Convert 79 small block v8 to fuel injection

[bpolitzer]

I purched a 79 GMC pickup with a small block V8.

Unfortunately, the stock carbureter has been replaced with an edlebrock, and it looks like most of the original emissions control equipment is gone. Doesn't look like it will pass smog.

My question - is it possible to convert the engine to fuel injection?

Can I take the intake manifold, throttle body, fuel pump, and computer from a later model 350, and pass smog?

Has anyone had experience with this sort of conversion?

[maxpinck]

I have thought about the same question, while I was googling the topic it came up with a project car, were it was converted from carb to EFI. If I come across that website again, II will give it to you.

[Blue Bowtie]

This is one I did, a '72 Chevelle, passing ther sniffer without a cat converter:

















A TPI from an '86 will fit the older heads. Any EFI from '87-up will fit the older heads if the center bolt holes of the intake base are altered, or you can install later (centerbolt) heads.

[bpolitzer]

Blue Bowtie:

It looks like you did an excellent job, but isn't a 72 smog exempt?

It is in California.

I found an article describing the conversion:

http://www.automedia.com/TBI_Fuel_Injection_Conversion/pht20001001fi/1

I'm still wondering about the smog - this is a 79.

I don't want to go through all the effort if I can't get it smogged.

[MrPbody]

A letter to C.A.R.B. would be in order, to assure it's within the bounds of their rules. Last I recall, even if it WOULD pass the sniffer, it still won't pass because it has non-original parts and emmission control devices are rendered inoperable. The fact that it would be more efficient and pollute less means nothing to bureaucrats. They aren't interested in "right and wrong", all they care about is "compliance"...

'72 models, even when they weren't "exempt" due to age, did not require passing a sniff test at levels of catalyst cars. I left California more than 25 years ago, so I haven't kept up with the local laws like I used to.

Jim

[Blue Bowtie]

In case you're wondering, the complete TPI setup was from ebaY for about $350, including the harness, electric fan, relay panel, and ECM. The owner provided the TPI setup, new radiator, new water pump, and fuel pump, and the rest of the parts are outlined here:



I worked on it intermittently as it sat in my garage for 18 days. I billed it out at 33 hours labor, not including my reprogramming time after it had been running for several weeks to debug and tweak some parameters. If you do it yourself and shop wisely, you should be able to complete the job for right around $1,500, not counting your labor. Over $350 of the cost was in a replacement MAF, replacing some other parts not related to the TPI, a failed EGR temperature switch from the donor intake, and injector service. If you get a good MAF and other sensors (or use a speed/density TPI), decent injectors, and don't encounter other problems, you might save those expenses. This 350 is running on 19 pound injectors (from a 305) so they had to be flowing properly to be able to set up the pressure and constant to be able to map out the fuel correctly.

FWIW, it isn't super fast, but is much more fuel efficient, has loads of torque on the low end, in is consistent enough to have won it's class bracket for the entire 2007 season at Byron. Not too shabby for a 4200 pound slug.

[Blue Bowtie]

Originally Posted by bpolitzer

Blue Bowtie:

It looks like you did an excellent job, but isn't a 72 smog exempt?

It is in California.

I found an article describing the conversion:

http://www.automedia.com/TBI_Fuel_Injection_Conversion/pht20001001fi/1

I'm still wondering about the smog - this is a 79.

I don't want to go through all the effort if I can't get it smogged.

Oddly enough, this was a CARB car. It was originally a California Emissions model from 1972, complete with EVAP. It can never pass a visual inspection in those states anal retentive/stupid enough (of which, there are many) requiring a visual inspection based upon the original configuration. However, it passes ANY state's emissions requirement on a treadmill, so in effect, it is way too clean to be a 1972 vehicle. It still has the EVAP (which is actually managed BETTER by the ECM than by the original vacuum / TVS configuration), and it runs on an active O², just like it should. For a 1979 model year vehicle, if you simply connect a pair of high flow 3-way catalytic converters and no respirator tube (or a single cat for single exhaust), and if you have any clue about programming, it will pass any 1979 model tailpipe emission standard in any state.

Mr. Fiero is absolutely correct. If Californica chooses to be arrogant/ignorant enough to require vehicles to emit MORE pollution because they are older, that explains a lot about what is happening in Sacramento (yeah, I've been there twice, and see what goes on).

On that topic, I seem to recall a recent federal court ruling (just this past week) regarding that, effectively whacking CARB and the rogue environmental rules of the Peoples' Republik of Kalifornica off at the knees, just as it should be.

Check with your state and local regulations first. Where I live, there is no emission check required. One county away, however, bi-annual tests are required to allow issuance of license plates. It's not always a state-wide regulation. Since this vehicle has to be tested, it had to pass. I can probably get a CO, N²O, HC printout from the owner, but I recall him saying the numbers were very low, and actually impressed the tester. I tuned it by lambda, so I knew it was going to be good, despite what the instruments at the state test lanes might say. Evidently, their's were calibrated properly.

[JohnnyL]

I do not know if I have the issue(s) anymore but Classic Trucks magazine ran an article two or three years ago on bolting an 80's TPI unit onto a small block in an early 70's C-10 truck like Blue Bowtie did. The author mentioned you can send the ECM module to GM to get it re-programmed for just about any bore, head, and crank combo.

[Blue Bowtie]

There's no need to send the ECM. All you need is a blank PROM and converted MEMCAL (or adaptor like Moates) and you can burn programs all day long: