I was just wondering if I should get a late model brake pedal box that would utilize a booster? Or should I stay with my 71 brake pedal box in Brenda's GT that doesn't have a booster? Would like some thoughts from someone that has driven a car with both setups. What are your opinions?
Calvin,
I can't compare the two on a MGB, but I can on a TR6. The booster diaphragm failed while on a trip, causing a vacuum leak in the engine. I pulled the vacuum line and plugged it so the engine would run and I could get home. It was over a year before I replaced the booster, but I really couldn't tell the difference with or without.
I don't have a booster on my MG, and don't feel the need for one.
I removed the pedal box and master cyl (w/booster) on my 78. Replaced with the dual circuit non boosted master you have. I'm much happier with the feel not to mention the simplicity.
Depends. I bet Brenda is used to modern, easy to apply brakes. Brake pedal effort is obviously greater with non-boosted brakes, but the overall feel is much better, IMO.
My experience is mostly with my Dad's '63 MGB & my '79 B. MIne are easier with a bit mushier feel. :)
IMHO, a booster is dead weight on such a lightweight car and the more important issue is getting master cylinder selection right. You'll probably want a bigger bore than stock. With the later bracket, there are more upgrade options, but with the earlier bracket I only know of one (unless you'd consider dual cylinders, like a racecar. Have a look at Jim Blackwood's car.) Of course, you only need one good option. I plan on keeping the early bracket while upgrading to 15/16" bore by following the example of Rob Ficalora and Bill Jacobson as shown here: http://forum.britishv8.org/read.php?7,31766
You guys are sharp, Happy New Year!
Awesome!!
Between all of the opinions and suggestions, it was a no brainer to go with the upgrade that Rob and Bill came up with. That write up was easy to figure out. Dan said his brakes work fine. I remember reading all this information in these threads. This website and this group is the best.
Thanks,
Calvin
PS: ordered parts!!
Great topic. I am right now at this decision point.on my 78B. Because I am changing out the 4 cyl to the Rover 3.5, I am also making other changes while it's apart. I pulled the pedal assembly out and painted the box. I was looking at the old booster thinking if I just reinstall it, Murphy's law says it will fail the first week its back on the road. So, I love the idea of just eliminating it. Can I just use my stock master or must I buy a Moss dual line master? Curtis, what are the "other options" you mentioned for the later box?
Gary, Most use the 1" Wilwood or 1" Corvette/Streetrod type of master with larger than stock front brakes. The stock late master was 7/8" and the 7/8" Ford Fairmont or Chevy Monza master would be a good match for the stock brakes.
If you opt to remove your boosted brake master in favour of a manual MC, you will certainly have to change your existing 4:1 pedal ratio to a nominal 6:1 ratio. It can be done for a late RB model (by raising/adding a hole to the brake pedal arm/pushrod) but doing so will raise the MC (about 1/2").
A 7/8" bore MC will be a good starting point for a decent combination of pedal travel and effort.
EDIT: Added photo of modification/reinforcement to MC attachment at pedal box
NewDakotabrakeMC.jpg
If space is the issue and you have pas consider hydro boost.