Fuel Injection

I have been kicking around the idea of converting to a TBI system on my v-6. Anybody have any suggestions?? I didnt see anything in the tech place. The fuel injection with the HEI should be nice.

 

I hate to say this, and please don't take me the wrong way, but - you're opening a can of worms that has been opened several times in the past!!!

I'll give you the basics here, and you can seach for "fuel injection" and get enough to keep you reading for a week!

We have had probably 1500 - 2000 members come through our little corner of the 'net over the past 5 years or so. Of those, only 1 claims to have been successful in going FI on an odd fire. His screen name is "Steverdenver" - IIRC. It's very technical, due to the nature of an odd fire engine pulse. Trust me when I say that every angle and option has been covered (Howell TBI, retro-fit of GM V6 systems, Holly Projection, Grand National systems, you name it).

I'm sure *someone* could do it, but I think it's outside the relm of the average shadetree mechanic.

Disclaimer: If you do the conversion and have success - we want LOTS OF PICS AND A WRITE UP!!!!!!!!!!!!

 

I am running the Holley Pro-jection on my 4.3. I know it's not an odd fire but, it works real well. I don't know that an odd fire would make any diff. with a pro jection setup. If you have the $$$ you might want to get one of the newer systems that you can calibrate with a lap top. I have the older system designed for the V8 but it works fine on my V6. It's a very basic system, that uses a tach signal to fire the injectors, a throttle position sensor, and a coolant temp sensor (basically for the cold start circuit). I bought mine used off of ebay. Let me know if you have any ?? about it.

 

The projection system doesn't care if it's on an even fire or odd fire. The Holley tech support guys will tell you otherwise though.

Adapting a TBI system to a 225 is not really difficult if you're not scared of electronics. I was going to do it to my :v6: but I sold it when I came into a free 4.3. The trick is to use a crank signal in place of the RPM signal going to the PCM. The crank trigger setup made by Holley would do the trick. It's designd for an even fire Buick V6. IIRC, its about $250 from Summit...

One other thing, TBI systems normally electronically control the ignition. TBI grafted onto a 225 wouldn't do this. Not a big deal in my opinion...

If you have any more questions, ask away...

mruta

 

would think you would be time and money ahead to swap out the 225 and get a 231 w/TBI

 

late 80's and early 90's GM full size cars had RWD and TBI.

 

Camaros have 3800 Series II V6s and are RWD. Unfortunately no-one makes an adapter to the jeep trans for these. Other choices are S10s and Astro vans.

 

I'm pretty sure SFI never happened on a non-turbo 231. The NA engine ran an electric carb up through 1987 AFIK.
1978-1983 Carb Turbo
1984-1987 SFI Turbo (intercooled at the end)

TBI's only existed on Chevy V6's AFAIK --Buick was high-tech (but got high failure). TBI's IMO rule due to incredible reliability. On a Junkyard budget, The Chevy's will have more availability.

Now, I personally believe (although never wrenched it to prove it) that a RWD block with 3.8 (pre-3800) FI would work and run the stock FWD serpetine drive.

1984 was the first 3.8 FWD in the 88 and Leslober. The 98 and Park Ave came in 1985. (I may be reversed those cars --I can't remember.) Anyways, it is believed that GM used RWD heads on the FWD for 1984. This may mean that FI intake fits RWD heads and old 225 accessories may bolt right up. I don't remember if the 1984 was SFI or MPI. I'm leaning SFI as that was the "hot" technology of the moment and some parts may have been common with the Grand National (1984 first FI year). The 3800 started in 1988 model year in which many changes were made. 3.8 FI engines ran a little harsh (rough idle) compared to the smooth 3800. WARNING: Pre 1988 electronics (ECM) was a nightmare for reliability.

This would be fun to experiment with if I can scrounge up the parts.

 

I think it might be feasible but it will take lots of figurin and fiddlin. AM

 

3800 out of the camaro or firebird do have the 60* bellhousing plus starter is on the drivers side. Novack makes an adapter for an auto to a 18 or 20. I checked because I've had one in my shop floor for about 3 yrs. I think it would be a good idea with the right transmission. They're relatively cheep and easy to find and make plenty of power.
Might even be cheeper than trying to adapt some other fuel injection to an oddfire.

 

I used the Holley kit sucessfully on my 225. The only gripe I've got is it loads up if you go past 95% throttle while merging onto the freeway and it needs to be re-adjusted when the weather turns cold outside. Works MUCH better than the 2bbl and has A LOT more low end!

 

IIRC GM performance offered a rwd 3.8/3.4 60 degree v-6 crate motor to replace the 2.8 in the s-10. Short block replacement and used the 2.8's intake/TBI.