which brake system to use ?

[pjv911]

On my 69 project car its time to decide which brakes to use. I just scored a entire 1987 930 turbo NOS new suspension system. The bolt spacing is 3.5" . The setup did not come with the 930 brakes so I want to find out my options. Also I will not be using the turbo rear trailing arms . Instead I will be using carrera arms. The rims are aftermarket (HRE) 17" rims so there is ample space for large calipers. The car is getting a turbo motor and will weigh aprox 2400 lbs . I figure it will need decent brakes. BTW the car presentely has carrera brakes(all new) at all 4 and a larger master cylinder. I did not put the present brakes in and dont know which master it is. Who sells a nice brake kit that will bolt onto my 3.5 spacing and carrera trailing arms.

Kurt Williams

[Randy Webb]

Search for Bill / Verburg / brakes

go to his web page, which you will find from the search.

[pjv911]

I just sent him a pm .

[marcesq]

Kurt:

FWIW: I am running the Carrera rear caliper and rotor, with the Boxster monoblocks on the front with Carrera rotors. My car is just over 2600 lbs and has an estimated 230 hp. The pads are Hawk street. The master is stock 911s (19 mm). Also installed the 993 deflectors on the front. I put 8 track days on the setup and had huge amounts of braking power that never faded.

During one of the events, I had 5 sessions that were 25 mins long at Summit Point where brakes get jammed 2 times within about 30 secs with a good tap inbetween on each lap. No fade whatsoever.

The combo is well balanced and did not require an apportioning valve. Fronts lock up comfortably before the rears.

Set up is on the conversion page.

Good luck.

[Bill Verburg]

Front struts are 3.5", Carrera trailing arms are 3", turbo trailing arms are 3.5"

I would want a minimum of 930 f/r rotors, 304x32 floating fronts(non floating if strictly street and noise is an issue) 309x28 rears.

930 calipers are a bolt on front but need some involved machining rear(see VCIs site) cost will be close to $3k unless you can scare up a good set of used ones.

A little nicer alternative for roughly the same $ is the same rotors w/ 993 front calipers(using axial to radial adaptors) and 965 rear calipers(993 rears can also be used w/ some fitment issues that will need to be addressed)

Another $500 gets you full f/r 322mm Big Reds, a 2400# 300hp car is probably ok w/ the smaller 930 rotors for occasional track use but there is a lot to be said for the extra peace of mind the the 322s will give you.

Unless of course this is a race car where you need to abide by the rules(hard for me to believe but I hear that some actually don/t abide by the rules)

All of the above will want an ATE 23.8 mm non-boosted m/c w/ al front crossmember or a boosted ATE 930 23.8mm m/c like Jack used(lots more $$) but doable

[obrut]

My 2200 lb RS rep has Boxster front on gas slotted 3.2 discs and 3.2 Carrera rears (with the larger pistons) with 3.2 discs with a merc benz 23mm master cyl

Excellent stopping and with great feel/balance - the larger rear pistons was kindly recommended by Bill V and negated the purchase of Boxster rears or a dual m/c

Cheers - Ryan

[marcesq]

Bill or Ryan . . . do you have the MB part number for the 23 mm boosted master. I am looking at that for a winter project.

Thanks.

[Bill Verburg]

Here's an ATE# from a few yrs. back # 3.2123-1003.3 don't know if it's stilll current. I would buy a kit from Steve Weiner though. The kit includes a longer actuating rod(necessary) and some angled fittings that make the lines hook up more convieniently.

You also need to have an aluminum crossmemeber for the big m/c.

[pjv911]

Just got off the phone with Bill V (great guy) after discussing my options I think im going to go with the big reds for front and rear. Thanks guys for your help(bill also suggested the boxster setup) . I just think that for less than $3500.00 (and having all new parts) that the big red kits are the way to go. Looks more impressive too ! Now if only someone out there has a new setup they didnt use ........ Anyone ?????

Kurt Williams

[marcesq]

Thanks Bill . . . I'll check with Steve.

Cheers

[Mark Crowe]

After installing ( finally!) 993 T front calipers and 930 3.3 rears on my 77 3 litre turbo, it is time to address the master cylinder....

I am looking at the ATE master cylinder , part no: 3.2123-1003.3 if available, but have been advised that possibly the ,aster cylinder from a Ford Sierra car would also work, , but I suspect this is more a replace meant for the MC on a booster.

One thing I note from the threads I researched on Pelcian , is a reference to the ATE 23.8 mm MC possibly needing to be used with an aluminium cross member- can any one confirm that this is indeed the case as i do not want to upgrade my stock cross member at this point.

I was also thinking of using ATE boosters that operate off line pressure ( like in the old Alfa GT Juniors) if the need to reduce pedal pressure become a factor, in order to avoid looking for a pedal box assembly- anyone try this concept or have thoughts on it?

Thanks

Mark

[Steve@Rennsport]

Mark,

Since you have an ROW '77 930, can you tell me if your car has boosted or non-boosted brakes? Is the MC mounted in the front compartment or down by the crossmember?

You must use a 23mm MC for those brake to work properly so its simply a matter of choosing the right one, depending on whether you have vacuum-assisted brakes or not.

For vacuum assisted ones, you would use a later 930 MC; for non-boosted ones, you would use a Mercedes 23mm MC of which there are two versions.

[winders]

Originally Posted by pjv911

Just got off the phone with Bill V (great guy) after discussing my options I think im going to go with the big reds for front and rear. Thanks guys for your help(bill also suggested the boxster setup) . I just think that for less than $3500.00 (and having all new parts) that the big red kits are the way to go. Looks more impressive too !

