Backyard Northstar Repair

[KHE]

Putting a 2006 engine and transmission in a 2002 ar sounds like a disaster in the making. A TON of work to get it installed and then no guarantee that it will work. Even if the computers are changed, it is unlikely the wiring harness is plug and play... Nothing about that project will be plug and play...

Thanks for the warning... However, a TON of wiring and bolting and drilling is doable for me; I installed a 1972 model 472 onto the stock transmission in my 82 Eldorado, adapted the TV cable for shifting, installed all of the HT4100's sensors, made an adaptor plate for the TBI injection, swapped in a bigger throttle body after mounting the stock idle control motor, swapped in the stock guts of the distributor into one from a 368, and ran the stock computer with no check engine light. I also converted it to a cable console floor shifter that sat between Mercury bucket seats that were mounted on the stock 6 way power tracks. It rolled on 16X8 F-body wheels. I installed the touring coupe suspension and 70 Chevelle station wagon rear springs, lowered it and adjusted the air leveler for a slight forward rake.... And I did it under a shade tree with no air tools.... What I can't do, is weld or solve complex electronic incompatibility issues. But if the entire power train (engine, tranny, computers, controllers, etc.) Could be transplanted from, say, a 2006+ DTS in full -without welding anything - and bolted into the 02 car in such a way that the computers thought it was still in the DTS, then the only issue would be the body control computer if there's any requirement for digital communication between them.

What I do NOT want to do, is sink $3,000 into the stock engine rebuilding it and slapping on a turbo, only to get another oil leaker in six or seven months. I hate the smell of it on the crossover pipe and having to add a quart every 500 miles.

If I am going to have to sink money into the engine bay, I want to get a motor that won't bleed on hot exhaust pipes.

Three different repair shops told me that as long as I have a Northstar built prior to 2004, it would only be a temporary fix to pay the $2,000 repair bill to split the block and fix the leak.

Is there now a permanent fix for the leak prone seals? If so, then rebuilding my engine with head studs and installing a 100 horsepower turbo would be my cheapest and easiest option to get the car to the next level. I want this engine to work out and head studs could make that happen IF and only IF I get rid of the oil leak permanently.

When oil leaks onto the exhaust, it is most often from the oil manifold plate that is between the oil pan and the lower crankcase half, not the joint between the upper and lower crankcase halves. The GM Engine sealant is really good stuff - there is NO aftermarket equivalent. When used, the engine will not leak.

Keep us informed on your progress.

[Cadillac Jim]

I had my 1997 ETC for fifteen years, got a Jasper at nine years (June 2006), never had a case-half or oil manifold leak. The original engine seeped some oil at nine years; the pan was damp but nothing on the garage floor. The jasper was dry as a bone when I sold the car in 2013. I would listen to KHE and re-seal the oil pan and oil manifold before I used it and not worry about it.

Putting a turbo on an engine and using 5 psi and more boost requires that you lower the compression ratio, increase the piston cooling, and modify the MAP sensor to show boost to the PCM, which may need to be modified to recognize boost. Also, IAT2 should be added to the mix of numbers for the PCM.

chrfab does complete engines for off-road use as well as parts for any model Northstar. They sell aftermarket ECMs and TCMs, also they sell clutches and manuals for Nortstars (and intake manifolds, and carbuetors, and aftermarket fuel injection systems and parts, and turbocharges, and superchargers, ...). I don't know what you would do for a transverse manual transmission unless you went to a beefed-up Pontiac or Oldsmobile transmission.

If you want off-road power in a Northstar, chrfab has been doing it for 20 years and knows what works and how to do it.

[barczy01]

Jeez behind the bumper wow that is way cool.

[CadVetteStang]

Okay guys, thanks for the help; I will go back to the original plans for the car, which is to build the suspension for racing and leave the motor basically stock. I will stick with the proven engine related performance upgrades – Crossover pipe, Catalectic Converter, Turbo Mufflers, high flow cold air intake, flash or tune the PC, maybe slightly stiffer valve springs, use polyurethane bushings in the dog bone mounts…..

For the cost of doing something creative with the Northstar engine bay, I can build the entire really fast project car, that I was planning before I bought this Eldorado. The other car build would put me back into my home engine element (Caddy 500) and give me a car that would serve triple duty (daily driver, autocross and drag).

If I can just get a good, strong, stock build for this Eldorado and stop the oil leak, it will be fast enough and reliable enough to have fun autocross racing.

Again, thanks for the help.