i just got a vacuum gauge today, and i was wondering how much vacuum do u think i should have at idle with valve lift .443/465, .050 dur. 214/224 and adv dur. 280/290.
Now you have the gauge and you want me to tell you what it reads? Let me think a bit. I got it ,18-20 inches on the gauge. Needle will bounce like a pulse indicator.
I'm not sure on a Cam of that lift / Duration about the pulse...
However on a Stock Setup, they say (Whoever "They" really are...) If the needle bounces on Idle look at valves, Valve train...This, again may go out the window with a non~stock cam.
My Vette pulls 20 at Idle, drops to about 16 on throttle, Then returns to 20...and all is Happy and well in "General Mystery" land...
Sooo I'd say if your in the ballpark , and it runs good ... It should be All Good!
Docimp:
=============
Flying is not dangerous;
crashing is dangerous.
I ran a very similar cam in a 351W, initial vacuum upon installation was 10-12. After serious carb tuning and timing adjustment/tweaking I managed to get 16-18 running a 750 Holley DP on an open plenum manifold. Since this engine was equipped with an automatic the extra vacuum I got from tuning made a big difference in driveability and mileage. This engine actually got 16mpg in city driving with a 3.25 axle in a 3200 pd car afterward.
I ran a very similar cam in a 351W, initial vacuum upon installation was 10-12. After serious carb tuning and timing adjustment/tweaking I managed to get 16-18 running a 750 Holley DP on an open plenum manifold. Since this engine was equipped with an automatic the extra vacuum I got from tuning made a big difference in driveability and mileage. This engine actually got 16mpg in city driving with a 3.25 axle in a 3200 pd car afterward.
I'll agree with 15-17 inches with that cam and a 350'ish engine. The size of the engine has a lot to do with it. It would act like a larger cam if you stuck it in a 283.
16-18, ok cool, thats what ill try and shoot for. you got some pretty good gas mileage, im going to be running a 3.36 gear, through a 4 speed manual. hopefully ill get desent gas mileage.
As far as the automatic tranny goes--, do you have the tranny vac. hooked up seperate or teed off with another vac. line.?
I have it teed off into the manifold with the brake booster?is this bad? still shifts hard...400sb---turbo350
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