How much vacuum for a Crane 288

[dodge freak]

How much vacuum should a "hot" cam like this pull at 1,000 rpms in a 10 to 1 compression 340 ?

Crane Cams 288, Part # 694301


226--230 @ .050 lift .458--.465

I get 13, and not steady but between 12 and 13. Vacuum is quick to rise and become steady as the throttle is open. Engine cranking compression is 150 psi...but just 4 bumps and 7 plugs left in,,,I know, I'm lazy, lol

I thought it be 10 inchs at the most, I want a bigger cam :sign10:

 

[moper]

Have you actually run it? And why is the idle at 1000? If the 340 is 10:1 it should idle lower. I'd also think it should have a little more cylinder pressure. But it should also pull very well. What are you looking for as far as results? Idle sound? high rpm stuff?

 

[bonehead]

look good to me stock will pull 15 in depending on your altitude ,pull all spark plugs to get compression reading as crank speed will efect it

 

[dodge freak]

Have you actually run it? And why is the idle at 1000? If the 340 is 10:1 it should idle lower. I'd also think it should have a little more cylinder pressure. But it should also pull very well. What are you looking for as far as results? Idle sound? high rpm stuff?

Yep, got 150 miles so far on it. Its idling at 1,000 cause I'm still a bit shy on running it slower until the cam is well broken in. Plus my one year old msd tach, which I liked and got for $70 on ebay last year isn't working. I sent the msd E curve dist back to msd for a check up, tech line said its possible the dist needs repair. I running points right now--work ok for being so simple. So I am guessing the 1,000 rpms.

Stinks but it be back in 3 weeks and the motor will get another oil change and be all set with around 500 miles I figure by then.

Then I mess around more with timing, jetting.

Had to go get some exhaust pipes welded the other day. Had to cut them cause new motor sits a 1/2 inch out from the last and pipes would not budge. Today was trans shop for a leaky speedo housing--told I was lazy--no really I thought it was more then just that.

Went to a do it yourself car wash and washed UNDER the car this afternoon. Got alot of old grease and oil off and guess what / engine and trans are bone dry, yea. Seems the heat of them was melting the old oil off the frame and causing drips of oil.

This weekend its power wash the garage floor. And then wipe all the tools down and chests. If its not oil, its sealer-like hi-tack on the sockets, etc.

I don't have enough time in the day it seems.

 

[dodge freak]

My old 318 block-same heads, intake, carbs seen 6,800 rpms max. 6,000 daily. Haven't went over 5,000 rpms yet and only brief 2 to 4 second wot in 2 gear. I'm babying it now and likely be beating on it by the end of the season, ha ha

I would guess the 340 pistons being .130 larger and more compression will want more fuel. Haven't up the seconday jets yet and waiting til my good ignition system is back. Sent the 7 box in for a check up too.

Got get that tach going! going to try hooking it to the neg coil wire soon.

 

[moper]

Ok. Then I'd say give it time and get it tuned before you start to worry it's not enough. If you ordered a burger but only got a bite of bun in the first bite you'd think that burger sucked too...lol

 

[RustyRatRod]

How much vacuum should a "hot" cam like this pull at 1,000 rpms in a 10 to 1 compression 340 ?

Crane Cams 288, Part # 694301


226--230 @ .050 lift .458--.465

I get 13, and not steady but between 12 and 13. Vacuum is quick to rise and become steady as the throttle is open. Engine cranking compression is 150 psi...but just 4 bumps and 7 plugs left in,,,I know, I'm lazy, lol

I thought it be 10 inchs at the most, I want a bigger cam :sign10:

150 PSI is too low for the cam you have now and you want a bigger one? It won't pull a greasy string outta a cat's butt.