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Author Topic:   help me please
Whitelightning
Member
posted May 26, 2003 07:38 PM
ok I think this is a carb question. I run a stock q jet remanufactured from autozone and this is whats happening. I run a half mile track and before it seemed like when the engine got to 4600 rpm it would hang there and I could hit that on the straits half trottle and it be smooth or wide open trotle and it still turn about the same rpm> I chaged from a 5.20 final gear to a 5.80 and the car runs good now up to 5600 and does the same thing Its like that when seondaries comein it pulls hard and then quits and is not smooth at all once the secondaries come in for a second it just seems like possibly a gas starve or something in the secondaries and I dont know what to do I also relize I dont know if this makes since it hard to type what its doing. soon as the four barrel opens it some what smooth but then its not smooth at all it really just dont run to good at wide open trottle but runs ok 1/2 to 3/4 trottle any suggetions


KPLugnut
Member
posted May 26, 2003 09:55 PM
Firstly, your carb is not at all set up for oval track racing. Rebuilt OEM carbs are meant for street use and at best, mild performance, and only then will they do it by pure chance.
Quadrajets are quite finicky about fuel pressure (4-6lbs at idle is plenty), and are quite a bit more complicated to set up for good oval track performance.
The first thing you should look at is that you are not leaning out he motor extremely under WOT conditions. This causes what I think you're describing. Your problem may just be that the secondary feed tubes (one or more of them) have fallen out of their holes in the top of the carb. Remove the top of the carb and see if the 4 small brass tubes are still in place on the underside of the carb top. Make sure the inner 2 tubes are not clogged or that they don't have their tips bent or closed off.
The outer 2 tubes are more commonly what fall out tho. They are the fuel feed tubes.
OK, next, make sure that your secondary air flap spring tension is not too stiff. It should be adjusted so that they open quickly but not so easily that they "bounce" back shut again.
Both primary jets,and primary and secondary metering rods need to be altered for oval track use on a race motor, too.
And the power piston (where the primary rods attach) needs to be set up so it's not sticking and has the right tension spring under it for your race motor.

In a nutshell, should the actual cause of your problems be in the quadrajet, there's many things that can be doing it to ya.

I hope some of this helps...

KPLugnut


chickasaw kid
Member
posted May 28, 2003 11:33 PM
if the rules let you run another kind of carb take that one off put it down on a level hard surface (concrete works well). find you a real big hammer bust it all to pieces. pick up the pieces throw them away. then go buy a holley. if you are bound by rules good luck with the q-jet.


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