Orangette

just finished a TBI v6 to Carb 350 swap. 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

-VSS
-CTS
-TPS
-A RPM Signal

Now i did the exact same thing 04SilveradoMykk did in his thread with his Vortec PCM, But my truck was stuck in limp home mode.

Mykk's Thread on GMFS -> http://www.gmfullsize.com/forum/showthread.php?t=145089

I am running a MSD 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.

4. Done!

Picture of wire with a quick disconnect.


Here is a Picture of Holley TPS kit on my Holley 670CFM Street Avenger
DSC01539.jpg?t=1284178889

Picture of whole setup on my orginial 350 with a Demon, engine and setup have changed abit since then
P5240152.jpg?t=1276659075

my Speedo, Coolant temp and all other gauges work like factory (My Oil PSI gauge isn't working cause my Oil Sender is gone, Replaced with an Autometer unit)

So now that your 4L60E is working, lets carry onto Fuel.

Fuel:

I sent up my fuel system a little different then Mykk, 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)
-Assorted fittings to T Gauge into fuel line

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.

P5080144.jpg?t=1276659340

Those are 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, Also T'd into the fuel line and put a 0-15PSI gauge in, shown here.
DSC01539.jpg?t=1284178889

I found that my Demon 650 likes 6.5-7PSI and my Holley 670 like 6 . 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 and isnt worried about emissions or MPG's

-Josh

fun4me

I've seen this thread posted on several different forums & I'm gonna post on all of them so that I can get as much information as I can.
I have a 94 Chevrolet truck. I built a 383 with vortec heads, roller cam, headers w/true duals, super victor intake, & a 454 throttle body. I have a mail order chip & we are on number 20, still has a bad hesitation on accel, rough idle, ect ect ect..... So I decided to go with the FAST EFI system. The problem is that it will not controll my trans & I do not have the funds to spend another $850.00 for the FAST transmission controller. My questions are this.....

1) Can I use the tps signal from the FAST system to trigger my pcm?
2) Can I use the ect sensor from the FAST system to trigger my pcm?
3) If so do I just splice the signal return wires together for these two sensors?
4) Will my factory tach still work?
5) If not what will I have to make the factory tack work properly?

I'm sure more questions will come later, but for now that is all. Any help will be greatly apprecated? I would like to see alot of discussion so that we can all learn from it.

fun4me

Does anybody have any additional information they can share on this?