As I flog my stock `87 GN, boost hits 15psi (according to the factory l.e.d. gauge) just as 1st gear peaks... then immediately after the car goes into second gear, acceleration cuts out a little and then the boost fluctuates between 12psi and 15psi with the car occasionally sputtering in it's effort to gain speed. To the best of my knowledge, this car has only had the cat gutted. (bought it from the original 79 year old owner and it has a lot of miles on her) Any ideas?
Fuel pump/sock are the most likely candidates for this. Every T-R by now SHOULD have a new fuel pump in them. When the original goes bad, it does exactly as you describe.
Before you "get on it" anymore make sure you have a good performance fuel pump in there like a Walbro 307 or 340 and run a hotwire per the tech pages.
Chris Bischof
http://perfauto.tripod.com
Thanks, Chris! I appreciate the reply. Before getting your response, I went ahead and tried something. I plugged the air bleed hole for my wastegate actuator control and this limits the boost to 12psi. (as compared to 15psi with it UNplugged) The bucking/choking condition no longer exists under full throttle now, but is this because the fuel requirements are minimized? Regardless, I will be following your advice for a new pump. Where is the best place to get the one you recommended?
I think PTE is having a sale right now on fuel pumps. I want to say around $90 which is a great deal. They can sell you a hotwire kit or you can make your own for about $12 from the tech pages.
Less boost would require less gas and a lower fuel pressure, so yes, the fuel pump is still the most likely cause of your problem. Because it doesn't show up before the shift (when RPM's are high) It is less likely an electrical problem and more likely a fuel problem.
Chris Bischof
http://perfauto.tripod.com
Thanks, Chris! :D