View Poll Results: After doing the drill mod, did you notice a difference in your high/any RPM shifting?
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Drill Mod Poll
#22
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Hmmm, results are starting to show that most people notice some kind of difference after the mod, even if not a huge one. Knowing that it's a cheap mod that should for no reason CAUSE problems but may fix them if you are having issues, I can't see not doing it. I'll post my results this weekend after I get it done Friday. Keep them coming, guys!
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I did not do the drill mod to the master cylinder. M6, heads, cam, intake, stock 3.42 gears, and I have trouble accelerating at over 2500 rpms while trying to shift. Does it for nearly every gear shift.
How long does this drill mod take to do? Should it be drilled 1/8" or even narrower, like 1/10"?
How long does this drill mod take to do? Should it be drilled 1/8" or even narrower, like 1/10"?
#26
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I guess it's not the most difficult job if you know what you're doing, but I was told it's time consuming. My car is going into the shop tomorrow for a tune anyways, so I'm just paying them to do it so I don't have to deal with it.
Search for "drill mod" on here and you should get plenty of info on it. I know there is a detailed install article on installuniversity.com.
Search for "drill mod" on here and you should get plenty of info on it. I know there is a detailed install article on installuniversity.com.
#27
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My problem is at high rpm (6000rpm) shifts. I will hit the clutch pedal to shift try to grab a gear and it wont engage. Right after that happens the clutch pedal stays down on the floor. I pull it up, pump it a few times and everything is back to normal. I just did the drill mod and flushed the fluid last week and it made no change in the problem I have been having. I was going to replace the slave cylinder and clutch while I was there, but maybe I will start with a new master cylinder.
#28
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Originally Posted by muddyjimmy
My problem is at high rpm (6000rpm) shifts. I will hit the clutch pedal to shift try to grab a gear and it wont engage. Right after that happens the clutch pedal stays down on the floor. I pull it up, pump it a few times and everything is back to normal. I just did the drill mod and flushed the fluid last week and it made no change in the problem I have been having. I was going to replace the slave cylinder and clutch while I was there, but maybe I will start with a new master cylinder.
thats what mine does, i did the drill mod and it helped alittle but i think the only for sure fix is a new clutch /pp/flywheel
#30
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Originally Posted by muddyjimmy
My problem is at high rpm (6000rpm) shifts. I will hit the clutch pedal to shift try to grab a gear and it wont engage. Right after that happens the clutch pedal stays down on the floor. I pull it up, pump it a few times and everything is back to normal. I just did the drill mod and flushed the fluid last week and it made no change in the problem I have been having. I was going to replace the slave cylinder and clutch while I was there, but maybe I will start with a new master cylinder.
#31
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Where can I find instructions on how to do the mod? I tried a search but I just find post of people speaking of it. Not really seeing instructions. I have my clutch out now and ended up having to order a new flywheel so I have a day or so to wait till its back together.
#32
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http://www.installuniversity.com/install_university/
check under the Install Documents > Transmission
There will be some differences because you are a C5 but there's enough photos and info to get you everything you need with one exception; I highly recommend a GM clutch line removal tool. They are $5 and make a hard job simple when it comes to dis-engaging the clutch hydraulic line from the slave cylinder in the bell housing.
check under the Install Documents > Transmission
There will be some differences because you are a C5 but there's enough photos and info to get you everything you need with one exception; I highly recommend a GM clutch line removal tool. They are $5 and make a hard job simple when it comes to dis-engaging the clutch hydraulic line from the slave cylinder in the bell housing.
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So this restriction could possibly be my problem with high rpm shifts from 4th to 5th gear? After 4th at high rpms I can't grab 5th or 6th untill I get off the gas. (Stock clutch setup)
#37
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I think I just waxed my 4rth gear syncro's because of this. 1-2,2-3 shifts were ok and I could not for the life of me get the car into 4rth gear unless I paused for 1 second and then pulled it in. I need to get this right cause it isn't easy to yank the driveline in this car.
#39
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i did the drill mod when i swapped stock clutch for the ls7 setup, old clutch wasnt too bad, my fluid was black as heck, slave was glazed so i replaced that also, now i have no issues, shifting is a breeze now, high rpms, launching, everything is smooth