I'm in the process of going 20b. Currently waiting on parts to arrive and to pull out/sell my current setup.

I've got an ACT 6 puck and XT PP with around 1000 miles that I've used on my 13b at 525rwhp. Holds like a charm and drives perfectly fine for my taste. I care nothing about the harshness of a 6 puck. At this point, regular face clutches feel boring

Now, regarding the 20b. I plan on making a realistic 550-650hp. I'm building the setup to support 800hp for future room to grow but my primary goal is the get up and running. Now, I do realize that the 20b will produce significantly more torque.

Is a twin plate absolutely necessary for a power level of between 550-650hp for the time being? If so, I guess I will go ahead and lock one down. I've already been told by a well known shop that I'll destroy the 6 puck immediately. This is very likely true, but I want to hear double check from everyone else. I don't always go with the first thing I hear. Shops do like to sell $2000 clutches

I was just hoping to reserve $2000+ until after i finish, which could be my safety net in making sure I finish this build within the budget. I don't want to wind up with a 3 year down time waiting for more cash in areas I didn't expect.

Thanks again to the best forum on the web!

 

Shop around exedy are the only guys that do them, I personally would get one now.
What box have you got behind it?

 

As of now the stock trans. I have an extra waiting to throw in and maybe buy a few more

I'd love to drop the cash on a t56 conversion. Hell thats almost the price of the freakin twin plate Just need confidence that i can finish this swap first. Dont want to overextend.



Actually, I've seen some twin plates offered for FD by Spec and Clutch Masters

 

Shops make more profit selling a $700 ACT then they do on a $1800 Exedy Twin disc.

I do not make recommendations about a part if it is not needed to support a particular HP level. You can wait until you break your clutch to upgrade, however it usually happens at a time/place that is very inconvenient. 20B conversions are not the place to cut corners.

TRWeiss1's ACT 6 puck , 500hp 13B on his very first practice launch.

 

Looks like he pre-loaded/staged for too long. Saw a Honda do the same thing at a drag meet.

I would recommend a twin disc just for added personal insurance.

I'm a car nut to the 10th degree, so I have a twin disc in my diesel truck and my drag civic. Only reason my RX7 doesn't have one is I don't plan on having a lot of power.

 

I have a ACT single sprung 6 puck in my 400rwhp FC.

I have Exedy twin sprung 6 puck in my 270rwhp FD (was thinking along same lines as you- might as well upgrade it now while its apart).

I would stick with the single for now in your situation.

The single still slips a bit between shifts and this is going to help your transmissions last a little longer.

While the twin is easier to drive and modulate if you accidentally release the clutch too fast it shocks the drivetrain incredibly hard because it slips so much less.

Your transmission is your weak point, my advise is to protect it.

 

Either way you go you could prolong your drivetrain life with a clutch slave damper.

You could grab a stock one off something like a 240 or get an adjustable aftermarket one for drag racing.

This will slow the clutch release rate and save your transmission/power plant frame/drivetrain from shock loads.

 

Thanks, I agree with you, not worth the risk to find out. Ill be ordering a twin plate.

Do it right the first time or don't do it at all.

 

I ran a single disk 6 puck XTD in my 20B FC for years with anywhere from 550 to 620WHP (at least 2 years and 10k miles at 575+. Never had any problems except a sore calf muscle. I was using the same ACT flywheel shown above.

Clutches are not rocket science, and just because you can spend money on something fancy doesn't mean you have to. I would recommend calling ACT and asking them directly.

IMO, if you are using the stock trans, I definitely would NOT spend money on a twin disc right now, for two reasons. First, you are going to kill transmissions anyway at around 600whp (ask me how I know). Second, when you do decide to go to a T56 or other strong transmission, you will likely have to change clutches anyway, so why not wait until then to drop $$$ on a fancy clutch. Keep in mind that when you do the swap, you can always go to a tilton type clutch which is cheap, rebuildable, and can be set up for any torque requirement.

 

FC trans are not as strong as FD, period.

I have been making well over 600whp/500wtq for 4+ years, same stock FD trans I started with (even though I have multiple spares just in case). Exedy twin disk, aluminum driveshaft, carbon LSD, Chromoly Axles, etc. Absolutely no whines or grinds.

 

4 years is nice but, what about your mileage? I think mileage is the determining key factor in longevity comparisons.

 

This is a great point. Its a toss up here. I plan on definitely surpassing 600whp, however, I do not intent to launch this car. I also do not daily the car or ride the 6 puck in traffic. Strictly interstate games/rolling on throttle until I've supported the rest of the drivetrain.

Thanks for the info. Def considering the 6-puck, I have the ACT flywheel, XT PP, and a clutch with 1k miles on it. Just worried about safety, my primary concern; exploding flywheel/clutch parts are not worth it.

 

Scatter blanket

 

Thanks for the input, I think I may try out an HKS GD Max Twin Plate

 

I would make sure parts are readily available and reasonably priced for whichever option you choose.

Exedy over HKS in this regard in my opinion.

 

This really should not have much to do with clutch choice. If the clutch is underrated, it will slip. As long as your clutch is not slipping, there is really no more chance of it exploding than there would be with any other.

As mentioned if you are worried about this, a scatter shield is the solution. Even with the best clutch in the world, if the input shaft breaks, it will still make a mess. A scatter shield will also hep protect you if you blow apart the transmission.

 

Good point.

I have found a steal on an HKS almost new sprung unit. Could be a scam, but we will find out. Rebuild kit can be had around $700 which isn't too shabby. Rating is 600tq/600hp. There's just not alot of support throughout the rx7 community on this clutch.

 

Good info. I've been next to a car blow a rod and metal through the block across a street. Unrelated, but super paranoid ever since. I'll look into a scatter blanket. Cetainly can't hurt.

 

Twin-plate arrived; problem solved!