This winter I planned to do all the brakes on my Opel Gt. I was thinking of upgrading to the new 9" booster that Opel GT Source was advertising. I just got their Christmas flyer specials in my email this morning and they were offering the booster plus the new master cylinder for $199 and a complete set of calipers and pads for $199 until the end of the month. I called them up and Dennis claims that they tested the new set up and it actually stops better than the big brake set up they offer. While I'm at it I'll install my new rotors that I already have and a set of brakes on the rear. Next spring I'll let everyone know the verdict. Maybe some one has already tried the new booster.
Last edited by hrcollinsjr; 12-19-2011 at 09:08 PM.
I just got their (OGTS) Christmas flyer... I called them up and Dennis claims that they tested the new set up and it actually stops better than the big brake set up they offer. booster.
Wow,...you must have spoken to Gil or Dan today, as I no longer work at OGTS. It's either that or I have a secret double?!?!
Dennis
Last edited by hrcollinsjr; 12-20-2011 at 09:46 AM.
Drifting: dorifuto sōkō, a motor sport where the driver intentionally oversteers, causing loss of traction in the rear wheels through turns, while preserving vehicle control.
I didn't get the new 9" booster but did install a slightly smaller one out of a Kadett. It made a big difference. I suspect the 9" would be even better.
You no longer work there?? After years of speaking with you over the phone, I'm sure I speak for several others here, that you will be missed.
Merry Christmas!
Yes, after just over 13 years working at OGTS, I have moved on to be with the love of my life. Does not mean I'm out of Opels however. My wife knows all about my obsession from High School.
Drifting: dorifuto sōkō, a motor sport where the driver intentionally oversteers, causing loss of traction in the rear wheels through turns, while preserving vehicle control.
This winter I planned to do all the brakes on my Opel Gt. I was thinking of upgrading to the new 9" booster that Opel GT Source was advertising. I just got their Christmas flyer specials in my email this morning and they were offering the booster plus the new master cylinder for $199 and a complete set of calipers and pads for $199 until the end of the month. I called them up and Dennis claims that they tested the new set up and it actually stops better than the big brake set up they offer. While I'm at it I'll install my new rotors that I already have and a set of brakes on the rear. Next spring I'll let everyone know the verdict. Maybe some one has already tried the new booster.
I have the whole setup now too, but not installed yet. I will have 75 big brakes up front, Isuzu disks at the rear, 22mm master, 9" booster, SS flex lines. I am looking forward to stopping on a dime and leaving $.02 change.
Does not mean I'm out of Opels however. My wife knows all about my obsession from High School.
I'm sure the gang at OGTS will miss you as well as those who have placed orders with you over the years.
May your new 'love' outlast and out shine your love of Opels.
Oops! It was Gil. Sorry Denis. You all sound the same. I must have talked to you at one point because I have been buying parts from OGTS since 2005 when I started working on my GT. You must still be there in spirit!
What I'm wondering is how I've worked on 2 Opel GT's, and asked a lot of Opel "Guros" questions and yet no one has told me about the OpelGt Source?!?!?
Mandle, it's the place to go to for great parts. They are forever coming out with new parts. I once asked them if the had stainless steel door sills because any used once had as many little dents as mine. Shortly after they were stocking them. They listen to what their customers are having difficulty finding and then look into making those parts available.
Just wondering if anyone that ordered the OGTS Holiday Brake Bundle (booster and MC) has completed it yet? How the work went? Any modifications needed at all?
I have the whole setup now too, but not installed yet. I will have 75 big brakes up front, Isuzu disks at the rear, 22mm master, 9" booster, SS flex lines. I am looking forward to stopping on a dime and leaving $.02 change.
can someone tell me about the isuzu disk brakes a little more like what one what year and what do i need to get them on the opel gt or a link to the thread thanks
Just wondering if anyone that ordered the OGTS Holiday Brake Bundle (booster and MC) has completed it yet? How the work went? Any modifications needed at all?
I'll have the installation of the booster, mc, calipers, and vented rotors done by Tuesday. I've completed the caliper/rotor part, so far. My recent thread about "wheel spacers needed" says what I did/have to do to make the VENTED rotors to work. If you have the normal solid rotors and 75 calipers, then I don't know anything about them specifically.
LOL what is taking you so long ..in NY thay would had that car strip and on crates by now LOL
Ha! Well, the honest answer is that I'm old and slow and it's cold outside.
But your comment reminds me of a little tradition we have amongst my fellow Postal mechanics when someone gets sent out for weeks of training. While you're gone we do something horrible to your big rolling red tool box. Forkilift it up on the roof, wrap it with so much shrink wrap that it looks like a mummy, paint it pink and decorate it with flowers, or, like we did with one guy's from NY, totally strip it(tools, doors, wheels, etc.) and leave it sitting on cinder blocks.
