hey i have a 91 tii and it has apexi dual exhaust and apex intake and i was wondering if it would be ok to put a DP on or should i upgrade the fuel pump and cooling system??thanks

-Neil

 

stock fuel system cannot support more than 10-11psi. What kind of boost are you seeing right now? Probably more than that. Get a walrbo atleast.

 

Do still have the main cat? The S5 wastegate is pretty good and I've heard that say, with a full RB exhaust and intake it'll still hold to 6# or so (no boost control). So you s/b OK.

Not a bad idea to upgrade your fuel system anyway though. Just watch how much boost your pushing. I didn't go over 8# before I upgraded my pump and put in the S-AFC. The S-AFC is basically only for trimming idle/cruise with a little over 10#. Full load air/fuel ratios in the mid 11s. I'm still on a stock exhaust also. I saw an increase in fuel pressure of 2 or 3# at the rail after the Walbro.

 

Make sure you have an FCD if you don't already.