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Old 10-17-2020, 02:17 PM   #6
IROCZman15
10 Second Club / Meet Coordinator
 
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Join Date: Dec 2004
Location: Roxbury, NJ
Posts: 2,100
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cool, thanks fellas. Yes, a track rental would be ideal. At the Test-N-Tunes I usually can only get 5-6 runs in. Aside from the Saturday June 5 TnT where I got 11 runs in. I experimented with launching rpms that day as well as with using my lockup feature on the converter, and that amount of runs was very helpful. You are right for sure, the more runs I have that are exactly the same, the better data "pool" I can have and then I can go changing things. I could have filled out the whole front notebook page with the amount of drag passes I have done this year ( which is 41 passes ) and listed all the data, but some of the passes during March, June and July had no relevance anymore, because during that time I was changing ignition timing, figuring out tire pressure and some other stuff. So I only put the most recent 2 month's worth of pertinent info onto paper. Unfortunately, it is all I really have to work with at this point.

Yup, converter was spec'd for this exact motor with nitrous. Sent the converter company the cam card, engine spec sheet, and a list of the other mods, weight, purpose of the car. I told him that the car will be getting nitrous in a year and he said, I can build the converter for that setup and it will be pretty good in the meantime. The goal was so I didn't have to remove the transmission and converter, then mail it back to him plus another $200 this winter just so he could reconfigure it for nitrous use. We opted just to have it done once and I understood I was leaving a bit of N/A performance on the table, but it meant that the car (and me) would be used to it after a year and then I could just leave it in the car this winter. It is probably too tight and thus effecting the shifts, so I am kinda wondering if I should revv out 2nd gear maybe to 6,600 and have it drop into 3rd gear somewhere near 5,000 rpms. First gear climbs just too fast (for me) to reliably shift at a dead accurate 6,300 rpms. In first gear it only takes .35 seconds to go from 6,000 rpms to 6,500 rpms. I'll get better at it, but I think revving out 2nd gear a little higher would land me at a better rpm in 3rd gear.

Won't be revving this engine to 7,000 thats for sure, but I think I will keep the rev limiter at 6,700 or so. Engine builder said to put my shift light at 6,100 and shift it between 6200-6300 with a 6500 rev limiter. He said that would be safe, but also understood I could go a little higher depending on my converter, trans, car weight, rear gear etc.

I had experimented with locking up the converter too during June, and that just caused the shifts to drop much lower into the next gear and the car was a dog. I have the ability to manually lock up the converter in 2nd, 3rd, and in 4th if needed, and this pulls the rpms down a few hundred rpm. It is a toggle switch (actually my old fog light switch on the dashboard) so its not near my shifter or steering wheel. If (on nitrous) I were to run out of rpm at the top of 3rd gear, my thought was to reach over and hit the lockup switch to gain a few more rpm out of 3rd gear, but since I am currently only crossing the finish line around 5,700 rpm I am not worries about that now.
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Last edited by IROCZman15; 10-17-2020 at 02:17 PM.
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