stumped
08-10-2004 | 10:47 PM
#11
Neno the mind boggler
Joined: Sep 2001
Posts: 13,080
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From: toledo oh
Re: stumped
interesting. my scorpion with twin small block 260's does the same thing. after a hard run the idle hangs at about 1500. wonder if there is any one perticular component the we all have in common. mine are basically stock except for cams and intakes. i have the stock T-bolt ignition (old style).
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Throttles- Cleveland Construction 377 Talon
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Throttles- Cleveland Construction 377 Talon
08 OPA Class 1 National Champion
08 Class 1 Geico Triple Crown Champion
08 OPA High Points Champion
10 OPA Class 1 National Champion ( happy now Ed! )
08-11-2004 | 07:50 AM
#12
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From: tropical Cleveland OH
Re: stumped
I'm running a BG carb w/no choke. could be not related but it never did it before I started messing with timing. Well actually I set the timing then had to adjust my idle stop a little to dail in idle so I guess It could be hanging up.
Last edited by JUST ONCE; 08-11-2004 at 07:56 AM.
08-11-2004 | 10:02 AM
#14
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From: tropical Cleveland OH
Re: stumped
Originally Posted by rookie_j
i wonder if they may be running a bit rich (loading up just enough to idle at 800), then after a run they clean themselves out and idle higher. just thinking. i hate carb problems!!
08-11-2004 | 03:02 PM
#17
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From: muskegon, michigan
Re: stumped
Originally Posted by blue thunder
I have a similar problem in both engines, just not as bad. After a hard run they like to go to 1100 -1200rpm at idle. This seems to last a couple minutes then then start dropping back down to normal, which is about 800rpm. I have fooled with both carbs several times and know the butterflies are closing properly. I am leaning towards heated air going into the carb from a hot engine room. Doesn't really make sense to me because I think that would create a rich a/f mix (air less dense) and therefore lower idle. Usually lean causes a high idle. Just thinking out loud here and looking for ideas myself.
BT
BT
08-11-2004 | 04:00 PM
#19
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From: IBX
Re: stumped
No areo, it is n/a.
Don't know the answer Just once, but if we follow that train of thought I could come up with: (Note these are ideas not facts)
thinner oil so oil pump consumes less hp. coincides with normal pressure drop when oil is hot
hotter air charge?
Higher internal fuel bowl pressure due to temp that causes idle circuit problem in holleys. Never had this problem on my qjets (hmmm)
hot tbolt module that when hot advances timing?
Please add on....
BT
Don't know the answer Just once, but if we follow that train of thought I could come up with: (Note these are ideas not facts)
thinner oil so oil pump consumes less hp. coincides with normal pressure drop when oil is hot
hotter air charge?
Higher internal fuel bowl pressure due to temp that causes idle circuit problem in holleys. Never had this problem on my qjets (hmmm)
hot tbolt module that when hot advances timing?
Please add on....
BT
08-11-2004 | 04:05 PM
#20
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Posts: 3,393
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From: IBX
Re: stumped
Maybe it would help if each of us with this phenomenon listed specs. Maybe there are other commonalities. Mine are:
mark 4 - 454s
tbolt 4
800cfm holley double pumpers
msd 6 al amplifiers
mechanical fuel pumps
closed cooling
BT
mark 4 - 454s
tbolt 4
800cfm holley double pumpers
msd 6 al amplifiers
mechanical fuel pumps
closed cooling
BT
