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TPI Conversion query....what HAVE I done?

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Old Jan 10, 2010 | 02:24 PM
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Default TPI Conversion query....what HAVE I done?

Well, I seem to get myself into alllllll sorts of situations, and I wanted to run this by the forum and get your take on it.

I got a 1976 project Vette a few months ago, and have been working on it a little at a time. I've done quite a bit of sanding, body work, and the likes...and haven't really focused too much on the mechanical side of things. The engine that's in it is a 350 that comes up as a 74-80 block. From the way that the alternator sits on the right side and the brackets that it has on it, my guess is that it came out of a regular passenger car or truck. I can't read the numbers on the back of the block on the passenger side, so it's a guess. I've recently had starter solenoid issues so I have yet to even find out how she runs. To be honest, I was planning on pulling it out and freshening it up anyways, as long as there were no major issues. That was.....until yesterday morning!

I'm such a Craigslist freak........ I stumbled upon a guy selling the motor and all wiring, computer, etc, out of a 1991 Trans Am GTA. It's the TPI 350 engine, and it has 11K miles on it. The kid blew up his transmission and so it has sat for about 4 months up on blocks. I went out and looked at it last night, and she's all there...albeit a little on the dirty side. The donor car is a roach! It's a redneck white-trash mobile at it's finest....but I'm not buying the car, just the engine. A deal was struck for $250..and for that, I get to pick up the car, take it home, take out the engine and all parts needed to make it run, and then take the shell BACK to the kid. Not too shabby, if I do say so myself.

So now I will be pulling the old motor and swapping this one in, in it's place. I've seen a few threads where guys have done this conversion, and I'm curious if it's fairly simplistic in nature? Seems like there IS a lot more electronics involved (obviously) but the benefits appear to outweight the headaches of putting it in. I've seen some wiring harness companies that sell the "plug-and-play" harnesses, and that sounds like the easiest thing to do. Painless wiring is OUT, with a $1200 harness! COUGH!! Can anyone suggest a...dare I say...cheap harness that will work in this setup? I'm just looking for the most bare-bones way to get that engine to run....and run well.

I'm open to thoughts, suggestions, comments, thumbs-ups....and the thumbs-downs. Any insight here is appreciated and welcomed. Did I get a good deal? Or did I miss the boat by using a GTA engine?

Trevor
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Old Jan 10, 2010 | 02:38 PM
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Painless is pretty painfull when it comes to price. Jims performance can help you
http://jimsperformance.com/
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Old Jan 10, 2010 | 04:13 PM
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If you have any sort of electrical experience I wouldn't bother getting a harness.

Just pick up one of the many available guides on TPI conversion and modify the stock harness yourself.

Don't be afraid of it.. the TPI is actually pretty damn simple as far as Fuel Injection goes and is actually easy to wire up especially with a good guide. There are a lot of emissions-related things that can easily be removed to simplify the process.
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Old Jan 10, 2010 | 04:34 PM
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Originally Posted by volition
If you have any sort of electrical experience I wouldn't bother getting a harness.

Just pick up one of the many available guides on TPI conversion and modify the stock harness yourself.

Don't be afraid of it.. the TPI is actually pretty damn simple as far as Fuel Injection goes and is actually easy to wire up especially with a good guide. There are a lot of emissions-related things that can easily be removed to simplify the process.
Do you have any suggestions on the guide that would be the best? I've seen one out there, "TPI swapper's guide", and maybe that's the one you are thinking of. I believe I can do the harness modification myself, I'm just note sure of what stuff I HAVE to leave on there. I certainly want to rid the motor of all of the emissions garbage on there, since we don't have emissions where I live. I also don't know if I would have to have the ECM reprogrammed when all of that stuff is taken off.

