wiring harness from monte carlo?

[thaubol]

I currently have the 305 out of a monte carlo sitting on an engine stand, being cleaned and readied to be put into my truck. Because I will also be using the auto window switches, ac, cruise control, and a few other things, i was considering using the wiring harness out of the car as well.
i will be installing a t5 behind the engine, and i was wondering if anyone knew how this would effect the ecm, or if there are any other major changes that im going to have to make. I realize this may not be super easy, and many people will say not worth it, but im a kid working through college and i have a lot more time/brain power than money at the moment...
if anyone has any knowledge, experience, or advice for this it would be a great help to me.

[Tinkermc]

What year Monte are you asking about?

[rcbildr]

www.thirdgen.org has a couple forums that might have the information you need for the ecm. Is the Monte 305 cara'd or injected? If it is carb'd, you can get rid of the ecm completely by buying an older hei and non computer controlled carburetor. I did that to the 305 in my Z28, the PO replaced the distributor with a non computer one and in order to make the car run well I found an edelbrock (non computer) q-jet, rebuilt it and have been driving it daily. It was a good thing I removed the ecm too, the leaks from the t-tops were causing some strange corrosion on the case of the ecm. If your set on keeping the ecm, I would think an ecm from a carbureted (assuming your monte 305 is carb'd) 305 camaro with a 5spd would work.

[thaubol]

Thanks.
So I was thinking really to keep the ecm in the interest of trying to realize a bit better fuel economy. Your idea of finding a ecm out of a carbd camaro 5 spd I think would work, but my monte is an 88 and is still carbd, while I think camaros were fuel injected at that point? I'm gunna have to do a little research into that though, I might be wrong and/or be able to find somthing to make this work.
If not, have you ever heard of getting the existing chip reburned, or getting a new chip burned for the existing comp?
Posted via Mobile Device

[MARKDTN]

I have used harnesses from other cars in street rods and similar. It is a touch and go kind of process. You will have to do a lot of rewiring. The column will plug in and headlight switch but that is about it. Ignition, wiper, heater switches are different. It can be done, not sure it is worth it. I would fix the truck harness you have, I think you will be better off.

I would junk the ECM control on the 305 and find a Q-jet from an early 350 or 307. I think you will have more difficulty keeping that computer than going with a non-computer carb. The mileage gains will be minimal.

Now if you want mileage and power out of that motor, buy a Tuned Port setup and put on that 305. Now you have something worth playing with a computer. The 305 in a carbed '88 SS Monte is the same roller cam longblock motor as an IROC Camaro and works really well with TPI added. You can probably buy a TPI setup with computer and all for a few hundred if you shop around. I have put TPI on a '72 and there are others who have done it.

[thaubol]

hmm thats actually a really good idea. i like the way tpis look too so thats a very real possibility for me - would definitely be something new to me, but then again ha most of this build is going to be new territory.
Ive found a tpi for an 88 camaro for 200 shipped, which i thought to be a pretty decent price, but havent been able to find the ecm specified for a t5. i will continue searching.
as far as the wiring harness, i have been toying with the idea of the monte carlo harness vs. a painless harness or something similiar from another company. obviously, with buying new, there is the advantage of asking for everything you need and the lack of headaches on the install. i was really only considering the wiring from the monte in the interest of saving money, but also because i thought that with the dual headlights, and with me trying to use the auto windows, locks, cruise, ac, etc. from the car that it would be pretty close to the same.
on that note though, i wonder if that money wouldnt be spent anyway in reprogramming the computer for use with the t5....

[Kidd-7]

I have no experience with the 305, but have seen new chips or reburning chips for other vehicles go into the hundreds. New may be the way to go...

[rcbildr]

Originally Posted by thaubol

Thanks.
So I was thinking really to keep the ecm in the interest of trying to realize a bit better fuel economy. Your idea of finding a ecm out of a carbd camaro 5 spd I think would work, but my monte is an 88 and is still carbd, while I think camaros were fuel injected at that point? I'm gunna have to do a little research into that though, I might be wrong and/or be able to find somthing to make this work.
If not, have you ever heard of getting the existing chip reburned, or getting a new chip burned for the existing comp?
Posted via Mobile Device

I think by 88 the base model V8 camaro had an option for a carb'd 305. IIRC there are guys on the thirdgen site that can either burn you a chip or suggest one to use. I think I stumbled across the ecm out of my camaro (83 Z28, 5spd, carb'd 305) you can have it if you want...I'll double check tomorrow and let you know.

