LT1 swap?

[K10 KRAWLER]

I have Been starting a quite of few threads like this in the past bit. I'm just doing research on what to spend all my money on in the winter months.

Long story short, My 1985 trail rig has an old tired engine from a 93 chev truck. I bought the painless fuel injection harness to install it.

The engine is super tired and I need to either rebuild the engine or swap in something better.

My main question is, Should I rebuild my 350 and pile a bunch of performance parts into it or swap in an LT1 from an impala (a buddy is selling one for $1500)

Also, If I were to do the swap, How much would I have to change? Would my wiring harness still work? Will I need to change my flywheel? Does the LT1 have a different belt system?

any info would be appreciated.
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[4X4HIGH]

I have Been starting a quite of few threads like this in the past bit. I'm just doing research on what to spend all my money on in the winter months.​

Long story short, My 1985 trail rig has an old tired engine from a 93 chev truck. I bought the painless fuel injection harness to install it.​

The engine is super tired and I need to either rebuild the engine or swap in something better.​

My main question is, Should I rebuild my 350 and pile a bunch of performance parts into it or swap in an LT1 from an impala (a buddy is selling one for $1500)​

Also, If I were to do the swap, How much would I have to change? Would my wiring harness still work? Will I need to change my flywheel? Does the LT1 have a different belt system?​

any info would be appreciated.​

Wiring harness, computer, accessories are all different. The LT1 is a MPFI engine that uses a MAF sensor and also has an opti spark distributor that is very troublesome (the distributor sits behind the harmonic balancer bolted to the front of the timing cover). The LT1 engine is also a reverse cooling system and will require some special attention. IMHO it's not worth the trouble and 1500.00 for that engine is WAY over priced unless he's giving you the wiring and ECM as well and even then not really a good deal.

 

[K10 KRAWLER]

Wiring harness, computer, accessories are all different. The LT1 is a MPFI engine that uses a MAF sensor and also has an opti spark distributor that is very troublesome (the distributor sits behind the harmonic balancer bolted to the front of the timing cover). The LT1 engine is also a reverse cooling system and will require some special attention. IMHO it's not worth the trouble and 1500.00 for that engine is WAY over priced unless he's giving you the wiring and ECM as well and even then not really a good deal.

hmm, I do wheel In wet environments as well. Oh and its 1500 for the whole car (an ex-police cruser)

 

[Kjunky5]

If it's from a B body it's got iron heads. Everybody hates on the optispark but it's actually pretty tough and was ahead of it's time. The ECM knows where the cam is every .5 degree. Seal everything up, put locktite on the rotor screws and diaelectric grease in the boots and go 100K.

One very important question. What year is the car?

 

[K10 KRAWLER]

If it's from a B body it's got iron heads. Everybody hates on the optispark but it's actually pretty tough and was ahead of it's time. The ECM knows where the cam is every .5 degree. Seal everything up, put locktite on the rotor screws and diaelectric grease in the boots and go 100K.

One very important question. What year is the car?

Ill need to ask tomorrow, he just mentioned it to me, and now Its bugging me if I should take him up on the offer

 

[Kjunky5]

If it's a 1995+ it's got the vented Opti. Being a cop car it should have the green "long life" hoses. Like 4x4high said 1500 is kinda steep for that engine even if it's the whole car. Maybe not when you factor in the trans and wiring. I'm partial to LT1's since I have one. But for 1500 you could drop a Gen III motor in. Or you could yank the engine, trans, ecm, wiring and part out the rest of the car to recoupe some dough.

One more thing. Just in case. Don't be fooled into a L99 4.3 baby LT1. Make sure the 8th digit on the VIN is "p" which means the 5.7 LT1. Or on the options sticker in the glove box.

 

[DEMON44]

Oh bubba. i can get you one for 1/2 that with the ecm harness and tranny still on it.


if you're interested let me know i can get it.

 

[retroblazer]

I own a 95 Imp. I'd spend the $1500 on a rebuild on your current motor and stroke it. I have a 94 Sub that now has a 383 and it rocks.

 

[K10 KRAWLER]

Ok I was wrong, It is a caprice, and still not sure on the year. I think I'll just rebuild what I have for more power, I spent time and money last winter wiring up the Fuel injection nicely into my rig and would hate to tear it out. plus, replacement parts are a dime a dozen, right?

Thanks for the Offer though, Luke!

 

[sweetk30]

ya watch the caprices lots of 4.3 v8 l99 crap motors.

 

[scouthead]

If it's a cop car (was), then the motor is probably really beat. Lot's of departments had their cars rebuilt instead of replacing them. Then they would have seen another 75/100K miles of HARD use - almost without being shut off... Then the car would have been sold at auction, and either rebuilt again by a private party, or limped along until there was nothing left. It would be hard to find a block from one of those cars that had not already been cut once or twice...

They only put out about 40HP more than the motor you already have, which would be easy to pull off with a new set of heads/intake/cam...
The LT1 might be capable of a few more mpg than the lO5 (i assume that's what you have out of the '93? - 5.7L?)
Then there are a lot of people with older caprices that think they have LT1s, but really have a glorified version of what you already have. Real LT1s should be '94-'96...

I say put the money into what you already have. I want an LT1 also, but they are expensive, and the ones in the cop cars did not make THAT much power...

If it is an older car with TBI, and it has all the green hoses/ unity spotlights/ holes for lightbars - then see if you can steal the injector pod and alternator for your car...