LS9 rotating assembly in an LS3?

[GTAHVIT]

OK, I've done a little checking and based on my research... which isn't a whole lot... it looks like the Crank, Rods and pistons from the LS9 would be a direct replacement for the LS3...

OK. So we all know the LS3 heads flow pretty well. Is it recommended to go with the LS9 internals on a stock LS3 block????

IF so, would it be worth it???

is there a better aftermarket option out there? Am I even making any sense at all???

Tuners, sponsors and members please share your thoughts on this.

I'm thinking I might learn a few things from this discussion.

[SSE 4 2SS]

Have you looked into buying a shortblock. There are some companies out there that are making a really good product very reasonably priced...

I'm not really biased, but I do know that you can get a forged balanced blue printed LS-3 sleeved block from ERL for less than 4 grand...

There are some options for head studs etc... Those are all a personal choice... You know the power I'm putting down and other than cooking a turbo for what ever reason, I've had no issues so far... Time will tell on that of course... though they say that a motor with big power will fail pretty quickly if there is a fault.... and yes, I've pushed mine really hard already, though it is on a very conservative and safe tune...

As for the LS-3 heads, I know they have the capability to flow at least 390 CFM... Ask me how I know...


Just asking...

[GTAHVIT]

I'm really just thinking out loud here.

At some point a while from now, I'd like a bullet proof ( as much as that is possible and affordable ) 700RWHP build.

I'm just wondering about the feasability of using the LS9 internals or if anyone would even consider it?

[paul2010]

For the price you could probably build better cheaper. Also the LS9 heads are much better. From what I understand LS9 ported heads you can run more timing and get much better flow then LS3 ported heads.

[full of days]

GMPP catalogue has the race top end with flowed & ported head which would work fine on a stock LS3 bottom end. I'm building a NA motor & not going with a blower or turbo However as 700 hp causes lots of things to break & is not good for the bank account as you will always be fixing broken parts...

[Irnwkrkev]

LS9 rotating assembly = BIG $,$$$. Titanium rods, forged crank, forged pistons, new flywheel for crank, etc. You can build a strong enough motor just by swapping to aftermarket forged rods and pistons... of course while you're at it a stroker crank is a cheap upgrade when rebuilding the shortblock. The factory crank will handle 700+ hp all day long though.

[GTAHVIT]

Originally Posted by Irnwkrkev

LS9 rotating assembly = BIG $,$$$. Titanium rods, forged crank, forged pistons, new flywheel for crank, etc. You can build a strong enough motor just by swapping to aftermarket forged rods and pistons... of course while you're at it a stroker crank is a cheap upgrade when rebuilding the shortblock. The factory crank will handle 700+ hp all day long though.

I hadn't thought about the flywheel... I did like the idea of Titanium rods... but I guess that might be overkill for what I'm thinking... I was pretty sure the stock LS3 crank would hold up but wasn't sure. So... maybe LS9 heads????

Again, I'm thinking there are just as good or better aftermarket heads for less money???

[mlee]

Does PQ know about your latest premonition...:emoticon7:

[GTAHVIT]

Originally Posted by mlee

Does PQ know about your latest premonition...:emoticon7:

OH dude, this is so far down the road... He's got nothing to worry about...

[Slowhawk]

A forged shortblock from a sponsor will be cheaper and stronger. Titanium rods are not the strongest out there.

[Hess Motorsports]

Hey guys..... I hate to burst your bubble but converting to LS9 isn't that simple or cheap. yes the parts are similar for cubic inch but that is where it all ends. Don't foget the LS9 has a 1.5" longer crankshaft snout to drive the two oil pumps for the partial dry sump AND for the larger 6/11 rib drive belts. Whcih means you will have to buy all LS9 timing components, front cover, water pump, accesories, A/C system, power steering components, a dry sump pan, AND build a custom oil reservior.

The job is a complete nightmare (we just finished a complete LS9 conversion including blower) and the misc parts required to complete it properly put the job cost well over the point where it would be worth it to 99% of customers.

For the money, use the new Darton sleeves (stronger than LSx block AND, you can keep the weight down and better cooling), port your heads, run a ZR1 cam, stroke it out to 434CID and toss forced induction on it. There is an easy 1000hp recipe that makes sense

[Caliman93230]

Originally Posted by Hess Motorsports

Hey guys..... I hate to burst your bubble but converting to LS9 isn't that simple or cheap. yes the parts are similar for cubic inch but that is where it all ends. Don't foget the LS9 has a 1.5" longer crankshaft snout to drive the two oil pumps for the partial dry sump AND for the larger 6/11 rib drive belts. Whcih means you will have to buy all LS9 timing components, front cover, water pump, accesories, A/C system, power steering components, a dry sump pan, AND build a custom oil reservior.

The job is a complete nightmare (we just finished a complete LS9 conversion including blower) and the misc parts required to complete it properly put the job cost well over the point where it would be worth it to 99% of customers.

For the money, use the new Darton sleeves (stronger than LSx block AND, you can keep the weight down and better cooling), port your heads, run a ZR1 cam, stroke it out to 434CID and toss forced induction on it. There is an easy 1000hp recipe that makes sense

What would a 418 forged cost labor included, thinking about doing this soon

[GTAHVIT]

Originally Posted by Hess Motorsports

Hey guys..... I hate to burst your bubble but converting to LS9 isn't that simple or cheap. yes the parts are similar for cubic inch but that is where it all ends. Don't foget the LS9 has a 1.5" longer crankshaft snout to drive the two oil pumps for the partial dry sump AND for the larger 6/11 rib drive belts. Whcih means you will have to buy all LS9 timing components, front cover, water pump, accesories, A/C system, power steering components, a dry sump pan, AND build a custom oil reservior.

The job is a complete nightmare (we just finished a complete LS9 conversion including blower) and the misc parts required to complete it properly put the job cost well over the point where it would be worth it to 99% of customers.

For the money, use the new Darton sleeves (stronger than LSx block AND, you can keep the weight down and better cooling), port your heads, run a ZR1 cam, stroke it out to 434CID and toss forced induction on it. There is an easy 1000hp recipe that makes sense

Just for a point of discussion..

Like we've mentioned above,

What about on the stock LS3 crank??? does it make sense to go with LS9 rods and pistons?

[Caliman93230]

i would like to know what parts are essential for a forged ls3 and what stock parts I can keep,