puff of blue smoke at higher rpm decel

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mk e
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Re: puff of blue smoke at higher rpm decel

Post by mk e » Sun Feb 11, 2018 7:34 am

Belgian1979 wrote:
Sun Feb 11, 2018 3:14 am
Thanks. To explain the iac system a bit : if throttles are opened further, the effectiveness of the IAC to control the idle rpm is reduced because more air flows through the throttle. So you do not want to set the throttles at idle so that when hot, you reach your rpm target without iac. In that way there is no possibility to compensate for things like AC,...
That's backwards. Set the warm idle, in neutral no AC or anything else on and IAC PLUGGED. That is the minimum amount of air you need. Then when you need more air the IAC supplies it. if you want the IAC working all the time you could go 100 rpm below warm target but I've never found a need. My set up is DBW but even with that I set a min throttle position and that is warm idle and IAC can only open from there.
I'm thinking of make a sort of crossover tube between 2 1/4' lines and from those 2 tees go to short 3/8 lines that connect to the runner. That way a cyl would be able to pull from 2 lines at the same time and capacity is effectively doubled.

However, I've not found a suitable tee with 1/4*1/4*3/8.
That should be no problem if you can find the fittings and is a good idea I think. You could put the canister in back somewhere with a single say 1/2" line coming off then tie in the cylinder with 1/4 to that central line with each cylinder having about the same length of 1/4" line...lots of ways to set it up.
Mark
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Belgian1979
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Re: puff of blue smoke at higher rpm decel

Post by Belgian1979 » Sun Feb 11, 2018 11:10 am

Most recent idea :

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Note that 2 lines going to the manifold are here in 1/4. I could make these 3/8, and to minimize amount of fittings, I could just drill a hole and glue them in with the high temp 2K glue I have.

If I really want it to work as it should I would probably need to throttle the air so I can get them perfectly even so that the AFR's are even

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