Vacuum signal on independent runner intake

robbinsj

Well-known member
OK, as I'm researching what the ideal intake setup would be, I've looked at a triple Weber sidedraft setup (fabricated intake manifold) as one of the best possible. Pardon my ignorance, but how do you generate a vacuum signal for the distributor etc.? I'm assuming you could tap each runner and join in a common vacuum plenum.....What am I overlooking?
-Joey
 
Do a search on posts by MustangSix, he ran into that problem in his hybrid engine roadster.
 
Mechancal advance. Forget the vacuum advance.

tap each runner for a fitting and tie them together to run the PCV.

Sorry, dialup this week.....slooooow..... :(
 
MustangSix":2pxd4qkx said:
tap each runner for a fitting and tie them together to run the PCV.

And the brake booster (If applicable)
 
Don't have a brake booster at this time but might convert one day. I wasn't thinking about the PCV but, yep, would need to do that. Still concerned about a ported vacuum source with gas prices headed up, the way I understand it mechanical advance only isn't as economical as vacuum and mechanical together....
 
robbinsj":3fxrcv1i said:
the way I understand it mechanical advance only isn't as economical as vacuum and mechanical together....

That is correct,
but IR systems aren't necessarily as economical as running a single carb, either
 
robbinsj":184rcgz5 said:
Still concerned about a ported vacuum source with gas prices headed up, the way I understand it mechanical advance only isn't as economical as vacuum and mechanical together....

Then an IR carb system is not going to be your first choice anyway.
 
Yeah, yeah I know, I could buy a lot of gas (less now than before! $3.20 per gallon as of today) for the money I would spend on modifying the head, fabricating an intake manifold, and getting my hands on 3 Weber DCOE carbs. But lets throw logic out for a moment. The research I've done shows than an independent runner setup, with properly sized, jetted and tuned carbs may actually give better economy than a really poor induction system such as the integral log. Economy rivaling fuel injection with throttle response as good or better. Printed word, websites, etc. have often fallen short of reality in my experience but it is a fantasy I have.....
 
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