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3rd gear 5500 rpm cutout

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my car cuts out at 5500 rpm in 3rd

it will stall/die, throttle does nothing, and the rpm guage will usually drop

I'm thinking it's ignition, it'll continue to cut out for a few minutes after I push it real hard

does not seem to cut out in 1st/2nd runup's, only in 3rd where it's at 5000+ rpm for a while

I cant tell if it's ignition, or fuel, ideas how to test?

I have manual switches for both ignition and fuel, flipping them on/off does nothing

my fuel filter is right under the hood so a 1 min replace, doign that at lunch

I have resistor plugs & wires, couldnt get non resistor plugs, could that cause this?

I'm going megasquirt this spring, so I just need to last till then

car has a k300 cam, 32/36 webber, korman stage 2 engine, header/piston/timing the engine was built in 91 and has major blowby

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You said it does it when you hold it past 5K for while. That's kind of a lot of revs to hold a tired engine at in 3rd anyway.

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yeah, but it's not mechanical

I'm thinking it's electrical, it dies, total death until the rpm's drop down to 500

I'm not sure what it could be, I'm sure it'll resolve itself when I switch to the megasquirt, but until then it's kinda scary

it has a red coil pictured here

DSC_1156.JPG

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where can you even get w7dc's?

I have wr7dc's in it now, bav does not even sell the w7dc's only the resistor plugs

I checked the wires, they have resistors in them

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Probably do not have them at AutoZone or the like, but might order them for you. But I doubt that would be your problem anyway. Hopefully somebody else with a better clue will chime in on this later today.

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That is a terrible place to mount your ignition coil...near the heater box....anytime that car gets wet, water will fall directly onto your coil through the hood slots and that is no good...you may want start researching your cut out problem by first moving the coil back into the engine compartent where it belongs...then go from there in researching the problem...

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an ignition cutout would either not come back,

or come back quicker.

I suspect that you're not getting quie enough fuel volume, and on that long haul up to 5K, you eventually empty the float bowl.

As it spools down, the pump starts to refill the bowl, and you've got gas by the time you hit idle.

Easy to test- find someplace where you can wind it out, then as SOON as it dies, switch off, clutch in, and coast to the side of the road.

Pull the carb top cover, and check the fuel level in the float bowl.

fwiw,

t

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pretty sure it's the fuel pump

I replaced the filter, still same symptoms, if not worse

I tested it today, it'll pump really really good, till I put some back pressure on it, then it's very weak

and it takes a while for it to ramp back up again, seems shot

anybody got any recommendations for a cheap electric pump for a 32/36 webber?

cheaper is better it'll only be on the car a few months, going EFI

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You could go with a pre pump from a ..... 320i? and then put your new electric efi pump on top of that one when you go MS. This would get you a low psi for now and then a good solid pre pump for later. Or you could just drive it gently till you go efi and use a 318is in tank efi pump later.

John

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the new summit store down the street has the carter everyone seems to like for 65 $

just gonna get that one

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put in a carter 4070, these things are huge

it ran better, but still cut out at 5500rpm, but it only stalled for a second, unlike the old pump that would stall out for 30 seconds

is there a screen on the pickup in the tank? Guess the new high psi fuel lines are going to be installed sooner than expected

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there was a filter on the fuel tank pickup

it was plugged, all the fuel had to enter via a tiny little hole in the side of the pickup

I removed the filter, I have a filter up in front of the carter, will see tomorrow if it's fixed now

and I did test it, drove it up till it stalled, flipped off the fuel pump and it wouldnt restart until I flipped the fuel pump on

anyone know how many feet of fuel line these require? I'm going to run a new pair of lines for the FI next week

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one other thing that's bothered me

when it dies the rpm guage drops to zero

even with the clutch out, and in gear, is that normal? I figured it would still read the rpm while it was stalling

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