Pinging/Vapor Lock?

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QuickDart360

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Ok ladies and gents!! Got my dart 360 running again. Swapped cam with a 292 mopar purple cam advanced 4° @ crank and has an fbo distributor with 15° initial and 34° total. Victor 340 intake 850 thermoquad with fatter jetting came off of a drag 440 cuda according to seller. 3.91's out back. Runs pretty well for the 1st 30 to 45 minutes in humid to warm weather about 94°F 1st time out. Then if I get on it it sounded like it pinged slightly not too much but anyway I let off immediately and just feathered throttle. Starts fine not hard starting but idle does get dirty when run for a while. I did accidently put regular gas which has about 10% ethanol and then I added a lucas octane booster but didn't seem to do alot. Car used run well with 93 octane but still had ethanol. Please any ideas to rid pinging?!
 
Ping is a combination of low octane / poor quality fuel, engine temperature, timing advance, engine loading and compression ratio, along with "too much carbon" in the chambers, to name a few
 
You give zero details, really. no static compression ratio, no cranking compression readings. Where is initial and total timing set? "WHERE" is the cam installed? 4* advanced tells us nothing. The LSA is 108 ( I assume) so 4* advanced FROM THERE would be 104 ICL. What did the degree wheel say? ...and if your answer is "I didn't degree it" then I am out, because you don't KNOW where it is and no amount of advice will be correct, I don't care who gives it. The more info you give UP FRONT the better answers you'll get.
 
RustyRatRod said:
You give zero details, really. no static compression ratio, no cranking compression readings. Where is initial and total timing set? "WHERE" is the cam installed? 4* advanced tells us nothing. The LSA is 108 ( I assume) so 4* advanced FROM THERE would be 104 ICL. What did the degree wheel say? ...and if your answer is "I didn't degree it" then I am out, because you don't KNOW where it is and no amount of advice will be correct, I don't care who gives it. The more info you give UP FRONT the better answers you'll get.
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Rusty, don't hold back......why don't you take off the gloves and tell him how it really is??????????:rofl::poke:
 
It degreed in spot on. But went with the advise from other members to advance cam. So from the 108° went ahead 4 more degrees. Timing well just set it to 14° or 15° initial. 34 total degrees timing.
 
Compression sadly don't know exaclty since this motor was put together 16 years ago. It has KB107'S and X-heads.
 
QuickDart360 said:
It degreed in spot on. But went with the advise from other members to advance cam. So from the 108° went ahead 4 more degrees. Timing well just set it to 14° or 15° initial. 34 total degrees timing.
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Ok good deal. Thanks for clearin that up. Ok so the KB107. It probably has "around" a true 9.5:1. So assuming that, I would start with about 15 degrees initial timing with about 36 total all in by about 2500. You'll likely need one of those limiter plates from Don at FBO so the total doesn't end up too much. Just a place to start. Also, You should run a compression test. That average number can give us a clue to compression ratio as well, since we know what cam you have.
 
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I can tell you how to get rid of pinging forever.
My 360 had 11.3Scr and 180/185 psi cylinder pressure, with that 292/292/108, at any installed centerline, and burned 87E10 all day everyday at 207*F minimum coolant temp. The secret?
Alloy heads.
In the end, I pulled that cam and sold it to a racer. It was just too much, for what I wanted to do.
 
AJ/FormS said:
I can tell you how to get rid of pinging forever.
My 360 had 11.3Scr and 180/185 psi cylinder pressure, with that 292/292/108, at any installed centerline, and burned 87E10 all day everyday at 207*F minimum coolant temp. The secret?
Alloy heads.
In the end, I pulled that cam and sold it to a racer. It was just too much, for what I wanted to do.
Click to expand...
Right now the budget will not allow this. Just want to resolve with what I have.:(
 
I run rn12yc champions. Would rn10yc colder plugs help? Still need to run only 93 premium fuel to see if any difference. Also considered cold air to carb. Now just sucking hot air in hood area.
 
I run the 12s at 180 plus psi.
and 207*F minimum cooling temp.
I used to run underhood air.
It didn't seem to be a problem for the chambers.
But getting a decent consistent performance on underhood air was not possible, so I finally clenched and puckered, then made a fresh-air hole.
There are of course other ways to get fresh air to the carb.

But um, up here in Manitoba, the air temp rarely exceeds maybe 37*C, and when it does, it's usually just for a few days in July and only rarely are they all in a row.
37C is about 99*F, if my convertor is right.
 
QuickDart360 said:
I run rn12yc champions. Would rn10yc colder plugs help? Still need to run only 93 premium fuel to see if any difference. Also considered cold air to carb. Now just sucking hot air in hood area.
Click to expand...

Find out what your cranking pressure is FIRST, before you make any changes. Remember what I said in my first post? NO AMOUNT of advice will be correct until we have all of the info. AJ is slick, but he ain't gotta magic wand or a crystal ball. Get us the cranking PSI number and we can really get down to it then. Not just one one but all 8. I know. It's a pain. But you will thank me in the long run, I promise.
 
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