Another timing question - Page 2

92hatchLX · 09-12-2009, 12:04 AM

Start at 12 degrees with spout connector removed, fill up with 91 octane, drive the car and put it under heavy load. If it doesn't ping advance it another degree or two. If you get pinging back it down 2 degrees drive it and make sure you don't get any more pinging and leave it where it's at. I used to run 14 degrees of base timing with 91 octane when I was N/A and it never pinged it just seemed to run good there. Now that I'm boosted my base is at 8 but I'm untuned.

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cornfused · 09-12-2009, 08:34 PM

I started out today at around 30 BDC, went all the way down to 2 BDC to work my way up and it ran like crap! If I remember correctly at around 20-25 BDC it seemed to run pretty well and would break free from a standstill but was idling high. I ended up back at 30 BDC tonight before I came in and it still would bog at a hard take off??

I was also checking this with the vacuum tube ON cause I was told to do so. If I took it off the rpm's would go down considerably???

mjr46 · 09-12-2009, 09:11 PM

I assume you were setting timing with the spout out?? if so 30 base is way to much

cornfused · 09-12-2009, 09:22 PM

This is a carburated motor, does it have a spout? That is an electrical connector right? I left the vacuum hose on though??

mjr46 · 09-12-2009, 09:30 PM

OKAY ... nevermind about that, you wanna see what total advance is, that is the most important, rev motor up to 3500 and check total

cornfused · 09-12-2009, 09:35 PM

OK, I did that when I had it set at about 20 BDC and I believe it increased to around 26-ish BDC. What should it be roughly at 3500 rpm?

cornfused · 09-13-2009, 10:15 AM

So should be around 12 BDC at 3500 rpm with the vacuum hose on??
Also could adjusting the idle screw out on a holley to lower the idle cause it to go too lean and stumble at WOT take off?? or maybe it's idling too low?, I'm working by ear here as my tach is not correct.

Thanks

cornfused · 09-13-2009, 05:59 PM

An update

The cam is a Crower 15512
from website-
PERFORMANCE LEVEL 2 - Most popular Ford hyd roller grind, blows
away Chevrolets. Heavy mid-range.
302 cid / 2400 - 5700 rpm / Redline: 6200 rpm maximum

Grind/lobe center
222HR228
112*

Advertised duration
Intake Exhaust
282* 286*

Duration @ .050"
Intake Exhaust
222* 228*

Gross lift
1.6/1.6
Intake Exhaust
.496" .512"

Ignition is motorcraft distributor with autolite platinum plugs and wires.
Holley 4 barrel
It is currently at 29 BDC at idle which goes up to about 35+ BDC when revved. But it is still bogging on take off? Any lower than 25 BDC and it starts to run like crap and runs better in the 35 - 40 BDC when revving range? Is this too much or normal with this cam?

Thanks