[rfmaster]

Originally Posted by cheepin

Just started wiring up my CJ/buggy.Does anyone have a diagram of what sensor is where on a 1988 7.4L bigblock?I think I know what is what but not sure.Thanks.

Welcome to the thread and happy new year.

Regarding BBC EFI wiring - it is nearly identical to SBC wiring commonly found on light and heavy duty trucks (use 1227747 as a guide). The two things to look for are:

1) IAC is different and unique to BBC application. It has been reported by some that two wires in one pair have to be swapped - I have not had a chance to verify this. I'll get to this once I get going on my 383 TBI project.

2) Some HD BBC applications did not use KS. Consequently timing tables are very conservative. This can be easily fixed by reprogramming EPROM to suit your engine needs. HD BBC applications used 1228747 ECM with various BCC EPROM's although there are others (7747, etc) can be found out there.

3) BBC TB is prized by some for its large bore size (2" vs 1-11/16) and higher flow injectors. Note that late model injectors (94+) operated at 30 PSI vs. 13 PSI for 87-93.

//RF