] I just received my new 6 speed convertable. Three questions, the clutch pedel has a spring which lowers the effort as you depress it to the floor. When you let it out and just before it grabs the spring pressure increases making it difficult to control. Is the mechanism adjustable for either height of engagement or spring pressure?

Second, the exhaust is so quiet you can't hear motor in traffic at a light, so you aren't sure how much gas (RPM) you have when you let out the clutch, unless you look, which blows. So where do I get a Corsa system? are they factory installed? my dealer said $2000 and they would do it!

Third, Is the throttle by wire adjustable, for reaction time, it's slow. When you blip the throttle on down-shifting, nothing much happens, not too cool when I keep missing the required RPM and lurch the whole car.

No, this is not my first manual Corvette, and I am an engineer by background. Any thoughts would be appreciated. I wish now it had and automatic. And yes this is my first post.

Thanks, John B

Ps. I can post a picture if someone tells me how.

 

Hey, save your money. $2000 for corsas. Instead, Buy a set of kooks headers,high flow cats $1600 and $350 for the install, and get some HP! for your money, not just some sound. Think about Magnaflows I have them with the kooks system. I love them. With tunning 386RWHP/377RWTQ. you won't be sorry.

Andy G.

 

I too am havong a hard time matching revs on downshifts. The throttle response without a load seems very slow, it may be by design but would love to hear others experience.

 

Andy, Can you hear the exhaust when retaining the stock mufflers? Is yours auto or std. What did your installation cost?
I agree fastguy. If I tap the pedal nothing happens?

Anybody else?

 

Dunno, mine bilps and gives good rpms for downshift/turn. Gotta learn not blip so hard though. I'll be going to Spring Mountain in Sept and will report back then.

 

Forget the clutch. After 700-1000mi it gets much easier.

 

The throttle response is definitely much slower than on my C5 - I may get used to it, but I sure don't like it now. I wish someone would tell us how to make it more responsive.

 

I don't have my C6 yet, so it is hard for me to comment specifically about the problem. But, it is an old hot rodder trick to reduce the air gap between the clutch friction plate and the flywheel. This is a trick out of the 1960's that probably few people today are aware of. What does this mean? It means that there is free play between the point when the clutch is completely depressed to the floor to the point when the clutch engages as you release the clutch pedal. If you reduce that free play (also called "clutch throw") you can get a smoother start, this is true not only on the drag strip but also in normal driving on the street. Drag racers want a short throw to improve their time off the line, but a short throw also makes street driving and clutch engagement smoother and more comfortable.
Some cars (BMW) have an adjustable clutch stop beneath the clutch pedal, i.e. just a rubber piece that can be screwed in and out to adjust the clutch throw. Some people actually weld an adjustable screw and plate to the clutch pedal to adjust the throw, a bit excessive. I may be wrong but I don't think Corvettes have a clutch throw adjustment, many cars don't.
I have a very simple solution that I have used on practically every stick shift car I have ever owned. I use some pieces of thin indoor/outdoor carpet - you can also use a thin piece of plywood - that I place beneath the OEM carpet where the clutch pedal hits when it is fully depressed. By building up the height of the carpet at the point where the clutch pedal hits, you lessen clutch throw (also reduce the air gap). By trial and error I keep adding pieces underneath the OEM carpet until I get the kind of clutch action I desire, i.e. short clutch throw before engagement. It is kind of a clumsy fix but it is woth a try.
Because cars today have a clutch cutout switch there is a limit to how much you can eliminate in clutch throw, i.e. if you buildup too much, the clutch does not depress enough to activate the switch and the starter will not engage. But generally there is at least 1/2" or more of free play that can be eliminated. It doesn't sound like much but it does enable much smoother clutch action. It is a simple trick that is easy to try. If it works, that is great, if it doesn't work, forget I ever told you.
I am kind of interested in how many on this forum have ever heard of the trick. I may be one of the few old rodders still active that have done this. I have only seen this described once on the Internet, it was on a forum for Ford Mustang drag racers.

 

I drove a C6 MN6 extensively right off the dealer's lot (brand new), and had no problems with the clutch or matching the revs on the downshifts.

The transition from the C5 was simple.

Try driving it for a while and practice.

 

I don't think the clutch can be adjusted, it's hydrulic. Not positive, but that's what I'ver herd. It gets easier over time and practice.

Secondly, there is no throttle cable on the accelerator pedal. It's a drive by wire system.

Good luck getting "used" to your car. My recommendation is for lots of practice.

 

Thanks for the replies. I have a Q 45 and the throttle by wire had several program adjustments for responsiveness, I wonder if GM has something similar. On an auto car it would not be as much of a concern.

 

I've only had the opportunity to take a short test drive in the C6. My car will be built on the 18th. I'll be there to witness the birth. I do remember however that there seemed to be a very small amount of accelerator pedal movement before the throttle started to respond. Almost as if there was slack in the throttle cable that needed to be adjusted out, although I know there is no cable. I wonder if there is a way to improvise and reduce the travel of the pedal to take out this dead spot before the throttle responds. Without having a car to experiment with this is a little tough for me to try. In a few weeks I plan to check it out on my car. Anybody have the same take on this?

 

My system install cost $250 for the headers, and cats. The magnaflows were free for letting them use my car for R&D. I would guess another $50-100 for the cat back system. The headers would give more sound even with the stock mufflers. Some have done that and like it.

Andy G.

 

I am kind of interested in how many on this forum have ever heard of the trick. I may be one of the few old rodders still active that have done this. I have only seen this described once on the Internet, it was on a forum for Ford Mustang drag racers.

I've heard of it but not done it. My manual cars had mechanical clutches that were adjustable at the 'Z' bar and accomplished the same thing.

 

aaaaa

This was an earlier thread on clutch problems. There is a more recent thread with more info.

 

There is no adjustment, per se.

My clutch mod helps, though, and can be seen on my forum picture page:

http://forums.corvetteforum.com/phot...00/ppuser/6747

It's some sort of clamp I found in my shop, that I attached to the nubbin up on the clutch pedal arm. I really helps clutching. There's a shorter throw, and the clutch engages earlier, and more predictably.

You can post your own pictures by signing up here:

http://forums.corvetteforum.com/photopost/index.php

 

If you're talking about the carpet trick, it won't work on our C6. Get under your steering wheel and have a look. The clutch pedal and arm geometry is wrong.
Then check out my clutch mod, if you're interested:

http://forums.corvetteforum.com/phot...00/ppuser/6747