Any thoughts on TBI for 78-83 Turbos...?

[81LimitedT]

Hey, just spitballing ideas out there. I was wondering if anyone had tried a TBI swap for the 4bbl Turbo? I know there are quite a few 4bbl-to-TBI kits on the aftermarket. Anyone here tried to adapt these, or seen them on our cars? Would it even be a possibility to adapt a GM factory system, say from a 4.3L H.O. or a 305 from any of the GM car/truck lines? I'd think that this might be a less expensive option than the aftermarket if it could be made to work. I'm curently working on the cash to rebuild my salvaged 80 MC Turbo setup into my 81 Limited (I've been hoping to do this for almost 10 years now, since college. Just wish I'd known in 92 how rare that rusted out MC Turbo had been before I had parted her out). I also have an 85 3.8 N/A motor to work with too. Based upon some of your advice and reading, I figured 85 block & heads w/ 80 pistons crank, ignition and induction all combined. I have to work with the 4bbl now, but was just wondering if the TBI might be a "half-way" step toward the SFI setup. I might be way off base here, since I have almost no knowledge or experience working w/ EFI. I just know that I'm a very long way from being able to take the jump to the SFI world (not even sure I want to, kinda attatched to my 81 after 14 years and the draw-thru system is just the appropriate thing for this car anyway ). Anyway, sorry to ramble. Thanks for any thoughts!

Mike

 

[b4black]

My wife had a '87 Monte Carlo LS with a 4.3 TBI. I was very impressed with that motor. I thought about the same swap. There is a fair amount involved. It would need all the appropiate wiring, sensors and ECM. It would also need the fuel system changed to a high pressure, electric pump. The stock PROM chips won't work well with the 3.8 or turbo. Somebody well skilled would need to burn a PROM with all the right parameters.

The last step is the key. I believe the TBI/EFI PROM code, unlike the CCC carb code, is well known. If it is, then tuning via the PROM chip would be possible like SFI, and this is were all the benefit from the swap would be.

That's a lot of work, in uncharted waters, with no promise of success. I figure that same amount of work tuning the factory set-up would go much further, with much more likelyhood of success.


PS - It would probaly be easier to put a turbo on a TBI motor, than to put TBI on a turbo motor.

 

[81LimitedT]

Thanks for the reply Rich. I assumed it would be a bear to do, just wondered if someone had any experience. I'm going to go with the original setup. Simpler of course. Another set of questions I had were about the stock cam, and getting the TH350C the car came with to run as a stand-alone from the engine's computer controls. This car is currently a stock '81 3.8 N/A with the original lock-up TH350. I believe there are a few ways available to get this tranny to work w/ lockup without the original control system, but I don't have the specifics. Any help with information about this would be greatly appreciated! I do have all controls and harnesses for the '80 turbo from the Monte, but that had a TH350, non-computer trans.
Also, is there a different cam anyone out there recommends in place of the stocker? This engine had 102K when I pulled it from the MC. I know Kenne Bell has a couple of cam options, and I do have the buildup thec article from the GNTTYPE site, but was wondering what would be advisable as a replacement for this as a street/cruiser car?
Thanks again for any help!
Mike

 

[b4black]

I think it's B&M that makes a TCC control device. Also, try searching the tech pages at www.montecarloss.com Many MCSS owners are convinced they need to remove the ECM, so they have come up with several ways to deal with the TCC.

As for the cam, I would follow Fred Carrado's advice from the gnttype page. I think he likes the Crane 206/206, right Fred???

 

[Freddie's Buick]

Oh yeah....here's the by-pass for the tranny should you decide to get rid of the ECM system. It's a 'standard type' of torque converter power-switch kit. #80217 for all '81-89 THM-350C's, (C- means computer controlled). Goes for about $50.00 and it's made by B & M. On the Summit catalog it's part #BMM-80217. $47.39 and $6.95 for shipping.

Good Luck!!