So i bought a TPI set up from manifold up (manifold, runners, plenum, rails, injectors etc etc) from an 88 Vette. I'd like to swap it onto the TBI in the 91 right now(going into a 91 formula w/a 355 tbi 5-spd). i've read all the swap threads already, my questions unanswered are:

Do i have to run speed density on this 91?
will there be any interference with the VATS?
Vette intake bolts up to 91 TBI heads? (i believe it does)

Just bought an ECM off ebay out of a 90 Camaro 5.0L TPI 5-speed ECM# 1227730...

Currently do not have a harness...

Havent played with TPI much, this is an odd ball match since its a Vette TPI.... i couldnt pass up the system for 70 bucks, any help is appreciated.

 

Depends on your car honestly, you planning on running a TPI harness or
using what is in the car? Im not master swapper by any means, but the
'88 TPI system is setup for a 9th injector and is MAF system, and youd
have to run the correct harness and ECM/memcal.

There is alot going on there, honestly id just run the TBI until you can
build a motor to take advantage of TPI or another EFI intake of your
choice. You might see a decent increase in power over TBI but.. at
what expense?

Either way, Im definitely not your guy for this info!

Get a harness, thatll decide MAF or MAP for you I guess. a '90 TPI ECM,
730 supports a *MAP* system, so aim for that no? The vette intake base is different
than the Fbody bases, but still can be used with minimal effort, there have been alot
of topics about that.. search them out! Id shoot for a Fbody TPI intake for cheap.

 

anyone???

 

i was looking for a different intake base so i think that would help the swap, but i thought you need to run an ECM that works in conjunction with the VATS?

i already have the TPI system and the 730 ECM for under 100 bucks, i think i just need a harness... is a 730 ECM a MAF system? i assume if the 730 came out of a 1990 Camaro 5.0 TPI 5-speed, its a speed density?

 

'730 is MAP (speed density )

Nothing 5 mins with a drill won't fix; to elongate the center intake bolt holes to the different angle used on the late cast heads.

The '730 programming has cold startup enrichment so the CSI can be removed and plugged or just left in place to fill the hole

 

Long story short, the TPI system from a Vette shares very few actual parts with the Fbody version. The base is different, so are the runners, same with the fuel rails, and the distributor cover. The computer and harness are different too, even if that doesn't apply to what you're doing.

You don't have to run speed density, but why wouldn't you? The MAF systems on these cars were garbage. The speed density system works a lot better. Forget any myths about cooperating better with modifications, you'll need to tune the computer either way unless it's stock. The 7730 is a speed density computer.

The 7730 computer will look for VATS unless it's disabled in the chip. As long as you still have the VATS module and the rest of the components in your car, it should be fine.

The Vette intake won't bolt up to 87-up heads. The center pair of bolts on each side are at the wrong angle. 87-up Vette heads use the same angle as 86-down V8's. You can probably hog the holes out with a drill, but the EGR passages are different anyway.

Pop the cover off that 7730 you just bought, look up the 4 letter code off the silver sticker on the memcal. Chances are it's out of a 6cyl. It's a typical ebay trick to sell a Cavalier computer as a Fbody. The memcal will probably be the next most expensive part after the harness.

It sounds to me like you've got a mix and match combination of parts. While it's possible to piece the rest of what you need together one piece at a time, it's going to cost you more then if you just got everything from a donor car. You're gonna need to read a bunch of information and understand it before you'll even know what you're looking for. If you decide to go through with it, you'll probably want to pick up a copy of the TPI swappers guide. Personally, I'd sell that Corvette TPI on ebay, assuming that is what it is, and buy a setup that more closely matches your car. Then you can just order the parts you need for your application.

Good luck with it.

 

Correct
All you need is a remote mount MAP sensor seeing as the '88 MAF plenum has no provision for mounting one.

 

Whoops, my mistake sry for mixup, I should have checked! but the intake is usable for
sure, I had an old intake that was drilled for dual purposes and it freaked me out at first!

Least we got some guys chiming in!

Might as well use the ECM you bought, you can indeed plug the
CSI, barely visible but something to consider anyway.

 

thanks for the replies, ill do some research on parts around here, see what i can find and if all goes well ill attempt to install, i have already considered selling it and purchasing a complete speed density set up so that is always an option.... thanks again.