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Author Topic:   High RPM Miss???
Gunner 33
Dirt Full Roller

Total posts: 28
posted May 22, 2004 01:15 PM  
I am having a problem when I get into the high RPM range. I run a 2.5/151 Iron Duke that has a Weber 38 carb, clifford intake and header, MSD 6A ignition, MSD Blaster 2 coil and MSD distributor. When I start the truck up it runs great, nice and crisp response. Once I put my foot into it and it gets into the higher RPMs it starts missing (stuttering and popping). I checked all my plug and cap connections and ignition connections (all good). I changed the plugs and during this I noticed that the number 1 plug was allot cleaner (almost white) compared to the other 3 plugs. After this I started it up and increased the RPMs with my head under the hood and noticed that the number 1 cylinder is missing. Any suggestions will be greatly appreciated. Thanks in advance.

Trapper
Dirt Full Roller

Total posts: 64
posted May 22, 2004 10:08 PM  
You may want to take a close look at the cam lobe for intake of #1 it may be wiped. The condition your describing is the engine burning too lean in the cylinder. It would be the first place I would look. Or it could be a valve out of adjustment. Hope this helps some.

TRAP

Gunner 33
Dirt Full Roller

Total posts: 28
posted May 22, 2004 10:16 PM  
Trap,

Thanks for the reply. I'll take a look at it in the morning and let you know.

Gunner 33
Dirt Full Roller

Total posts: 28
posted May 23, 2004 04:06 PM  
Trap,

I appreciate the help, everything looked good. So I'm gonna dig alittle deeper. I'll let you know. Thanks again.

speedyd1
Dirt Maniac

Total posts: 170
posted May 23, 2004 05:06 PM  
check with ksgerry - krp .he often visits here.

speedyd1
Dirt Maniac

Total posts: 170
posted May 23, 2004 05:07 PM  
can you give me some info on the intake and headers you are using? thinking of switching over to the bowtie.

Gunner 33
Dirt Full Roller

Total posts: 28
posted May 23, 2004 05:47 PM  
Speedyd1,

I sent you a PM on the intake and header. Thanks.

b4racing
Dirt Forum Champ
Total posts: 626
posted May 23, 2004 09:56 PM  
I would check and make sure your battery is good first. Then I would check all connections again especiacally the ground. I would also check for a vac. leak. also one time I havd a carb adapter plate that would not tighten all the way down and that caused it. BObby

Gunner 33
Dirt Full Roller

Total posts: 28
posted May 24, 2004 12:48 AM  
Bobby,

Thanks for the reply. I will check all those tomorrow when I get home from work. Also, could carb jetting possibly cause this? I have not done anything to it since I just put on the intake, carb, header and ignition.

tay27tronnie
Dirt Full Roller

Total posts: 37
posted May 31, 2004 08:32 PM  
Gunner: If you have a vacumn advance on the dist. check to see if the inside of the dist is vibrating at high rpm's if so it could be doing like mine was doing. It was vibrating lose check all the screws in the dist. and try to move the insides of the shaft and mags to see if your dist is vibrating the screws loose. We thighten every screw in it and it still would do it. So we put tie straps on it to help hold the mags in place.

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[This message has been edited by tay27tronnie (edited May 31, 2004).]

Gunner 33
Dirt Full Roller

Total posts: 28
posted May 31, 2004 09:21 PM  
Thanks everyone for replying and offering the troubleshooting support!! Sorry I haven't responded earlier to say thanks but I wanted to make sure that I actually had it fixed. I did everything that was suggested. The last things that I did was run a new ground wire and changed the coil. We ran Saturday night and it ran like a top. Again, thanks for all the support.

Semper Fi!
Donnie

b4racing
Dirt Forum Champ
Total posts: 626
posted June 01, 2004 07:12 PM  
congrats on getting it fixed. If you need anything else just ask someone on here will help.

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