Author Topic: six pack runs like crap  (Read 5872 times)

Offline Chryco Psycho

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Re: six pack runs like crap
« Reply #15 on: November 25, 2007 - 03:51:01 PM »
I would advance the timing & disconnect the vacuum advance this should clean up the low- midrange
 the heavier springs will fix the bog with the secondary opening , just change 1 spring at a time as it is a combination of both springs so changing 1 at a time will aloow you to sneak up on the correct load to open the seconadries smoothly

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Offline cudabob496

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Re: six pack runs like crap
« Reply #16 on: November 25, 2007 - 04:08:27 PM »
Possible timing curve issue? Also from my service manual, for poor acceleration, manifold heat valve sticking, accelerator pump piston leather too hard, worn, or lose on stem; faulty accel pump discharge ball, faulty accel pump inlet check ball, incorrect fuel or float level, worn accel pump and throttle linkage, or incorrect pump setting.

Other possibilities, cracked body, faulty body gaskets, high float level, worn needle valve and seat, excessive fuel pump pressure, leaking float.
« Last Edit: November 25, 2007 - 08:05:24 PM by cudabob496 »
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline zimcuda

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Re: six pack runs like crap
« Reply #17 on: November 25, 2007 - 09:57:35 PM »
Well, if I have some time after work tomorrow I will re-check float levels, secondary idle mixes and look at the plugs.  If that checks out I'll try moving the timing again.  I've never used the vacuum advance and the new dist. doesn't have one, so I'm good there.  If nothing helps, I think I'll try the #68 jets just to see if anything changes for better or worse.  Otherwise, it might be time to park it for the winter and try again in the spring.  I wonder if I've been good enough for Santa to leave an EFI under the tree?  Doubt it!  Besides, my brain won't rest until I figure this darn thing out and put it to rest.  Anyone try using Edelbrocks air fuel ratio monitor?  That way I could see exactly what the mix is doing and when in relation to the problem.  Also looks like it would fit real nice in the empty area under the wiper switch.

Offline zimcuda

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Re: six pack runs like crap
« Reply #18 on: November 27, 2007 - 10:19:23 PM »
Finally found it! :bananasmi After double checking everything with the carbs and making some changes, nothing helped, so I started moving the timing.  That didn't really help either, but while checking it, found the advance wasn't full in until 3500.  Swapped lighter springs into the pertronix unit I installed this summer to get the timing in quicker and it ran like a dream.  Never would have believed getting the timing in 1000rpm quicker would make such a drastic improvement, but it did.  Went from barely driveable to dosed on designer steroids.  The 12/36 I settled on was fine, easy starts, good idle and great top end.  Just needed it in sooner.  Thanks all, for all the input.  It really helped get me on the right path to success. 

Also, the promax metering block and jet plates really do work great and make tuning so much better to dial in. 

Offline Chryco Psycho

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Re: six pack runs like crap
« Reply #19 on: November 28, 2007 - 03:03:09 AM »
 :2thumbs:

Challenger - You`ll wish You Hadn`t