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Old 06-08-2020, 03:09 PM   #98
IROCZman15
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Join Date: Dec 2004
Location: Roxbury, NJ
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I took the car over to Island Dragway this past Saturday for Test and Tune. My goal was to perhaps crack into the 11 second zone. I now have Mickey Thompson ET Street SS drag radials on the rear iroc wheels, and was going to revv out the engine more in each gear. I am no experienced drag racer, and the car is not a competition drag car, but seeing an 11 second time slip (naturally aspirated) would be killer. I got "close" but I am not quite there yet.













I took very un-exciting in car videos (mostly for my own use to hear the engine and shift points), and I data-logged each pass. Prior to heading to the track, my tuner and I have really nailed down the low rpm and mid-range rpm stuff. Driveability and low end pulls are just awesome. We only had a chance to do two tune revisions with WOT data. Also, those two WOT data sessions were on the street with hills, traffic, and only included 1st gear and 2nd gear pulls to 6,000 rpm. I was really hoping for a more dialed-in tune revision for WOT fueling before the track day, but we didn't have time to get that done. However, now, after the 11 1/4mile passes of data, we can certainly use that data to dial in the fuel table up top. I am still learning EFI tuning basics, so I am hesitant to do any adjustments myself.

The weather was good, but a bit hot. Only about 30 cars came to the Test and Tune day, and a majority of them had packed up and left by 1pm. I got 11 passes in that day, I was going to stop at 8, but I changed my mind once I started getting into the low 12.2 zone and decided to make a few more laps. I tried using the Torque-converter lockup switch on a few runs, and saw no gain, in fact on one run it slowed me down. I have read of others locking the converter at higher rpms, because it will pull the rpms down and you can avoid shifting into the next gear if you are about to cross the finish. One run I locked the converter at the top of 2nd gear, and this caused the rpms to drop too low when it shifted into 3rd. So, no more doing that.

I was hopeful that my new re-calibrated tachometer from Cajun Tach supply would have arrived on Friday, but it was actually delivered Saturday while I was at Island dragway. So, While racing, I had to do my best to guess what RPm I was shifting at since my oem tach is significantly off. I set the rev limiter on the sniper efi to 6,600 rpm and hit the limiter a bunch of times....the tach was showing right at 7,000 rpm when the limiter activated. I'l be installing the new tack (and 80 psi oil pressure gauge) soon. Should I adjust my 6,600 rev limiter? I might think about adding a small shift light since I don't want to watch the tach needle while going down the strip. However, cosmetically, i DO NOT WANT a huge in-your-face shift light. something simple and subdued is more my style.


anyways, time slips are here:





- I hot lapped it the last 3 passes! if you look at the time on the last 3 slips, 3 passes in 9 minutes!




videos:
1 https://www.youtube.com/watch?v=ryAffM0lLJc 12.56
2 https://www.youtube.com/watch?v=x2-eVJPUDs0 12.33
3 https://www.youtube.com/watch?v=qUPiK_8jxbk&t=1s 12.55
4 https://www.youtube.com/watch?v=g6cz3LK4aCc 12.33
5 https://www.youtube.com/watch?v=uNqHD9zuNKs 12.66
6 https://www.youtube.com/watch?v=pirMZqVFBfA 12.35
7 https://www.youtube.com/watch?v=sHnE43p2_XI&t=3s 12.21
8 no video 12.26
9 https://www.youtube.com/watch?v=v0KxB35IkmQ 12.20 *best of the day
10 https://www.youtube.com/watch?v=R5E8RUVCp98 12.41
11 https://www.youtube.com/watch?v=25j4KzzUK2Q 12.50
in the lanes next to turbo camaro https://www.youtube.com/watch?v=lEg4Ud8tpUQ


and I know I can't post tune files or datalogs to this forum, but I can screenshot them or take photos of them. If anyone has the knowledge and wants to chime-in let me know your thoughts.



Quick observations:
-Off the bat, from my limited EFI knowledge, I am pretty certain I need more fuel at higher rpms. The CL comp limits we set were for -20% to 20% and learn % was -5 to 5%. So the CL COMP (yellow line) looks like it was adding fuel to the base table up to its limit (of 20%) and then it couldn't add anymore (because we pre-programmed not to) so it just held it at 20% fuel added and robbed me from horsepower. right???

-3rd gear (a 1:1 ration in a 700r4 right?) is not exciting. I am through 1st and 2nd gear and shift into 3rd by the 1/8th mile. I am trapping 92 ish mph in the 8th mile, but only picking up 18-19 mph to the finish? finishing consistently between 110-112 mph. Less than ideal. It has a 3.55 gear ratio and I know that is unfriendly, but remember this is a pure street driven car. Also a 3,400 edge racing converter. anything I can do to make the top end of the track more aggressive?

-I gotta figure out if my exhaust is a restriction. my MAP goes down during all of my runs, and I was running with No air filter and the sniper efi feeding into the edelbrock victor jr intake which should be great for high rpms, so it shouldn't be an intake restriction ? my 1 3/4" mid length dyno dons headers shouldn't be it, the dyno dons y pipe? hooker 3" cat back.. but I have a 3" exhaust cutout that I keep open and its mounted along the main pipe before the exhaust bends up over the axle. thoughts?

-the MT ET streets are great. I didnt feel tire spin off hte launch at all. during passes 8,9, and 10 I was getting 1.73 second 60foot times. I am not revving up the engine much on the starting line. maybe to 1500-1700 rpm before the car wants to creep forward. probably could be better. I did remove the front sway bar, too. without installing a trans brake, anything I can do to get a harder launch?














Overall, another good day getting used to the car. I street drove it there, and street drove it home. It rained around 3pm right after I made my 11th pass so I decided that was my sign to pack up and head home. Picked up two orders of chicken wings at marleys in Hackettstown (mango habanero and Kamakazi) and drove home. Unloaded the tools, swapped the wheels, and washed the car while chatting to neighbors. The next day I participated in the Cops-N-Rodders fundraiser cruise/parade event that started in Roxbury and Ended in Hackettstown at Piggys BBQ. The car drove great the whole trip, even is heavy stop-and-go traffic and it only got up to about 193 on the temp gauge. Again, street car duties are important. I saw Larry at the cruise too, and Chris was there for part of it. Took some video, but I there was no aggressive driving on my behalf, so the videos are just cruising.

https://www.youtube.com/watch?v=8DrfA9c0p1E

https://www.youtube.com/watch?v=Y1MxiLS2G3s

https://www.youtube.com/watch?v=pJsRzuchssw





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Last edited by IROCZman15; 06-08-2020 at 08:15 PM.
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