I'm sort of going back on one of the things that I truly loved about the 76....no major electrical items, and no computers. But from what everyone says, the TPI conversion will result in a smooth, reliable running motor. This will sort of be my trial run, and then I will most likely put a TPI setup on my 80, which has a 383 stroker in it.
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Old Jan 10, 2010 | 09:06 PM
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You will have to have the chip reprogrammed to remove the emissions, or the computer will start throwing trouble codes(check engine light will come on)

I picked up a TPI unit recently to install on my 383, and plan on using the harness and computer from F.A.S.T. That's for another thread but in the meantime here's the link to the system I will be running in case you might be interested in other options

http://www.compperformancegroupstore...Category_Code=
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Old Jan 10, 2010 | 09:16 PM
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I'll find the exact publication. The TPI Swappers Guide is kind of junk and has only standard GM troubleshooting procedures that don't help much with a swap.

http://chevythunder.com/

This guy has some fantastic info for free Including the ECU pinouts. Should be just about everything you need.
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Old Jan 10, 2010 | 10:04 PM
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Originally Posted by 682XLR8
You will have to have the chip reprogrammed to remove the emissions, or the computer will start throwing trouble codes(check engine light will come on)

I picked up a TPI unit recently to install on my 383, and plan on using the harness and computer from F.A.S.T. That's for another thread but in the meantime here's the link to the system I will be running in case you might be interested in other options

http://www.compperformancegroupstore...Category_Code=
How exactly are the chips reprogrammed? What is the cost, where do I do that, and is there a source for doing that that you would suggest?
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Old Jan 10, 2010 | 11:14 PM
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Default Well, since you axx'd.....

Here's the website where I gathered most of the info for the little bit of learning that I've done in reprogramming your same generation ECM.

91 V-8 should be a 1227730 ECM. Lots of experience from these folks repogramming those chips....

Take a look....lots of helpful folks there.


http://www.thirdgen.org/techboard/diy-prom/

ps-by the way, get the harness and all the fuel connections and leads running to and from the ECM...it'll make your life easier later.

Last edited by carriljc; Jan 10, 2010 at 11:18 PM.
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Old Jan 11, 2010 | 07:04 AM
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Jagsthatrun.com has a TPI Engine Swapping book. It thoroughly covers all of the questions you asked and then some.
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Old Jan 11, 2010 | 10:06 AM
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I bought my '72 in '95, so there have been several installs of a TPI/LT1 setup on it over the years, computer is NOW behind the map pocket, where it belongs, fits nice up top/center hung by two straps to the cowling, the computer location determins the wiring...well duhhhhh....

chips@pcmforless.com
E-mail Address(es):
chips@pcmforless.com

is the guy who did my cal pak, Alvin Anderson? been a while...it works fine... go to his web site and see....charged me 150 bux....but it's been a while too....

you want to eliminate the VATS, EGR, etc...not a issue, just plug the passages....

the engine is the almost same identical thing I have in my car now, a roller 350-355, I would pull the heads and have them sealed and redone/inspected by your local GOOD head shop....

replace the water pump, and keep the serp drive, I assume it will fit the vette, if not you need drives from a '88-91 vette, which is what I have....the comprsser will need new hoses, but with 134 you need use barrier hose anyway...keep ALL fittings and get your local a/c or hydraulic shop to make them up for you, keeps things simple...

you CAN use your present accessories, but I wouldn't....

otherwise it's a bolt in swap.....

IMO, if you take your interior off, pull the ducts without disturbing the large wall mounted pieces, you will find a dip/space between the ducting inside, when you go through the firewall, it's behind the dizzy and in the clear enough, making it a ideal spot for your wiring to pass through, this keeps your 1227730 computer as above...totally dry....

one thing you will need, is to look on ebay, and find a good WELLER soldering station, many variations on the theme, pay no more than 80 bux, and get some tips from some supply house, 800f is the temp you want....this will allow you to properly solder and then tape your harness neatly and then cover with that standard GM/everyone plastic wrap tubing, makes it nice and neat, make sure you string the wires out nice and relaxed and similar slack to each location....

I would be very surprised you didn't have enough wiring in the stock harness to do the job....

if you have any questions, feel free to PM or email....

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Old Jan 11, 2010 | 10:20 AM
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Originally Posted by mydejavooo
How exactly are the chips reprogrammed? What is the cost, where do I do that, and is there a source for doing that that you would suggest?

