Brake servo

[ignatzcatz]

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.

 

[ralphmusic]

What is the car?

 

[911hillclimber]

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.

 

[ignatzcatz]

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]

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

 

[ignatzcatz]

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]

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]

servo install pic

 

[911hillclimber]

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?

 

[ignatzcatz]

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]

This is what the engine is in and here's my Harley

 

[911hillclimber]

356!

 

[ignatzcatz]

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]

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?

 

[ignatzcatz]

Just back from Classic Le Mans, great time with my buddies in 3 other 911's. Missed having our collars felt by the French boys in blue after a three figure blast; don't know where they came from but suddenly got a police Peugeot wagon glued to my tail. I think with the uprisings over the recent shooting, they had more than enough to deal with so we got away without hassle.
Regarding my whizz bang engine for my 356, the crank miked out just a gnats cock over spec so I had no alternative but to get it ground. Took it over to OCS for the cut and polish after magnafluxing and they did a great job in a fairly quick time. I'm not having the crank nitrided A) because the thing is forged steel and therefore tough as old boots B) Following nitride treatment it will quite probably be bent and not just in one plane and C) I really don't need any more delay with getting all the engine bits back together. The crank is with my other machinist now for surgical cleaning, he had some delay getting the timeserts for the engine cases, it needs 27 of them but the shuffle pin work plus boring for the 92mil barrels is complete. The heads are next on the list to be vapour blasted then have all new seats installed and the inlet manifolds blended to the heads. However we've just noticed the inlet manifolds are for 45 Webers, I'm running 40's. So should I get a set of 45's to match, which won't be so good for bottom end performance or do we sleeve the existing manifolds to match the carbs? At the moment it looks like the latter option but I haven't made a final decision yet.
Well I was going to post up a pic of my nicely machined crank but the invite for pics seem to have disappeared, wonderful!