I have been enjoying my AV8 Tudor sedan a lot this summer.. great weather so far up here in Maine and I have been driving it to the beach at least weekly. I am having a bit of a problem with spark. I am running Autolight 216's and after a couple hundred miles they coated with black carbon and if I step on it.. the ol girl coughs a bit. I am running a single stromberg 97.. which has new stock jets .. when the plugs are clean and new runs great.. 200 miles or so.. a little wheezy and coughs on hard acceleration. Should I run a hotter plug..? Recomendations would greatly be appreciated. the picture is from Halloween.. only one I have here at work... thank you Hodad
First of all, I think you either mean a *Stromberg 97* or maybe a stock *Holley 94*...........no such thing as a Stromberg 98......... Now.......I have been running NGK B6L's for many years with no issues.....strong revs and no loading up.......try a set.... Mike Harrison, of the Hot Rod Company sells them at the Alliance discount.... CB
Check the little plunger in the power by-pass jet and make sure its working freely. When I rebuilt my Strombergs this spring, all three power by-pass jets were stuck in the open position. While the top is off, I'd also check the float level.
Take it out on a good, straight road where you can "open it up" in 3rd gear and run it until it stops missing. Will have to repeat every 200 miles or so.
You shoudn't have to worry about jetting with a single standard carb...check as above, check float level, be sure fuel pressure is very low. Then worry about aircleaner...if small hotrod type, road test without it...and find out if advance is working. Stock '49-53 distrib sometimes has severe lack of advance, certain aftermarket '49-53 types can be coming in way too late so you have inadequate advance at actual normal driving RPM's.
...running retarded oft mimics a rich condition, and a stockish flathead that isn't burning excess oil or something is generally not very sensitive to plugs, assuming here that the plug mentioned cross references to somewhere near an H10.
Indicates a rich mixture. I wouldn't try to "bandaide" it by trying hotter plugs. Always keep in mind that everything was engineered properly in the beginning and ran the recommended plugs with no problems. Basically, I agree with Mr. Clean........
The main points...stock Stromberg jetting and H10 equivalent plugs should be pretty close to right for you, so you need to diagnose what is happening and why, not jacking around heat ranges or jets.
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