CR and Spacer plates

[ORANGEBLK08BUSA]

OK, Older Gen 99-07 busa's had CR of 11 to 1 and to lower stock piston CR for Turbo use , a Spacer plate .080 was used.
Now , with Gen 2 having a 12.5 to1 CR what size spacer would be used to bring CR #'s
down to safely boost 10#'s or more?

[Pinky]

in my opinion i feel you could add a .125 spacer and be able to run 10 pounds safely with the right tune

the .08-.09 spacer drops the gen 1 i believe 1 point

[ORANGEBLK08BUSA]

As always you come thru ....using .125 spacer and .030 HG would /could i be able to use same Timing chain.
What would be the biggest/thickest spacer before any issue.

Thanks.

[Pinky]

that would be the max spacer i would use
if it came down to it id swap the pistons for low comp je pistons
i am not sure on the length of the chain on the 08 so that is something i cant answer at this time

[ORANGEBLK08BUSA]

Pinky,

Thanks ,and I do appreciate it.
Trying to get all bases cover'd with motor before kit install and its looking like New JE"s turbo pistons and .090 spacer /gasket combo would be the Ticket.
I would guess chain would be same length as older Gen and do remember guys having issue with cam install going with taller spacers.

[Pinky]

by the way the valves and valve springs cant take alot of boost
so they will need changed if you are going to go over 5-6 pounds of boost

[ORANGEBLK08BUSA]

by the way the valves and valve springs cant take alot of boost
so they will need changed if you are going to go over 5-6 pounds of boost


Yes! Sir, Those will be also done....:thumbs up:

[WITCH HUNTER]

I have now built 2 x 08 Hayabusa turbo kits.
To keep the higher compression under control, use JE turbo pistons,100 thou spacer plate,cometic hp head gasket. In stage 1 and stage 2 systems both had excellent low down drivability.

[OzBooster]

What engine management and injector/reg , any probs with two sets of injectors ?