I've seen alot of these threads pop up asking about how to swap a carb and still keep the 4L60E functional.
Here is a how to on how to keep the 4L60E working.
Well, I finished swapping a Carb 350 into my truck, i am using the stock TBI PCM to control the 4L60E. and here is how!
DO NOT ATTEMPT THIS IF YOU HAVE EMISSIONS!
Transmission Control Via TBI PCM:
First off, Here is what the PCM needs to operate the 4L60E
-A RPM Signal
I am running a Stock GM HEI distributor, and it is what i would recommend for a similar swap, I WOULD NOT keep the TBI Distributor, you have no clue as to what the PCM is gonna do without seeing fuel.
Now with a TBI engine, there is no crank sensor telling the PCM if its running.
It took me about a week to figure out what to do, but when i did its easy as 123.
1.Find the plug that used to plug into the Distributor and lead to the PCM.
2.Find the Purple/White wire
3. Take Wire and run it into the TACH position on your HEI Distributor.
Here's the TPS kit I used.
So now that your 4L60E is working, lets carry onto Fuel.
Here is what i used.
-Stock TBI In-tank Pump
-Holley 12-803BP ByPass Regulator (http://www.summitracing.com/parts/HLY-12-803BP/
-Marshall 0-15PSI Gauge, (Not shown)
It is VERY Important that if you are keeping the stock pump, you HAVE to have a return, i dont care what anyone else says, just capping off the return is gonna kill the pump, THE RETURN IS THERE TO COOL THE PUMP!.
Picture of my setup.
I used the stock TBI Fuel Lines, i just bent them a bit and cut off the fittings and installed some new ones.
I then ran a hose barb out the left side to the carb
at first it ran great, but i still wanted to check my PSI, so i added a gauge. using some fittings we had laying around, i dont have any pictures of it, sorry.
I found that my demon likes 6.5-7PSI. and the Holley Regulator is factory set at 5PSI.
After this, the engine ran very well, i would recommend this swap to anyone wanting a bit more out of their engine.
01 Blazer, 4.3, 5 spd, 2dr. Slowly being modded...
93 S-10, 4.3, 4L60E, with a few mods....
Spending money I don't have, on things I don't need, to impress people I don't know...