is it possible to do the drill mod without removing the transmission?

i have searched and not found any helpful results.

anybody have any advice on doing this mod?

 

Yes, you can just remove the master cylinder assembly.

 

while looking at the line going into the transmission, it doesnt seem to have a hex head or anything that can be used to remove it from the bellhousing. does it just pull out, like a grommet-type deal, or is there another way to get to it? and the restriction is at the end going into the transmission, correct?

i guess it would just as well be worth it to do an adj. master cylinder with this rather than just take it out, drill it, and put it back in? there are no problems with the current one (except needing to do drill mod)

thanks for your help, any more would be greatly appreciated.


and why this was moved, i have no idea. it was originally posted in general fbody........

 

Having watched a buddy of mine make the mod on his 99 SS a few years ago, the restriction is at the top of the system, where the line connects to the master cylinder - hence, Spinner's response. The line is held to the MC by a roll pin. When the line goes into the bellhousing, it continues to the slave cylinder, which is concentric with the tranny input shaft - but you dont' need to touch that, except to bleed the system after you are done. There is a big hex shaped bleeder tube that extends from the slave cylinder to the opening in the bellhousing, but its hard to see. You will also have to bench bleed the MC before you reassemble the system.

It was moved because a clutch is part of the "Drivetrain".

If you have any concerns about the actions of the Moderators, please use a PM.... do not raise concerns in the thread.

 

I did it last year.

Your hydraulic line must be disconnected using a $5 tool that is a simple flat fork that slips over the end fitting at the bell housing. Any auto parts store should have them. I bought one for a ford that fit a little too tight but still worked.

You don't have to remove the transmission for sure. I removed the master cylinder with line attached. You can feed it up and around the vacuum boost with a little patience and put it back the same way. The hardest part is to re-install the master cylinder U clamp as you "almost" need to be on the outside and inside of the car at the same time.

Once out of the car the line can be removed by driving the 1/8" roll pin from the connection. When drilling the restriction in the line end fitting, realize you are only drilling a tiny distance.

If you go here: http://www.installuniversity.com/ins...sity/index.htm

Select LSX Vehicles
Install Documents (list on left side of screen)
Scroll down to Transmissions

You will see the mod for the McLeod Master Cylinder.

I have tried to find the link that I used to do mine but things have changed and that page is apparently no longer available in the same place. You see some Camaro related topics but the drill mod info is gone. I'm going to take the liberty of re-posting what was once there, giving credit to the author. If there's a problem with that then I'll ask the moderator to please remove this post or edit it so the following text is removed.

================================================== =======
Drill Mod
Deogey, 26 November 2002

This modification is for M6 cars. It seems that GM has put restrictors in the master cylinder hydraulic lines so that non-enthusiasts would be able to drive the car without the clutch engaging too fast and causing the car to lurch forward. With the restriction in place, it slows the clutch so much that you can easily burn the clutch while shifting hard, common on the 2nd to 3rd shift. Unfortunately if you're going for performance you want the clutch to engage quickly! This mod removes that restriction completely, allowing your clutch to function to it's full potential.


1. Undo the line from the slave by sliding the nylon ring in toward the
slave and remove any necessary heat shields to free up the line.

2. Remove the under-dash to gain access to the clutch inside the car.

3. Unbolt the U-bolt nuts inside the car as well as the clip at the end
of the rod to the clutch pedal.

4. Remove the U-bolt. This is a little tricky to do because of the clip
thats on it to the inside...if you can get to it and remove it great
otherwise start tht nuts onto the bolt and beat it to
submission...errr... i mean until it comes out. Take the retaining clip
and throw it as far as you can, as you will never use or want to see it
again.

5. Fiddle with the assembly to get it out of the car. Takes some time
but it will come out, i think i fed mine out under the brake booster on
the engine side.

6. Push out the roll pin and remove the line.

7. Insert the drill bit of your choice - the magazines say that 1/8 will
fit but this WILL drill some of the fitting also, I used 7/64 which
slides past the fitting to the restrictor. It's good to have an idea
where the restrictor is in the line before you go nuts with the drill.
It should be about an inch in just past the compression sleeve for the
fitting. The restrictor is about 1/4 inch long and very soft so it
doesn't take much to drill it out use slow speeds to reduce the amount of
metal shavings.

8. Re-install the modified line.

** an assistant is very helpful from here on **

9. Connect the old slave from above and put the slave in a vice so it
won't over extend. Bench bleed and Flush out any metal that is left in
the line. I bled mine until the fluid that came out was clean and metal
free... about 3-4 M/C cups full.

10. Re-install the M/C. Very helpful to have someone else to assist you
here, took me about 1.5-2 hours alone just to re-install and put the car
back together.

Drill Mod FAQ:

Q: Where is the slave cylinder located?
A: If you are facing the engine bay it's just down and right of the brake booster, it's actually in the tranny, well, between the clutch pressure plate and the tranny actually.

Q: Step 1 mentions removing the line going to the slave cylinder, but I see a few lines. Which is which?
A: On the outside of the bell housing you'll see 2 things sticking out. The top line is a bleeder, and the bottom is the line you want to disconnect. The line comes apart by pushing the plastic sleeve back and it will release it.

Q: Where is the master cylinder located?
A: Up on the firewall, it looks like a small brake reservoir. Know where you put brake fluid in? If you're standing over the driver's fender and you look a little closer to you you'll see another reservoir there for the master cylinder, it's lower and closer to the outside. It has a line that runs down behind some heat shields to the tranny/bell housing/slave cylinder.

Q: On step 2 you mention removing the "Under-dash." What is that?
A: The plastic that is under the dash and above the pedals. (The root of all evil.)

Q: How is the master cylinder attached to the firewall?
A: The clutch mc is held in by a U-shaped bolt. 1 bolt thru both holes, like on a rearend.

Q: How does one do a bench-bleed?
A: After you drill the line you have to flush it out to get all the metal out of it. You could use a hose, but I never liked the idea of mixing oil and water, plus brake fluid is dirt cheap. So, to do the bench bleed you'll need to support the reservoir above the master cylinder and let the line hang lower than both. At the end of the line there's a little "check ball" inside that you will need to jam open with a nail or something. Fill the reservoir and push on the mc rod until it pukes out clean fluid from the line.

Q: Do I need to worry about getting air in the system?
A: Not if you bleed it before you reconnect to the slave.

Thank you Deogey for submitting this!

 

Does this mod apply to an LT1 also or just an LS1? camaro409

 

From all I've read, the restriction in the slave line is unique to the LS1. I have not heard of the restriction issue with LT1 cars.

 

LS1 only.