I know, its crazy and it is for a friend. He has thousands of dollars into his 89 tpi that melted when his barn next to the garage burnt. Car didnt actually burn, just go so hot that it totaled the body (rear).
So he went out and bought Sergei Fedorovs old 92 convert to replace it. Now he want his TPI set up to move into the 92. Will it work or is it an electrical communication nightmare. Any thoughts would be greatly appreciated.

 

The 92 probably runs better

 

500+ hp

 

Not sure Im buying it

Why in Gods name would he want to make his car slower and butcher it?

 

..Sell off theTPI and be done..

 

I dont blame you for the skepticism. I havent seen all that is there, yet.
He is a friend Ive gotten to know at my local Tractor Supply store. He has told me it is a 383 stoker, all steel and forged, full roller, aftermarket runners, intake, throttle body and injectors. Has been threw 3 built 700r4s til the current build seems to be holding up. I believe he has in the range of 8-10k just in the engine. he is an older guy working as a manager at TSC. He seems to be a straight shooter. I can understand why he doesnt want to give up his TPI build. SO the question still stands. Can it be done???????????

 

He buys a harness that only uses three wires to hook up the entire engine. You just unplug the existing wires from the original car/engine and run a new 12V constant, 12V keyed, and Ground- to his TPI computer. The new harness runs from the TPI computer then runs to all the sensors on his $10,000 engine.

Call these guys they helped me do a TPI transplant into a Jeep.

http://www.hotrodlane.cc/

http://www.hotrodlane.cc/harnessinst...ssinstruc.html


He would just have to provide Street and Performance with the specifics from his engine and transmission as well all applicable sensors. Good Luck

PS: Have your friend do some reading on their web pages and he will learn a lot.


.

 

The 90 had a tpi and cockpit dash so the wiring loom and ecm from a 90 should work in the 93 but am just guessing, but every year has small changes there may be some head aches involved.

The 91 had a tpi without a maf and used a map sensor, that could technically be used

The 92 had the opti spark distributor driven from the camshaft under the waterpump, i suspect major rewire ecm works unless an opti could be fitted to a tpi but i suspect the block is different. Also the transmission went to 406LE more electronic interface near that year perhaps 94 onwards so check the wiring to the trans.

So in short 90 for ecm and wiring loom may be the only option to keep it slightly simpler using the 89 maf and engine.

 

Nothing will work right on the dash.

 

Anything can be done.
Engine control is no problem (swap in '89 ECM and engine wiring harness) ;interfacing with the CCM
in the '92 that controls most car functions is a different scenario

 

No way to make the 92 "think" the TPI is really an LT motor?....IOW adapter for timing...and whatever else for temp/oil sensors? Are the injector drivers different?

 

Spend $$ and upgrade to a LSX PCM
http://www.eficonnection.com/eficonnection/24x.aspx

Strangely I was recently reading a link from Corvette Fever in '09 about a firm that had developed a complete bolt on system including a reg dist that generated the correct signal so a LT1 PCM could be used on a TPI engine ; was being promoted as the bees knees because you could to flash tuning
Gotta find the link

Gauge /tacho wiring is independent of PCM/ECM
Oil temp input to 92 PCM is for "change oil" function only ; not part of it's operation
Speedo will need sorting as VSS signal on 92 goes to PCM 1st , then outputs to dash instead of other way around on 89
If you really wanted to do it properly you would get the ECM and wiring from a 90/91 TPI car that had the CCM ,the same dash ,and run the engine as SD ; not MAF

 

Man the 94-97 pcm's in my opinion were the black sheep years and were the WORST to work with tuning wise. the older units could be setup for real time tuning with some moates products. I think moving to the flash PCM is a mistake unless it is the later 97 and older Vette pcm which use HPtuners, these flash very quickly and are a lot more reliable... no flash fails leaving you needing a new PCM.

as mentioned before, the 90-91 cars had the late model dash so doing some research into that may be where I would start looking. 92 was a speed density setup so the tach/opti difference is going to be the only real main difference in engine control. any sbc can be setup with sensors like IAC, IAT, ECT, knock sensor, TPS, MAP, Oil Temp, Oil Pressure, and 02 sensors. you could reuse the sensors from the stock LT motor and transfer them over.

to this day I still can't believe nobody has made a opti signal plug that acts like a distributor and can be installed in regular sbc manifolds like a distributor. then you could just use that and convert over to the ltcc setup running 8 individual coils and be done with the distributor altogether.

definitely can be done and probably more then a few ways to skin this cat, just a matter of choosing a direction that will be based on what is most important, money, ease of change, addition of benefits etc...

