To build or not to build

[turbojonn]

What do I need to know about building a GS 1100e motor, 1981?
I would assume undercutting the transmission is a must as well as swapping the crank for an 83? Are there certain models of cranks that are more desirable? Do I need to use turbo pistons or can I just use a spacer plate? Looking for 300 hp, dyno queen, not much drag racing.

[Gregory]

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[geek]

What do I need to know about building a GS 1100e motor, 1981?
I would assume undercutting the transmission is a must as well as swapping the crank for an 83? Are there certain models of cranks that are more desirable? Do I need to use turbo pistons or can I just use a spacer plate? Looking for 300 hp, dyno queen, not much drag racing.

I think the 300HP is doable. What sort of budget do you have?

[blowerbike]

this will blow a budget fast going from scratch.
i'd look for a used engine with all the good stuff from someones drag bike they are parting out.
some years ago i sold a 1260 turbo engine for 2500.00 valve cover to oil pan.
if you do go from scratch look for as much good used stuff as possible and save a bunch of money.
i do have some good stuff left over if you if go that route.

oh,
300hp from an FF draw through won't be that easy..no matter what anybody says.

[geek]

FF HAHAHAHA Get your time machine out!

[blowerbike]

FF HAHAHAHA Get your time machine out!

the man has an FF40 kit on his bike.
i don't think he is going change over to injection on top of the engine build...
what do you think?

[geek]

I think I'll let the OP speak for themselves.

[turbojonn]

Oh man, wish I was the one who bought that motor. I don't want to spend more than 2 thousand or so. Maybe it's not to be.

[turbojonn]

Yah, I'll just leave the carb on it. It all depends on what parts I find. If the project is too expensive then I'll just leave the bike in poser mode.

[geek]

How much have you invested in the power plant so far? Or is this basically a stock engine?

Is the chassis basically stock as well?

[turbojonn]

The motor is stock except for a coat of krylon semi flat and a welded clutch basket. There's a 929 front end and a gsxr 750 rear end.

[rapidray]

To do it CORRECTLY, you need a big left end welded crank, turbo specific pistons, the trans cut, studs top & bottom& the oiling system set up to make the turbo live. As in clean oil & an oil cooler. You will be into it for around 2K just with the parts. Can you build the motor yourself & degree the cams? REALISTICALLY, with the parts you have now, I have to agree with Terry in that 250-270 is a more feasible power level with the system you already have. You have suspension & brakes already so that is a GREAT thing!
Ray.

[turbojonn]

Thanks for the replies. I've always wanted to build my own motor. I've done lots of turbo kits and one top end and assorted small stuff. This would be a fun winter and spring project. Oh, 250-270 would be fine, 300 just sounds nice.

[turbojonn]

Regarding the tranny, undercut all, or just second gear?

[jimb12]

For ~250hp you will definitely need straight-cut primary gears along with a welded crank and modified clutch basket.