Brake Fluid Type dot4 synthetic or dot 5

[DButler]

I have currently put a twin turbo setup on my car and my down pipe is nearly touching my master cylinder at one point and then it gets away from it. With it being so close at the end of the master cylinder I am worried about brake fluid overheating. I am looking for suggestions on what some of you would do of have done. I was going to run a dot 5 fluid but they are silicone based and I have read that they are not really that good. It said it will cause you to have a spongy pedal. I have looked at going with a synthetic based dot4. Any suggestions. Thanks

[silver69camaro]

I would run a higher-end Wilwood fluid with a higher boiling point. Make sure the DP is well wrapped.

[DButler]

Any special wrap you recommend or just regular header wrap?

[Apogee]

I'd suggest running a DOT 5.1, non-silicone base fluid. The fluid Matt suggested above meets the 5.1 temperature requirements, similar to DOT5 silicone but without the downside.

Can you swap your master cylinder to something with a smaller body? There's not a lot you can do with header wrap or heat shields if there isn't any room to install them.

Tobin
KORE3

[DButler]

Yeah I am running the smallest booster possible with a late model style master cylinder. The master cylinder is like a 95 camaro mastercylinder.
I talked to Wilwood and they suggested EXP 600. I just dont want this to cause my brakes to malfunction. How hot do you think the down pipe will get with wrap and without if I can mangage to get it on there?

[DButler]

By the wya the car is a 67 Camaro, so you will know how far the master cylinder sticks out.

[Yoda4561]

Dot 5 silicone fluid is a big fat no, the only advantage is that it doesn't eat paint, so if it's just a trailered showcar it'll work great. Use a good DOT4 or DOT 5.1 fluid for any serious driving. DOT3, DOT4, and DOT 5.1 are cross compatible. The best DOT4 synthetics have specs exceeding the minimum for 5.1, ATE Type 200 is a popular choice for its high wet/dry boiling points and reasonable price. The Motul 600 and Brembo LCF600 have higher dry boiling points, pretty much the highest your're going to get, so if those don't work then you'll need to find other solutions.

[DButler]

Ok thanks. I was going to order Wilwoods, but I am trying to carry my car to the dyno saturday and tune it, but I have to finish brakes. Looks like I may just be waiting. Do you think synthetic Dot4 would work probably?

[silver69camaro]

I'd consider switching to manual brakes, which should move it away from the DP.

[silver69camaro]

Do you think synthetic Dot4 would work probably?

It will be just fine. Just keep an eye on it.

[DButler]

I really appreciate your help...if I which over to manual brakes what master cylinder do you recommend? A tandem Wilwood? I am running an 8" booster with a late model Camaro mastercylinder. Do you think I will notice a difference whiching over to a Wilwood Tandem thats manual?

[Skip Fix]

FWIW My TA has had silicone DOT 5 in it for almost 20 years and NO spongy pedal and has been HARD street driven,autocrossed with road race slicks for years, and pulled me down from 128 mph 1/4 miles with never a bad pedal feel.

[DButler]

I had a guy tell me yesterday he runs it in lots of sports cars and have for years just fine. I have heard good and bad things about it. I called Wilwood and they said stay away from it unless its a trailered hotrod. I dont know if they where saying this to sell me their product or what I think they offer a silicone based brake fluid as well. I guess I am goning to try synthetic dot 4 and if it doesn't work I will go a different route. May which to manual brakes.

[T_Raven]

From what I understand, just general info to put out there, DOT 5 doesn't absorb water therefore any moisture in it will be able to boil and that's why the pedal feels spongy. That's why brake fluid is designed to absorb water, to avoid a spongy pedal.

[Skip Fix]

I can tell you for sure mine isn't a trailered hot rod! Keeping a good sealed system and there should be little water in the lines or calipers.

[silver69camaro]

I really appreciate your help...if I which over to manual brakes what master cylinder do you recommend? A tandem Wilwood? I am running an 8" booster with a late model Camaro mastercylinder. Do you think I will notice a difference whiching over to a Wilwood Tandem thats manual?

Any tadem MC at about 7/8" to 1" should work OK, depending on your calipers, pedal ratio, etc. You'll notice the difference, it will take about 50-80lbs of pedal effort for a hard stop. Some like it, some don't. It sounds like it would give you the room you need.

If it were me, I'd run the car real hard and get it nice and hot, then stick a thermometer of some sort into the MC resevoir. If it's near the boiling point listed on the bottle, it's too hot.

[DButler]

Thats what I am going to do because I really want ot keep power brakes. if it doesn't work right then I will which to manual. I appreciate your help and I will let you know how it does.

[TnBlkC230WZ]

I'd suggest running a DOT 5.1, non-silicone base fluid. The fluid Matt suggested above meets the 5.1 temperature requirements, similar to DOT5 silicone but without the downside.

Can you swap your master cylinder to something with a smaller body? There's not a lot you can do with header wrap or heat shields if there isn't any room to install them.

Tobin
KORE3

X2. Also called DOT 4+. It can be hard to find in the parts stores but but Mercedes and BMW stock it as standard replacement fluid.

[DButler]

I have decided to go with manual brake setup. The mastercylinder is just too close for my likings. Running 4 wheel disc what bore size should i go with?

[a67]

I have decided to go with manual brake setup. The mastercylinder is just too close for my likings. Running 4 wheel disc what bore size should i go with?

What is the effective piston area of the front calipers?

Bob.