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Re: Detonation [Re: JoesMopar] #520162 11/10/09 01:40 AM 11/10/09 01:40 AM
Joined: Jan 2003 Posts: 27,421 Balt. Md 3 383man Too Many Posts
383man Too Many Posts 3 Joined: Jan 2003 Posts: 27,421 Balt. Md	What is your comp ?? It does seem odd that with aluminum heads and the 292-509 comp cam with 32 total timing that it would ping ?? Do you where the cam is degreed at ?? Ron

Re: Detonation [Re: 383man] #520163 11/10/09 09:30 AM 11/10/09 09:30 AM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	Quote: What is your comp ?? It does seem odd that with aluminum heads and the 292-509 comp cam with 32 total timing that it would ping ?? Do you where the cam is degreed at ?? Ron It's not odd he has vacuum advance pulling in a ton of extra cruise advance that today's gas won't allow and when he gives it more light throttle the cylinder pressure rises causing ping which would not have happened in the days of 98 octane regular and up to 106 high test. You have to tone down (limit) the amount of vacuum advance to stop that ping. Vacuum advance is a crude cruise gas mileage device not suited very well for todays fuels. Just found this on his engine "I also used Rhoads lifters" will make it work like a small cam at low RPMS I assume Last edited by Dodgem; 11/10/09 09:41 AM.

Re: Detonation [Re: Dodgem] #520164 11/10/09 09:34 AM 11/10/09 09:34 AM
Joined: Oct 2003 Posts: 7,506 Az Crizila master
Crizila master Joined: Oct 2003 Posts: 7,506 Az	Quote: Quote: put some good octane in there & (1) set your initial where your cam/eng likes it (2) shorten the slots for 36-38 total (vac adv (if used)disconnected) (3) play w the spring combo so you get a fast a curve as possible but staying just under the pinging point as you run it thru the gears @ WOT on your hottest/driest day (4) hookup the vac adv & add as much of it as it will take without pinging (or missing from too much overall timing) @ PART throttle on your hottest driest day. Get each stage near perfect then the next one(& in order) so that nothing is being left on the table. But he stated starting problems when he had 36 total? This is usually to short of slots where the real initial not idle advance is too far ahead for his combo. I like a longer slot to lessen starter kickback and some like shorter slots Oh well tomato tomato? Unless somebody has already screwed around with the dist, it's not likely that the advance slots are too short - nor is he in to the advance curve at 500 - 550 cranking rpm. Again, leave the vacuum advance disconnected until you have the mechanical advance sorted out. I would be interested to know what the cranking psi compression is?? Is the motor healthy - not pushing lots of oil?? Fastest 300

Re: Detonation [Re: JoesMopar] #520165 11/10/09 09:44 AM 11/10/09 09:44 AM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	Quote: Yeah what it would do is just crank longer because of the advance. It was really bad once the motor got warmed up and the only way I knew to fix it was back the timing off. I'll try your suggestions and see if it fixes it. I appreciate all the help as usual. I thought you meant kicking back on the starter and assumed to be doing that at 36 someone must have shortend the slots. no real reason it should have been harder to ignite?? maybe you were timid on the throttle! LOL!!

Re: Detonation [Re: Dodgem] #520166 11/10/09 01:42 PM 11/10/09 01:42 PM
Joined: Dec 2008 Posts: 2,782 USA J JoesMopar OP master
JoesMopar OP master J Joined: Dec 2008 Posts: 2,782 USA	Lol, no I wasn't timid on the throttle starting it. You know how when it's too far advanced it cranks slower and longer before it actually starts? That's what it was doing. The engine is strong, about 60-70 oil psi, compression I would guess is close to the 11:1 range.

Re: Detonation [Re: JoesMopar] #520167 11/10/09 01:47 PM 11/10/09 01:47 PM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	Then you needum mini starter my MP one is some of the best money i ever spent!! LOL!!! After 18 years had it gone over with new brushes, cleaned up armature and they found a couple other things and it works as good as new now.

Re: Detonation [Re: Dodgem] #520168 11/10/09 02:02 PM 11/10/09 02:02 PM
Joined: Dec 2008 Posts: 2,782 USA J JoesMopar OP master
JoesMopar OP master J Joined: Dec 2008 Posts: 2,782 USA	I would try the starter, but the headers on it are a PITA. So basically, Put some good gas in it, plug the vacuum advance port, run my car adjusting the initial timing as needed to sort out the ping, then possibly swap the springs/weights in the distributer then try running my Vac. Adv. as I much as I need and no more.

