98 MECHAM TA

iTrader: (1)

Can someone help me so that I do not make a $3,000.00 mistake? Here is my problem, I'm building a N/A ls9 stroker motor for my 98 Trans am. I am keeping it wet sump for simplicity, and I am trying to figure out what length snout on the crank I need. It is being custom made at a well known Nascar engine shop. It is free, but if I get it wrong it will cost me to cut another one. There are two different sizes snouts just by 1" in length. My builder said that the racing engines are dry sump and they use the shorter snout, but what I gathered the dry sump production engines use the long snout. So I think I need the short snout sense I am doing wet sump. Which one do I need? Thanks for the help.

Briou

iTrader: (1)

I believe that you need the short snout crank....the long snout is for the dry sump oiling system

98 MECHAM TA

iTrader: (1)

Thats what I think also, but my builder is weary B/C thay use the short snout on their racing engines which are dry sump. The ls9 is just a beefed up ls3 with the piston oil squirters. So can I just go by the size of an ls3 snout sense it is a wet sump motor?

Briou

iTrader: (1)

I would think so, but I have zero experience with a ls9...

98 MECHAM TA

iTrader: (1)

Thanks I'll have him look into the ls3 crank and see what he thinks.

A_VAS

iTrader: (16)

The LS9 crank is a forged piece, and same length snout as the LS7 (both are longer snouts for the factory 'hybrid' dry sump oil pump drive)

If you are going to do a wet sump, you can use the short snout just like an LS3/2/1 crank would have.

why do you call this a LS9 build, just curious? are you using the LS9 block ?

gnx7

iTrader: (28)

I believe once you do a stroker crank you lose the factory oil squirters in the block due to interfence. You better check on that.

If you do... then it would be better to simply run an LS3 block and add the squirters/billet main caps. The only difference after that is the LS9 block runs slightly larger head studs/bolts than the LS3. If you are staying N/A there really is no need for the added cost of the LS9 block IMO. You can get an LSA block which is essentially the same for a lot cheaper.

My buddy runs an LS9 block, LS3 crank, aftermarket rods/pistons with MAST LS3 heads up top, factory wet sump setup with an 88mm turbo. It hasn't had any issues and it has been driven hard every time it gets taken out.

98 MECHAM TA

iTrader: (1)

Yes, I have the LS9 block.

98 MECHAM TA

iTrader: (1)

I already have the LS9 block though it was given to me as well as most the other internals and top end. Thats my problem this crank is being custom cut. Thats why I need to get it right.

98 MECHAM TA

iTrader: (1)

I'll have him check out the ls3 crank size. Makes sense to me, and I'll ask him about the squirters. Thanks for pointing that out.

A_VAS

iTrader: (16)

You can get custom squirters from Lingenfelter or Katech to fit a 4" stroke. they run about $400
but if you are running the factory rods/pistons you will need ~3.622 stroke

427 zeo6

I hope your crank guy dosent get a hold of a dry sump LS3 crank....The manual transmission Corvette Grand Sport from 2010-13 used a dry sump system just like the LS7/9 and yes the crankshaft is 1" longer than the wet sump motor ( this is a forged crank the normal LS3 has a cast crankshaft. ) Are you uing the LS9 9 bolt flywheel pattern? I wouldnt!

98 MECHAM TA

iTrader: (1)

I did not know that about the ls3, I thought only the ls7 and ls9 were dry sump. That would have just added to the confusion lol. My father in law is helping me build this motor. He works for Earnhardt-Childress Racing, and he is having the crank custom cut at his shop. I was just going to have him look into a production crank for size info. Everything is pointing towards the short snout so that is what I will tell him to do. Does anybody know the actual length of it?

oldcop

I recently read a thread talking specifically about the difference in crank length on one of the G8 boards. It was in a discussion on a new forged rotating assembly that was ordered and the crank was shortened by like .89?? I'll see if I can locate it.

98 MECHAM TA

iTrader: (1)

Thanks!

schul274

Did you ever figure this out? I'm at the same point basically. I have an ls9 crank that I plan to have shortened. wondering how the build went.

96 Comp T/A

iTrader: (8)

If it has a factory GM "Dry Sump" The crank has the long snout. Aftermarket dry sumps are driven off of a belt that goes in front of the dampener, and use the short snout, as do factory wet sump engines.