The chip needs to be worked by someone with the right software & knows what they're doing.
The link from the above poster looks like a good place to start for the info you're looking for. May ask the C4 guys who does their programming also.
My only dealing with the GM computer was with Fuel Injection Specialties out of San Antonio back when I installed TPI on my 84 GMC. Had to run a stock chip because of emissions

Sorry I couldn't have been more help
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Old Jan 11, 2010 | 01:21 PM
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Am I understanding this correctly? You are buying the engine out of a 'beater' race-mobile in which the owner blew-up the transmission...and you intend to just pull the engine and put it in your car without opening it up and checking its condition?
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Old Jan 11, 2010 | 02:06 PM
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Jim's Performance....I sent my wiring harness & computer to him.....told him what to remove & what to keep/add.....wiring harness came back marked & easily installed; computerr came back reprogrammed....& Jim is just a phone call away to answer any questions while you're putting everything together. 1.877.465.9569
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Old Jan 11, 2010 | 02:59 PM
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Originally Posted by 7T1vette
Am I understanding this correctly? You are buying the engine out of a 'beater' race-mobile in which the owner blew-up the transmission...and you intend to just pull the engine and put it in your car without opening it up and checking its condition?
I can understand where you are coming from, and I guess additional clarification is warranted. The CAR is a beater, no doubt about it, but the engine is not. The motor is a rebuilt engine with paperwork, that was dropped in the car, and the transmission blew out. The kid that owns it tried to rebuild the 700r4 transmission, and he didn't do it right. So the engine is the best thing on the whole car. But....as I pointed out, I'm not taking the whole car, just the engine and wiring stuff. In looking at the engine, it's clearly a crate motor...and in far better condition than the rest of the car. If it didn't have the paperwork to back it up, I probably would still buy the engine just for the TPI setup and everything that's included. $250 bucks for all of that is still a good deal. I'm not scared off by the condition of the car itself...even though it IS ugly. I call it a "roach" just because those cars are kind of icky, in my opinion. And there are a lot of them out there in that condition. But again, that's not indicative of the engine condition. Shoot, I've seen some of those "icky" looking cars just flat MOVE!!
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Old Jan 11, 2010 | 03:03 PM
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Originally Posted by autoist
Jim's Performance....I sent my wiring harness & computer to him.....told him what to remove & what to keep/add.....wiring harness came back marked & easily installed; computerr came back reprogrammed....& Jim is just a phone call away to answer any questions while you're putting everything together. 1.877.465.9569
Wha did he charge you to do all of that? I'm currently communicating with Tracy at Fuel Injection Specialties, getting an idea for the cost of a stand-alone wiring harness with a performance Stage 1 chip. So far it looks like $395 for the harness, and $195 for the chip with VATS bypass. Not toooo bad, considering that it's a plug-and-play setup. I'm still gathering all of the information that I can, so that I can make an informed decision as to which route I will go. I'm just looking for the least amount of muss and fuss....just bolt up the engine, plug in the wires, and tune her up.
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Old Jan 11, 2010 | 04:05 PM
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I'm hooking up an '86 TPI to an '88 200-4R transmission...so, here's a breakdown:

wiring harness & computer rework....$100
Chip....$189
Vehicle Speed Sensor...$75.00
Plus my shipping to him & his shipping back to me.
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Old Jan 11, 2010 | 06:19 PM
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Originally Posted by autoist
I'm hooking up an '86 TPI to an '88 200-4R transmission...so, here's a breakdown:

wiring harness & computer rework....$100
Chip....$189
Vehicle Speed Sensor...$75.00
Plus my shipping to him & his shipping back to me.
Mystery to me how anyone can do a wiring harness when they don't know the exact location of the computer when placed in the car, final mounting, plus some extra for service work....

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Old Jan 11, 2010 | 06:52 PM
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Lots of things he & I discussed that I didn't put in that post...one was computer location, another was extras I'm adding like dual electric fans, another was wiring configuration & routing....several phone calls back & forth....everything plugged right in to engine & trans & there's enough wire for me to install my computer.....best thing to do is call him & ask questions.
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Old Jan 11, 2010 | 07:00 PM
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Originally Posted by autoist
Lots of things he & I discussed that I didn't put in that post...one was computer location, another was extras I'm adding like dual electric fans, another was wiring configuration & routing....several phone calls back & forth....everything plugged right in to engine & trans & there's enough wire for me to install my computer.....best thing to do is call him & ask questions.
Sounds like he is less expensive than having a new harness made. How long was the turnaround time for everything? And did you have to do anything else when you got it, or did you just plug it in, fire it up, and go? That's pretty much what I'm looking for, although I am realistic in the sense that I know I will have to do some stuff.

Oh, and what did you do for a fuel pump? I found some in the $125-$150 range that will work...one that is mounted to the frame rail.
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Old Jan 11, 2010 | 07:32 PM
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I modified my '77 fuel pump by adding the '86 pump:

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