Re: Detonation [Re: JoesMopar] #520169 11/10/09 02:24 PM 11/10/09 02:24 PM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	Tune completely with vacuum off. you will be able to use 93 but get summer 93. yours may not vary as ours in the cold north! work the mechanical advance idle and what not for a few weeks to get the best total 36 to 38 produces best HP and to get a good idle 900 to 1000 in gear with 22 or so idle advance. tune till till you have no ping under any driving conditions Once you are happy and have not made changes in a couple weeks?? Then and only then you can if you must plug the vacuum advance back in to ported vacuum. I would expect light throttle ping to come back at this point! so with a 3/32 allen wrench in through the hole in the dis vacuum port you start tuning out that ping by turning CC. I would go 3 turns right off the bat. drive and keep going CC till you have no ping under any driving conditions (I personally think the vacuum advance has no place on a performance car especially with todays fuels) By the time you tune out ping it does little anyways. If you were to adjust timing with it hooked up now you would lose all your WOT performance???

Re: Detonation [Re: Dodgem] #520170 11/10/09 02:33 PM 11/10/09 02:33 PM
Joined: Dec 2008 Posts: 2,782 USA J JoesMopar OP master
JoesMopar OP master J Joined: Dec 2008 Posts: 2,782 USA	Ok, I see. I was trying to make sense of all the posts at once. I know what to do now. I might have to try this in the spring due to the driving, work, and winter setting in. I'm going to print this page off for sure. Thanks to all you guys for the help. I always appreciate the input I get from you all.

Re: Detonation [Re: JoesMopar] #520171 11/10/09 02:46 PM 11/10/09 02:46 PM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada

Re: Detonation [Re: Dodgem] #520172 11/14/09 04:13 AM 11/14/09 04:13 AM
Joined: Jan 2003 Posts: 27,421 Balt. Md 3 383man Too Many Posts
383man Too Many Posts 3 Joined: Jan 2003 Posts: 27,421 Balt. Md	Quote: Quote: What is your comp ?? It does seem odd that with aluminum heads and the 292-509 comp cam with 32 total timing that it would ping ?? Do you where the cam is degreed at ?? Ron It's not odd he has vacuum advance pulling in a ton of extra cruise advance that today's gas won't allow and when he gives it more light throttle the cylinder pressure rises causing ping which would not have happened in the days of 98 octane regular and up to 106 high test. You have to tone down (limit) the amount of vacuum advance to stop that ping. Vacuum advance is a crude cruise gas mileage device not suited very well for todays fuels. Just found this on his engine "I also used Rhoads lifters" will make it work like a small cam at low RPMS I assume Forgot he runs a vacum advance. But I run all 38 total timing in by 2000 rpm on the 906 headed 440 in my 63 and it runs great on 92 pump. I have nice quench and never have any ping. Course with vacum advance he could be in the 50's with total timing. I myself dont like to run a vacum advance on my modified from stock engines. But thats because I run all total in by 2000 and tune it that way so I dont need the vacum advance. Ron Last edited by 383man; 11/14/09 06:19 PM.

Re: Detonation [Re: JoesMopar] #520173 11/15/09 10:48 AM 11/15/09 10:48 AM
Joined: Apr 2004 Posts: 271 Dallas, Wisconsin BurntOrange enthusiast
BurntOrange enthusiast Joined: Apr 2004 Posts: 271 Dallas, Wisconsin	Quote: I'm running a Comp 292/299 .509/.509 cam, Edelbrock 84cc closed chamber heads, Holley 870 street avenger carb, MP ignition (distributer w/chrome box). The block has alsobeen zero decked and I'm running KB flat tops. Can't remember the head gasket thickness, maybe .020"? Zero deck and .020 clearance? What's your compression ratio?

Re: Detonation [Re: BurntOrange] #520174 11/15/09 01:29 PM 11/15/09 01:29 PM
Joined: Dec 2008 Posts: 2,782 USA J JoesMopar OP master
JoesMopar OP master J Joined: Dec 2008 Posts: 2,782 USA	Not sure exactly, in the area of 11:1. I don't remember the thickness of the head gaskets, it's been a few years since I built it.

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