I have a 65 Pontiac Tempest that I recentley purchased in fairly good condition. I also purchased a Ls1 with a 4L60 trans attached. The motor and trans came out of a 98 Firebird that took a hit on the passenger side. It has 66,000 miles on it. It comes with the computer, all driven accessories, engine wiring harness o2 sensors ect. The plan is to figure out how to first fit this powertrain into the 65 and then get it running. I pretty much have most of the obvious stuff coverd like the driveshaft and fabrication of the trans and engine mountings. The biggest fear I have now is how to get this motor running in the car without the entire cars wiring harness. I have very little experience with working on ls1 motors and am very intimidated by this project. Please let me know your thoughts on potential obstacles I may have to overcome and any pointers in gereral for a guy thats in way over his head!!

PS One freind recomended going carburated to solve many problems but are the kits to change over available for an LS1?

 

Edelbrock makes a nice LS1 kit with a dual plane intake, also includes an ignition box with a programmable timing curve. Literally, the kit was designed to retrofit an LS1 into an older vehicle using a carb. That would probably take care of some of your wiring woes!

Sounds like a great project! I'd get a factory manual for the 1998 Fbody, and see if that helps.

 

Painless wiring makes a harness for the LS1 so you can hook it up in any early model car, it comes with all the sensors and ecm too. That way you can still keep the fuel injection.

 

I spoke with a tech at painless wiring today. He said that that is was nearly impossible to run the motor off of the engine wiring harness alone since it is dependent on the chassis wiring harness, which I do not have. If anyone has got an LS1 to run off the engine wiring harness alone, please let me know the tricks. As far as the Edelbrock carb setup goes will it be compatible with the elec. controled 4l60? What I really need to know is if I should concentrate on getting it going with a carb set up or if it will be better and less riskey to use the existing fuel injection.

 

Buy the wiring harness from painless and go injected. Its not as bad as you think. Take your time and double check everything. Ive done the swap on about 2 cars and since you got the fabrication part done it should be a breeze to finish the rest of the car off. The harness from painless is nice and neat and labled very clearly on where everything connects to. You will need an edit program as well to make sure the car runs perfect because you will be needing to turn off some error codes from when you start the car for the first time.

Hope this helps.

 

I'd get with our sponsor Speartech and figure it out with him.

That new intake just came out and you have so much going on that would only complicate it all.

 

I recommend John at Speartech as well.. one of the greatest parts of the LS1 is the EFI systems and computer control for tuning.. I cant imagine going back to a carb setup

 

We can set up your LS1 engine harness to run perfectly well without the chassis harness, or we can build you a new custom harness to go with your project.

Whatever you decide to do, do not go the carb route! You'll be giving up so much; you'll wonder why people thought the LS1 engine was so great. The complete LS1 fuel injection control system is a big part of what makes this engine what it is.

 

Thanks John, I think that is what I will do. I sure am thankfull that my freind metioned this site to me or otherwise I most likley would have all ready electecuted myself attempting to figure it out with drunk freinds.

My next obstacle is a fuel system in this bad boy. I have really been scratching my head on this one. It seems that there is no possible way to use any part of the stock fuel system. Any recomendations on who to contact?