Best clutch for racing

El colonel · Post by **El colonel** » Mon Sep 25, 2017 11:59 am

I race a 1989 mk1b used for racing and I ride the clutch at the start for an average of 5 secs.
I have used Blue Print but they fall apart after 20 to 25 race starts so I'm looking for a clutch that will last longer. Any suggestions except don't ride the clutch cos it gains me places at the start.
Thanks

PW@Woodsport · Post by **PW@Woodsport** » Tue Sep 26, 2017 7:06 am

An 89 Mk2 you say.... this is the Mk1 section, I don't think an 89 Mk2 even exists!

To help you further can you clarify exactly what car you have?

SonicSW20 · Post by **SonicSW20** » Tue Sep 26, 2017 10:55 am

Dec 1989 SW20's do exist Paul!

El colonel · Post by **El colonel** » Tue Sep 26, 2017 11:02 am

Sorry guys its a typo I race a Mk1b
Looking forward to your advise

kaiowas · Post by **kaiowas** » Tue Sep 26, 2017 11:39 am

I've been sprinting my mk1 for years, mostly with a 4A-GZE (n/a clutch and gearbox type though so still relevant to you)

I fitted a brand new blueprint clutch in 2008 and it still had life in it when I replaced it after 7 years, 50 or so events and well over 500 sprint starts.

I turbo charged my engine at the start of the 2016 season (Currently putting out 260 odd HP) and at the same time fitted an Exedy Stage 2 Cerametallic paddle clutch have since done another 10+ sprint events (with at least 6-8 starts per event) with no clutch issues.

PW@Woodsport · Post by **PW@Woodsport** » Tue Sep 26, 2017 2:38 pm

Gazza_DJ wrote:Dec 1989 SW20's do exist Paul!

Well I've learnt something there, always thought they began in 90.

SonicSW20 · Post by **SonicSW20** » Tue Sep 26, 2017 2:53 pm

PW@Woodsport wrote:
Gazza_DJ wrote:Dec 1989 SW20's do exist Paul!

Well I've learnt something there, always thought they began in 90.

They might as well do really, December 1989 cars are very uncommon. I've seen just 1 in several years!

El colonel · Post by **El colonel** » Wed Sep 27, 2017 10:41 am

Wot about my clutch guys cos thats twice its broken up with me on start line?

jimi · Post by **jimi** » Fri Oct 06, 2017 3:10 am

Perhaps you need to rethink the way you start ?
Phil managed over 500 sprint starts out of a standard blueprint clutch with more power available than you have and still had life left in the clutch (he also suggests a possible uprated replacement)

kaiowas wrote:I've been sprinting my mk1 for years, mostly with a 4A-GZE (n/a clutch and gearbox type though so still relevant to you)

I fitted a brand new blueprint clutch in 2008 and it still had life in it when I replaced it after 7 years, 50 or so events and well over 500 sprint starts.

I turbo charged my engine at the start of the 2016 season (Currently putting out 260 odd HP) and at the same time fitted an Exedy Stage 2 Cerametallic paddle clutch have since done another 10+ sprint events (with at least 6-8 starts per event) with no clutch issues.

El colonel · Post by **El colonel** » Fri Oct 06, 2017 10:31 am

I start races by, once the red lights go on, i pull on the flyoff handbrake lift revs to say 5k slowly engage the clutch til its straining against the handbrake and revs fall back to say 4k then up to a max of 10 secs later (average 5secs) when lights out I'm off the line like a shot.
So all I want is the toughest clutch available to withstand the wear at the start for more than 20 races. I presume you guys are not holding at 4k revs with the handbrake for up to 10 secs and lihts out, but that gives me a really advantageous start.
Racing next weekend and need a new clutch NOW..

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kaiowas · Post by **kaiowas** » Fri Oct 06, 2017 10:31 am

To be fair a race start is probably different to a sprint start.

I don't need to worry about reaction times (timing only starts when I break the timing beam) so I don't need to hold the bite point for very long before launching whereas in a race start I'd imagine it's normal to hold the bite point at high rpm for several seconds waiting for the lights to change.

Also having more power works in my favour slightly, when I was sprinting the car as an n/a I would launch it from 6000 RPM on a warm day and it'd just go, if I tried that with the s/c or turbo I'd get nothing but wheelspin so I'm launching from much lower rpm these days.

Post by **Lauren** » Fri Oct 06, 2017 5:55 pm

What you are doing is burning the clutch out. I think given your launch style you just have to accept that you keep changing clutches frequently, or give it an easier time at the start. I would never hold the clutch slipping with the handbrake on.

When I used to race MK1s I always had trouble with wheelspin, but I don't slip the clutch. As it was a 20 minute race I had time even with a bad start (which happened most times) to make it up.

feral4mr2 · Post by **feral4mr2** » Sun Apr 01, 2018 1:47 am

I love using sprung center ceramic puk clutches with bigger clamp pressure plates.
If you use a reputable clutch builder they can change the fulcrum point of the fingers on the pressure plate and still have pedal feel of a stock oem clutch, saves building one leg bigger than the other like the old days of heavy duty clutches. haha

When they're new there's no slipping clutches with them, on or off. Plenty of stall practice.

They can be slipped a little ever so lightly as they're worn in, you'll here the chatter and know it's time to floor it and release the clutch at the same time. bang! engagement and go! haha

www.imoc.co.uk