disabling secondaries idle?
03-07-2011, 08:38 AM
#12
6th Gear Member
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Join Date: Oct 2006
Location: Cork, Ireland
Posts: 6,417
hardened but the ball popped off at the same time, so i guess that's what saved me :-) rocker fell of the valve so it couldn't cause more damage
I will go down the road of trying that with the rally pac. There are some devices from MSD/Crane etc that will use rpm trigger of box and will cause that voltage drop. So from this it should work. so question is: add another box, or just install aftermarket gauge.
aftermarket gauge has been done before (jgstang)
however hacking up a good rally pac is no option in my opinion. I'd rather sell it and buy a rotten one to refresh.
Since I have the rev limiter there's less need for rpm gauge anyway. By now I know what just before revlimiter rpm sounds like :-)
Kalli
I will go down the road of trying that with the rally pac. There are some devices from MSD/Crane etc that will use rpm trigger of box and will cause that voltage drop. So from this it should work. so question is: add another box, or just install aftermarket gauge.
aftermarket gauge has been done before (jgstang)
however hacking up a good rally pac is no option in my opinion. I'd rather sell it and buy a rotten one to refresh.
Since I have the rev limiter there's less need for rpm gauge anyway. By now I know what just before revlimiter rpm sounds like :-)
Kalli
03-07-2011, 10:21 AM
#14
5th Gear Member
Join Date: Apr 2007
Location: Texas Hill Country
Posts: 2,100
Howdy Kalli...been a while...had to make some money to work on the car so that kept me away from the forum.
I do not know a bunch about Demons, but with Holley's you can get rid of the bog by having more of the transfer slot open during idle but that raises your idle speed and limits what affect the idle screws have on the idle AFR because more un-metered fuel is entering the engine via the transfer slot.
I am running a 245ish duration at .050 with .640 valve lift. When I try to run an idle speed less than 900, the AFR jumps around as does the manifold vacuum. A little more rpm lines it out. This is because of the valve overlap. The more overlap, the rougher the idle. Those types of cams run better at higher rpms which is why race cars have the kaachunk kaachunk kaachunk at idle. I am running about 63.5* of overlap.
Any idea how much overlap you have?
I do not know a bunch about Demons, but with Holley's you can get rid of the bog by having more of the transfer slot open during idle but that raises your idle speed and limits what affect the idle screws have on the idle AFR because more un-metered fuel is entering the engine via the transfer slot.
I am running a 245ish duration at .050 with .640 valve lift. When I try to run an idle speed less than 900, the AFR jumps around as does the manifold vacuum. A little more rpm lines it out. This is because of the valve overlap. The more overlap, the rougher the idle. Those types of cams run better at higher rpms which is why race cars have the kaachunk kaachunk kaachunk at idle. I am running about 63.5* of overlap.
Any idea how much overlap you have?
03-07-2011, 12:26 PM
#15
6th Gear Member
Thread Starter
Join Date: Oct 2006
Location: Cork, Ireland
Posts: 6,417
heyyy urban :-)
nice to hear from you. long time no see.
very same effect here. just below the idle in that video everything goes pairshaped. afr jumps or goes lean and manifold vaccum looks like I had some valves not closing (vibrating).
this is my cam:
http://www.compcams.com/Company/CC/c...?csid=800&sb=2
and from what is suggested here intake opens 28 BTDC and exhaust closes 26ATDC, which gives me an overlap of 54*
i think by now I'm just putting this down as 'normal' with that cam
Kalli
nice to hear from you. long time no see.
very same effect here. just below the idle in that video everything goes pairshaped. afr jumps or goes lean and manifold vaccum looks like I had some valves not closing (vibrating).
this is my cam:
http://www.compcams.com/Company/CC/c...?csid=800&sb=2
and from what is suggested here intake opens 28 BTDC and exhaust closes 26ATDC, which gives me an overlap of 54*
i think by now I'm just putting this down as 'normal' with that cam
Kalli
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