<VV> Re: main jet vs idle

[Padgett]

>  I find it difficult to understand how the main
>jet would affect the idle and the transition or sometimes called the
>progression circuit, during low speed operation.

Agree, all gas is fed to the well though the main jet however the flow 
should be so low at idle that the difference between a 50 and 52 should be 
irrevelant.

BTW this entire issue has been about low speed idle in Drive (under 700 
rpm), no transitional elements should be involved.

Issue was clouded by idler bearing that was only noisy at low rpms.

Yesterday I removed both carbs and replaced the 50 jets with 52s. Only 
change made there than a general inspection to make sure that the PE 
needles were not stuck and there was no sediment.

On reassembly the idle was noticeably smoother and steadier. It is 
certainly possible that I dislodged an obstruction without noticing it but 
the idle was not that bad before, more "not good enough". Would have 
probably never have been noticed on stick car.

The #4 plug stopping firing is bothersome but have seen on rare occasions 
before a plug that just did not do well at low rpms. Are all W8ACs 
purchased in September so not many miles. Not entirely comfortable with 
choice but cheap.

Inspected the #4 plug and other than slight blackening, it looked new and 
was gapped .035" yesterday when performing compression check. Have not run 
much since choice is with rattling idler or without fan.

Now the car has a history of idling well following close attention and then 
deteriorating so not 100% sure problem is solved. Not having many spares 
yet is also an issue and slows things down. (Turkey Rod Run is next weekend 
with Florida's largest swap meet so hope to pick up some essentials).

My Heathkit Ignition Analyzer (1015) is the smaller one and does not have 
all of the features of the more deluxe units so will have to build a kill 
board. Plan also to swap ignition wires though these were recently 
installed by PO and are 8mm Silicone. Is hard to describe in a post but 
acts like a plug that runs fine for a while, then fouls, and then starts 
firing again when revved. May try opening idle mixture a touch more but at 
2.5 turns already.

If nothing else, now I know what a smooth idle for a Corvair feels like and 
have a target.

Padgett