2002 WS6 LS6 Swap

[tav8ws6]

Hi everyone,

I have a 2002 WS6 with an M6. I came across a 2005 LS6 motor I may swap into my car. It comes with the LS6 ECU. What to I need to do/look out for when completing this swap?

Assuming I keep the motor stock, all I would need is to put a stock cable throttle body on the motor and relocate the accessories. Should I use the LS1 or LS6 ECU?

If I put new valvetrain (for higher rpms) and headers on the motor and install, I know I'll need a tune, but would it require anything else?

Thanks!

[pajeff02]

I am not sure what year they changed from a 24x to a 58x reluctor on the crank or if an '05 still has a 78mm throttle body which would make a difference in airflow... The engine itself will be a bolt in affair. Was the donor car also M6?

[tav8ws6]

Fortunately all first Gen CTSVs were M6s. I read the 2005 LS6 has the LS2 timing chain, but otherwise I believe there were no other changes. I can easily measure the throttle body. And the reluctor I believe was changed only in the LS2, but I can research that as well.

[SMWS6TA]

Check the crank sensor. Black is 24x, gray is 58x. If 58x you will need to use the ecm it came with or get a 58x to 24x convertor. To be honest it's cheaper to pull the crank and have a 24x reluctor wheel pressed on. IIRC the convertor is around $400.

If it is a 58x and you need to use the LS6 ecm the biggest problem is the wire harness. You'll need to make sure the dash gauges connect to the same wires for the ecm. You may have to repin it to work with your cluster.

Also the stock rockers perform very well with a Comp cams trunion upgrade. It's what I'm currently using with my 403ci.

[tav8ws6]

Cool, thanks for the info. I'm actually playing with the idea of getting it to rev at 7000rpm. Just for fun. I don't want to change the cam or heads. And I don't care about the powerband. I just want it to reliably rev up to 7000. Seems like springs are the only necessity. The trunions you mentioned seem smart too. Possibly new retainers?

Also I'll probably put kooks long tubes & high flow cats on with a nice throttle body. I'd avoid using a larger one or a larger intake manifold if I could as well. I'd throw a lighter, but not too light, flywheel on it. And a lighter crankshaft pulley but only if its stock diameter, if that even exists.

Fun motor, nice power, quick revving.

[SMWS6TA]

Stock cam will not go to 7k. You will kill the motor, ask why I'm a 403 now instead of a LS1.....

Stock cam going that high you're looking a floating the valves and a bunch of other stuff that will kill it.

Getting the stock throttle body ported & polish will be your best bet if sticking with the LS1/6 intake. Don't bother with a 85mm. With it being P&P you'll get the same gains and performance.


Now if you want a bump in hp and still keep it a nice daily drivers look for a 228 cam. It goes well with stock heads and mild bolt on's like LT headers.

[tav8ws6]

Stock LS6 is limited to 6600rpm. Think I'll have issued with another 400?

[SMWS6TA]

Yes...

[tav8ws6]

Didn't know the tolerance was so low. Maybe I'll just leave that stuff alone

[SMWS6TA]

Most stock V8 cams are set about 6500rpms. My cam is up to 7000.

[Firebirdjones]

A stock LS6 doesn't make power up that far anyway so if you aren't interested in changing the cam and valve train designed to make power upstairs, then trying to spin it to 7,000 isn't going to do much for you. I don't think I'd want to push the stock bottom end that far on a regular basis either.

My Z06 was bone stock, and just the way it was I found it to be a fun little engine. One of my favorites from the LS lineup. Smooth power up to 6500. In the light weight Z06 it felt strong. Too bad they don't offer the engine in crate form anymore.