LT1 in a 1967 C-10

[smoky02]

Alright, my dad just bought an LT1, he got the wiring harness from the engine to the firewall, and he got the computer that goes under the dash. I have a few questions, and I also need some advice. Is there another computer that goes with the tranny, or is it also controlled with the engine computer? Who would be the best company to order a harness from? I know painless is supposed to be really good, but I was wondering are there any other companies out there that are just as good, or not as expensive?

Thank you in advance,

SSgt T.

[c10addict]

Just my opnion... STAY AWAY FROM PAINLESS!!! I bought a bad harness from them for my TPI motor.. Their tech support sucks and their return policy sucks.. Call Street and Performance.. They know their stuff and have excellent support...

http://www.hotrodlane.cc/

Good Luck...

[Andy4639]

c10addict,

Just my opnion... STAY AWAY FROM PAINLESS!!! I bought a bad harness from them for my TPI motor.. Their tech support sucks and their return policy sucks.. Call Street and Performance.. They know their stuff and have excellent support...

What he said! Mine came from them too and they have been doing this a lot longer than anyone else.

[shifty]

Try Speartech. If I knew then what I know now, I would have never been a dumbass and tried to skimp and save $$ on my wiring harness.

http://www.speartech.com/

They offer LT1 solutions. CALL THEM.

I could sit here and offer advice till I'm blue in the face, but I'll just say this: After my LS1 swap in my truck and going through the wiring, I think you would need to be a certifiable idiot or mildly insane if you tried to go with another solution out on the market other than Speartech. Everything they put out is plug and play.

Some might come in here and say I'm being harsh...some of the guys here are very talented with doing their own wiring (I admire them), but the reality is - if you don't want to think about it - you just want plug and play - you want something that looks neat and works out of the box with minimal effort - pay the extra few bucks @ Speartech. Oh yeah - buy their stuff and get unlimited support for your swap via phone with friendly guys, from what I understand.

[shifty]

By the way - per their website:

Harness for LT1 with 4L60E or T56 (94-97 style) $650

It's actually pretty inexpensive compared to what I was expecting. They can tell you if you need an add'l controller for the tranny, but I think all of that support is built into the ECU/PCM/whatever you want to call the main computer box.

[slowtruck]

the ECU controls the trans. and the engine, no need to get another controller

[pdr510]

Lt1 wiring converted my harness to a stand alone. http://www.lt1350.com/

[smoky02]

thank all you guys very much...all your inputs are very helpful

[Slammed70]

What year LT1? And what did it come out of?

[faribran]

its a 94 LT1.. out of a caddy

[Slammed70]

Originally Posted by faribran

its a 94 LT1.. out of a caddy

Its not an LT1 then....its the L35 or whatever they called them. Its a cast iron headed 265 version of the LT1. Same one they put in the patrol cars. And being a 94 I would suggest throwing it in the trash. The non-vented Opti is gonna give you more trouble than you probably want to mess with.

[c10addict]

Originally Posted by Slammed70

Its not an LT1 then....its the L35 or whatever they called them. Its a cast iron headed 265 version of the LT1. Same one they put in the patrol cars. And being a 94 I would suggest throwing it in the trash. The non-vented Opti is gonna give you more trouble than you probably want to mess with.

I had a 94 Impala SS that I put a very hard 70K on.... I replaced 1 opti spark.. Other than that I had NO problems... If you choose to take Slammed70's route call me and I will come throw it away for you....

[djnutcase]

Go here to find out for sure: http://www.impalassforum.com/vBulletin/

Everything you ever wanted to know about LT-1 engines and B-Bodies (Caprice, Roadmaster, Fleetwood). I think the 10th digit in the VIN tells you whether it's LT-1 (at least in the Caprices it does).

L99 was the 4.3L, and I thought the Caddy had the actual LT-1 that year too though...the Caprice and Impala SS did. You can replace the Opti with a new GM unit that's vented, it's true that the 94s had issues. You can also replace with a direct coil ignition, which turns the Opti into a triggering device only.

http://www.delteq.com/default.htm

My daily driver is a '95 Caprice 9C1...fun car.

[Hart_Rod]

Make sure you check the back of the block. They make a 4.3 V8 that looks identical to the 5.7 version. Me and a buddy found out the hard way. Also, if you end up getting it, I've got a new water pump and so other LT1 parts left over from my 48. Let me know.

r

[Slammed70]

Originally Posted by djnutcase

I think the 10th digit in the VIN tells you whether it's LT-1

Tenth digit is the year, the 8th is the engine. An LT1 is a P

[slowtruck]

If the block has the #327 cast in the side of it you have a 5.7. Sorry I don't know what the cast in # was were in the 4.3's.

[67_C-30]

They actually have 5.7L or 4.3L casted into the back of the block so they are easy to ID.

[Project1970]

Cadillac definitely got the LT1 in '94 for their biggest boats.

I'll second Speartech. I've fought more than a few wiring gremlins with my LS1 swap (I think I finally killed the last of them over the past two days) and out of all of them, only one was on Speartech's part of the wiring - and that was one simple splice out of way too many on this truck.

If you've got the original harness and it's in reasonable shape, he generally charges less to rework the stock harness than it would cost for an all-new one. It comes back about the same either way - mine was a reworked stock harness that had sustained some damage in the crash that killed the donor car. He'll lengthen what needs to be lengthened, shorten what needs to be shortened, cut out what's not needed at all, and label everything you need to hook up.

[AuggieStyle]

i hate refering to another site but this one helped me a lot with my swap.
http://ls1tech.com/forums/

[N2TRUX]

I have to agree with Shifty. My personal experience with Street & Performance was Mark Cambell will screw you if he gets a chance.

[faribran]

It has 5.7 LG on the rear and "327" on the drivers side below the spark plugs...
looks like a 350 to me

[piecesparts]

For the money AND the support, I recommend "Street and Performance". I have a TPI motor sitting in my garage with a harness from them hanging on it, this motor is going into a later model truck. The harness is well designed and is easy to handle. I am working on a LS-1 motor for my 68 C-10 and they will be my source for the harness and other things.

Mark Campbell is the owner of the S&P shop and is usually in the office at 5 AM and there until 7 PM, daily during the week. Call him early and talk to him about your needs. I think you will be surprised at the service and the investment he gives you.

His place of business is unique and worth a trip to see. Great vacation idea for a gearhead.

[faribran]

Pieces,
thnx for the input..

[Wootdog]

I would also suggest Street and Performance. I have known Mark for over twenty years. His staff is knowledgeable. I have their wiring in my 96 LT1 in a 67 C10.
KERRY

[Wootdog]

They also have a troubleshooting section on their website that has all the connections. In other words the schematics.
Kerry