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-   -   Flywheel and clutch recommendations? (https://www.rx7club.com/race-car-tech-103/flywheel-clutch-recommendations-281506/)

RX-Midget 03-11-04 07:49 AM

Flywheel and clutch recommendations?
 
I'm getting ready to purchase a lightweight (13lb) Centerforce flywheel for my car that uses a '86 NA 13B. How big of a difference will there be from the stock flywheel?

How much better/worse will the 8lb aluminum flywheel be?

Any problems with the aluminum flywheel's due to the dissimilar metal expansion rates (aluminum and steel)?


Uses include auto-x, track days and street use.

Oh, I also need a clutch. Any recommendations? I want a sprung center and probably a marcel for street use. I also need to keep the pedal pressure almost the same as stock due to the non-stock pedal arrangement that already has a heavy pedal feel. Power is about 220hp, car weighs about 1600lbs.


Thanks,
B.

mikey D 03-11-04 01:10 PM

rx midget
This is what i use and love it

stage 1 organic disk and pressure plate by
clutch specialties
rb alum flywheel.

Its lasted thru 2 years on my 12a racing the shit out of the car and it is still holding power on my turbo motor.
the pedal pressure is very slightly increased and very very easy to controll the motion. There is no clutch chatter that heavier 6 puck type clutches have.

the alum flywheel is great. it has a friction plate on it so you just replace that instead of removing the flywheel and resurfacing it. 10-30mph cruising can be a little rougher than a stock flywheel but its not to bad.
the engine will rev very very fast. you will definately accelerate harder than before.

with a super light flywheel there is more chance of bogging when starting from a standstill but a good driver will have very little problem.

they also make a kevlar clutch disk that is very nice. Downside is it costs a bit more than the organic and doesnt last as long in my opinion.

A shop suggested i try one of these clutches about 4 years ago and i have used them ever since.

MADBOOST 03-12-04 12:35 AM

i have a bonez chromoly ultra lightweight flywheel from rx7,com in my fd that only has about 5,000 miles on it and no hard shifts(since ultralgithweight flywheel launches and shifts are so weak anyway) i paid 650 for it new and i recently bought a AE86 for drifting and am rebuilding my FD for drag... so if any1 is interested i will sel it for 400 or work out a trade with a heavier flywheel in new or near new condition.... by the way, my fd is stock besides clutch and fly so there was barely any wear on the flywheel



MNRE_investors@yahoo.com

Blake 03-12-04 11:56 AM

My favorite street clutch is Racing Beat's Heavy Duty Street and Strip clutch and pressure plate. No marcel is a benefit, not a drawback. In other words, it just feels so much more crisp and precise than a mushy stock clutch. I knew right away that I liked it, but my appreciation for it soared a few months later when I drove a friend's car with a brand new stock cluch, back to back with mine. Night and Day difference. I also think it is about the lightest pressure plate that could reliably handle 220 hp, presuming you are not drag racing it.

I think the difficulty of driving a light flywheel is exaggerated, to say the least. Any competent driver will make the adjustment quickly and, unless you live in San Francisco, it's a big non-issue. However, I'm the guy who drove a race-prepped 1st gen with peripheral port 13B and a 3 puck clutch from Portland, OR to Gainesville, FL and back, pulling a trailer...so, my idea of streetable might not be the same as yours. ;)

RX-Midget 03-12-04 02:09 PM

OK Blake.
So the marcel is not neccesarry. I just figured it would take a little load off the driveline, but it sounds like just a sprung hub woiuld be OK. How much more pedal pressure is needed for the RB S/S set up? 10%, 20% more?

I understand your idea of streetable.I'm about the same. The car is tagged for street use :D

Blake 03-12-04 10:54 PM

Nice! I couldn't tell you what the percent difference in pedal pressure was...my leg is not properly calibrated and it was a couple years ago that I had that setup. Lately, I haven't driven any rotary without a puck clutch. I do recall that it was noticeable, but not significant. When I drove the stock clutch, however, it seemed like a can of creamed corn.

BTW, no marcel is actually better for the synchros. :)

RX-Midget 03-13-04 09:42 PM

What do you think of a 6 puck, sprung center clutch with a stock pressure plate?

Will it hold? Will it be an "on/off" switch?

