750 DP alky settings

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Krooser
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Re: 750 DP alky settings

Post by Krooser » Sun Jan 14, 2018 1:29 pm

That brings up another question about the air bleeds... What do I do if anything?

The carb is now setup so the t slots are not exposed until the throttle is opened a bit.
Last place in the B-main is better than anyplace in the grandstands...

Ks Fats
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Re: 750 DP alky settings

Post by Ks Fats » Sun Jan 14, 2018 4:25 pm

Since it does have 18 nights on it I'd leave the bleeds alone until you get it installed and then do what ever the tune tells you to do; easy change from the top side. Last early B/G I was in had .031 on the high and I believe .063 on the low. Ended up with .028 and .065 also leaned the IFR but I'll have to find my notes for the specifics. Seem to remember that those carbs were nearly one to one on the IFR and the idle bleed.

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Re: 750 DP alky settings

Post by Krooser » Sun Jan 14, 2018 11:10 pm

Well I got ambitious tonite and pulled two boosters out with two more to go. All are sized at .180... sounds about right. So it looks like my last concern will be the air bleeds which are the old style non adjustable deals.

I'll order some new .180 boosters.... maybe give them a little massaging? Might re polish the bores in the main body, too.

A .150 stainless needle/seat should work right? Got to see what comes in that QF kit I ordered.

I'm sure learning a lot and it's been very interesting... thanks for all of your continued contributions.
Last place in the B-main is better than anyplace in the grandstands...

Ks Fats
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Re: 750 DP alky settings

Post by Ks Fats » Mon Jan 15, 2018 2:09 pm

While you have the boosters out carefully measure the venturi bores to verify they are round and concentric to the booster; make them all equal diameter and concentric and quit there. Early B/G stuff was done with a flapwheel and a dotco and all over the map. Work on concentricity and equal size and you'll improve the booster signal and help balance the delivery from the boosters. Resist the temptation to polish the venturi, just correct what has been done.

Krooser
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Re: 750 DP alky settings

Post by Krooser » Tue Jan 16, 2018 4:22 pm

Got the carb kit yesterday... .150 needle/seat, 30 and 50 cc pump diaphragm s, blue gaskets... Should be ok.

I'll wait a week or so to get my new boosters... My friend said he would stake them in for me.

One more thing off the list...
Last place in the B-main is better than anyplace in the grandstands...

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