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Hi all, i read some where, can not find it now. that on teh vacum take off on bike carbs you put them in to a tank and them from there to the dizzy,
to stop pulseing, is this true? and if it is any picture of the tank?
And what size pipe i need?
thanks
stuart
This is how I've done it....
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Only problem with connecting them all together is that they will draw air from each other - making them impossible to balance .
A far better solution is to fit non-return valves into each line , then connect them up - thats what I`ve done in my V6 setup .
Mmmm, non return valves, had thought about that, but when the vacuum collapses in the manifold, the valves will hold the vacuum in the pipes and not
manage the ignition.
To balance the rail is removed 4 vac gauges connected - easy.
[Edited on 9/4/08 by r1_pete]
quote:
Originally posted by r1_pete
This is how I've done it....
Yes Mark, I have 'bench tested' the engine on edis limp home, it gave a constant vacuum rising and falling with revs according to the vac
gauge.
Syncronised easily with the 4 gauge balancer, no reason it shouldn't the vac take off's are positioned as per the bike set up.
Only difference when it goes back in will be the 2.0L cams, a cooling system and mjlj.
Cheers....
So do i need to put the 4 take off with non return vaules int o a blow then to the dizzy or not?
stuart
If you use non return valves the vac advance will stay advanced, as the valves will hold the vacuum in the pipework.
The 15mm tube connected to each runner on my system serves as a 'smoothing' vessel to smooth the individual pulses of vacuum.
It was this sort of doubt and uncertainty that made me decide to avoid using MAP on my bike carb installation, and to stick with the TPS that was
already fitted.
I know that MAP may well be the best solution in theory (and probably required for turbo engines) but the TPS is pretty darn close, and a hell of a
lot better than the old dizzy that used to be on the engine!
But it's whatever floats yer boat in the end...
I am still thinck about megajolt, but i will think more once the car is sva, and the mods start.
stuart
HI i have tried it all ways with valves and with out i have tried small tanks and nothing seemed to work very good when i had my car rolling roaded
boggs Brothers removed all the vacuum pipes and advanced the timing this was temporary till i got a modified dizzy from H&H ignitions solutions
tel 01384 261500
Jacko
We had some sucess with joining all the vacume pipes togeter with Y connectors like this
YY
Y
When we were using Twin40's on a short ish manifold, it did give a useable vacume but bot very much of a variation to map with.
When we installed Throttle bodies on a puropse made manifold that was as straight as possible, we tried again and it just wasn't useable.
It was explained to me, which makes sence now... we'd made the manifold and everything else as free flowing as possibe and bike Tb's open
very quickly, that there was very little vaccume created anyway as there was no resistance.
Hence were mapping with TPS, probably not the answer you were looking for..
quote:
Originally posted by r1_pete
If you use non return valves the vac advance will stay advanced, as the valves will hold the vacuum in the pipework.
quote:
Originally posted by clairetoo
Only problem with connecting them all together is that they will draw air from each other - making them impossible to balance .