I will putting a tbi 454 from a 90 in my truck. I would like to add vortec heads eventually and further down the road add a blower. What changes to TBI were made between 90 and 96 that could effect the blower? The computers wont interchange will they?


Charlo

 

TBI never cam with vortec heads and the L05 had the same crappy heads all the way from 87 till 95. As for the 454, there were a couple changes. Mostly just the trans from a 3 speed to 4. Without the BCC I can't exactly find any of the 454 definition files or I'd tell you what the differences were between years. Your best bet would be to get a 7747 if you're keeping TBI. You could use the 8746, they are like brothers but the 8746 already has an intake air temp sensor but code was designed for the f-body and caprice (including wagon). I don't know what trans you plan on using but it makes a difference. Example; 95 trucks had either the 4L60e or 4L80e, computer controlled. There is a definition file offered by Tunercat to tune the major tables in the newer ecms. One advantage of using the newer ecms is not only trans controls but also the aldl data speed is much better than the crappy 160 baud from the 7747 and 8746.
Give me more specifics and I can point you into a better direction.

 

Ok its a 454 out of an 1990 auto from a 1 1/2 or 2ton. I didnt get what tranny it was but I think it was prolly a th400 unless they were running the 4l80e that early. Its going into my k5 also with a th400. I can live with the slower ALDL baud rate but wouldnt mind the tranny controls. Does an ECM with tranny controls but no electronic tranny cause problems? I may upgrade to the 4l80e down the road, i would like OD and jet makes a sweet 6speed conversion for it.
My friend has a 98tahoe 350 and it looks like TBI. It is definately not multi port. What did chevy use from 96-99?
Thanks for all the help.

Charlo

 

You don't want to run a PCM (trans control) without an electronic tranny if it can be avoided. From 96 on there was no TBI, it was a single large injector with 8 popit type valves. It made good power but doesn't accept standard injectors .
Use the 7747 if you plan on doing your own chips and going with the power adder. If not, just use the stock ecm that cam from the 90 truck. Like I said, I don't know what chips there were for the 454 but the ecm in 90 was definatly a c3 type computer (similar to 8746 and 7747).

 

Charlo, what year is your truck. It should already have the 747 ecm in it, souldn't it JP?

Steve

 

My k5 is an 85. It is also a high altitide federal vehicle(was). Strait q-jet, no o2 sensros and not a feed back carb.
Thanks though.

Charlo

 

Just try and get everything from that 90. That way you just bolt it in, no big deal. 90 was a different body style but it's a truck so the wiring harness is probably twice as long as it has to be . I did a few things to a 90 454ss pickup, felt real good but that bad boy was drinking gas. The VE tables from the factory are at 100 on most of the 100kpa line! Needs to have the fuel pressure bumped up. It has a performer intake that's it and an open element. So I just had the timing come in a little faster and I removed that PE delay, owner likes it and we haven't even been to the track yet.
Tell me exactly what you're getting and I can provide more information. Asking a super general question like what was the difference between ecms from 90 to 96 would take up a few pages.

 

I dont have any more info on the donor truck. I am getting the complete engine with all accessories and brakets, starter, wiring harness, and "most" of the plastic ducting and other **** attached to the wheel wells/fender wells. Basically everything but the ecm and 02 sensor(s).

Otherwise the engine is completely stock. I have plans for aftermarket heads and later on a blower.

This is a smog swap so I need everything. The engine also sat for a year so I need to read up on some info on how to prep it.
Thanks again


Charlo

 

What computer are you running in your car 8746 or 7747 and is there any thing you have to do to run a 7747 in a camaro

P.S. what is the advantage of running a 7747 in a camaro

 

I dont have any computers yet. I dont know the differences between them either.


Charlo

 

At one time the 747 was the only answer, but that was years ago. For everyday use, I'd suggest the 8746.
However.
I just bought a 91 454 4L8E'd 3/4 ton P-U, and I'm impressed with the PCM in it. really nice drivibility, not having bought it with the expectation of good MPG thou, it's for towing.

I'm thinking of using a similiar pcm to the truck in a SBC just for grins.

 

So did they swap computers? or buy one of those expenisive tranny control devices?

I had planned on installing the th400 I have along with the 454 but may dish out for a 4l80e because I need the OD with my 4.56s. I was gonna install the 400 then upgrade to 4l80e later but the controller is like $600. I figure I might as well do it right the first time.

When did GM start using the 4l80e/4l60e?