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  #41 (permalink)  
Old 10-17-2021, 04:12 PM
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I would put a half a tank of gas in, since your gas reads near zero.

Then I would try another known good carb as a test.

Seems you have had a few things wrong, and one would think the advance springs broken was 95% of your issue.

Gary
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  #42 (permalink)  
Old 10-19-2021, 07:11 AM
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Here is what I know about specs. Apparently this is a holley 850 double pumper. Fuel pressure set to 7.5 and running a blue pump. Not sure hows its jetted...but again problem is up high so my guess is it would be secondary jetting if anything. I plan to film the pressure gauge aa I drive and see if pressure is dropping off. It is a dead head style.

I will fill up on gas...but the car has a 1/4 tank on those runs. The fuel gauge is just lazy when it gets lower on fuel.

Video of the run can be seen a few posts back on page 2
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  #43 (permalink)  
Old 10-19-2021, 04:38 PM
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Quote:
Originally Posted by Soundkillr View Post
Here is what I know about specs. Apparently this is a holley 850 double pumper. Fuel pressure set to 7.5 and running a blue pump. Not sure hows its jetted...but again problem is up high so my guess is it would be secondary jetting if anything. I plan to film the pressure gauge aa I drive and see if pressure is dropping off. It is a dead head style.

I will fill up on gas...but the car has a 1/4 tank on those runs. The fuel gauge is just lazy when it gets lower on fuel.

Video of the run can be seen a few posts back on page 2
Good info so far.

I have watched your first video perhaps 100 times now.

Very odd to "cut" like that. It appears you are already at wide open throttle at 3000 rpm, and as the engine sweeps past early 4000, I can't see that being a carb issue.
I would like to see another video. Could be your carb or ignition.

Myself, I hate MSD. I don't use it at all. A mate of mine says his car feels "like a 6 cylinder at times". I'm trying to convince him to go with an ICE ignition system.
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  #44 (permalink)  
Old 10-19-2021, 05:40 PM
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Originally Posted by Gaz64 View Post
Good info so far.

I have watched your first video perhaps 100 times now.

Very odd to "cut" like that. It appears you are already at wide open throttle at 3000 rpm, and as the engine sweeps past early 4000, I can't see that being a carb issue.
I would like to see another video. Could be your carb or ignition.

Myself, I hate MSD. I don't use it at all. A mate of mine says his car feels "like a 6 cylinder at times". I'm trying to convince him to go with an ICE ignition system.
Understood. Ill do my best to film another one in a few day. I can post a few more from the other day...but I just dont know if they will be any better
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  #45 (permalink)  
Old 10-19-2021, 05:50 PM
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Not sure how useful these will be...but this is what I have for now. You can definitely here it break up some...but its sluggish after 4k

https://youtu.be/rFpXzmJ2Y6s

https://youtu.be/IjtH5PuBt8I
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  #46 (permalink)  
Old 10-19-2021, 06:43 PM
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I would remove the line after your fuel filter before the carburetor, and perform a fuel volume test into a bucket. I would like to see at least 1 quart in 30 seconds.
If that's ok, then I would remove the needle and seats, (note the number of flats, so you can get them back in the ball park), and check for any fuel line debris that maybe restricting fuel flow into the bowls.
If that's ok, I would then pull the spark plugs and post some pics on here of them.
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Last edited by Gaz64; 10-20-2021 at 03:12 PM..
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Old 10-20-2021, 03:51 AM
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You need a K&N 66-3040 (or similar)unit. I've used this on several of my FE powered Cobra replicas (2-ERA's, 1 Contemporary, 1 Unique). If the air filter clearance is still a bit too close for your comfort, you can replace the 14X3" air filter with a 14X2.5" to 14X2.75" filter (there are four or five height incremental K&N filters available).

Now, with that said, before you spend any money, you need to see exactly what CFM worth of filter assembly you need to properly feed your engine.

Using the simple formula

A= effective filter area
CID=engine displacement
RPM=maximum RPM expected


Using the CFM formula of height X diameter x 6 x 3.14

Also keep in mind that the 14" extreme top flows 500cfm by itself.


Hope you find this helpful.

Sincerely,

Bill S.
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Last edited by mrmustang; 10-20-2021 at 03:53 AM..
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