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I finished rebuilding my 750DP and put it on the car last night. Aside from having the bowls on backwards so the fuel inlets were on the wrong side (d'oh!) it went pretty smoothly.

I started it up at lunchtime, and it idles much better than the 750VS that was on there before (mostly because that carb needs a rebuild too...) I adjusted the float level so that the fuel was *just* peeking over the bottom of the sight plugs. (...and managed to mulch the gasket on the rear lock screw in the process, so I have to replace that.)

I got the idle mixture adjusted to the highest vacuum reading, and set the off-choke idle the lowest it seemed stable, about 900-950 rpm.

At that idle, I'm pulling about 7-8 in of vacuum. It bounces around between 5-10, but that's where it is most of the time.

1) I have the 6.5 power valve installed. Based on the vacuum at idle...should I install the 4.5 instead?

2) My narrow-band A/F meter shows consistently lean, at idle and with the secondaries open. (Haven't left the garage yet though.) I'm running the out-of-the-box 70/80 jets...I was thinking of upping both to 74/84. Good move, too much of a jump, or just do the primaries first?
 

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Sounds like you did a good job.

I'd leave the 6.5 PV in it untill you get to drive it some. At part throttle cruise you'll be pulling 12+" (need to check this) and a 6.5 would open just right as you squeeze the throttle.

I'd also drive it first before doing a jet change. Let your A/F meter tell you what to do.

:devil:
 

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i'd go to 1/4 turn more open than max vacume ,, at max vacume is usually lean , go more open till it has a hard time sustaining the reading , it will become eratic , then close it a bit till it settles out ,, usually works for me
 
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