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Topic: un baffled gas tank in a cougar?causing bucking? (Read 1295 times) previous topic - next topic

un baffled gas tank in a cougar?causing bucking?

just did 5.0 ho swap in my Gfs cougar added 4:10s .from a dead stop if you floor it the car launches hard and doesnt spin  but then she falls on her face (the car that is) jumps back up then falls back on her face than is fine. im thinking its te fuel in the tank  sloching cause that thing launches hard. only seems to do it from the dig not a roll.also doesnt appear to happen when i have a full tank either. i planned on beefing the fuel system up with a 255 pump and adjustable regulator any way should i install a fuel tank out of a mustang?is my cougars tank un baffled?

un baffled gas tank in a cougar?causing bucking?

Reply #1
The stock fuel pump is not really adequate for the HO swap,
also having  the correct sock on the pump is important .
Fox-less at the moment

un baffled gas tank in a cougar?causing bucking?

Reply #2
yeah figured that much.cars getting way too good gas mileage lol.more worried about the stock shifting aod in the car .ive built mustangs and dord diesels for the past 10 years. ive always loved the cougars different body style. im not sure about the pump thats  in there. it was my gfs dads car. it got a rod knock he gave it to her she limped it around for a good 6 months and when she finaly blew up i got to start moddin it.im thinking about making it a great sleeper what do you think? do people usualy sleep on your car?

un baffled gas tank in a cougar?causing bucking?

Reply #3
If I launch with less than half a tank in my car it pulls so hard that I get the fuel slosh and stall/start up. I have a 155lph pump and the right sock. No tank baffles=stalling:hick:
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

un baffled gas tank in a cougar?causing bucking?

Reply #4
Stock Cougar/Tbird 5.0 pump = 65 LPH
5.0 HO Mustang pump = 88 LPH

Quote
having the correct sock on the pump is important .

Indeed.
I'm running a 255 LPH pump and  24 pound injectors with slightly elevated pressure.
Zero Issues.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

un baffled gas tank in a cougar?causing bucking?

Reply #5
only time mine cuts out from fuel loss is when i'm SUPER low on gas, like about to run out, and get on it hard while making a left hand turn....
Currently Birdless but never Foxless

86 Mustang GT

un baffled gas tank in a cougar?causing bucking?

Reply #6
X2, my car is stock, but when you get down do about 2 gallons, any left hand turn will stall it out.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

un baffled gas tank in a cougar?causing bucking?

Reply #7
I can't remember when the Sport had less than half a tank.When the gauge shows half,I fill it up.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

un baffled gas tank in a cougar?causing bucking?

Reply #8
Quote from: vinnietbird;338808
I can't remember when the Sport had less than half a tank.When the gauge shows half,I fill it up.


that's a good way to prevent it lol

un baffled gas tank in a cougar?causing bucking?

Reply #9
Quote from: vinnietbird;338808
I can't remember when the Sport had less than half a tank.When the gauge shows half,I fill it up.


wish i could do that......

get paid on monday, fill it up, and pray.....  :hick:
Currently Birdless but never Foxless

86 Mustang GT

un baffled gas tank in a cougar?causing bucking?

Reply #10
Mine has never had the full-throttle stalling/bucking/fuel surge, BUT...

When I had the stock SO fuel pump in, it ran rough, idled poorly, and seemed like it was down on power. I swapped in a walbro 255 and it made 'er feel like I put a blower on it. I did this after the car refused to start with a 1/2 tank of gas, and there was very little fuel pressure.

The difference was amazing. Idling in second gear, on pavement, drop the hammer and watch it get sideways in a big cloud of tire smoke.

255 is probably overkill for a stock HO, but I've got plans, and it was 20 shipped from a guy on the corral.

You need a better pump for real. :D
'84 Mustang
'98 Explorer 5.0
'03 Focus, dropped a valve seat. yay. freakin' split port engines...
'06 Explorer EB 4.6

un baffled gas tank in a cougar?causing bucking?

Reply #11
With anything less than a 1/2 tank mine will fall on it's face on launch...