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Author Topic:   stalling
roche314
Dirt Roller

Total posts: 18
posted July 18, 2005 07:19 PM  
72 buick skylark with Chevy 350 motor.

The car ran decent in the heat races, then about 10 laps into the main, when I would get back on the gas towards the end of the corners the car would stall, then it would stumble a little and hook up again about 1/4 of the way down the straights.

Wiring to distributor looks fine, it is a brand new mallory.

I did just put in some new flowmasters, they are right under the driver & passenger seats. They do end up being about 5 inches from the frame and fuel lines. Do you think this is close enough to start getting vapor lock?

racer17j
Dirt Forum Champ
Total posts: 5390
posted July 18, 2005 08:12 PM  
thanks, I don't see anywhere that the fuel lines could be getting pinched. All the rubber fuel lines aren't near anything that moves and all the steel lines are still intact.

sc1 racing
Dirt Freak

Total posts: 419
posted July 19, 2005 09:01 AM  
could it be floating the valves? how many r's is it turning when it does this? if it is stock more than likely it will float between 4,500-5,200 rpm..depending on the shap of the valve train..

roche314
Dirt Roller

Total posts: 18
posted July 19, 2005 09:25 AM  
I don't think it is floating the valves. I am running the car in 2nd, and it is staying under 4000. But it is a stock motor.

sc1 racing
Dirt Freak

Total posts: 419
posted July 19, 2005 10:25 AM  
if it is floating the valve the engine will fall on its face, then when rpm levels out it will come back to life..dont know if you have ever experianced going to fast in a car that shuts down at a certain speed but it feels the same way..

roche314
Dirt Roller

Total posts: 18
posted July 19, 2005 10:31 AM  
If it was floating the valves wouldn't that have been happening from the start, not 10 laps into the race?

hotrodenford
Dirt Full Roller

Total posts: 60
posted July 19, 2005 11:42 AM  
Check the tube inside your fuelcell. Make shure the end is not sucking to the side. check the float level in the carb. When going through the turn fuel slosh could be flooding it out. Check the fuel lines around the exhaust manifolds and buy the engine. If any of the lines touch anything hot or get too close it could boil the gas. What is your timing set at? Are you running vacume advance? how fast does the mech. advance ramp up? or is the timing locked?

I dought it is valve float being the problem is coming out of the corner not at the end of the strait.

roche314
Dirt Roller

Total posts: 18
posted July 19, 2005 11:52 AM  
The tubes in the fuel cell are fine.
I need to check the float level in carb.
Timing is at 30 degrees full mechanical advance and it ramps up pretty quickly. I am using vacuum advance.
The fuel lines do run pretty close to the mufflers, about 5 inches away.

sc1 racing
Dirt Freak

Total posts: 419
posted July 19, 2005 11:52 AM  
yes i read that wrong i thought it was hapening off the turn down the straights..

sorry about that. could definatly be your float

roche314
Dirt Roller

Total posts: 18
posted August 04, 2005 08:39 AM  
I rerouted the fuel lines through the car and the problem went away. So it was most likely vapor lock from the fuel lines being so close to the mufflers.

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