[MARKDTN]

Originally Posted by thaubol

hmm thats actually a really good idea. i like the way tpis look too so thats a very real possibility for me - would definitely be something new to me, but then again ha most of this build is going to be new territory.
Ive found a tpi for an 88 camaro for 200 shipped, which i thought to be a pretty decent price, but havent been able to find the ecm specified for a t5. i will continue searching.
as far as the wiring harness, i have been toying with the idea of the monte carlo harness vs. a painless harness or something similiar from another company. obviously, with buying new, there is the advantage of asking for everything you need and the lack of headaches on the install. i was really only considering the wiring from the monte in the interest of saving money, but also because i thought that with the dual headlights, and with me trying to use the auto windows, locks, cruise, ac, etc. from the car that it would be pretty close to the same.
on that note though, i wonder if that money wouldnt be spent anyway in reprogramming the computer for use with the t5....

The ECM itself is the same for a stick vs: auto on a TPI car. The difference is in the PROM. It is easy to find a stick PROM or have an auto one reflashed. The only wiring is for the converter lockup, but I think you will get a SES message if you don't plug it in. If you can find a whole unit with an ECM and wiring for $200 I would say that is a good deal. The '88 is a Bosch injector that does not have as many issues as the later Multec injectors. You may be able to use them without cleaning or replacing. All you need them is a fuel pump (use '88 Ford truck external) or on my conversion I used a TBI S10 Blazer tank out back and swapped to an IROC pump.

I am not a big fan of Painless harness. They are OK for a street rod, but I would much rather fix a stock harness. If you do, throw away the crimp connectors and go buy some type 56 connectors and solder them in as needed. When you are done, buy some good harness tape and make it look nice.

[thaubol]

kidd-7, my brother got a chip burned for his fox body mustang (house divided, haha) and it cost him upwards of 300 if im not mistaken. i was thinking about that along this entire thread, but figure if i get it burned by the right company in order to realize a little more bottom end power and fuel economy, it might be worth it in the long run, even if only for 1 or 2 mpg gain. since ill be using this truck every day and to travel between home and college (220 miles) i dont think it would take too long to get the money back in savings.

rcbildr, wow that would be awesome man thanks....im pretty sure that one way or another that would come in pretty handy. if you end up finding it let me know for sure and we can work something out.

markdtn, i found an entire tpi setup that im very interested in, going to try to get it for around 700. has a stand alone computer with a simple 2 wire setup...the only thing i was worried about then is how it would tie into the car computer. regardless, if i can get that to work, ill just be disassembling the harness from the monte (1. to see what i have and what i dont need, and 2. to check for and coating damage from insects or mice) and runnin that through the truck. plus, when we went through the harness for my bros mustang we bought a huge kit of shrink tubing and wire ends and there is tons left over so i should be able to revamp my harness where necessary.

[MARKDTN]

$700 is high for a used TPI setup unless it has lots of new parts or really good injectors-stay away from "good" used Multec injectors. I would expect $200-250 for a used TPI unit, $30 for a used 7730 ECM, $100 reflash a V8 PROM or $200 for a flashed PROM, $100 for a new VSS generator, and $450 for a new good Howell harness (or build your own cheap-see below). You can go with Speed Density on your stock 305 bottom end that you have instead of Mass Air Flow and that will save mounting a MAF sensor and wiring for it (also don't use the 9th injector). The Howell harness is an easy 4 wire setup-hot, ground, ignition, and fuel pump. If I did another one in a 67-72 truck, I would use a Corvette style 7727 PCM in the engine compartment, also used the same 7727 PCM on some of the 3.1 cars. The PROM is the same for both. This would allow you not to eat up glovebox or underdash space with the ECM. If you can find that 7727 PCM in a car(Lumina, Grand Prix, Cutlass Supreme), you can adapt that wiring harness by adding 2 injector leads and extending the knock sensor lead. I have a 3.1 Cavalier harness for my next TPI swap.