Brake system upgrades and brake booster deletes... make some room

[Unknownvr4]

subscribed.

[mehrshadvr4]

You are going to need a massive pedal move and extra leg pressure to get enough pressure out of your non boosted break system to stop the car. Specially a heavy car like ours. You can try tilton booster delete kits.

[J. Fast]

Doing a little more research on this I discovered a fantastic article from Grassroots Racing which make sense of everything. It's a golden nugget of brake system operation and design.

One thing I would love to know is what is the OEM brake booster boost ratio? Does anyone know if the brake booster force info is published? I couldn't find it in the manual. The would really help determine the optimum size master cylinder and save me some coin on trying a few different ones. Oh, and mehrshadvr4, could you not just relocate the pickup point on the OEM pedal assembly to change the lever arm ratio?

Good stuff right here.

[anyonebutme]

OEM booster ratio is in the TIM. From the top of my head the brakes are 9:1 and clutch is 5:1? The NA booster that I installed on my car is 7:1 or 8:1?

[mehrshadvr4]

There are many ways to increase pressure. You can make the brake pedal longer or go with larger master cylinder or even both but either way you'll have longer stroke with your pedal .

[anyonebutme]

that's what she said?

[J. Fast]

OEM booster ratio is in the TIM. From the top of my head the brakes are 9:1 and clutch is 5:1? The NA booster that I installed on my car is 7:1 or 8:1?

Info was right where you said. What's the deal with the two ratios for AWD brake booster? Is that the front to rear split or is the 9:1 for the Spiders? The 8:1+9:1 is confusing.

Should be able to figure out my axle pressure outputs with this info and the math from last post.

[green-lantern]

Nope. I've never met anyone who has missed the booster after removing it, but all of them added a longer pedal ratio in addition to changing the master diameter.

that's what he said?

[anyonebutme]

it's a double booster......the cutaway makes it clear.....it's 2 boosters in tandem, both acting on a single rod, not split for bias. They do that so it acts as a larger booster but has a smaller diameter to fit in the cramped engine bay.

[J. Fast]

So to be clear the brake booster net output on all wheel drive is 17:1 (8:1 + 9:1) not 8:1, yes?