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throttle hesitation


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#21 racerx

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Posted 16 April 2018 - 07:12 AM

What kind of timing light do you have? Does it have a dial, where degrees can be adjusted, usually the dial is located at the back of light. Or do you have a digital timing light? 2nd, do you know where your timing tab or pointer is at? 3rd, do you know where ur tdc or zero degrees is at?

#22 Stoffregen Motorsports

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Posted 16 April 2018 - 07:17 AM


 

a weber DGV just bought  on a A14 might be a little big for this motor but manageable

Absolutely not. The A12 I had in my 320 would actually pull the secondaries open almost by itself. It was weird to feel that under foot.

 

One thing to consider is the age of the Weber. About 12-15 years ago Weber did a redesign of the main fuel circuits. In the older style carb, the primary and secondary shared a fuel circuit, which meant that when you romped on the throttle and the secondaries opened, it would take a second for the secondary fuel circuit to react to the sudden fuel demands. The newer style carb (marked with a 5A) has split individual circuits, alleviating this problem and eliminating the lag.



#23 Stoffregen Motorsports

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Posted 16 April 2018 - 07:23 AM

It is 30-35 degrees at idle. It is going to be primarily a race car but it will probably be driving itself to events.

 

Accelerator pump is one of the first things I thought of. My beetle was just having this problem and adjusting the accelerator pump fixed it right up. But on this weber there appears to be no way to adjust it. I've taken it apart and it looks fine inside.

 

racerx someone suggested  that I should use high altitude jets

It sounds like this is your first foray into racing. You've got a steep learning curve in front of you. First thing you need to learn is how to observe your car and recognize when there's a problem. The timing sounds like one of those problems.

 

The second thing you are going to need to learn is how to jet your carb. Every track is different, every day is different.



#24 Dirtyowlnumber4

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Posted 16 April 2018 - 10:27 AM

I have a digital timing light. I checked out the notch today, it is in the right place, the cylinder was at the top when it was, I marked it with spraypaint. 

 

You can barely see the timing mark here, but its there. I guess my timing light must be broken. The cars running good, I'll take it down to the shop and have them put their light on it.



#25 racerx

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Posted 16 April 2018 - 12:37 PM

Sounds like u also need valve adjustment...good to hear you got your timing figure out.