PewterScreaminMach

iTrader: (7)

Hi guys,

If this poll was done before, I couldn't find it and I'm curious to see one, so here it is.

If you have done the drill mod, did you a) absolutely notice a difference, b) possibly notice a difference, or c) not notice a difference at all in your high RPM (or any RPM) shifting?

Comments, suggestions, etc, are all welcome!

brad8266

iTrader: (23)

Mine would grind going into second when under hard acceleration/high rpm's, drill mod fixed that.

Screamin_Z

iTrader: (2)

I voted the middle one because I haven't raced yet with the nitrous to see if it really did help. plus when I did it I put in a new clutch.

shoemike

iTrader: (25)

you will notice a difference in clutch re-en engagement (it will release faster) but if you are grinding and have trouble getting into gear
you should look into a mcleod master cylinder.
it fixed my issues in that regard where the drill mod alone did not.
and if i had to do it over i would have drilled the line less than 1/8".
here is a link to a smokin` deal on a used one.

https://ls1tech.com/forums/lsx-parts-sale/775898-mcleod-adjustable-master.html

if grinding and gear engagement is your problem the drill mod alone may or may not be the best choice depending on your mods
and what issues you may or may not be having with shifting.

cws T/A

iTrader: (3)

Before the clutch peddle stayed stuck to the floor speed shifting , after it barked the tires through 2-4 gears .

PewterScreaminMach

iTrader: (7)

Thanks for the posts. The results look pretty even at this point. Keep them coming!

Yeah, I have major troubles shifting (it's like it hits a wall between gears and causes me to miss shifts a LOT), but have replaced the clutch twice, replaced the slave cylinder, bled the clutch twice since the new one (two different ways), and rebuilt the tranny (after I lost the fourth gear synchros). I am still having the problem, so when I take it to get it tuned next week, I want to get the drill mod done and possibly replace the master. I was thinking about just getting the drill mod done and seeing if it helps, then if it doesn't, doing the master so I don't waste the money if it does.

JasonShort

iTrader: (242)

I voted in the middle. I was experiencing tough shifting at high rpms and my pedal would loose all pressure after two shifts. I rebuilt my clutch master cylinder, made it adjustable, did the drill mod, new fluid, and bled it real good. It helped a little, but not as much as I would have hoped for. The pedal will still go soft after a couple high rpm shifts...though not as bad as before.

Jason

bayer-z28

iTrader: (14)

I noticed a little bit... Not a HUGE improvement.. Just a little better response time..

Formyla

Bad traffic and high heat toasted my master cylinder (02 Z28 42,000 miles)
I bled and flushed - mity vac'd - gravity but alas the MC was toast.
I was lucky enough tho cause when it finally completly bit the dust I was in front of Thunder Racing
Shane installed a mcleod master cylinder, 1/8 drill mod, and insulated the line for me that morning before the shop opened.
I voted center cause I believe the best improvement was from the mcleod master.
Shifting is always consistant now tho I think the trans it self could use some work to smooth the internal movement.

MrEddie

I could hit second without losing many rpms (slight chirp), but then third was locked out when shifting at redline. The drill-mod has solved that issue.

myfast70

iTrader: (38)

I just replaced all of my hydraulics with my clutch change and haven't had an issue yet without the mod! The biggest difference that I've noticed has been changing my clutch fluid usually after every 1-2 nights out. When looking at it you wouldn't think that there is anything wrong. But put it in a clear plastice bottle and some new fluid in another and you'd be surprised how dark it is when you compare the two. A buddy of mine that suggested it said it worked great for him, so I thougt I'd try it. I know this probably would be feasable for most people that DD their cars.

PewterScreaminMach

iTrader: (7)

Well so far it seems like the majority of people who do this notice some sort of difference, but it sounds like replacing the master cylinder and possibly replacing all the hydraulic lines should definitely be my next move after the drill mod. If I'm still having troubles after that, the only thing left would be to go with a brand new tranny instead of my rebuilt one. The issue was there before the rebuild, so it makes me wonder if something that wasn't replaced in the tranny is causing the problem.

01Z28M6

I think you have it right.

I drilled the restriction out with a 7/64 drill. The pedal used to feel like it was a cold day and the fluid was thick. That doesn't happen now but I did miss 3rd gear at the track this week as was eliminated in the first round. I'm blaming it on the hydraulics.

The fluid was jet black when I did the drill modification. This tells me the rubber is breaking down and probably won't quit just because I flushed the system. I haven't inspected the fluid since the mod but by just looking at the translucent master it appears to be darkening.

2QUIK4U

iTrader: (7)

I did the drill mod to my old master cylinder and I could tell a slight difference but it made more of a difference when I replaced the master cylinder with a new GM one. I had the Mcleod at one time also and it worked well but Im using a Textralia clutch and they only recomend GM hydraulics.

shoemike

iTrader: (25)

just don`t bother with a stock master for replacement.
it will cost you more but an adjustable is worth it.
the mcleod has a bigger piston than stock.
your problem is most likely that your master is not pushing enough fluid.
i thought i needed a new clutch (30,000 miles)
after i installed the mcleod it was all good.
i can`t guarantee it will fix what ails you but it is worth a try,
especially if you want to save some money over buying a new gear box
and still possibly having not solve the problem.
if the the problem was there before your rebuild ,
maybe you didn`t need a rebuild?

PewterScreaminMach

iTrader: (7)

The rebuild happened because I destroyed my 4th gear synchro and locked it in fourth.

I am hearing more recommendations to go with the stock GM master rather than an adjustable one, and from a lot of reliable sources, so I'm going to try that this Friday when I get the car tuned and the drill mod done. I'll let everyone know how it goes this coming weekend.

shoemike

iTrader: (25)

oh.
but truthfully i don`t see why a stock master will help you but it`s your choice.
unless it is leaking there is probably nothing to gain by replacing it
with another stock piece.
good luck and have fun

PewterScreaminMach

iTrader: (7)

I didn't have an issue with the pedal sticking after WOT runs until after this most recent clutch was installed, so we think the master cylinder might be biting the dust. Even after bleeding the clutch twice with two different methods, the pedal stopped coming up all the way on its own while bleeding it. I'm hoping that between the new master and the drill mod, my problems will be taken care of, but we'll see. If they don't help, I'll start looking for more things to fix .

transam45

iTrader: (2)

im looking at doing a swaping my a4 for a m6 should i go ahead and get the after market master to start off with or see how the stocker does first ?

bad6as

iTrader: (17)

i did the drill mod when i did the clutch and when i had the trans rebuilt so i didnt notice a night and day differance but so far i have not had any clutch or trans issues