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Discussion Starter #1
hey guys out there! I need help. i have recently put a 350 in my truck with a tpi set up. the problem I am having is finding a wiring diagram for a tpi and one for the stock wiring in my truck. the tpi is from a 1987 corvette and my truck is/was a s10 with the 2.5 four-banger in it. if anyone knows where i can find these diagrams online or fairly cheap i will be one step closer to driving this beast. i am getting frustrated with it just sitting in my shop and the thing is begging to be driven..thanks in advance for any help
 

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You will not be able to wire it with your stock wiring.

You have the computer for the TPI correct? You'll either have to cut the old wiring out of the Vette, or get an aftermarket harness from Painless or someone else. I'd go for the aftermarket at its so much easier than retrofitting the old harness in.

You also have the fuel system setup for the TPI?
 

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Discussion Starter #3
i have the complete intake. the complete original harness and have a computer on the way. what I am looking for are the under hood diagrams (wiring) for both vehicles (88 s10 and 87 corvette). I know that there is going to be now way to just wire it up with the stock harness. I will do the wiring myself but cant seem to find the diagrams.
 

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Get a haynes manual. They have the diagrams in the back. Id also get some colored pencils so you can color the lines in the book according to what they are on the harness. Most of the wiring is straight forward as they have specific clips to plug into specific injectors. You'll probably have to trace down power and ground wires and a few misc wires.
 

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Discussion Starter #5
the injectors and all of the connectors are not a problem. integrating the rest of the harness is going to be the issue. thanks for the advice. i will probably just have to buy both books or go to the library and photo-copy them. who knows. i will probably benefit from having the books on hand.
 

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Hey Neeper...I have the wiring diagram for the big plug that comes through the firewall. Send me a pm with your email address and I will send you the file (the board won't accept excel files).

If you don'e have excel, I think your browser may read it so you can print it. My 1991 Sonoma was a 2.5 TBI, so I think it will be about the same as yours. Let me know if I can help. By the way, Siggy is right about the Haynes manual. It has the most complete sets of wiring diagrams I found.

Good luck,

Bluesman
 

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Neeper, I put a TPI system in my 55 and ended up with a new harness. What you are going to have to do is chage it from a MAF system to a MAP system. I was a dumby when it came EFI and still am. Icalled Painless and Ron Francis to ask some ?? before I comitted to doing this, neither one wanted to answer my ? all they wanted was my money.

Call Centech Wiring and ask for Jim Stafford, he took the time and answered all of my ? and then some. I ended up getting all of my wiring from them and am very pleased.

Oh yea, one more thing, your computer, you say you've got one coming ,do you know the number? the one you'll need is a 7730, I think this has been update, just go to a GM dealer and they can give you the new # or ask Centech. If you have anymore ? just get in touch with me. good luck.

It might help if you had a number [610] 754- 0720 or www.centechwire.com
 

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You do not have to convert to a speed density system. If you have all the components for a Mass Airflow (which you should seeing as how its an 87 TPI), just get a harness for the MAF type setup.

Unless you have room constraints in front of the throttle body, or plan one using a supercharger, there is no reason to convert to a MAP system.
 

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OK , my mistake , don't want misled or give bad advice. either way he is still going to need an after market harness, I believe. I had the stock harness and a wiring diagram and still got confused. Reading a diagram is not hard, but for some people it can be over whelming. after markets come with all wires labeled making it much easier, thats all.
 

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Discussion Starter #13
hey thanks for all of the advice. I just spent a good part of the other day doing all of the basic wiring. now I need the diagrams for the details. reading the diagrams is not a problem for me....I work on car audio electronics all day every day. I thought about the aftermarket harnesses for quite some time. My conclusion was that the stock harness I got with the tpi was complete. in complete I mean everything from the computer(less computer) through the firewall to all of the sensors and even the junction leading back through the firewall on the drivers side. all i have to do make my splices at driver side connector from the tpi to the stock harness
 
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