AU N EGL

Hey Guys

Looking for rotating assmbly sugggestions.
Most likely need 12:1 compression on 100 octane. and rpm range to 7500.

crankshaft wt no less then 20.41 kg and hopfully not much more.

Building a LS2 block with GM LS6 heads 88958622, GM Cup cam 88958606
, dry sump oiling. fast 90 intake and tb.


TIA

Tom

bichin95redta

How much money do you have? The stock crank should handle the C/R & RPM you mention, although I have no idea what the crank weighs.

If you're looking to twist at 7500, I would go with a forged rotating assembly. I bought the best I could afford, and it cost me around 2 large. That doesn't include bearings, or piston rings. You could easily spend twice that much.

Callies, Lunati, Eagle, Ross, Mahle, (I'm not sure if Scat makes forged cranks for the LSx-series of engines) and many other companies make good-quality, forged rotating assembly components. It just depends upon how much money you have to spend.

AU N EGL

Thanks. Dont have an unlimited budget, but not constrained either. I will look at the names you mention.

TAF Motorsports

iTrader: (10)

Use a stock crank unless you want to spend upwards 2k for a lighweight Crank

Scat 6.125 Rods ($280-$290)
Manley Flattops -2cc ($550)

It will net 12:1 and your DCR will be at 8.8 right on the edge of pump gas, higher octane may be recomended.

Probe makes a nice lightweight 6.125 I beam as well for about $450.

chriswtx

iTrader: (5)

are the scat rods LS1 on center rods??

AU N EGL

The stock crank is 22.45kg. Can go down to 20.41 kg on the crank.

I will look at the others that you mention.

Thanks

J-Rod

Ok, are you limited to steel rods. If not, look at Aluminum to lighten rotating mass.

If you want a light crank, you can look at HTC or Callies. If you want to lighten your stock crank up, send me PM. I can point you to a shop that will recontour your stock crank and take weight off.

As for light steel rods. You can do a Probe I beam our were about 550 grs. Most other are about 580+. Probe pistons are nice and light also.

Here is a silly question, why are you using the Cup cam and the GM heads. Unless you are limited by class restrictions, there are much better combos out there.

AU N EGL

Not a silly question, that is what I am building a World Challange engine which requires those spcific parts. Just not sure I wont to put out 22 large for a Katech WC engine just yet.

These spcific GM heads seem to flow better then most others on the market. Info on head: http://www.sdpc2000.com/catalog/1979...cc-Chamber.htm

The cam, well I can see how that maybe imporved and that 106 LSA is kinda nasty but that is what the rules require.

Rods and pistions are open, but the combination of rods, caps bolts, piston, rings, pin, clip and bearing may not be less then 1190g. stock is 1308g.

Once I get all this info put togther I may find that 22 large is a good price. But until then.

Most of these LS2 WC engines put out aprox 550+/- flhp.

J-Rod

I thought that might be the case, but I wanted to check. LG builds his own WC engines, so I'm sure you can do the same and be competitive. Also, you probably don't need to shell out 22 large.

TAF Motorsports

iTrader: (10)

I do believe the engione will need to be certified and sealed by SCCA. I'd call Lou or Jason and SCCA tech to check.

AU N EGL

Yes it will. There is SCCA tech inspector that lives in my area and I have the details. This engine would be used this year NOW while the challange car and 2nd engine is built for 07.

J-Rod

For our Probe setup here is what I have for weights.

TAF Motorsports

iTrader: (10)

keep us updated on your progress

AU N EGL

Will do guys. Thanks for the help and info.

Tom