joelamite

iTrader: (1)

Anyone out there using a button clutch on a genIII lq4 engine?

I'm currently in the planning stages for setting up the driveline on my racecar. (road race)

I had a genI 383 with a 7.25 button on an A/T Flexplate (stock starter location) and a 3 disc clutch pack in the car.
Now converting it to LQ4

Called QM, they make a button for the LS1 so that should be all I need to buy as far as clutch components are concerned..???
I plan on running a A/T lq4 flex plate for the stock starter.

? what pilot bushing do I use?
This setup will be on a lq4 crank.
What bolts?

I have my old t-10 style 4 speed I plan on using as well with the old hyd t/o bearing.

Do I continue to use the crank spacer on the lq4 crank?

Thanks in advance.

GIGAPUNK

iTrader: (2)

You might find this thread helpful

https://ls1tech.com/forums/manual-tr...er-master.html

I plan on going the same route, but I'm still a ways out.

joelamite

iTrader: (1)

Thanks, I read the entire thead, lots of opinions and not many had any real experience with them...
After having/driving that clutch on the back of my piev. motor, I do not believe that guy driving it on the street like he claims. Yes I imagine you could steet drive it but it would SUCK.
My experience with the little clutches, no stored inertia, incrediable throttle response/rev, on off switch, and when you take off from a start you have 2 choices...
Spin the tires or stall. You slip the clutch you will be buying new discs...
Its not just the fact that the weight is lower but that the weight is located tight on the centeline of rotation lowering the MOI. Sure it revs up quick but even my built 383 felt like it had 25 hp from a start.
I describe driving those clutches as take your stock equiped clutch car and let your foot slide off the side of the clutch pedal. that is how hard this clutch grabs. Try only ever doing that in traffic.
I would only ever put one of these on a racecar.
I'm not sure I even want one on mine again as you can't even put the car in the trailer with it.
I was driving my friends craftsman truck at VIR a few years back, he had a 5.5 in his.
We let one of our crew guys drive it up to the gas pumps, the next time I went out it did not have any clutch left.

They are also noisy. I can hear the clutch over open exhaust.
I can hear others with this setup on track as well...

GIGAPUNK

iTrader: (2)

The pure carbon clutches solve most of those problems. They can be slipped, and last forever. The only car I know of that comes with one is the Porsche GT supercar. The porsche uses a triple plate pure carbon button clutch very similar to the $6000 clutch that LG sells. There is usually such a clutch available on ebay. They were used in the 1999-2000 LS1 powered ASA race cars and can usually be had for around $2500 including reverse starter bellhousing.

I'm still very curious about Specs mini twin. Available in organic and under $1500.

You could also go 7.5" dual or tripple and pic up some more thermal mass. Granted it doubles the MOI every time you increase diamter by about 2", but maybe that's a good thing! Going up to the stock diamter from 5.5"" with the same weight increase the MOI by 2^4 = 16 times!!! Then take into acount that one of these clutch/flywheel combos can get under 15 lbs from the stock 52 lbs, and wholly crap! That gets you an increase in polar moment of inertia of over 55 times!!! There's a reason you can feel that. Can you imagine how fast a n engine would rev if you could reduce the weight of your rotating assembly to 1/55th of it's original weight?! I don't think that this will behave any differently.

You can also increase thermal mass with extra plates. And I'm pretty sure tilton makes anti-rattle straps now, but most race car guys never use them of course.

Tilton
http://cgi.ebay.com/ebaymotors/Tilto...item1e477dd633

Quarter Master
http://cgi.ebay.com/ebaymotors/Quart...item1e477dd64b

joelamite

iTrader: (1)

COOL!!!!
That is what I need!!! Sounds like it solves the hateful problems of the small clutch while retaining the benefits.
You helped me find that now if only you could help me find an extra 2g without the wife knowing???

I think I am going to go with the LS1 QM button and use my existing (and hateful) 3 disc 7.25 setup from the old motor as I do not have any more $$$ to spend this season on parts. I have 3 discs with 2 weekends on em and a new box of discs in the trailer.
Hopefully my bell housing will take a big flex plate... I will measure tomorow.

I've got some pats in the garage, maybe they will end up on ebay soon to get the above setup.

Anyone need an AED HP Holley Carb? comes with road race floats installed, with a set of drag floats included.

GIGAPUNK

iTrader: (2)

See if they'll take the new discs back in exchange for organic ones. The organics will likely be a little thicker, but I'm sure you can figure out a way around that.