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Hesitation ?? #1736726 01/23/15 03:12 AM 01/23/15 03:12 AM
Joined: Nov 2004 Posts: 3,517 pacific northwest S Stroker Scamp OP master
Stroker Scamp OP master S Joined: Nov 2004 Posts: 3,517 pacific northwest	Can an ignition issue cause the motor to stall or hesitate on a rapid full throttle whack? Reason I ask is I have tried 3 different carbs on the same motor (stockish 340)same results. The new carb is a 750 DP, been tuning it and its getting better but I think some thing else may be the culprit footbrake N/A SB 408 Scamp 10.10 @ 132 street/strip 73 Duster 340 street strip 12.79 @ 105

Re: Hesitation ?? [Re: Stroker Scamp] #1736727 01/23/15 03:15 AM 01/23/15 03:15 AM
Joined: Sep 2004 Posts: 6,906 IL, Aurora A ademon master
ademon master A Joined: Sep 2004 Posts: 6,906 IL, Aurora	could be as the cyl psi quickly rise, check to make sure your pickup to reluctor gap is at.008,

Re: Hesitation ?? [Re: Stroker Scamp] #1736728 01/23/15 04:58 AM 01/23/15 04:58 AM
Joined: Aug 2003 Posts: 43,129 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,129 Bend,OR USA	Is the vacume advance hooked up? If so try disconnecting it and see if that helps or not Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: Hesitation ?? [Re: Stroker Scamp] #1736729 01/23/15 12:07 PM 01/23/15 12:07 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	You make sure that the timing is set right first... then start on the carb.. make sure the pump arm and pump start a shot when you move the throttle.. then its how much

Re: Hesitation ?? [Re: Cab_Burge] #1736730 01/23/15 01:01 PM 01/23/15 01:01 PM
Joined: Oct 2003 Posts: 7,506 Az Crizila master
Crizila master Joined: Oct 2003 Posts: 7,506 Az	Quote: Is the vacume advance hooked up? If so try disconnecting it and see if that helps or not - after 3 carbs, it's time to start looking at something else. Ignition timing would be a good next step. I have several distributors for sale - - - ok, just kidding. Fastest 300

Re: Hesitation ?? [Re: Crizila] #1736731 01/23/15 02:25 PM 01/23/15 02:25 PM
Joined: Jan 2003 Posts: 32,394 Q Quicktree I Win
Quicktree I Win Q Joined: Jan 2003 Posts: 32,394	you could put 10 carbs, if the pump shot is not right it will do the same thing. timing should be set and right before you adjust the carb.

Re: Hesitation ?? [Re: Stroker Scamp] #1736732 01/23/15 09:13 PM 01/23/15 09:13 PM
Joined: Nov 2003 Posts: 3,426 Dandridge TN D Dabee master
Dabee master D Joined: Nov 2003 Posts: 3,426 Dandridge TN	I had the same problem with the 511 in my 69 Bee. I checked/tried everything and the hesitation was still always there. It was driving me nuts. Then I found a station near the house that sold 100% 93 octane gas. I started using that instead of the 10% ethanol crap and the hesitation went a way. May not solve your problem, but it is worth a try if you have access to 100% 92 or 93 octane.

Re: Hesitation ?? [Re: Quicktree] #1736733 01/23/15 09:53 PM 01/23/15 09:53 PM
Joined: Oct 2003 Posts: 7,506 Az Crizila master
Crizila master Joined: Oct 2003 Posts: 7,506 Az	Quote: you could put 10 carbs, if the pump shot is not right it will do the same thing. timing should be set and right before you adjust the carb. I went with the odds! 10 Carbs with focked up pump shots would be - rare. Fastest 300

Re: Hesitation ?? [Re: Crizila] #1736734 01/24/15 05:45 AM 01/24/15 05:45 AM
Joined: Jan 2003 Posts: 32,394 Q Quicktree I Win
Quicktree I Win Q Joined: Jan 2003 Posts: 32,394	Quote: Quote: you could put 10 carbs, if the pump shot is not right it will do the same thing. timing should be set and right before you adjust the carb. I went with the odds! 10 Carbs with focked up pump shots would be - rare. sure you did, the chances of any carb being right the first time for any given combo unless it's specifically set up for it are slim I would think.

Re: Hesitation ?? [Re: Quicktree] #1736735 01/24/15 01:00 PM 01/24/15 01:00 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Quote: Quote: Quote: you could put 10 carbs, if the pump shot is not right it will do the same thing. timing should be set and right before you adjust the carb. I went with the odds! 10 Carbs with focked up pump shots would be - rare. sure you did, the chances of any carb being right the first time for any given combo unless it's specifically set up for it are slim I would think. Maybe in days of old AND some new where the brilliant whackos added more holes than swiss cheese and you musta missed the last thank you post. Bolted it on and raced NO adjustments...............Doesn`t happen everyday but when set up PROPERLY they can be real close. Too bad you didn`t send me yours so you could experience the same things....... 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: Hesitation ?? [Re: Thumperdart] #1736736 01/24/15 01:21 PM 01/24/15 01:21 PM
Joined: Jan 2003 Posts: 32,394 Q Quicktree I Win
Quicktree I Win Q Joined: Jan 2003 Posts: 32,394	Quote: Quote: Quote: Quote: you could put 10 carbs, if the pump shot is not right it will do the same thing. timing should be set and right before you adjust the carb. I went with the odds! 10 Carbs with focked up pump shots would be - rare. sure you did, the chances of any carb being right the first time for any given combo unless it's specifically set up for it are slim I would think. Maybe in days of old AND some new where the brilliant whackos added more holes than swiss cheese and you musta missed the last thank you post. Bolted it on and raced NO adjustments...............Doesn`t happen everyday but when set up PROPERLY they can be real close. Too bad you didn`t send me yours so you could experience the same things....... lol I don't have any problems with mine. it runs great and repeats

