MR2 Roadster Owners Club

The Workshop => Performance Related => Topic started by: markiii on July 5, 2005, 15:20

Title: Uprated Clutch and Lightweight Flywheel
Post by: markiii on July 5, 2005, 15:20
In preparation for my upcoming Turbo install (this weekend) Slacey, Ekona and myself arranged some time ago a mini GB on uprated performance clutches from RPS.

We also decided that why we were in there we would add a lightened flywheel, also from RPS.

The Clutch

RPS Hi-Performance Clutch kit for the 2000+ MR2 Spyder increases the clutch capacity to hold over 230 lb*ft. Perfect for high hp naturally asperated engines as well as mild turbo upgrades.

(http://www.ppeengineering.com/assets/images/RPSMRSClutch.jpg)

The Flywheel

These flywheels utilize RPS's patent pending "segmented" heat shield system. Traditional heat shields warp because of the uneven heat produced by a slipping clutch. Just like a car going around in a circle, the outside tires go faster than the inside tires, the clutch disc slides faster around the outside of the flywheel than it does around the inside. The faster moving outside gets hotter than the inside. Because metal expands more the hotter it gets, the outside of the heat shield expands more than the inside. Traditional heat shields are made of one piece metal rings, so when the outside expands more than the inside, the only thing the shield can do is warp. The RPS Segmented heat shields are not connected so they can expand and contract without warping. A warped heat shield causes the clutch to slip, which causes more heat and more warpage.

RPS Billet Flywheels are dynamically balanced after CNC machining. Other flywheel manufactures assume that since they CNC their flywheels it comes off the machine fully balanced. This would be true assuming the density of the aluminum is constant throughout the part. Unfortunately even the best billet material is not evenly dense throughout and the starter ring gears are never perfect.
RPS Billet Flywheels are also fully rebuildable for the life of the car and can be up-graded to Carbon-Carbon at any time.

Flywheel Weight: 9 lbs.

(http://www.ppeengineering.com/assets/images/MRSflywheel.jpg)

These are the same items used by mph on his SMT Turbo with no problems for teh last 2 years. So we new we were buying with confidence.

Thanks to Paul at PPE for sorting us out with a good price.


Installation.

Those that know me will probably be expecting that I installed these myself. However as it's an engine and gearbox drop job to install and Dan managed to find us a very good garage to install them for a bargain £260 inc vat, I decided to let the proffesionals handle this one, as it would have been a 2 day job for me. Worth noting I had this done pre-turbo as doing so afterwards is more work as you need to remove some of the turbo plumbing.


So a week or so ago I took a day off and went down to C J Eley in Braintree for teh install to be done. (Thanks to Phil4 for chaufering me around)

In addition to the clutch and flywheel I was also armed with a new Toyota throw out bearing, new flywheel bolts, and 2 quarts of Redline MT90 Gear oil. (You will need to replace the Gear oil when doing this job so it may as well be with good stuff).

Below you can see the new Clutch and Flywheel along with the old stuff that was removed.

(http://www.mr2roc.org/Repository/misc/pictures/inforumposts/new.jpg)
(http://www.mr2roc.org/Repository/misc/pictures/inforumposts/old.jpg)

Minor point to note is that the new flywheel is a hairs breadth wider than the stock one which neccessitates a minor trimming of the plastic guard that keeps the flywheel protected from any crap thrown off the road. It's really no big deal though.

So whats it like to drive?

The Clutch;

Surprisingly and Dan can back me up here (his is teh same) for a performance clutch it's actually far far lighter than stock. I was expecting some really heavy noticeable difference. If anything it's a lighter change than stock, and teh biting point caused no issues either.

Flywheel;

For much of the time the Flywheel seemed to make no difference however areas that you can see teh difference in are;

1. Holding the car on the clutch on a hill, this is a little more tricky but an hour or so soon has you used to it. You will need a few more revs but nothing major.

2.  Startup and shutdown, the engine sounds noticeably more eager when you start it, and correspondingly now stops dead the instant you turn it off.

3. Idle seems a little lower.

4. Rev matching on teh downshift now requires very little effort.

5. And the important bit, 1st and 2nd gear are now so much more fun, you really can feel the extra oomph.

Redline Gear Oil

Surprisingly the biggest difference of teh day came from teh gear oil. I cannot reccomend this too highly. Any notchiness has now totally dissapeared changes are smooth as silk and you can almost just punch teh stick from 2nd to 3rd. Gear changes are now a positive joy.

So would I recomend it?

Tricky one that. At £250 to install it's not a cheap mod. In my case a neccessary one as teh stock clutch won't last long with my turbo in, for an N/A teh clutch is probably uneccessary.

