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  #1  
Old 12-15-2000, 12:33 PM
ChrisA ChrisA is offline
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Join Date: Feb 1999
Location: Troutdale Or USA
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Completely Built up 400 in my Sattelsite, with 9:1 compression, 750 edelbrock, ported heads, gasketmatched, edelbrock dual plane performer intake, hookers, msd 6al with blaster 2 coil, m.p. race distributor recurved with 36 degrees advance, holley mechanical fuel pump, gauge and regulator set to 5.5psi, rejetted the carb, accell plugs, gapped to .050 for msd, KnN filter, Hughes engine kit and Cam,

Ok so Im in my driveway with car warm, rev the engine and is smooth and sounds good,

but im going 30 or 40 on the street in 2nd or third gear and I floor it or smash into it, it sounds like the engine completely dies, car slows down for a half second, then the engine picks up like it never happened and away I go. WHY???????????
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Old 12-15-2000, 01:55 PM
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Frank Frank is offline
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Chris, the car sounds cool, and you've done a lot of mods to it, so it will probably be difficult to say "Your problem is..." But, if your only experiencing the problem under load, that's a classic sign of a clogged, or defective gas filter. It's the place to start, and it's cheap. If that's not the problem, then it will probably go to one, or a combination of the modifications. Then it will be time for some "real mechanicin'". Let us know if this first step helps. By the way, what size and type of carb have you chosen?
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Old 12-15-2000, 08:03 PM
451Mopar 451Mopar is offline
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It sounds like a fuel problem.
If you roll into the gas and not stomp it and it dosen't do this, then I would check the accelerator pump circuit. If it does it all the time, then I would check your fuel delevery volume and pressure, plus check float levels.
Also, make sure to check for old cracked or loose gas line connections, expecially the rubber hose that connect the fuel tank to the gas line.

There is a possability the carb is way too rich, but for it to act this bad while running rich, the exhaust will probbly smoke when you punch the gas.
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Old 12-15-2000, 09:01 PM
COLORMECLONE COLORMECLONE is offline
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sounds to me like the secondary air valve is opening too quickly.
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Old 12-17-2000, 02:07 AM
HOLESHOT HOLESHOT is offline
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Cool

CLOSE THE GAP ON THE PLUGS DOWN TO .038 MAX AND UP THE FUEL PRESSURE TO 6.5-7.0 AND I BET THE MISS GOES AWAY UNLESS THE FILTER IS RESTRICTED.UNDER LOAD THE GAP IS SEEN AS TOO MUCH GAP TO JUMP AS THE PRESSURE STRESS IS INCREASED AS COMPRESSION /RPM INCREASES.
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Old 12-17-2000, 03:13 PM
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Leigh Leigh is offline
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Air valve, pump shot, slow curve. All or a combination.
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  #7  
Old 12-21-2000, 03:34 AM
ChrisA ChrisA is offline
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Ok, messed around with the acceleration pump stroke, upped the fuel pressure to 7 psi, problem still there,

Remeber the carb is 750 edelbrock, the performance 750 not the economy one,

Should I try changing to a different plug? when i took it too a shop a while back they recommended these accell "header plugs" because they said they were shorting against my hookers? What do you guys think? Thanks!
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  #8  
Old 12-21-2000, 04:20 AM
rat roaster rat roaster is offline
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The secondary air valve is probably opening to fast(in the carb) causing a big gulp of air ,slowing down your annular air speed in the carb and making the engine bogg . Borrow a holley carb a stock 750 vacume secondary or a small double pumper and try it before you go buying new parts.If the holley works try tuning your edelbrock go to their web site and get into performer series carbs and tuning tips. http://www.edelbrock.com/automotive/index.html
Whats it like if you hammer it idleing off the lights ? Does it sometimes backfire when you hammer it at low rpm ?
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