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  #46 (permalink)  
Old 05-14-2009, 03:34 PM
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The results:

I backed off the secondary opening as suggest and raised the IDLE SPEED screw to compensate. Surprisingly it gave me a cleaner 800rpm idle and Im quite happy. I pulled the carb off to see how the openings looked

I have .040 (roughly) opening on that opening which is still somewhat square and I no longer have that larger round pinhole exposed which ISNT supposed to be exposed anyway (from my original pics)

If I did try to put in more secondary opening then rpm goes up but I get a choppy idle. If I leave the secondary as it is, and I increase the IDLE SPEED instead (opening the primary side) I get the same increase in rpm but totally smooth (as someone suggested). Is that because the primary is also dumping more gas along with the air whereas the secondary is air only? Why such a difference between opening either of the 2 sides?

Would those profrom adjustable secondary metering blocks give me more adjustable results? Or other brand? This carb has no secondary metering block as I mistakenly thought it did. While Im very happy with the results at this point I wouldnt mind screwing with even more crap and adding bells and whistles

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  #47 (permalink)  
Old 05-14-2009, 05:01 PM
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The difference is that the secondary just has a constant discharge idle feed, where as the front is adjustable with the mixture needle screws and this is what the carb is intended to idle on. I wouldn't worry about having adjustable rear idle mixture, sounds like you have it where it needs to be now, it just needed the correct balance.
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Old 05-14-2009, 06:56 PM
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Glad you're on the right path.

Just don't forget that by changing the rear blades, there may be need to readjust the idle mixture screws. They should be adjusted first, then the curb idle speed screw after.
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Old 05-14-2009, 07:23 PM
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Quote:
Originally Posted by cobalt327
Glad you're on the right path.

Just don't forget that by changing the rear blades, there may be need to readjust the idle mixture screws. They should be adjusted first, then the curb idle speed screw after.
I believe I did that. I turned em in with my current settings until I almost got a stall, then backed out 1/4 turn and then a little bit more as someone had suggested (both sides). Highest vacuum I could get. From there I corrected my idle rpm with the IDLE SPEED screw and left the secondaries alone

Again, thanks a lot for the help to everyone with an opinion or suggestion. Im sure its not perfect but it was SURE as hell way way wrongly adjusted when I made the post looking at the spark plugs. At least I have a good starting point for finer tuning.
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