Kz750 Cylinders - How big can you go?

I don't know if we want to start another thread for this, but theres also the trouble of oiling. Getting the turbo scavenged wont be easy. I think maybe a GPz turbo oil pan would be necessary as well. Other than that, the only option would be an electric scavenge pump. I think these are our two main obstacles. One guy over on the 750turbo forums tried to modify his stock oiling system, and he has some skills. Couldn't get it to work, so he's going with an electric scavenge pump.

your best bet is to obtain a 750 turbo engine the cases are made different and includes a scavange pump for the turbo. use an wiesco P809B piston kit run a modified HT10b and you can make an east 150 RWHP on pump gas! doing one right now for a customer.

Any chance you can post photos of the case/oil system differences?

I've been looking around, and Mr. Turbo sells an external electric little small scavenge pump. I'll run this or something similar, and look out for GPz rods on ebay. I wont be starting the build for a year or two so I can afford to wait.

T_Dub wrote:

Sounds like these rods wont work. 4mm longer is a huge difference. I'd say we keep trying to find GPz750 turbo rods or we could investigate the carillo option.

Edit: I just emailed carillo, hopefully they'll get back to me. For the price of this build I'd be willing to buy aftermarket rods if they weren't crazy expensive.

PS - I've been investigating turbos all day, I think a GT20 would be the best bet for a 810cc engine running moderate to high boost. Lorcan runs a GT22 I believe, so for a street bike a GT20 or even a GT15 would be good I think.

T dub i have a set of 4 750 turbo connecting rods email me direct at b.flood@myactv.net if interested.

T_Dub wrote:

I've been looking around, and Mr. Turbo sells an external electric little small scavenge pump. I'll run this or something similar, and look out for GPz rods on ebay. I wont be starting the build for a year or two so I can afford to wait.

My build is on roughly the same timeline, maybe a little further out as the wife is trying to go back to school. I'm just trying to get some ideas/parts put together to keep interest going.

So, what have we decided is the max size piston that can be put in with new sleeves? I saw a CC size, but no mention of the piston size.

Also, I believe it was Steell that said the Gpz rods would work even though they were 4mm longer, but I'm assuming they would make a big difference in static compression in the wrong direction for a forced induction engine.

you could use a spacer under the base gasket that would eat up the 4mm difference and if you are going to use a turbo you could even go to like 6mm to drop the compression...

T_Dub wrote:

Sounds like these rods wont work. 4mm longer is a huge difference. I'd say we keep trying to find GPz750 turbo rods or we could investigate the carillo option.

Edit: I just emailed carillo, hopefully they'll get back to me. For the price of this build I'd be willing to buy aftermarket rods if they weren't crazy expensive.

PS - I've been investigating turbos all day, I think a GT20 would be the best bet for a 810cc engine running moderate to high boost. Lorcan runs a GT22 I believe, so for a street bike a GT20 or even a GT15 would be good I think.

We get $1295 for custom Carrillos. See what they tell you then get back with us.

Jay

hardr0ck68 wrote:

you could use a spacer under the base gasket that would eat up the 4mm difference and if you are going to use a turbo you could even go to like 6mm to drop the compression...

Probably couldn't find a cam chain for that

hardr0ck68 wrote:

you could use a spacer under the base gasket that would eat up the 4mm difference and if you are going to use a turbo you could even go to like 6mm to drop the compression...

or just have pistons made with the correct wrist pin height

I have a set of 4 750 turbo connecting rods if someone needs them shoot me an email to b.flood@myactv.net

PLUMMEN wrote:

hardr0ck68 wrote:

you could use a spacer under the base gasket that would eat up the 4mm difference and if you are going to use a turbo you could even go to like 6mm to drop the compression...

or just have pistons made with the correct wrist pin height

He is talking 4 mm. Move the pin up 4 mm and it would be in the rings, and so close to the dome on the bottom that the rod might not fit.