Hi does the adjustment on vernier alter the idle? I know it alters power band by advancing or retarding but wondered if would have any effect when at idle?
Cheers
Hi does the adjustment on vernier alter the idle? I know it alters power band by advancing or retarding but wondered if would have any effect when at idle?
Cheers
I'm going to stick my neck out here and say No.
Idle timing is mainly more ignition based I think really. But I could easily be wrong.
You are altering the cam position - if it affects WOT it will affect Idle! Whether it will be significant is debatable but valve opening and closing will be in different places so could affect cylinder filling and exhausting - can't affect one without the other!
I did say I could be wrong..
I still cant say I understand it, but I did find this.
https://www.badasscars.com/index.cfm...rod/prd370.htm
The only thing I did consider is that surely for every degree you either retard or advance the cam on a vernier you would also effectively be changing the ignition timing by the same amount? True or Not?
Last edited by rallyrob; 20-07-2020 at 15:57.
Cheers.would be interesting to see how much diff.iv got 285 cam on stage 3 head with 45s on the vernier its one notch retarded for some reason and was going to put it to zero.doubt if it would alter much.its just iv been sync/balancing carbs setting lean best idle on mixture.
Not true. The dizzy is linked directly to the crank, each with non adjustable sprockets / gears so they are either timed together correctly or incorrectly (accepting that the dizzy angle can be adjusted to affect timing). The adjustable cam sprocket allows the cam to move relative to the crank + / - whilst the crank and dizzy drive remain static.
Advancing of retarding a camshaft within normal limits does nothing at all on a Pinto at idle. Not that it is needed to make any changes at idle. Unless maybe when the cam is totally out of position.
Changing the lobe centers does. But in a Pinto only possible by fitting a different camshaft, same profile grind at different lobe centers.
Even then there are limits but you do see changes in idle (only the idle RPM, rough or not). But it's what I've seen and noted on twin cam engines.
and usual they run the car for years like this, free power when they come in hahaha
In this case you will have to "reset" the idle
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