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1/4 time and data log. Help! Chasing sluggish engine.
I'm starting to beat myself up with this car. I just feel like its not running as strong as it should given the mods I have and what everyone else is posting with similar mods. 2005 LS2 MN6 BTR Stage 3, Vararam, OBX headers, exhaust, tune (425whp/381wtq STD). Tonight the best I could muster at the track was a 12.54s @ 116.60. 2.1s - 60' , 8.29s 1/8 @ 90.55 with TC on. This is all on street tires and a DA of 2500'. I'm not looking for the best time but I am looking to chase down if there is something wrong with how the engine is running. It seems to run fine for the most part, just slower than I think it should. I've checked for vacuum leaks, bad fuel, cranking compression test, intake blockage etc. I'm trapping nearly stock speeds with a decent amount of aftermarket parts. What else should I look into? The last thing I can think of is checking the degree of the cam, I shade tree'd it and just lined it dot to dot when I installed it. Or maybe I'm just going crazy/need a driver mod bad. Either way let me know what you think or where I could look.
2020 Corvette of the Year Finalist (track prepared)
2019 C6 of Year Winner (track prepared)
Originally Posted by ltdriser
I'm starting to beat myself up with this car. I just feel like its not running as strong as it should given the mods I have and what everyone else is posting with similar mods. 2005 LS2 MN6 BTR Stage 3, Vararam, OBX headers, exhaust, tune (425whp/381wtq STD). Tonight the best I could muster at the track was a 12.54s @ 116.60. 2.1s - 60' , 8.29s 1/8 @ 90.55 with TC on. This is all on street tires and a DA of 2500'. I'm not looking for the best time but I am looking to chase down if there is something wrong with how the engine is running. It seems to run fine for the most part, just slower than I think it should. I've checked for vacuum leaks, bad fuel, cranking compression test, intake blockage etc. I'm trapping nearly stock speeds with a decent amount of aftermarket parts. What else should I look into? The last thing I can think of is checking the degree of the cam, I shade tree'd it and just lined it dot to dot when I installed it. Or maybe I'm just going crazy/need a driver mod bad. Either way let me know what you think or where I could look.
One word - tires.
Trying to obtain useful data with a modified car at the dragstrip (especially a stick) is pretty much a useless endeavor. Did you not notice how much you were spinning right after launching the car?
Get some decent drag radials (highly recommend Hoosiers) and with a clean launch that car should run in the 11s with no other changes necessary.
As far as street tires go, I just took off my 3 year old Nitto NT05r drag radials. Was slightly spinning at track but still ran 12.2@116 with 1.95 short time. Just put on a set of Kumho ecsta SR91 and on the street they dead hook for me. The Nittos never did. Hoping to get back to test n tune Wednesday night to see if there's any difference. Tires are non run flat and high performance summer tires. Car is stock with borla axle back and Diablo 93 octane tune. Ls3 A6
Toyo R888Rs will work great. Here is a run using a Dragy device the other evening in my '84 w/ tko 600 5 speed and 6.0 w/ LS3 top end, 220/224 cam, 1-7/8 long tubes. At that power level, I think your trap is just fine for the DA. Most of those hero runs on the fast list are done in low to negative DA. I would think normal traps for a stock LS2 would be in the low 110s with a 2500 DA.
1/4 time and data log. Help! Chasing sluggish engine.
