TOPIC:

As a little sideline to my 750 dabblings a GPz1100 motor is coming my way. Now I don't know too much about the big engines, but I'd like to start collecting parts to turn it into a monster turbo motor. The turbo parts themselves (headers, turbo, EFI, plenum etc) are easy enough, but what would be on your wish list of internal motor components? I'm looking at 1200cc minimum, 400hp+, so let rip with your fantasy shopping list please...

im not sure about the j/gpz series of motors but heres a partial list of what is slowly progressing on my 1385 turbo motor welded crank,heavy duty 2nd gear with undercut trans,braced maincap,blue printed oil pump with rear pickup,heavyduty studs top-bottem,bigblock with 1385 bore:evil: ,heavily breathed on dual plugged gpz head,cams are still being debated,on of course theres that rajay turbo mounted in front of motor(got that idea from your bike!

paging fastest z1,paging doctor z1!

lorcan,

this gonna be a race-only engine, or street/race, or just street?

--r

What, no CVT, dynamic cam phasing, or ceramic bearings?

Race only, drag & top speed (1.5 mile run).

gonna run efi or a draw-thru?

silly question... i'm talking to lorcan. 8^)

i'd intercool, or run methanol on this, more displacement, probably about 8/8.5:1 c/r, not a ton of head work, but larger valves, good cams(no suggestions, sorry), larger a/r turbine, hell larger turbine in general.

how much boost? 20-30psi?

basic lower end work, more for durability, and simplicity for those 1.5 mile top speed runs. lighten the crank a bit, good fasteners.

i'd set up the injection like we're gonna do with wires street bike. one big plenum, and a larger automotive throttle body. 550-800cc fuel injectors. maybe an extra pair that come on under high boost for supplemental fueling(like my subaru ej20g type ra engine had).

what's the timeline look like?

meaning, when can we see this beast? what chassis is the going in?

--r

I basically just want to swap the 1100 motor for the 750 motor once it's all built, with a bigger turbo and injectors etc obviously, and just duplicate what I've done with the 750. So race gasoline, intercooled, street tyre, 30psi. It's the "basic bottom end work" I'm stuck on as I don't know my way around the roller bearing motors, plus any reliability issues with going 1200cc and larger.

No timeline, I just want to start collecting suitable parts (cheap) as and when they come up.

well in my experiance bigger tends to be better since the bigger motor can make same power with less boost and lower rpms ,smaller cams which is gonna make life easier on motor.

Lorcan;
which Gpz motor are you geting?? 81-82 or 83-84
83-84 would be the best IMHO it has a stronger tranny and 18mm piston pins not to mention the better combustion chamber and larger valves.

you will need to go with shim on bottom lifters if its 81-82,a lot of turbo kaws use the true J model cams or for big horse power the 84 gpz cams.

the head work should be minimal as you are going to be force feeding it

weld the crank,back cut the tranny,install maincap support,overshift bushing,big cylinder and case studs,I would use a seperate oiling system for the turbo(low oil pressure),you may have to double plug the head if you are going to run high boost or use a mag/cdi box

you can go out to 1166 with the stock sleeves or 1261 with the stock block w/OS sleeves, prally needs to be "O" ringed with a copper gasket or one of MTC's power ring head gaskets.

sounds like a killer project

Ever heard of Extrude Hone abrasive flow machining? You should get that done to the head! It's like... perfect porting & polishing, takes all the guesswork out of the job.



And what about tungsten disulfide coating? Microfininishing? Cryogenic treatment? There's a company called Micro Blue that does amazing things for bearing surfaces and moving parts. If you really want to get crazy with this engine you'll send it to them. With all your gears microfinished, tungsten disulfide coated ceramic bearings in microfinished races, etc etc and you start to see some very substantial power gains and enhanced component longevity due to vastly decreased internal friction. They even do drive chains and sprockets and wheel bearings...

www.microblueracing.com/custom_shop/cs_cool_stuff/crank_800.php

The big drawback is that Extrude Hone charges like $430 to port a four cylinder motorcycle head, so it's out of my reach for the forseeable future...

my wish list? a turbo unit i can actually afford!then i would like to ride wireman's or yours to see how much it will scare the hell out of me.