Classification change with forged motor?

[agrabau]

Hi Everyone, I had a great time at NHIS last weekend.

I'm in the process of building a new motor for my STGT car with forged pistons. I wanted to know if this will bump me out of STGT. The compression is the same. All other aspects of the motor will be unchanged My motive for doing this is twofold the "7 bolt" 4g63 motors are prone to a condition called crankwalk wherin the thrust bearing goes out of spec and the main bearings all spin.

I'm rebuilding with a earlier crankshaft of equal dimensions but using a better, early thrust bearing design.

I'm also planning a weld in 8 point cage which is on the way, and by the looks of it the cage, as long as it doesn't pass through the firewall will be legal still for STGT but I wanted to confirm that.

So, in summary, the motor is same power, factory boost at 1 bar same old turbo but forged pistons for reliability (figured while I was in there...)
It's going to be in the car for the Summit Point redline time attack I hope and I'm not sure how many COm events are after August but I wanted to check in advance.

Thanks a lot,

Alex Grabau
www.dentsport.com
Evolution II Mitsu with world's loudest squealing tires.

[offcamber09]

Welcome to SP.

[WillM]

Scott is correct. Any non-OEM modifications to the motor will put the car into SP. In your case, SPB.

Cheers,

Will

[agrabau]

I thought so! Thanks guys. I guess I've done my last event in STGT.

See everyone soon.

[Crusin]

Even though you have not improved the engines HP or performance, you have improved its' reliability. There is an old adage, you must finish the race to win. Sorry, but SP it is......