car shuts off under braking!?!?!

[tfs2121]

whenever i brake hard my car will turn off... it seems to me like its not getting fuel or something... could this be caused by the float not being adjusted? it takes like 5 or 6 cranks befor it will start back up again too... humm any help... thanks...

[evlrs84]

I've battled the same problem on two different carbs on my car, the stock one and my 600 DP. I've got it where it won't die unless I really, really hit the brakes, but I don't have it 100% fixed yet. I've adjusted the floats, I've messed with the secondary butterflies, I've got no vacuum leaks, the brake booster is only about a year old and is not leaking, etc. etc. :grumble:

[85gt]

and i have the exact same problem on my carbed 85gt as well. it died on me twice on my way home from the store just now :-(. a knowledgeable mechanic friend mentioned that there may be an issue with the throtte kicker actuator or solenoid... evlrs84, with that 600DP you weren't using the throttle kicker assembly that bolts to the drivers side of the factory carb, were you?

[Zap's 85 GT]

I adjusted my rear float slightly lower than its supposed to be and havnt had a problem in years.

[tfs2121]

my throtte kicker wouldent fit on the new carb so i didnt put it on... by the "rear" float do you mean the sencondary bowl?

i wish i could fix it and all my other problums after the GT40 P swap...

[grtskydog]

Would those jet extensions help it? I would think it would keep pulling fuel even when it sloshes forward.

[evlgt85]

Not sure what you mean by throttle kicker assembly. I have no choke (the horn is still there, but the rest...ALL the rest is now gone) and no auto kick down as it's a stick, so if either of those are what you're talking about, then they don't apply to my car. There's no solenoids on my double pumper.

[Zap's 85 GT]

Yes I'm talking about setting the secondary floats a bit lower. The problem is that when you hit the brakes hard, the fuel is all forced up the metering block/plate and sometimes it spills out of the boosters and down into the venturis. Jet extentions would do nothing to prevent the problem. Some aftermarket intake manifolds tilt the carburator a few more degrees to the front(to align the air cleaner for better hood clearance) and it sometimes brings out that problem.

[85gt]

Zap, you are the man. I adjusted the rear float down to pretty much as far down as it would go, and it fixed all the issues with the car shutting off/bogging down when braking or cornering hard. No problem under hard acceleration (no leaning out when using the secondaries). Excellent suggestion. I would have never thought to adjust the secondaries lower. Anyone having the same problem should do just as Zap says!

[Ricky C]

When I had this problem on my car, I increased the fuel pressure a little, and adjusted the floats so that the fuel level is right at the bottom of the peek hole on the side of the float.

[Zap's 85 GT]

Awesome. At least I'm good for something. I remember I adjusted mine down a half a turn at a time until the problem went away.

I know its a trick that Pony Carbuerators uses on their reman'd holeys too.

[jeffascmclaren]

I run a Mighty Demon 650, and i have had to do the same as well, all though if i really stop it quick, there will be a 'lil sputter.