Dennis
Check your float bowl levels. You may be running out of gas.
... I would say that your problem is in the carb, check your float levels. 
Ignition problem
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 989
Likes: 13
From: Gloucester Point VA
Ignition problem
I have a problem with the '66 I purchased in May. The car has had a high speed miss that I figured I could correct with normal tune up fixes. I've since changed the coil, rotor, cap, plugs and I've checked the plug wires with an ohm meter and they are fine. You'll notice that I didn't mention anything about points since this car has TI ignition. The ignition coil I installed was for a TI system and I've double checked the resistance of the coil and it is correct. I pulled the amp apart and it has the new updated electronics and the pick up coil checks out good too.
None of these actions has improved the problem. The car runs great up to 3,000 to 3,500 RPMs and then starts breaking up. Anyone got any ideas?
None of these actions has improved the problem. The car runs great up to 3,000 to 3,500 RPMs and then starts breaking up. Anyone got any ideas?
Race Director
Joined: Mar 2009
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I would check the side play in the dist shaft top end. I had the same problem with dwell fluctuation at high rpm. Good luck.
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Safety Car
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Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 989
Likes: 13
From: Gloucester Point VA
Gm
The ignition system on my '66 is the optional system that was offered in the mid 60s on Vettes. It has a distributor with a magnetic pick up that generators a pulse that's sent to the amp. The amp increases the amplitude of the signal and sends it to the coil and from there the system works are normal. This system was call a Transistorized Ignigtion (TI).
JP
JP
Le Mans Master
Joined: Sep 2008
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From: Lake Minnetonka, Mn
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If you have a single point distributor laying around, swap that in and give it a try. At least it will only take five minutes to figure out if your problem is in the distributor.
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 989
Likes: 13
From: Gloucester Point VA
I do!
Dan,
I do have a spare distributor, coil, and ballast resistor laying around. If I get sometime this weekend it's one of the things I plan on trying. Biggest problem is getting time freed up, fall around here is a busy time, over seeding and hedge trimming are on the adjenda this weekend.
JP
I do have a spare distributor, coil, and ballast resistor laying around. If I get sometime this weekend it's one of the things I plan on trying. Biggest problem is getting time freed up, fall around here is a busy time, over seeding and hedge trimming are on the adjenda this weekend.
JP
Instructor
Joined: May 2007
Posts: 140
Likes: 1
From: Louisville Colorado
I had a similar an high speed "engine miss" problem on my 245hp '57. It turned out that the carbs were jetted way too rich. After replacing the metering rods and jets w/ correct ones, the car ran fine. As an fyi, the previous owner had paid large $'s to have the carbs rebuilt by a professional rebuilder in in FL and for some reason they had installed the wrong metering rods and jets (they weren't even close).
Gerry
Gerry
Team Owner
Joined: Aug 2007
Posts: 58,061
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Army
All of the above are good suggestions....my carbs originally had the wrong needle valves and seats too...in my case the super-rich condition resulted in poor running across the RPM band and was most noticeable by the sooty, black crud on the spark plugs. This same indication would be apparent on too cold of a plug in most cases..
Instructor
Joined: May 2006
Posts: 211
Likes: 0
From: N. Tustin Ca
You said Higher RPM's,
More missing under acceleration or just cruising at Higher RPM?
Ever happen when foot not on gas pedal?
More when cornering? then straight aways?
Any one plug look wet or different then others after a hi RPM run?
Is there ever a backfire?
is there a "cough" or sputter? or just a short misfire?
There are a lot of things it could be. Even more then stated above
More missing under acceleration or just cruising at Higher RPM?
Ever happen when foot not on gas pedal?
More when cornering? then straight aways?
Any one plug look wet or different then others after a hi RPM run?
Is there ever a backfire?
is there a "cough" or sputter? or just a short misfire?
There are a lot of things it could be. Even more then stated above
Thread Starter
Burning Brakes
Joined: Nov 2001
Posts: 989
Likes: 13
From: Gloucester Point VA
Answers
You said Higher RPM's, (3200 RPM)
More missing under acceleration or just cruising at Higher RPM? Hard or light acceleration it doesn't seem to matter .
Ever happen when foot not on gas pedal? No
More when cornering? then straight aways? Never tried it.
Any one plug look wet or different then others after a hi RPM run? No
Is there ever a backfire? Nois there a "cough" or sputter? or just a short misfire? Just a misfire (I think).
There are a lot of things it could be. Even more then stated above
More missing under acceleration or just cruising at Higher RPM? Hard or light acceleration it doesn't seem to matter .
Ever happen when foot not on gas pedal? No
More when cornering? then straight aways? Never tried it.
Any one plug look wet or different then others after a hi RPM run? No
Is there ever a backfire? Nois there a "cough" or sputter? or just a short misfire? Just a misfire (I think).
There are a lot of things it could be. Even more then stated above
JP