One of my auto-x tricks to try to get out of a corner faster when I just don't have the right rear axle ratio is to slip the cluthc a bit and keep the motor in the power. Will I still be able to do that?

Blake 03-14-04 12:17 AM

I don't like sprung hub puck clutches. They are half-preganant, if you know what I mean. I do like solid hub puck clutches with light (stock or mildly upgraded) pressure plates and decent gearing (e.g. 4.88). If slipping a puck clutch is even a consideration, then seriously consider calling Pineapple Racing (503-233-3878) and talk to Rob Golden about the special friction material he helped develop for his puck clutches. Rather amazing stuff and surprisingly affordable.

elwood 03-14-04 08:42 AM

With this talk about marcels and sprung hubs, I think there may be some confusion.

Marcels are the wave-type springs that live between the friction surface and the clutch disc. They ease clutch engagement by making full on to full off a more gradual transition.

Sprung hubs are the coil springs inboard of the friction surface. Their sole function is to quell engine surges from combustion pulses. Contrary to common belief, they do not ease driveline engagement or lessen shock loads to the driveline. These springs don't have enough rate to do that. When you dump the clutch, these springs immediately go to coil bind and you effectively have a solid disc.

Therefore, marcels make for smoother launches, and sprung hubs make for smoother cruising.

I've run just about every type, and I like the RB lightweight steel flywheels, with street/strip pressure plate and the matching clutch disc. I like the race versions even better (pucks, no marcels, unsprung hub), but I've heard the durability isn't as high (especially for street use), and I don't like changing clutches.

BTW -- lightweight flywheels allow you to shift quicker, which is my favorite benefit.

RX-Midget 03-16-04 08:54 AM

Well,
I found that the RB light weight Aluminum flywheel is actually made by Fidanza and re-sold by RB, Mazdatrix ect...
Best price I found was $300 for one fitting a '86 NA(w/o counterweight). I will probabaly order it from CV Products ( CV4.net ) for $319. I liked there salesman (Carl) and I think they had great service and knew the products. He also knew and sold products to SDJ and several other respected shops, so I have more trust in his company rather that the internet special where I found it for $300.

I am waiting for Carl to get back to me about an Exedy clutch they sell, but I may still go with a Mazdatrix HD, S/S clutch and PP.

I wonder if the Mazdatrix HD, S/S clutch plate would work well with a stock style PP?

UltraRev 01-09-05 04:22 PM

We have the Fidanza Aluminum flywheels in stock ready to ship give us a call toll free 1-877-858-7272 or order online: http://www.ultrarev.com/ecart/shopexd.asp?id=18595

ACTman 01-10-05 11:16 PM

[QUOTE=elwood]With this talk about marcels and sprung hubs, I think there may be some confusion.

Marcels are the wave-type springs that live between the friction surface and the clutch disc. They ease clutch engagement by making full on to full off a more gradual transition.

Sprung hubs are the coil springs inboard of the friction surface. Their sole function is to quell engine surges from combustion pulses. Contrary to common belief, they do not ease driveline engagement or lessen shock loads to the driveline. These springs don't have enough rate to do that. When you dump the clutch, these springs immediately go to coil bind and you effectively have a solid disc...QUOTE]Amen. It's good to see someone who knows what he is talking about. Thanks!

turbo80cid 01-14-05 07:28 AM

I have the ACT pro-lite flywheel and the heavy duty pressure plate with the un-sprung 6 puck clutch. I have only drove this combination a round the block twice.
So far I like it but like I said I have not driven very far. It rev's very quickly and the clutch is a little grabby but not to bad.

diabolical1 01-15-05 11:49 AM

ultrarev ~

1986 is the earliest model year on your dop-down menu and i'm kinda looking for a flywheel for my car, too. do you sell any for the 1984-85 13B engines?

$300 is definitely a good price. however, one thing that concerned me with the www.cv4.net site is that they had the 1986-91 engines lumped together. shouldn't there be a distinction made? they have different front counterweights, don't they?

RacerJason 01-16-05 07:24 PM

The ACT models (ProLite and StreetLite) offer two good options and are priced lower. I contacted them about prodeal's or contingency offers and they dont' offer anything unfortunately. :-( Still a good price though for a solid product.


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