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Vacuum Issues
So I finally had everything read to take the car mustang out after the engine rebuild and rewiring. But I noticed a couple issues and need some help.

1. My intake vac is at 15 inches, but I was told this could be normal with a stage-1 cam (I don't have specs available right now). Its steady and sometimes pulses + or - 0.5 (I have not checked acceleration/deceleration) (@~800 rpm park idle)

2. When i go from park idle (800 rpm) to gear (drive or reverse) my rpms drop to about 400. Could this be timing or vacuum leak?

3. When I was driving, I get a noise from (eeerrrrrrr) from the tranny I think and it does not seem to want to shift out. I will be at 2000 rpm and I just dont get much acceleration. The guy I bought it from said it has a 3500 stall converter and shift kit, so could I just not be hitting it hard enough?

Any tips would help, this is my first rebuild and first car with a carb I have ever worked on.
1) you could make a little more with tuning, i was able to get 17-18 inches depending on how i setup the carb for a drive.
when i first got the engine from the builder it was making 13-15 inches

2) normal with bigger cams. Tune the idle RPMS with car in gear, around 650-700. out of gear it will hover just a tick under 1000rpm.
no vacuum leak

3) I assume you have a automatic, does the transmission have a Vacuum modulator hooked up?
the noise isn't normal, does the shifter move easy through all gears.

Try putting the trans in 1st and then manually throw it in 2nd does it shift at all? you should be able to feel the trans shift through all 3 gears before 50mph. the vacuum modulator has some control over the shift points, but if it will not shift manually or is making noises, then there is an internal issue that needs to be checked out.

If you have a small street cam that 3500 rpm stall converter is way, way, too much, and that is why the car doesn't accelerate good.

[Image: 25rnz1y.jpg]

Thanks for the reply.

Just to make sure I am correct, when adjusting the vacuum:
1. Let car get to operating temp
2. Cap ported vacuum
3. Plug into manifold vac outlet on carb
4. Adjust idle screws (simultaneously) until I get max vac.

I was worried that stall converter might be too much, the guy I bought the car from had tried to turn it into a dragger and gave up it looks like.
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