Re: Hesitation ?? [Re: Quicktree] #1736737 01/24/15 01:26 PM 01/24/15 01:26 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	That`s what most "Bracket racers" say............... 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: Hesitation ?? [Re: Stroker Scamp] #1736738 01/24/15 07:12 PM 01/24/15 07:12 PM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	If your running a power valve with too low a number will do that. I like them 1.5 under in gear idle vacuum. Seems now days where carbs used to come with 6.5's or higher they are 4.5 helps take tunning for dummies with a cam out of equation.

Re: Hesitation ?? [Re: Dodgem] #1736739 01/24/15 07:33 PM 01/24/15 07:33 PM
Joined: Nov 2004 Posts: 3,517 pacific northwest S Stroker Scamp OP master
Stroker Scamp OP master S Joined: Nov 2004 Posts: 3,517 pacific northwest	Thanks for all the ideas, finally stopped raining so I will tweak it a bit and let you know. footbrake N/A SB 408 Scamp 10.10 @ 132 street/strip 73 Duster 340 street strip 12.79 @ 105

Re: Hesitation ?? [Re: Dodgem] #1736740 01/24/15 08:01 PM 01/24/15 08:01 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Quote: If your running a power valve with too low a number will do that. I like them 1.5 under in gear idle vacuum. Seems now days where carbs used to come with 6.5's or higher they are 4.5 helps take tunning for dummies with a cam out of equation. NEGATIVE..........Doesn`t work that way unless you`re WAY into the transition on the primaries cos when the idle`s correct you can remove the jets w/no change. As far as p/v sizing, take a drive at a steady rate or slight load, look at that # then maybe drop down 1-2 for power enrichment.......... 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: Hesitation ?? [Re: Thumperdart] #1736741 01/24/15 08:07 PM 01/24/15 08:07 PM
Joined: Jan 2003 Posts: 32,394 Q Quicktree I Win
Quicktree I Win Q Joined: Jan 2003 Posts: 32,394	Quote: Quote: If your running a power valve with too low a number will do that. I like them 1.5 under in gear idle vacuum. Seems now days where carbs used to come with 6.5's or higher they are 4.5 helps take tunning for dummies with a cam out of equation. NEGATIVE..........Doesn`t work that way unless you`re WAY into the transition on the primaries cos when the idle`s correct you can remove the jets w/no change. As far as p/v sizing, take a drive at a steady rate or slight load, look at that # then maybe drop down 1-2 for power enrichment.......... negative that method is for street driving, doesn't work well for a race car. it can and will cause a hesitation. the 1-1.5 HG below idle in gear works best for any race car I have seen. I usually don't run PV's don't need them

Re: Hesitation ?? [Re: Quicktree] #1736742 01/26/15 02:45 AM 01/26/15 02:45 AM
Joined: Nov 2004 Posts: 3,517 pacific northwest S Stroker Scamp OP master
Stroker Scamp OP master S Joined: Nov 2004 Posts: 3,517 pacific northwest	Well didn't have much time today, but took the Duster for a drive still have the full throttle whack hesitation and I have what sounds like a lean miss fire at 2500 RPM pretty sure this is all not carb related. Not sure where to look next except ignition footbrake N/A SB 408 Scamp 10.10 @ 132 street/strip 73 Duster 340 street strip 12.79 @ 105

Re: Hesitation ?? [Re: Stroker Scamp] #1736743 01/26/15 08:26 AM 01/26/15 08:26 AM
Joined: Jan 2003 Posts: 32,394 Q Quicktree I Win
Quicktree I Win Q Joined: Jan 2003 Posts: 32,394	just for the heck of it change the squirters. go up one size and see if that helps any. I assume you have tried messing with the cams and have that part set up right? put a brown cam on them. you may very well have other problems but make 1 change at a time.

Re: Hesitation ?? [Re: Stroker Scamp] #1736744 01/26/15 01:27 PM 01/26/15 01:27 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Going through this on a guys car and the FIRST thing I suggested was a crank. comp. test and sure enuff he had several low cyls. for whatever reasons cos he hasn`t called back yet. I`d pull all of the plugs and see how they look then check plug wires etc. 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: Hesitation ?? [Re: Thumperdart] #1736745 01/26/15 08:50 PM 01/26/15 08:50 PM
Joined: Oct 2003 Posts: 339 Wisconsin B BIGS enthusiast
BIGS enthusiast B Joined: Oct 2003 Posts: 339 Wisconsin	Hey Stroker, what is your base/initial timing at idle and how quick are you getting your total in......this is the first place to start.....Jesse Jesse & Lynn BIGS Performance Products Building Street/Strip Carburetors since 1974 www.bigsperformance.com

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