: Replacing a Northstar with a LS1



denscor
12-03-05, 12:57 AM
I'm new to the northstar life style but I had a thought, Aftering owning three LS1 cars and presently own a 2001 ATI supercharged LS1 Corvette with a number of mod I was thinking why couldn't you put a LS1 in a Cadillac to replace the Northstar motor? The LS1 can make loads of power many LS1 are making power into the 1000 hp!

auroradude
12-03-05, 03:00 AM
im sure its possible with unlimited funds and time.

1998Deville
12-04-05, 11:38 AM
Modern vehicles are so tightly intergrated that changing an engine to one never offered in that vehicle is very time consuming and costly. Cadillacs how so many electronic goodies in the the computer would have to be custom programmed to keep everything working. You'd be better off IMO to find a supercharged N* out of a new V series rather than switching to an LS1. Just my 2 cents.

denscor
12-04-05, 12:21 PM
If you found a donor car it would not make it that hard.Also the LS1 in the Corvette has as many or more electric goodies as the Cadillac. Another question what Transmission is it running? Is it the same one is it the 4LE based one which will bolt to a LS1 or any V 8 base GM motor,which is LS series, 3.8 v-6, 4.3 v-6, Not sure what the bolt pattern on the northstar is. Any information would be great!



:burn:

zonie77
12-04-05, 12:53 PM
Denscor, I'd agree that having a donor car would make it a lot easier. I think it would be possible, maybe not tooooooooooo hard. Getting the cars is the trick. That extra torque would be nice!

There are some old posts about what bellhouseing etc. There was a guy with a N* in a Fiero that put a lot of that info. I think chrfab.com does a lot of sandrail and custom work. Their website has some info.

blb
12-04-05, 01:16 PM
The Northstar is a good bit smaller than an LS1.

zonie77
12-04-05, 01:53 PM
I had'nt thought of the physical length. You only have so much room between the wheels.

eldorado1
12-04-05, 03:10 PM
The northstar uses the same bolt pattern as the 60 degree v6's (2.8, 3.1, 3.4, 3.4dohc, etc etc)

denscor
12-05-05, 12:13 AM
wow that shoots my Idea in the foot about the Ls1 lol! Because its a different bolt pattern1

dkozloski
12-05-05, 12:51 AM
I put a 425HP 396 big block in the back seat of a '66 Corvair. No Guts! No Glory!

denscor
12-05-05, 01:10 AM
cool :jawdrop: I have put a LS1 in a 1997 mustang now it runs better! lol Does the transmission in the Northstars have trouble since thats a 2.8 3.1 3.4 ect based transmission I know that their not designed to handle much power and the north* motor has way more power than that. So are they beefed up?

danbuc
12-05-05, 03:22 AM
Only one bolt on the bell housing is in a different spot. It can be moved provided you can properly cut and weld aluminum. The 700R4 tranny's that CHRfab uses had the bolt hole removed and rewelded into the right place to accept the northstar. I think that the LS1 would probably fit in the engine compartment. It's certainly not as wide as the Northstar is, and I doubt it's that much longer. Of course there the issue with developing new engine mounts for it, and reconfiguring thw wiring harness to work with the stock PCM. You could always run an aftermarket ECU, but then you would most likely loose any chance of getting the dashboard to work properly, if at all.

The 4T80E is not the same transmission as the 4T60E which is used on the 3.8L engine. The 4T80E in stock trim, I think has a maximum torque input rating of about 320-350 lb/ft. It could probably handle more, and of course like any other transmission be built up to handle alot more. It is a very strong, and robust transmssion as far as modern transaxles go. Like many other FWD cars, the weak link isn't so much the tranny, but the hafshafts. Nobody makes aftermarket halfshafts for the 4T80E or any car's that it goes in, so you can really produce more power, than the halfshafts can handle.

dkozloski
12-06-05, 02:40 AM
Do like I did with the Corveight and use narrower tires as kind of a safety valve. Besides the long black streaks and the clouds of white smoke are impressive to the teeny boppers.

davesdeville
12-06-05, 05:10 AM
I'm sure you could take a Caddy, move the radiator foreward, hack out a transmission tunnel, maybe move the firewall back, and stick just about any engine, tranny, and rear axle you damn well want back there.

I'd do a 500ci/4L80e/Ford 9" if I had that kind of cash to spend and time on my hands.

danbuc
12-06-05, 05:47 AM
If I had the money (i.e. win the lottery) I was tinking about a build similar to the one CustomGTP did. It would involve the front engine cradle assembly, and rear axle assembly from a newer F-Body (something with an LS1 for example). Like you said, make a tunnel for the driveshaft, and make enough room for the tranny, and the engine. I'd probably use something like a Tremec T56, basically what's in the CTS-V and such. I definitely think the N* could benefit from a close ratio manual, seeing how much it likes to rev. It would be extremely costly, and time consuming, but it would probably work. Not only that, but I'd have the worlds only RWD 6spd 1998 STS. Reminds me of the Torinado Jay Lenno had built which was converted to RWD with all new chassis and driveline components. CustomGTP's project car has come along very well since he started it. If I recall correctly, I believe he was using some driveline components out of an old Firebird or Trans Am to make that Grand Prix GTP RWD. It can be done, it just take large somes of money, and endless amount of time.

denscor
12-06-05, 07:18 AM
I had seen on LT1 tech were someone had put a LT1 in a Boneville and made it rearwheel drive I don't think the cost was that great. Made it look like a Impala SS! I would still like it to be front wheel drive. Does the Buick Le Sabre use the same frames? If so then I think all Le Sabres have 3.8 which are a V-8 (small block chevy ) bolt patterns! The LS1 has a small block chevy bolt pattern!:thumbsup:

zonie77
12-06-05, 09:53 AM
I just ran across this on another forum.

http://forums.corvetteforum.com/showthread.php?t=1250085&forum_id=48

eldorado1
12-06-05, 11:28 AM
I just ran across this on another forum.

http://forums.corvetteforum.com/showthread.php?t=1250085&forum_id=48


hahaha... I think this thread, and that thread are a case of "the grass is always greener on the other side"... :suspense:

davesdeville
12-06-05, 09:05 PM
Wow, there's a lot of misinformation about Caddys and Northstars even in another GM car forum...

danbuc
12-06-05, 09:11 PM
I know, I was wondering where some of these people were getting this stuff from. Some of the "facts" that they were mentioning were so far off, I alsmost wante dto join the forum just to correct their misinformation. That would be rude though, so I didn't bhother. It's sad to see something like that on a Corvette forum though. You would thnk they would have better knowledge of GM products seeing as how most of them are diehard GM people.

eldorado1
12-06-05, 09:25 PM
Wow, there's a lot of misinformation about Caddys and Northstars even in another GM car forum...

like what? Except for the "operates on 6 cylinders at cruise" part, I didn't see anything else...

danbuc
12-06-05, 11:43 PM
470hp Supercharged N* in the New DTS...

360hp XLR...

I guess it's really just that one guy though.

The 360hp remark I think he got off of CHRFab's website though. That what they have listed as the Factory hp rating for the XLR...