I wish I was better at electrical engineering and circuitry, if someone could make an adapter for the c4 dash cluster it sure would be easy to switch over to a stand alone engine management system.

Chris

 

It would be possible with some research. The 1992 computer could still control the dash functions and the 1989 computer could be used to run the engine as one option.

Another option

I would speculate that the 1992 computer could be used to run everything if wired corrrectly. It may take some studying of wiring harnesses and a custom prom (to run the 1989 engine in SD mode) but I do not see why that would not work. Both cars are batch fire and the only issue I see is getting a reference signal from the 1989 distributer to the 1992 computer. Take a look at the 1991 SD car, it may have everything your friend needs a newer dash with a TPI engine.

It could be a fun project.

 

It can be done. Whats the problem?

Call Painless Wiring and describe what you have and they will build the harness that you NEED to adapt all this. IIRC you will have to seperate the PCM and ECM so the TPI has its own mngt computer, then the rest of the body can have its own.
Its just a new harness.

There ARE systems that also add a OBD-II computer to older TPI cars to give them multi-port sequencial injection instead of "bank-fire" like all L98s. If THAT can be done, the inverted version is possible.
Its only a matter of money and brains.

 

Found the link I mentioned above
http://www.corvettefever.com/techart...g/viewall.html

I suspect that modified dist would supply the correct "Opti" signal required by the 92/93 ECM as well;
given you can fit a '94+ vented Opti to a earlier LT1

 

i would think that if you outfitted the engine with 89 and 92 sensors, the later dash would work. The tach might not though, and neither would the mileage readout.
Then use the 89 harness and ECM to control the engine. Just use the trans and the engine out of the 89, Just hide the 89 ECM somewhere.
In effect, the 92 PCM would drive the dash and interface with the CCM, BCM, and the 89 ECM would run the engine.
In 89, the trans was stand alone, but in 92, the trans was controlled by the PCM.
So what's the big deal?
2 ecm"s, and some creative afterthought after the swap is done.
Smog police might be a problem though, but I wouldn't offer any information to them.
You might have to use the dual 92 cats and the exhaust from a 92 with the LT1 exhaust gaskets. They will bolt up to the aftermarket heads if they are D ports. Or whatever cats the 89 had.
IMHO, I would put the 89 in the 92, add harness and sensors, and try it.
He can always say that the aftermarket tach is more trustworthy than the factory tach.
OR, try to run the factory tach off the 89 dist. with some sort of buffer circuit.
OR, talk to MSD, and see if they have a multiple spark box like a AL7A that will take the input from the TPI dist. and output a signal for the LT1 tach.
BUt that's what I'd do.
I mean they even make a box to run a LS engine ignition system for a carburetor. I'm sure they can fix your little stumbling block.
And after it's all done, I'd make adapters to run dual calipers on the front discs from a C5.
Just to show how easy the engine swap was.

 

'94 with the flash memory PCM was 1st year for a 4L60E in a C4
92/93 had a ECM with a removable memcal like the TPI cars

The dash / tacho is not driven from the ECM/PCM so that is not a issue

 

I was just pointing out that the expensive trans could stay behind the TPI,
The tach runs off of the optispark, so it may not work.
Don't know much about the later cars, but the basics are the same.
And he will probably have to use two engine computers.
one to run the engine, and one to interface with the car.
I would still contact MSD though.

 

Tacho signal is direct from the coil Neg terminal to the tacho as in previous years
ECM gets it's engine rev indication from the Opti