Servo vacuumed INFO

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redm6gtr
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Servo vacuumed INFO

Post by redm6gtr » Fri Mar 03, 2017 1:55 pm

Does anybody no how much vacuumed is produced by the V8
I think I need to fit a 12volt vacuume pump to improve the brake servo/master cars braking
Thanks for any advise
fordpop52@aol.com



DaveEFI
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Post by DaveEFI » Fri Mar 03, 2017 2:29 pm

Pretty well all production vehicles fitted with the RV8 managed with a vacuum brake servo run from the inlet manifold.
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Blown v8
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Post by Blown v8 » Fri Mar 03, 2017 4:33 pm

I used to run with twin servos,with a high lift cam on a blown rv8 with no problems

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stevieturbo
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Re: Servo vacuumed INFO

Post by stevieturbo » Fri Mar 03, 2017 11:19 pm

redm6gtr wrote:Does anybody no how much vacuumed is produced by the V8
I think I need to fit a 12volt vacuume pump to improve the brake servo/master cars braking
Thanks for any advise
fordpop52@aol.com
That very much depends on the engine.

But I can see very few applications needing an electric pump.
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

garrycol
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Post by garrycol » Fri Mar 03, 2017 11:33 pm

If you are having problems you then need to look at the plumbing to the booster (do you have it off the right takeoff - the pipe/outlet is about 10mm in size) or you have a booster problem.

If the problem persists you could always put in an alternator from a TDI or TD5 which has a inbuilt vacuum pump.

But there is no issues in an RV8 providing enough vacuum

Garry

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ChrisJC
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Re: Servo vacuumed INFO

Post by ChrisJC » Sat Mar 04, 2017 9:08 pm

redm6gtr wrote:Does anybody no how much vacuumed is produced by the V8
I think I need to fit a 12volt vacuume pump to improve the brake servo/master cars braking
Thanks for any advise
fordpop52@aol.com
A Rover V8 in good condition (like pretty much all petrol engines) will pull an almost total vacuum under overrun conditions.

Chris.
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R/R P38 4.6 V8

redm6gtr
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Rover V8 brake issue

Post by redm6gtr » Sat Mar 04, 2017 10:49 pm

Guys
The rover is fitted with a fast road cam the inlet is an Offernhouser fitted with a pair 45 Weber carbs also a Mallory dist
The brakes were a 7 inch servo with a mark 2 jaguar master
They both needed replacing so I fitted a new servo with a 1 inch bore master
A mistake it should have been a 7/8 bore
There is a one way in the servo pipe
So now I have another master on order and will fit a 12 volt power servo pump from a BMW/VW for extra vacuum
So we will see how it goes

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stevieturbo
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Post by stevieturbo » Sun Mar 05, 2017 12:15 am

are you sure your existing servo is fitted/adjusted correctly and actually holds vacuum ?

Whatever level of vacuum that may be
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

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Post by unstable load » Sun Mar 05, 2017 4:52 am

I'm with stevieturbo here... are you sure the Booster is good? You shouldn't need additional gubbins if it is all good.

The only difference a bigger master cylinder has is more pressure required on the pedal, boost is not affected by the M/C.
Cheers,
John

redm6gtr
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Servo

Post by redm6gtr » Sun Mar 05, 2017 9:11 am

Brand new servo just fitted

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Post by mike-b » Sun Mar 05, 2017 2:56 pm

Others reading this may well know better but to raise a point - Would a leaking inlet manifold not play a part of the problem, or even be it?
Mike B Drives a 1984 Mk2 Granada ghia V8.

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Post by ChrisJC » Sun Mar 05, 2017 7:06 pm

You could measure the vacuum........

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Post by DaveEFI » Mon Mar 06, 2017 9:18 am

mike-b wrote:Others reading this may well know better but to raise a point - Would a leaking inlet manifold not play a part of the problem, or even be it?
I'd have thought you'd notice that by poor engine performance before the brakes?
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stevieturbo
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Post by stevieturbo » Mon Mar 06, 2017 2:20 pm

DaveEFI wrote:
mike-b wrote:Others reading this may well know better but to raise a point - Would a leaking inlet manifold not play a part of the problem, or even be it?
I'd have thought you'd notice that by poor engine performance before the brakes?
Possibly...but I dont think there has been a proper explanation of what is even wrong with the brakes ?
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

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Post by garrycol » Mon Mar 06, 2017 10:37 pm

Yes - is the booster connected to a small bleed port in the manifold or a proper large bore bore specifically the size for a booster? Also the brakes seem to be a mish mash of components that may not be compatible with each other.

I doubt a vaccum pump will fix the issue if the same size plumbing as is in place now is used.

The RV8 develops plenty of vacuum - as evidenced by the hundreds of thousands of setups around the world that are working fine - so there is something wrong with the OPs set up not the vacuum.

garry

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