However if your doing teh flywheel you may as well do this too, the labour will be the same.

The flywheel is worth installing if you have reason to be in there (i.e new clutch) but I'm not sure you'd want to pay nigh on £500 (parts and labour) just to install teh flywheel. It's good, but it's your money and your choice.

The gear oil is an absolute must at circa £50 including getting it changed it will make a huge difference and I would definately do so if I was staying N/A.

Write up of teh Turbo coming soon!
Title:
Post by: heathstimpson on July 5, 2005, 16:07
Excellent informative write up Mark  s:wink: :wink: s:wink:
Title:
Post by: Anonymous on July 5, 2005, 16:16
I pretty much second everything Mark says above: After I had the install of the two parts done, the one thing I noticed more than anything was the ease of the action on the new clutch. It's a hell of a lot easier on the left leg than the stock one ever was, and is especially noticable if the MR2 is not your daily driver (indeed, if I hop straight from my car into my Ford Ranger, I really have to struggle to adjust to a heavier clutch again!).

Which brings me nicely to my next point...

Regarding the flywheel, I was slightly disappointed that I didn't notice any huge difference with it on at first. However, after Mark let me drive his '2 (before the clutch/flywheel change) a few weeks ago, there really is a world of difference between stock and the RPS one. It's every bit as good as Mark says.

One other thing to possibly bear in mind are the benchmarks that I've achieved since the swap. At the dyno day in Witham that myself, Mark and Adam went to, my car managed a full 5bhp more at the fly than Mark's (bearing in mind the only realy differences between us engine-wise  is that he has the known-performance-increasing H&S exhaust and I have the cosmetic-only TTE one). I also used to be able to get 0-60 times of around 6.7-6.4secs with the stock items: I've since managed a 5.65sec time (all G-Tech verified). For my eyes, that's pretty good on an N/A Roadster.
Title:
Post by: dieamond on July 5, 2005, 16:36
Yes the "bad" point with those mods is that they are so good that they have no downside, and you just don't notice them :p

When I switched to the shorter US gearbox with the COne flywheel, I didn't feel anything.

Then I tryed a stock MR and remembered what it was before  s:-D :-D s:-D

The only thing I really felt was the TRD LSD, very different (like in better) from the stock Torsen
Title: Re: Uprated Clutch and Lightweight Flywheel
Post by: Sam on July 5, 2005, 21:28
Hi Mark glad to hear the turbo is coming along!!  s:D :D s:D

Quote from: "markiii"4. Rev matching on the downshift now requires very little effort.

5. And the important bit, 1st and 2nd gear are now so much more fun, you really can feel the extra oomph.

Definetly agree on these 2, and you can't beat a dab on the accelerator in idle and hear her wind up quicker   s:twisted: :twisted: s:twisted:
Title:
Post by: aaronjb on July 5, 2005, 22:41
Me wants..  s:) :) s:)

Went for the RPS clutch in the 300ZX, mainly because the flywheel is rebuildable to take the carbon/carbon (good for 1000bhp, apparently) clutches.. But aside from that, they really are works of art  s:) :) s:)
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Post by: kanujunkie on July 5, 2005, 22:43
me too, i've already considered the clutch as mine slips slightly already  s:? :? s:?  

but if any bugger suggests a GB then my bank managers coming to get you!
Title:
Post by: Anonymous on July 6, 2005, 13:33
Quote from: "kanujunkie"but if any bugger suggests a GB then my bank managers coming to get you!

And my missus would be coming to get me  s:( :( s:(
Title: Re: Uprated Clutch and Lightweight Flywheel
Post by: Tem on July 6, 2005, 13:38
Quote from: "markiii"Surprisingly and Dan can back me up here (his is the same) for a performance clutch it's actually far far lighter than stock. I was expecting some really heavy noticeable difference. If anything it's a lighter change than stock, and the biting point caused no issues either.

Same goes for TRD. I remember wondering about it, cause everyone kept saying how performance clutches will require a lot of pedal force. Then again, seems all TRD products are something that could be a stock item and nothing too serious.
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Post by: Anonymous on July 6, 2005, 13:41
They sure are pretty
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Post by: BenF on July 6, 2005, 17:02
Got to give that same clutch and pressure plate the thumbs up as well - I got one installed at the same time as the PE turbo kit went on the car.

I didn't go for the lightweight flywheel - but with the RPS clutch grips well and is very nicely progressive for street driving, unlike puck or multiplates which can be a bit on/off sometimes.

To get away rapidly I can rec the PE turbo kit to around 4krpms and it will generate boost as I pull away - it will still light up the 225 rears if I've given it enough gas.

All in all, a good clutch, recommended ...