I have a late 70's 454 Im putting in a 72 K20 and I was wantin to EFI it..I planned on going to ther junkyard getting a EFI system with intake..Would this work or am I going to have to switch heads? or alot of problems?

heads are fine. It should be a bolt on swap.

What type of EFI are you looking for?

The 454 TBI's used just an adapter on top of a quadrajet style intake.

If you use a 1996 – 2000 L29 Vortec 454 MPI intake you will need to change heads for sure. With TBI you are safe with the old heads as Lil’John stated. 1988 – 1991 TBI 454’s only used the qjet adapters. 1992 – 1995 had a TBI specific intake.

So pretty much the 88-91 TBI will bolt to my Edlebrock Performer intake? Have ya heard any ups and downs on the 1988-1991 TBI's?

X2 on the Q-jet manifold. My 88 'burb had TBI, should bolt right on.
Grab as many sensors off donor as possible..

So pretty much the 88-91 TBI will bolt to my Edlebrock Performer intake? Have ya heard any ups and downs on the 1988-1991 TBI's?


Yes, with the Qjet to the throttle body adapter that was on the 88-91 engines. They pop on ebay once and a while. You can also buy an adapter from Howell EFI and a few other places. The TBI 220 models on all the V8’s are pretty good units. I have not heard any year of TBI is better than another. There is something about 1995 that is different but I think it is more with the ECM than the TBI unit. If you use a 1995 system you might want to research that.

ok thanks alot man! I'll prob start looking for a 88-91 TBI..U think its worth putting EFI on this 454 for gas and power diff's? Does the TBI have to be off a big block or will a small block work?

The tbi has to be off a big block. Just so happens I have a big block tbi for sale. You would still need a computer and harness plus sensors though.

What u asking for it? Besides the motor harness what other sensors and wires am I gonna need?

The 5.0L and 5.7L TBI's will not work... they are too small.

You need the 454 TBI... it is what is commonly known as a 2" bore TBI. I see them "all the time" on ebay going for around $150 to $200.

The stock adapter also pops onto ebay going for $50-$75. Aftermarket ones pop up for about the same.

Like the guy above me, I've got one for sale also... but a complete setup minus the oil pressure sensor and dizzy. Mine is setup for TH400(ie has kickdown relay that is ECM controlled)

What Im doing is building 72 K20 with 454 newer model 5spd and wanting to EFI it with maybe a bigger cam..its going to be my pulling truck..any ideas?

The TBI will accept a little bit of a cam... a slightly bigger one with a reprogram. You get too big of a cam and TBI will just not work.

I was looking at something similar except using a 472 Cady with TBI on top of it:eek: Project was abandoned:( So I have no idea how the TBI would have worked.

Here is a picture of the TBI unit and stock adapter I used:
http://www.pirate4x4.com/forum/attachment.php?attachmentid=279001&stc=1&d=1167075552

I am asking $125 for mine. You would then need all sensors and a computer and wiring harness. I am unsure if you will need a different distributor

Lil john
I have a 472 Cady motor was going with that but put it in a 86 Mercedes Haha.. what sensors do I need? and wiring harness?

botiejeep
Ok thanks I'll c what I can do..what sensors and what all harnesses do I need the motor? and inside for the computer?

It wouldnt matter if it was a AT as long as I had a manual computer right?

Computer can get programmed manual or automatic (7747 is the ECM I have)

My setup is 90% complete: stock harness harness, TBI, adapter, MAP sensor, O2 sensor(I believe), temp sensor, all TBI mounted sensors, TH400 kickdown relay/wiring, etc. What it is missing currently is the distributor and a VSS. I've even got the ALDL plug and wiring:eek:

The factory setup I have didn't have the knock sensor/computer, EGR, or smog pump related stuff. I could track down a distributor for it and would like to get $300 for my setup(new 02 plus a new backup as well as new water temp)

Does it have to be a certain distributor? VSS?

NEWB here but thought I’d post my experience with swapping BB Chevy TBI’s and maybe get a little advice at the same time. I have a 1987 GMC V30, D60/14B, 4.56 gears with lockers front and rear, 6” lift with 40” Swampers. I had lived with a high mileage, fairly underpowered (in comparison to my other BB trucks) stock BB for some time until I broke an exhaust manifold stud. I had a well running 1973 9:1 CR large oval port head spare engine and that finally gave me an excuse to pull the stock engine and throw in the 73. The stock engine had given me years of trouble free service so I wanted to keep the stock FI. I called Summit and ordered an Edelbrock Performer cam which I was assured would work with the stock FI and threw it in to the 73. Everything else from the stock engine found its way on to the new engine. Intake and exhaust manifolds, distributor, knock sensor, egr, etc. However, I could never get the engine to run right. It fired right up first crank but under the slightest load, it would bog and backfire though the throttle body. Idle would vary wildly from 500 to 1500 RPM’s but it would run the truck around the yard.

I checked everything I could think of. Ignition timing was spot on. I spent numerous hours fiddling with the valve adjustment (the only thing that seemed to make a difference). I checked for a vacuum leak. I even pulled the front of the motor off to check the cam timing. It was perfect.

After several days of frustration, I called Edelbrock to get some advice and they said no, the performer cam, even though it was fairly mild, would NOT work with the stock TBI and gave me a contact to a place to reprogram the computer.

I called the reprogramming place and was informed it would cost nearly $800 to fix the computer compatibility issue.

Being this is a beater mud truck, it’s hard for me to justify this cost given the HP limitations of the TBI and that I could get a Holley truck avenger that would fulfill all of my needs and probably give better HP than the stock FI for about half that price.

Am I overlooking something obvious? Flame suit on…

Yep,
quit trouble shoooting and tuning with your wallet and use the resources avail!!

You can get everything you need to tune your TBI chip for about $100.

A carb will never perform off road as well as FI or propane.

If you are a mall crawler then throw a carb and a HEI distr in and call it good.

If the cam was an RV style cam for bottom end/ offroad then the TBI would work fine.
If you went with a mid to top end cam then it takes a lot more tuning on the chip to correct for it. (that means learning how to do it)

But either way you need to use something like winaldl and a cable to log the data from the engine/ECM to know what the system is doing.

you have to get the BLM data and the data logs from the ECM.

I'm going to be running an RV-type cam in this upcoming 454 refresh.... I have not heard, read, or learned anything that makes me think it can't be done. :D :D

TBI is about the easiest decision to make-- costs less than a new carb, at most junkyards anyway, and works so much better on hills that it's not even funny.