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Hot!Brake servo

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ignatzcatz
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2022/12/22 18:10:51 (permalink)

Brake servo

I'm deliberating over whether I should install a stand alone servo in my car to give me a better brake pedal. I'm a little concerned over vacuum requirements for the servo, I run Weber 40 IDA's and although I could fit a vac pump I would rather not have this weight and power drain. Also do you think I should fit one of those gizmos that reduce the pressure on the pads when you are running. My car has 944 fronts and early 911 rears. Please don't blind me with science.  

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ralphmusic
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Re: Brake servo 2022/12/22 18:17:59 (permalink)
What is the car?

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911hillclimber
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Re: Brake servo 2022/12/23 11:25:48 (permalink)
I pondered the very same question for mods to my 1973 T a few years ago.
You can now get small system servos for dual brakes that can be squeezed into a 911 bulkhead opening (smugglers box).
Costs are not too bad, around £250 iirc.
 
I am lucky in that my 73 has a 3.2 flat 6 in it from a 1986 911 so has the factory vacuum take off, currently blanked off.
 
The 911 runs a pipe from the engine to the servo through the central tunnel, but no early 911 has any type of servo, so you would need to have a vac take off tapping machined into the one inlet manifold, then run a vac spec tube to the front.
This is still on my To-Do list.

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ignatzcatz
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Re: Brake servo 2022/12/23 12:16:18 (permalink)
On my 2.4 (soon to be a built 2.7) I already run a vacuum gauge tapped from the nearside inlet manifold. What I shall do is tap another take off into the offside manifold then join the two pipes and hopefully this should give me enough 'suck' for the servo. I'm still a bit concerned about any bleed off that would minimally push the pads on whist driving but I'm going to give the servo install a go and sort things out later if it requires further attention. Thanks guys. 
911hillclimber
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Re: Brake servo 2022/12/23 13:05:13 (permalink)
I think there is a one-way valve going into the servo that does that, but not at all sure. 
Please post what you end up doing!
 
Price has gone up!
 
 
https://www.carbuilder.co...emote-brake-servo.jpeg
post edited by 911hillclimber - 2022/12/23 13:10:32

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ignatzcatz
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Re: Brake servo 2022/12/31 18:50:44 (permalink)
I've got a MGB servo ordered, I think it'll be UNF but I can get adaptors for metric fittings. It's only single line but hey ho, if anything goes pop I'll just have to use the handbrake, which actually, I recall, I have had to do so before so no worries. I might well swap the master cylinder as well to be more compatible with the servo. The only minor problem now is going to be where to fit the thing but there is a fair bit of space up front so I shall wizz up a couple of brackets and bolt it on. No news on my semi-race 2.7 yet but there is still a lot to be done. 
ignatzcatz
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Re: Brake servo 2023/01/22 18:54:01 (permalink)
Got the servo and was thinking where to fit it. There is zero room in the engine compartment and I did fancy sticking it in the back of one of the rear wheel arches but then I decided to place the thing as near as I could to the master cylinder to keep the pipework down to a minimum. So it's up front in the well next to the battery and it was UNF so I had to make up a couple of pipes with metric one end and UNF on the other. I also fitted a new VW type 2 master cylinder which only had three outlets, one to go to the servo, one blanked and one for the brake switch. I didn't want to clutter up my engine compartment with additional pipework although it's all braided hoses and AN fittings so I got hold of a vacuum pump which I installed next to the servo. I really wanted a vacuum switch, I can get one from China but I have to order a hundred so instead I bought a timer switch and rigged this up through the brake light switch so when I press the brake pedal the vacuum pump comes on via a relay and the timer switch holds it on for whatever time i set it for. Should work. I can't say how the servo works because the car is currently engineless, (it's getting hi comp 2.8 slugs and all the trick stuff) but I'm sure it will be a good stopper.  
I'll try to upload a pic later, why is this site such a bloody pain 
ignatzcatz
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Re: Brake servo 2023/01/22 20:10:28 (permalink)
servo install pic

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911hillclimber
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Re: Brake servo 2023/01/23 09:58:51 (permalink)
Interesting!
Does this servo the fronts only?
Also, what car is this in?
Pic is not a front of a 911 I can see, so a 914?

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ignatzcatz
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Re: Brake servo 2023/01/25 20:37:26 (permalink)
The servo will operate for all wheels but with everything down and waiting for fluid and bleeding, I'm having serious thoughts about slipping in a line lock into the system. Just got my ceramic coated headers back from Aerocoat over in Gt. Yarmouth, had them finished in a cool shade of titanium and they also powder coated the Eibach springs on my Koni coil overs for the rear suspension. I had the lower screw fixings coated in that goldy cadmium finish so they look rather tasty on the car now. I got the engine tore right down to the last nut and bolt and actually it's not that bad wearwise, in fact if it wasn't for the fact it had a couple of leaks it could all go back together. But, I have the need, the need for, you know what, so it's onto the design 911 website cum big boys toy shop and let's get ordering. 92mil barrel and pistons, hi-comp 101/2 to 1, G40 cams, Wossner rods, ported heads, lightened flywheel, sports clutch and new everything else. Phew, I'm going to have to sell the cat. The thinking, educated and otherwise reckons I should be kicking around 250 to 270bhp with that lot under the bonnet. The dyno over at CCK tuning will tell the truth but it's going to be sometime in the Summer before this lot is back on the road.
I'll try and do some pics tomorrow.   
ignatzcatz
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Re: Brake servo 2023/01/25 20:50:17 (permalink)
This is what the engine is in and here's my Harley

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911hillclimber
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Re: Brake servo 2023/01/27 17:18:39 (permalink)
356!

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ignatzcatz
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Re: Brake servo 2023/01/28 21:19:23 (permalink)
Oops that went a bit crazy with my pic posting. I meant to say riding the Harley will keep me sane while my 356 is off the road and this pic was the one I wanted to post but somehow I couldn't do it. Here's my cool shocks too.And the car is a '62 356B T6 LHD ex San Antonio Texas. As says Lyle Lovett - she's my San Antonio girl.
This is my last post on this crappy forum, I've reduced the size of my pics to 600 v 400 pix and they still wont post. I'm really dont think I'm going to renew either, 80 sovs for a mag full of Ev's. No thanks
911hillclimber
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Re: Brake servo 2023/01/29 19:02:59 (permalink)
I have scaled all my pics for this forum to that size, all is good.
I use Post Image because it is so straight forward.
EVs everywhere is a sign of the times in almost all mags, but quite rare in car club magazines, PP influenced by current factory directions?

Club member since 1988
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