Planning a gsxr throttle body conversion on the pinto. Want to keep the brake servo. The gsxr throttle bodies have a vacuum take off on each port, I'm thinking of putting each one to a vacuum rail/collector with extra take offs for the map sensor and vac gauge and one larger one for the brake servo. Any thoughts on whether this will be enough vacuum for the servo?

Cheers

Karl

Hi Karl,
When I still had a brake booster installed I had a vac fitting from each port on inlet manifold and used the take off on each throttle body for map.
 
Rhys

Hi Mate,
 
You'll need one take off on each port for the brake booster.
 
I have heard that it's best to plumb the vaccuum take offs into a plenum of sorts for the MAP sensor otherwise you'll get phasing and it'll be all over the shop.
 
Can't you use the TPS rather than a MAP sensor?
 
There is a lot of info on Turbosport about this topic if you haven't already looked.
 
Cheers
 
Matt

Gonna weld a bit of pipe
up and use it as a vac chamber and drill tap some holes for all the vac take offs.

Can I not use TPS and MAP. Gonna be using a megasquirt Ecu?

Cheers for the info will
Check out turbo sport

Karl

You can use both sensors in either case.
If you run a 'big' camshaft Tps load sensing is the go, map sensor gets used for barometric correction in which case it doesn't get connected to vacuum signal, it just stays open to atmo. 
If you go with map load sensing, tps only gets used for transient enrichment calculation. (throttle pump)
 
Cheers

Are there advantages to using both over just one or the other?
 
Matt

With T/B vacuum signal becomes 'unusable' for map sensor tuning. A cammed up engine may have very poor vac signal at idle and low engine speeds, also some engines at higher engine speeds may go to 0 vac as early as 60-70% throttle opening(especialy with largish t/Bs) none of which are usable for map tunning. When tuned in 'TPS' you can get all these areas spot on. dont get me wrong, it can be done in 'MAP', but you will get a much better and 'crisp' tune from a TPS load sens. Its something you should decide initialy as changing latter down the track may entail a whole new remap on the dyno.
 
Cheers
 
 

Matt75

Are there advantages to using both over just one or the other?

Matt

You must use both for correct tune in both scenarios. Not using both will be a compromise. MAP alone will not have transient enrichment, and tps alone will not have Barrometric correction. There is also other functions that can be run from these sensors,  so you should always run them.
 
Cheers

I never knew that.
 
If you were to choose one over the other which one would it be?
 
Matt 

FOR n/a engine with T/b's TPS load sens every time.