surging going down track

what are some causes of engine surging going down track,leaves line good and hard,motor surges after 60 ft, chevy with 14 degree heads and 1471 helix,have no race pack!

 

Is this a "down" surge (engine laying down) or an "up" surge (engine running away from the clutch)? What type of gearing (rear end & trans) do you have?
DC

 

its a laying down type,power picks up falls flate ,surges like that all the way down track after the 60,rear gear is a 389,180 gear 2spd glide,thanks for any help

 

I'd check the barrel valve spool is setup correctly

we had a similar problem with our injected car, turned out the spool had turned on the shaft so at full throttle wasn't supplying enough fuel

 

What fuel tank do you have? I had a 7 gal tank from Time McAmis and it would suck a hole in the fuel untill I installed a tube in the tank and it fixed it. Well McAmis knew this when he sold the 7 gal tanks but did not tell anyone and then came up with a $350.00 fix for it. Yes this tube. He said the 10 gal thanks have had not issues. Check the tank or any lines if you have canged any of that.

 

Can you elaborate about this. Trying to visualize what the cause and solution were. Building a tank right now, and don't want to make the same
kind of mistake.

While on the topic, is it common to put baffles inside a custom tank, or do most just leave the tank volume wide open and suck from the middle of the rear floor/wall junction via a welded tube? 1.5" outlet tube in our case, 12 gallons, somewhat square in shape, two returns, front mounted. Max pump draw roughly 30gpm, two -12 vents.

Wondering whether baffles might help, and whether any shaping around the outlet might help?

 

SBC or BBC? Dragster or ? Blown Vette may be on to something w/ the fuel tank. My first guess would be the engine is too lean (usually if too fat the "lay down" comes later in the run (unless its drowning in fuel). I had the latter happin w/ our first run testing a AA/DA (1979) and had a new pump. The car "blubbered its way" down the track. A .015 leaner main jet picked up a full second. Since my info is 25+ years old, I can't make a good guess on the gearing. In 1980 we ran a AA/DA geared high (tranny wise) for the day (4.56 w/ Lenco 3 speed 188/ 131/ 1), but at best we had 1400 HP in a 1800lb car. I am not familar enough w/ a powerglide RE if something wrong there is pulling the engine down.
DC

 

tank theory makes sense, what size vent has your tank got? possible it can't bring in enough air to replace the volume of fuel being taken out

 

http://store.trackerdesigns.com/Mer...K&Category_Code=Fuel_Systems&Store_Code=TMRCI
The link above shows the complete kit. I only used the tube all of the other stuff is standard. The tube is easy to make.

 

if it was a lean cond,wouldnt it throw flames or blow the burst panel out?

 

Alot Of Guys Use A Rubber Hose To Coupling Hard Line From Fuel Tank To Pump.i've Heard Of Those Rubber Hoses Collapsing Shut,the Hose On Our Car Is Just Enough To Join Line To Pump-3"or So.i Know Some Guys Used To Make A Coil From Heavy Wire And Slide That In Hose So It Wouldnt Collapse,but Thats Old School Stuff.

 

Blown Vette, I Had The Same Tank As You, Ran For Years And Never Had A Problem Until I Put A Fuel Management System. Sucked A Hole Then Burned A Hole Or Two. Mcamis Tole Me When I Bought The Tank To Add The Line But I Thought It Would Be Fine.

 

I'm having a hard time picturing why or how the pump would suck a "hole" thru the fuel without that tube in place? Could someone please explain?

 

They Told Me With This Short Tank A Strong Pump Will Suck A Vortex In The Fuel Tank,like When A Bathtub Drains. I Noticed After I Opened A .080 High Speed At The Hit, A .070 At 6 Tenths, With A .075
Pump Loop. Fuel Pressure Never Picked Up Over 65 Lbs, Fuel Flow Was Around 8 Going In The Motor. Lost Around 5 Gpm.burnt Up In High Gear
It Was The First And Last Time I Opened So Big An Orifice So Fast
The Tube Mcamis Makes Goes In The Tank Around 4 Inches And Splits The Fuel Pickup To The Bottom, Both Sides Of The Tube, With The End Capped Off-THIS IS THE SAME TANK WIZARD SELLS ALSO, 7 GALLON POLY