Porting for a turbo

well i have these parts

A welded j crank with the 16 tooth center pin
A j head
a zn1100 head
a 1200j/gpz kit wiseco 10.25 kit(new)
I have a back cut tranny and a welded basket/lockup clutch

i was thinking selling the kit, and j head and running a zn head with 84gpz pistons(buying one in the 1200 sizeand correct compression) and turboing that sucker.

should i use the gpz head or the j head and what kind of porting on the heads should be done?

street strip bike (not a wheely bar bike though)

Not sure about the turbo combo, but might be interested in the "kit".

Forced induction!
Porting not really needed.

Porting can still provide benefits to a turbo motor. Turbos increase density not flow. That doesn't mean that there are times when porting a turbo motor shows a big difference at the drag strip.

I've seen times where guys have installed turbo cams and not seen a difference either.

It's the combination and how it' setup for the intended use that matters most

If you're referring to the 84 - 85 shaft drive 1100 head, that is the same as the 83 - 85 GPz head except the temp sensor boss is not tapped.

A standard J head is different. Hemi chamber w/ smaller valves. 37/32

Any of those 3 heads with a turbo will make for a quick ride.

on a kz head go with 1 size over exhuast valve and concentrate on cleaning up exhuast ports/bowls,turbo will deal with the intake side

A 1mm over exhaust valve won't do much if the port's not setup for it There's a lot more to installing larger valves than guys think....

Larry C

So if i went with a bathtub head the head shouldn't need porting, for street strip bike is what i am taking away from this.(maybe just a clean up on the intake/exhaust?)

IF using 83 GPz style head with turbo...

Valves are plenty big enough for 1200cc.

Punch the throats out to 90% on both sides. Clean up the runners. Bolt on the turbo. Crank 14.7lbs to it and you effectively have a 2400cc motor on full boost.... That should put lead in your pencil :laugh:

Sounds good to me
Thanks:)