Project GatTagO

iTrader: (7)

Yes, the extra mass of the flywheel can absorb more heat than the little button flywheel. There is really no such thing as the perfect clutch for all applications. There are trade-offs that must be considered based on the type of car that you are building and what you will be doing with it.

Andrew

SPEC-01

iTrader: (2)

The tolerence of heat and its dissipation and the mass that I mention above are the primary benefits of a complete flywheel versus a button assembly.

GIGAPUNK

iTrader: (2)

What do you guys think about ducted air cooling to a small clutch? Something along the lines of a brake cooling duct drawn from the cowl area maybe. Good idea? Waste of time?

Project GatTagO

iTrader: (7)

It might work. I have never seen it done on a race car, but then again race car drivers are taught not to slip the clutch. Most racers will run the smallest clutch that is allowed by the rules in the lightest material that is allowed (carbon/carbon) being the lightest.

You are asking a bunch of questions, but how about telling us exactly what you are trying to accomplish?

I think you have a 240SX right? LSx powered obviously. What do you intend to do with the car? Is it a street car? Is it a race car? Is it a street car that is sometimes raced? What kind of racing? Etc....You get the idea.

Andrew

GIGAPUNK

iTrader: (2)

Originally I was building the car to Redline Time attack (road racing) "street class" rules. But the rules have changed so drastically every year that I've decided to just do whatever I feel like. The car will not be a daily driver, but I'd like to go out Saturday night, or drive to the autocross without a trailer. It does need to survive the street. But the interior is stripped, there'll be a 6pt cage, and no A/C.

I plan to participate in just about every type of motorsports I can. I've been autocrossing my s/c miata, before I sold it, this past year, before I sold it. I'd like to do that again. I'd like to earn a road racing competition license through HPDEs, etc, and participate in Redline and NASA time trials. I plan on doing some top speed runs. Maybe even Targa Newfoundland someday.

The car should weigh ~2600 lbs. I'm building a 404ci L76 with a 230/240 ish cam. I expect it to put out about 585hp and 490 ft lbs at the crank. I'm rebuilding a T56, and the car came stock with 4.083 R&P out back. I'll start with almost R compound 275 section width street tires, but I'm sure an extra set of 315 or 335 hoosier A6 autocross tires will find their way on there eventually. The focus of the car is handling. I'll eventually get out to the drag strip just for kicks, but I'll never set the car up for the quarter mile.

Thanks for your input everyone!

I realize that carbon/carbon solves all my problems, but I'm trying to brain storm on how to do this for $1000 or less.

Project GatTagO

iTrader: (7)

If you plan on driving this thing on the street at all, then trust me, you don't want a "race" clutch. Race clutches are designed to be serviced on a regular basis and something tells me that you don't want to be dropping the trans on a monthly basis.

Given your goal of being under $1000, I would start with an aluminum flywheel and add your favorite clutch (single disk, stock diameter) that will handle the power that you are making. Trust me, you will be much happier with that set-up than with a clutch that you have to pop at every light.

Andrew

SPEC-01

iTrader: (2)

Routing cool air in could certainly help reduce temps. This would require some modification to the bell-housing of course, but it might be worth it.

Temps really shouldn't be that high during road-race usage though. So, getting a clutch that provides you with the correct capacity and design for your planned usage should be all you need. Excessive heat is the result of slip, which occurs when the clutch is over-powered, or the pedal is riden. This shouldn't be an inherent issue with a road-race car though if it has parts that suit your needs and as long as you drive it with some sense!

GIGAPUNK

iTrader: (2)

That is definitely sound advice. I just keep wondering how much I can reduce the MOI, while retaining some slipability by running organic or cerammic 8.5 discs. They will hold my torque. So it's just a matter of getting enough heat tolerance. But you're right. I don't want to rebuild my clutch every month. But Every 15-20k miles wouldn't be the end of the world.

SPEC-01

iTrader: (2)

I suggest something like our Stage 4 kit, with an Aluminum-Plate and our Aluminum flywheel which will be very light and ideal for road-race usage. This will be a great option with tremendous weight reduction over the stock parts.

GIGAPUNK

iTrader: (2)

Thanks J, thos aluminum pressure plate options, sure are sexy.