on ur car?

 

I tried 82N/82F, which is 9 jets leaner and it actually ran worse. It still popped and every few pops it would give a loud bang out the exhaust. I've changed the plate, fuel and nitrous solenoids, ignition coil and alternator.

It runs pretty good on the standard 175 shot NOS jets, and only makes 1 or 2 pops on the top end. I took it to the track on the 18th and ran it on the 175 shot (73N/82F) with a total of 30 degrees timing. It ran consistant 10 teens at 131 with low to mid 1.4 sixty foot and a best of 1.39. The plugs look good. The porcelain is perfectly clean, the timing mark is at the bend on the strap and metal part of the plug is tan in color.

I'm going to swap my Digital 6 for a new 6AL and see if that helps.

Thanks