I currently have a GSR with JR and 6lb boost pulley. I am wanting to upgrade to 9-10 lbs.

Correct me if im wrong, but I know the stock bore is 81mm but i am unsure of which thickness head gaskets would be safe to use. I am also concerned about lowering the CR. will this lower my bottom end, or will the greater boost compensate for the loss.

Please give me some feedback. Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by prennro &raquo;</TD></TR><TR><TD CLASS="quote">I currently have a GSR with JR and 6lb boost pulley. I am wanting to upgrade to 9-10 lbs.

Correct me if im wrong, but I know the stock bore is 81mm but i am unsure of which thickness head gaskets would be safe to use. I am also concerned about lowering the CR. will this lower my bottom end, or will the greater boost compensate for the loss.

Please give me some feedback. Thanks</TD></TR></TABLE>

Yes you can go 9-10lbs on Stock GS-R motor, Max I would go is 15psi. But yeah with good tuning anything is possible.

If you want to be safe you can get the Cometic head gasket 0.43 to lower you compression for boost applications.

When people say lower compression, they do not mean Lowering their bottom end. What they mean is the way the piston is made, If it's domed then it will have a higher compression, if it's dished then it's lower compression.

 

My bad, I gave you wrong information

It's 0.030in, 0.040in and 0.054in the 0.030in is equilavent to stock so the next step(thicker) is the 0.040in.

 

Thanks for the info