I have been on my next performance quest for some time now. I have been reading all the clutch upgrades out there in the market place. Twin Carbon, single disk, dual disk, ect.....

It also seems that there are more and more threads posted about people breaking there drive lines after they have upgraded the clutch. The after market clutch are not the cause, but the holding power combined with some aggressive driving.

If I got a new clutch I would take it to the drag strip to improve my times or launch at a traffic light when someone wants to drag, or take it to the track and road race the hell out of it (road race would be the safest for the clutch). This mindset seems to be dropping some metal on the ground with a clutch upgrade. So why upgrade if you can't abuse it a little.

Again, from the threads I have been reading the last couple of months it seems to have a domino effect on the driveline if you upgrade the clutch. If the clutch does not slip then the diffs break or the gears bind and your EVO spits metal.

Am I wrong in my perception about this? What it the point of upgrading your clutch if you are putting a lot more jeapordy on more expensive parts?

I welcome your comments.

 

Excellent post, I've wondered this also.

 

me 2

 

Evolutionist, you have pretty much answered your own question about upgrading the clutch. Yes, it put's more stress on the driveline. Yes, you increase the risk of breaking other driveline parts. Keep in mind these are only machines, and as we all know machines will break/wear out at some point in time. Personally, my clutch went out at 6000 miles, then the transfer case was blown at 8300 miles. Do I have an upgraded clutch? Most definately. One thing to remember is that in an AWD car the transmission is usually the weak link (with a few exceptions). So take care of it, and it will take care of you. Or, do what the car was made to do, and beat it like a *****.

 

The EVO isn't built to be a drag car despite what anyone thinks here in the USA or despite how they drive it. It is a road course car. It has AWD for great handling and traction but that advantage is a two edged sword. If you abuse it; it will break. I have 12k miles on my stock clutch with a 3037S and standalone among other things. No breakage yet. I have the car apart to upgrade the internals and whatnot (nothing broke, just going to need them) so I am putting an HKS Twin in while I'm at it.
If you launch hard enough times, it will break. Very few AWD cars are tough enough to withstand that otherwise. If you don't want to break it, drive it like it is meant to be driven. I have no worries with 400+ whp on the stock trans as long as I am shifting smoothly and not hitting it hard in 1st, etc. Being smooth helps.
The upgraded clutch is there so it can hold the torque, not to improve my 60 foot times. I don't drag because it won't last forever that way. The EVO driveline is much stronger than most but it is still a machine; you run it hard enough, it will break eventually. Lightening the car will help.
I personally don't use full power in first and I rarely slip launch it.
Again, it isn't built to be a drag car. Mitsu, knowing some ppl would treat it like that, got it here to us (finally) but knew they needed a clutch that wasn't terribly strong; otherwise they would have to add $5k to the cost to cover warranty claims.
People in Europe are driving the same cars and getting 30k miles out of the clutch with most mods up to (but not including) an upgraded turbo.

Mark
www.Quantum-Racing.com

 

Thanks for the reply. If I am reading your reply correctly, the only point to upgrade is if you are going to road race the car or modify your car where the torque would over power your clutch's holding power. That would raise the question of, if you build it with a lot of Hp and Tq, but then could not use the full potential because of the drive line...what is the point. This is a catch 22.


I am trying to gather as many opinions in the matter as I can. I, as many people, are trying to figure out the formula for speed and handling with out jepordizing the car for daily use. I would rather replace a stock clutch than a stock drive line.

I welcome all opinions on the matter.

 

The upgraded clutch to replace the blown clutch is preparation for the upgraded transmission to replace the blown transmission!

 

Couldn't have said it better myself!!!!!

 

There are many guys out there with horrid amounts of power on the stock transmission and diffs. Drag racing puts a lot of load on the drivetrain. Road racing doesn't put as much. Accelerating away from a dead stop in first; the highest torque multiplication gear; really works the trans hard. Racing around a road course and using full power in 3rd and 4th in a smooth manner is not as bad. Being smooth is key to drivetrain longevity. Road racing requires you to be smooth to manage traction. While you can do your best in drag racing, there isn't anything smooth about covering sixty feet in less than two seconds from a dead stop.
If you are running your car like a road course car, you WILL need a clutch to hold "big turbo" power. It won't kill it in short order, however, if you can drive well and it won't destory the trans necessarily either.

if you build it with a lot of Hp and Tq, but then could not use the full potential because of the drive line...what is the point

My point is that the full potential of the car is not drag racing and therefore you can use the potential of the car as it was intended. That is NOT to say you can't make a wicked street drag machine out of them. Quarter times are one of many great ways to get a rough estimation of the performance of a car or a modification as well.

Mark
www.Quantum-Racing.com

 

Can anyone say Exedy Carbon Twin-Disk?

 

I'm looking at this clutch right now... but not for drag racing, but longevity... problem now is I've seen more than a few trashed OE throw out bearings... makes me wonder if a high end clutch is worth it if I got to tear it down within a year to replace the bearing anyway.

 

The launch has a lot to do with the EVO's awesome performance. In a good AWD drivetrain the clutch is the first part to give. This is to save money replacing the drivetrain. A stonger clutch will allow a racer to do more drag racing launches. If you do not launch this upgrade is not needed as much.

Example.

a 1/4 with no launch is arond 14-14.5 seconds.

a 1/4 with a good 5-7 k RPM lauch will give you around 13.8-13.08 seconds.

The launch makes up for the turbo lag and lack of botton end power.

When you rev past 3500 RPM you are allowing your turbo to spool up. The end result is turbo from the start to the finish of the 1/4 mile.

The Evo is AWD which gives this particular car a huge advantage off the line and in the majority of the race. Whie the powerfull RWD car is trying to send it's power to it's wheels the EVO is gone.

Hope this helps.

 

Guys,

I still can't believe that there are people who are so naive to believe that 80+ percent of the purchasers of EVO's in the states don't run their cars in a drag racing format a lot of the time. I don't mean they are going to the strip every weekend or they are maximum launching at every stoplight, but the majority of Americans like straightline speed and accept the great handling as an added plus. In other countries where their road systems don't lend to drag racing activities, ie. two lane twisty roads, the handling is more appreciated.

IF you go to a dual plate Exedy and your horsepower is less than 400, your drivetrain will not be in any more danger of braking than normal. The EVO really has a strong transmission and differential setup until you get over 400hp. Obviously, stupidity cannot be counted out under any kind of usage. The EVO is a performance car and should take reasonable performance driving, yes, even drag racing.

 

Thanks for your reply. I am curious, what do you base your information about the twin plate on. The slippage when engaged, or is there some very detailed info out there I can find.

 

I am basing the info on the fact that there have been many posts on clutch problems and the solution has been the Exedy or something similar but there have only been two front differentials posted and both of those cases the individuals were running 500+ horsepower. Considering that almost everyone does at least a few full load launches in the first few thousand miles of driving the EVO, that speaks very well for the strength of their drivetrain. Don't get me wrong, I don't think the EVO should be taken to the strip every weekend and survive 10 lauches each night with a 400+hp car. You will get wear and tear and the occasional oops with missed shifts and that can bust up a lot of things, But for an occasional street light mine.s bigger than yours and a trip to the strip every month or two, you should see plenty of use out of the drivetrain (clutch excluded of course)