That sure is a lot of unsprung and spinning weight you don't need.........

Scott

[Bill Verburg]

Originally Posted by winders

That sure is a lot of unsprung and spinning weight you don't need.........

Scott

Once again your opinion which you seem to be full of


If you noticed, he was building(this is an old thread) a hot rod 930

I agree many people don't need bigger brakes, but some can certainly use them.

[Bill Verburg]

As Steve noted for '77 930 which should have boosted brakes just buy a late 930('78-89) m/c. Its a bolt on and is 23.8mm.

also as Steve alluded there are 2 different Ate non boosted 23.8mm m/c, the one to use on a non boosted 911 is
ATE (ports face left), # 03-2123-3402.3, current as of 4/04, yes these were oem on some Mercedes trucks

It's better to buy a kit from smart racing or Steve. The kit includes the m/c , the correct operating rod(which is not the same as that used stock), several feed fittings w/ the correct geometry and a length of feed line to complete the install.

[winders]

Originally Posted by Bill Verburg

Once again your opinion which you seem to be full of

Verburg, no one on this forum has more "opinions" than you. So go look in a mirror and roll your eyes at yourself!

Originally Posted by Bill Verburg

If you noticed, he was building(this is an old thread) a hot rod 930

I agree many people don't need bigger brakes, but some can certainly use them.

Yes, I saw that it was an old thread. Someone brought it back to life so I thought I would comment. The OP has a 2400 lbs car. That light a car, even if raced, doesn't NEED Big Reds or the big rotors that go with them to get really great braking.

I made no judgments. I never he said he shouldn't have them. It's up to him. Maybe he wants the coolness factor. Maybe he wants more brake than he needs. Maybe he doesn't care about the weight. Regardless, my opinion is, in fact, accurate: the OP doesn't need them.

Scott

[RWebb]

Bill's opinions are those of an engineer who has thoroughly educated himself on brake systems. HE helps more people in a week on this bbs than you ever have.


I don't know what the OP needs or not. If he just wants bling that would also be his decision(tho not one I'd like to see). If he's tried air ducting and driving changes then this makes sense; or wants to build a period correct, homage, or clone it also makes sense.

[Bill Verburg]

Originally Posted by winders

Verburg, no one on this forum has more "opinions" than you. So go look in a mirror and roll your eyes at yourself!


Yes, I saw that it was an old thread. Someone brought it back to life so I thought I would comment. The OP has a 2400 lbs car. That light a car, even if raced, doesn't NEED Big Reds or the big rotors that go with them to get really great braking.

I made no judgments. I never he said he shouldn't have them. It's up to him. Maybe he wants the coolness factor. Maybe he wants more brake than he needs. Maybe he doesn't care about the weight. Regardless, my opinion is, in fact, accurate: the OP doesn't need them.

Scott

Do you just sit around looking for arguments?

I provide help and factual info, perhaps something that you might want to consider doing

[winders]

Originally Posted by RWebb

Bill's opinions are those of an engineer who has thoroughly educated himself on brake systems. HE helps more people in a week on this bbs than you ever have.

I don't know what the OP needs or not. If he just wants bling that would also be his decision(tho not one I'd like to see). If he's tried air ducting and driving changes then this makes sense; or wants to build a period correct, homage, or clone it also makes sense.

RWebb,

I didn't challenge Bill's opinion or anyone else's for that matter. I said that a 2400 lbs car doesn't need Big Reds and the rotors that go with them to stop the car effectively. If someone wants Big Reds, for whatever reason, more power to them. All I addressed was "need".

In the thread, I didn't see anyone address the concept that Big Reds and associated rotors might be overkill for that weight car. The OP seemed like he might be concerned with weight so the weight of the calipers and rotors seem like a reasonable point to mention. Unsprung and spinning weight are the worst kind of weight to add especially if you don't need what the weight brings. My opinion is that they are overkill.

Maybe I am wrong. If you are going to make an error in brake choice, it is certainly better to have more brake than you need. You and Bill have criticized me for my opinion, but have said nothing to suggest how, from a technical perspective, it might actually be wrong.

Scott

[Bill Verburg]

Originally Posted by winders

RWebb,

I didn't challenge Bill's opinion or anyone else's for that matter. I said that a 2400 lbs car doesn't need Big Reds and the rotors that go with them to stop the car effectively. If someone wants Big Reds, for whatever reason, more power to them. All I addressed was "need".

In the thread, I didn't see anyone address the concept that Big Reds and associated rotors might be overkill for that weight car. The OP seemed like he might be concerned with weight so the weight of the calipers and rotors seem like a reasonable point to mention. Unsprung and spinning weight are the worst kind of weight to add especially if you don't need what the weight brings. My opinion is that they are overkill.

Maybe I am wrong. If you are going to make an error in brake choice, it is certainly better to have more brake than you need. You and Bill have criticized me for my opinion, but have said nothing to suggest how, from a technical perspective, it might actually be wrong.

Scott

The discussion was and is not about whether or not x, y or z setup should be used it was simply a request for info about a setup that was either already installed or was in the process of being installed.


You appear to have a habit of injecting yourself, unnecessarily and often rudely in to discussions, you have only been here a short while but seem to be frequently the source of posts that are less than helpful and more than commonly rude.

Your info may be factual but it is also only tangential to the discussion here and is often presented in a confrontational rather than informative or helpful manner it seems to be far more focused on eliciting friction rather than being helpful. You see this on other boards frequently and you seem to be making a concerted effort to bring that kind of in incivility and dissension here. It will not be tolerated.

If you have something relevant to contribute by all means do so, if you want to start a fight go somewhere else