Cantletgo

I have an 85 GSL-SE that I have owned for 10 years (my 6th 1st Gen going back 30 years). It has 163K on it and had been running fine. It is garaged and maintained regularly. recently i noticed it has begun to bog down when trying to rev it higher than 4K RPM's and am at a loss as to what it could be. It has been tuned recently and does not miss or seem to have a fuel restriction when kept under 4K RPM's and runs just fine when I don't race it a little-which defeats the purpose of owning it. It is pretty much stock other than a mind train cat-back exhaust put on it some time ago. I also should add that I plan to take out the catalytic converter and put in headers. I have been told this problem may be an exhaust restriction as well and I don't know enough about it to speculate if the catalytic converter may be causing the issue but I will be taking it out anyway. Any suggestions are appreciated.

-Ted

Cameron38

iTrader: (2)

Could be your 5th and 6th ports are not opening up. They are supposed to open up at 3800 rpm I believe. This would affect your upper end performance. A loss of 20+ HP above 3800 rpm. But this problem is so subtle most people don't even know they have the problem. If you're feeling a almost complete loss of power at 4k, does sound like something else.

Cantletgo

Thanks, I have been told it is probably a fuel or exhaust issue. I am going to have it looked at by someone who will know what to look for.

7aull

iTrader: (2)

when was the last time you replaced the fuel filter...? should be yearly.
This has caught me a couple of times, now I just automatically drop a new one in every spring...

Stu Aull
80GS
Alaska

t_g_farrell

iTrader: (1)

Yep sounds like a fuel issue. Too many folks want to think its a cat issue. Cats do get clogged
sometimes but when they do they usually have symptoms like excessive heat at the cat and
it will be glowing red at night.