1.6 or 1.8 clutch ?

[Fatty]

ok i'm asking lots and lots of questions today

my car will never ever see more than 150kw at the rear wheels. i've decided to set myself a limit and build to it.

soon i will need to upgrade my standard na6 clutch. since the turbo has gone on, it is handling about 100 rwkw at the moment and doing ok. but i will be increasing the power soon.

i have a 1.8 flywheel sitting here. so i need to decide if i use it or not. i am told that mania have got cars running aftermarket na6 clutches with about 200 rwkw. i am most interested in the difference between responsiveness ( i hope this is the right word) between the 1.6 or 1.8 flywheel. in other words, the way the car revs. i beleive an engine fitted with a 1.8 flywheel does not rev as freely. i am not sure if this is a positive, or a negative, given that my current experience is that the turbo tends to make the engine rev out very quickly with the 1.6 fly. i'm kinda thinking that the heavier flywheel might actually smooth things out a bit .... ?
also interested in cost differences between a na6 and na8 clutch , with the condition that they both can handle similar power. ie - will it be cheaper to fit a mid quality na8, rather than a top quality na6.

ok wth all that rambling, hopefully i've set things up for you, as to what my thoughts are. now tell me what to do

[fastfreddygassit]

Just my own observations Fatty..
The 1.6's I have dríven have seemed much \"sweeter\" to rev than the 1.8's I have dríven
including my own. Fitting the cams and extractors and new intake has improved
the feel/sound of my car revving but it still doesn't feel as \"sweet\".
I put it down to differences in flywheel weight and inertia due to the smaller diameter of
the 1.6 flywheel. I have purchased a 4.5kg Toda CrMo flywheel that I will fit as soon
as the new exedy clutch kit comes in, which will hopefully be this week. I am hoping that
with this set-up I will have the \"sweet\" revving that the 1.6's have.
Then I'll let you know if everything is \"sweet\"

[Boags]

I feel like dessert after that, thanks FFG...

1.6 FTW. If you can handle the stiffer pedal feel, stick with it, unless you want to pay ooodles for a lighter 1.8 sized flywheel.

Boags

[4sfed5]

if your turbo then get a 1800 flywheel and H/D clutch package...my 1800 750kg pressure plate is barely handling 150RWKW i cant see a 1600 clutch handling it...get a fidanza/ACT happy meal from flyin miata to be sure......
If you use your car not very often then this is even more important..a daily dríven car will kepp its flywheel clean of rust and crap..but a car thats dríven only on weekeds or once a month will build up rust on the fly wheel just like a disc brake and when you put your foot in it, it will slip on the deposit dust and turn your clutch to a useless piece of crap...ASK ME HOW I KNOW THIS....

A CLUTCH THATS 90% OK IS STILL A USELESS (EXPENSIVE)CLUTCH!!!!!!!!!!!!

[bigdog]

My SP is running 147rwkw through a stock SE clutch (replaced under warranty by previous owner at 50000km to address clutch shudder problem). It now has 120000km on the clock and the clutch is fine. But... I don't work it hard off the line - always wait till the car is moving and clutch engaged fully before planting the boot. One of the biggest issues with turbo cars and clutches is the boost curve - a steep or sudden increase in boost will defeat all but the best racing clutches - Dave's car is a good example of this, and he now has a much stronger left leg to prove it, yet at the time his was slipping we were making very similar power on the dyno, the difference was in how quickly his came on boost - and of course this relates to better acceleration times at the track.

Fatty, I doubt you would notice much difference in your car between 1.6 and 1.8 revability because of the turbo - you would benefit more from the 1.8 flywheel mass I think as from memory this helps with turbo spool up lag - ie if you have a light flywheel the engine revs drop very quickly on closed throttle - meaning more 'lag' in spooling the turbo up again when you open the throttle (not that our cars suffer any noticeable lag though).

The whole point of light flywheels is for throttle response in a normally aspirated engine, and adding horsepower due to reduced reciprocating mass - neither of which affect a good turbo engine. That's my take on the matter based on what I have read anyway...

[Fatty]

this is great info guys, thanks for taking the time to share your thoughts.

hmm, i'll have to do some thinking on this one ....

[fastfreddygassit]

this is great info guys, thanks for taking the time to share your thoughts.

hmm, i'll have to do some thinking on this one ....

give me a ring, or rock on up to a Thursday night, and we'll organise a time for you to take my car
for a thrash so you can assess a lightened NA8 flywheel combo vs yours.

[Fatty]

thanks fastfreddy. that would be cool. i MIGHT even let you drive my car too

[fastfreddygassit]

thanks fastfreddy. that would be cool. i MIGHT even let you drive my car too

*Cue the Jeremy Clarkson voice over*
POWAAAAAAAR