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-   -   Inital timing on a BBC 540 (https://www.racingjunk.com/forums/showthread.php?t=21838)

jjam 09-14-2008 05:10 AM

Inital timing on a BBC 540
 
I have a BBC 540 with 9.5-1 dart 320 heads, (pump gas) can anyone tell me what inital timing I need to run? I'm running hot, so it is either the timing or the fuel. I figure I would start with the timing, Thanks

bbchevy 09-14-2008 06:20 AM

Timing?
 
Why would you Worry about Initial Timing?Unless the Motor Never goes over 1000 rpms?
Set it @ 34 to36 @ 3000 and Call it GOOD!
Later
G 8)

dparker 09-14-2008 01:12 PM

Your initial timing should be about 12 to 14 degrees. And it is important to a street car on pump gas!! What I would do would be set my total timing at 34 to 38 what ever you prefer, then work with your advance in your distributor. You can change it until you get your desired intial timing. The intial timing is what you have at idle and the total is what the timing is when your distributer has reached max advance, usually 2500 rpm or more. Your total timing is the most important though. We always lock our advance in on a race cars but pump gas is a whole nother ball game.
Good luck,

ashbros 10-03-2008 01:16 AM

I usually run 34 to 36 as well
check radiator for vapor lock

Tod74 10-03-2008 04:49 AM

My 540 runs good at 38 (locked)...but never been on a dyno that just where it feels best.

bjuice 10-03-2008 02:01 PM

just got my 565ci back from PAR..and it makes 1k hp at a locked 38 degree's.
conventional head motor.

Tod74 10-03-2008 03:06 PM


Originally Posted by bjuice
just got my 565ci back from PAR..and it makes 1k hp at a locked 38 degree's.
conventional head motor.


what heads did you put on that one? Just curious.

bjuice 10-03-2008 03:38 PM

Tod i used what i had which is a set of BB2X 2.30/1.88 with a Ton of extra work including a matched 454r-intake with Tons of Plentum work which includes shortenting up the two front runners.

Par said i could have picked up another 50hp or so if i had went wih the Oval port head. but i couldn't really justify spending all the at extra Money for 50 and some change HP.

But if i would have had to buy a set of heads..i would have went with the oval port heads with a Sniper intake

I didn't realize this because never checked them but the chambers on those bb2x of mine were 128cc's ( large). which had my compression lower than what i thought on my 511ci..

Par had to cut my heads to get the 15.1 compression we were looking for..they are now 117cc....of course this caused for the intake to be cut to bolt up properly

also went with a 4/7 swap.


we gonna see how she runs in the next few weeks...i ran 5.96/5.98 et's at 115 mph with the 511ci ( motor)...i hope this 565 put me in the low 70 range without having to push it real hard. :roll:

Brian


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