I have noticed this problem when I push my car to redline between 4th and 5th gear. The first time was at the track day at thunder hill, and again last night at sac raceway. When I shift around 6500rpms into 5th gear and and push down on the accelerator pedal, the car is un-responsive, it begins to slow down, the engine does not rev up until I let up on the accelerator pedal and push back down on it. At the track day, I thought that it was possibly due to low fuel (around a ¼ tank) and the fuel was moving beyond the pickup tube. Last night at sac raceway, I had a full tank of fuel. Someone mentioned something about shift knock which I know nothing about. Does anyone know what may be causing this problem or have any recommendations on how to fix it? I had a buddy at the track day at thunder hill that was experiencing the same problem under the same conditions so I know it has happened to others.

My car is 06 TR, VF39, STi TMIC, MBC, 3” Catted DP full exhaust, EL headers, inlet, intake, and pro tuned. It also has the wallbro fuel pump.

Thanks!!

 

Im not great at these things so its only speculation but a few questions. You may be getting your top mount really hot and by the time you get to 5th your car may be pulling alot of timing.

Again im no pro tuner but that would be my best edumacated guess.

 

My guess is it's knocking and pulling timing. Have it checked out by your tuner of choice.

 

i would talk to the tuner first, see if they have any insight since they probably no you car better than anyone else.

 

I'll call my tuner today, when you guys say pull timing, is there a parameter in my access port that I could monitor to see if this is happening? Does anyone have an idea of what point the timing would render no power? I appreciate your opinions and input!

 

If your using an AP 2 you can log pretty much everything you need and spit it out as a .csv to view on a PC.

If the car is pulling fine in lower gears it's possible as others have said it's pulling timing in your highest load gear, rather than risk damaging your motor conducting runs to log I would suggest as others have contacting your tuner as he will be able to conduct those tests for you with greater margin of safety.

Mike

 

Thanks Mike, it is a V2, but I think I will do what you guys are suggesting and just take it in. I wish I would have logged a couple runs when I was out there last night.