It's been a while since I've been on this site so I'm a little out of the loop... I have a mid 70's 355 motor that I dropped into my 1993 Chevy truck. The motor put out around 450 hp when it was carburated.

For the swap I hooked up the stock 93 intake (modded the stock intake to adapt to the 70's style heads) which made hooking up everything very easy. All I had to do was bolt all the stock goodies on and then tune the chip ( I did have to oblong the IAC sensor) but other than that it was pretty straight forward.

The intake and puny TBI unit has seriously reduced the HP potential but I've been driving it daily for about 2 years with the expectations of someday installing a larger TBI unit. That day has come.....

I now have a direct bolt on SB chevy Edelbrock intake with a TBI from a 454 bolted to it . My question is what is required to connect the new 454 TBI unit to the stock wiring? Obviously I'm going to have to do some chip tuning also. Does anyone have any tips / diagrams/ suggestions?

 

My 7.4L TBI was from a 1994-1995 truck. The TPS was pretty straight forward. the IAC was not. I posted on this about 3 years ago and was given the proper schematic and explnation. Search for my thread. I suspect the harness color code may be the same.

 

I have yet to convert mine, but I seem to remember colour-to-colour was the way to go... Though it is probably best to compair wiring diagrams first.

Please post your findings.

 

This comes up every couple of month or so:

IAC pins C5 and C6 are reversed on the 454 BBC vs the SBC - so swap those 2 pins if using a 454 TB with the bolt on IAC (two M4.5)
The correct wiring for the 7.4 (BBC) IAC valve is as follows :
ECM Con Color
C3 Pin A Lt blu/blk - Coil A Low
C4 Pin B Lt blu/wht - Coil A High
C5 Pin C - Lt grn/wht - Coil B High
C6 Pin D - Lt grn/blk - Coil B Low

//RF

 

Sorry for the delay.....a blown out knee and surgery has sidelined me for a bit. Thank you for the pinout....I'm looking forward to getting this swapped out and feel the power!