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StompNDump 06-23-2020 11:17 AM

RPM drop while on Stop
 
Running an APD Max Speed carb with built in stop and ive noticed on my logger that the car will drop roughly 100 to 120 RPMs while on the stop. Is this normal or has anyone else had this issue.

J&S Racing 06-23-2020 12:04 PM

Re: RPM drop while on Stop
 
Max speed a great piece but very finicky imo..

Are you running a 02?

StompNDump 06-23-2020 12:40 PM

Re: RPM drop while on Stop
 
Not running an 02 just yet, have a set up coming.

Lenny5160 06-23-2020 12:51 PM

Re: RPM drop while on Stop
 
Does the RPM drop coincide with the shift?

StompNDump 06-23-2020 12:55 PM

Re: RPM drop while on Stop
 
It doesn't appear to coincide with the shift.

J&S Racing 06-23-2020 01:18 PM

Re: RPM drop while on Stop
 
Quote:

Originally Posted by StompNDump (Post 617244)
Not running an 02 just yet, have a set up coming.

02 is a absolute must for this carb!!! Make sure you place them 12ish” off the head.

More than likely its your front jets.

StompNDump 06-23-2020 02:16 PM

Re: RPM drop while on Stop
 
Whats your recommendation of what I should try with the front jets?

J&S Racing 06-23-2020 04:50 PM

Re: RPM drop while on Stop
 
Quote:

Originally Posted by StompNDump (Post 617254)
Whats your recommendation of what I should try with the front jets?

I don’t have my log book handy and I only made a few hits last year so I Just can’t remember what way you gonna go for the loss of RPM. Really need to see what the A/F is doing on the stop.

Until you get the O2s I’d play it safe and start by giving it more fuel and see what it does. If it gets worse go down a few sizes from what’s in there now.

For the most part the front jets control what its doing on the stop then you tune the restrictors behind the power valve and rear jets for down track.

StompNDump 06-23-2020 04:52 PM

Re: RPM drop while on Stop
 
Sent you a PM

sully3358 06-24-2020 01:02 PM

Re: RPM drop while on Stop
 
need to go smaller on front jet

what is your current setup? main jets front and rear and restrictor sizing in front?


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