Back to the subject of this thread, the only problems or hurdles I potentially see with the mc and booster installation are:
a) Bench bleeding the MC
b) Trouble swapping old corroded brakes lines over to the new MC
c) Any adjusting of the "brake rod"-to-booster for pre-load if necessary
I've got new brake lines, so I don't foresee a problem with the swap. Bench bleeding the MC just seems messy, but doable.
What I personally have no clue about is the adjustment, if any, of the nut that attaches the booster to the rod. Is there preload or do you just lock it down at the static position?
I finished installing everything today: Bigger booster, bigger master cylinder, '77 BMW 320i ATE-type vented rotors and calipers, and braided metal flex lines. Unfortunately, one of the calipers came with the spring clip for NON-vented rotors and it's been a real PITA to track down the correct one. Supposedly, Centric is going to send me the correct one.
I get the impression, after a lengthy search, that vented rotors and the calipers for them were not standard issue on those BMW's and may have only been available on Euro-cars. Maybe someone out there knows definitively what the situation is.
The installation:
I had my GT completely disassembled 4 years ago and I'd installed new brake lines and cleaned and painted the oem mc and booster and reinstalled them while the car was still stripped. Much easier to get at everything. It sucked getting them out again with the car all assembled.
Surprisingly, the 60% bigger booster went in easier than the smaller oem one came out. One suggestion to folks: If you haven't dealt with any rewiring of your headlights and horns or if you're planning on doing any mods like fog lights or need to run extra wires to your battery for ignition systems, etc. DO THEM NOW. The bigger booster intrudes even farther into that already tight wire bundle area forward of the radiator support.
The new master cylinder is actually about 1/4" shorter and that went in easier than the old one came out. I put the booster in first(Make sure to get that long nut from the booster started on the brake pedal shaft before you tighten it down), but I left the nuts loose so that I could cock it at an angle to aid in getting the mc attached to it. I attached the reservoir to the mc before installing, bench bled it, and installed hose clamps to the hose that facilitates the right angle offset of the reservoir. I don't know if it's common or not to clamp that hose, but mine was originally just pressed on. Jiggling the mc into position can knock off the hose and if there's fluid in it this messy job will get messier.
Reattaching the brake lines was worse than pooping yourself in bed and then tossing and turning all night.
The one closest to the booster went right in. The one that goes in at the bottom in the front took me an hour and a half, caused me to invent 5 new cuss word combinations, gave me spina bifida, and will require years of psychological therapy to stop the flashbacks from re-occurring. The mc outlets are in just slightly different distances from the oem and if the angle of your lines are off by just one degree the fittings on your brake lines won't start threading in. Laying on top of your engine and using every tool you own, you ain't gettin' them lines on if the angle ain't right. I just couldn't get an accurate sense of a true perpendicular until I started looking through the front grill. I must've hand tweaked that bottom outlet line 3 dozen times before I finally stumbled upon the right angle and the fitting started screwing in.
According to the FSM, you adjust the brake push rod so that there's 1/4" of free movement of the pedal before it meets resistance. Adjusting that and getting air out of the system is going to have to wait until I receive the caliper clips. I'll have pics of everything and final comments, probably by next weekend.
I get the impression, after a lengthy search, that vented rotors and the calipers for them were not standard issue on those BMW's and may have only been available on Euro-cars. Maybe someone out there knows definitively what the situation is.
The vented rotors were used for the first production year only. They switched to solid rotors for the remainder of the car's life (at least in the US). A one-year wonder. Hence the rarity.
As you all know, I have a minute amount of knowledge about hydraulics and braking systems. I have evaluated the OGTS brake system and it should perform well using stock or upgraded components.
The 22mm master cylinder is not an upgrade. By increasing the bore of the M/C, you decrease pressure and also decreases compliance therefore, you have more delivered volume at less pressure. The 22mm M/C used with a stock booster, the pedal travel will be reduced and will make you press harder on the pedal to obtain the same result.
The 9" booster is an upgrade, due to the fact that you now have an extra few hundred pounds of assist when you press the brake pedal. I believe I posted all of the math involved in several threads some time ago. The stock master cylinder used with this booster will make you press the pedal softer to get the same result.
Now the good part. If you increase the assist pressure and decrease the M/C pressure, it balances out and you will have a greater yield with less applied foot pressure. In other words, the combination will make you press the pedal the same as before to obtain the same result but your pedal travel will be reduced. This solves the compliance problem of having 4-wheel disk with stock booster/master combo.
There are several threads that explained in great detail what booster will fit the opel with which master cylinder.
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