so i just bought a 87 TII S4 with J-Scpec engine and it runs really lean according to the apexi Turbo Timer and was wondering what that could be?..What is good compression?.i tested it and its at 90 on both rotors..?.when should i get a rebuild done..every how many miles?...and the tach and all other gauges dont work except speedo? what do you think? and mods that i should do?..its got a full 2 1/2'' HKS exhaust, downpipe, and an aftermarket catback. should i get three so its not as restrictive?..and im getting a apexi safc...

Trevor

 

How does the TT check AFRs? wtf.

 

it has a few things that it keeps track of...but it says 14.5 for afr and thats lean..even maz-tech here in boise sayed it was running lean..