tailpipe clearance to gas tank

What is a good rule of thumb as far as clearance from exhaust pipe to gas
tank. What are so experiences pro or con.

 

Steel or Poly Tank?

 

the farther the better, but i would say not less than 4inches , the main thing is not to heat the fuel in the tank, and sooner or later the tank might leak avoid dripping on pipe.

 

When distance from the tank was a problem, I've wrapped the tailpipe with that header wrap material. Might not be pretty, but it works.

 

3 to 4 inches. HRP

 

Come on 4 inches ?, I run them as close as an inch on a steel tank. never had a problem. Like 2 inches on a poly tank if possible.

 

I like to be able to get two fingers on a steel tank.
As much as possible on a Polly tank.

If I can't get that , I try for a sleeve of 3" with air gap over the tailpipe.
Like a 3" pipe over a 2 or 2.25 tailpipes.

 

As long as they don't bang together. Lots of factory exhaust systems are no more than an inch or 2 away.

The exhaust isn't very hot by the time it gets to the back of the car. Not as hot as the front anyway.

I only heard of 1 car that caught fire from exhaust heat on the gas tank. That was an old K car with a split seam on the muffler and the exhaust blasting straight at the tank for over an hour as the driver drove on the interstate on a hot summer day.

 

Unless your aiming the exhaust at the tank, the width of 2 fingers is plenty, regardless of what the tank is made out of. Many a Dodge 70s-90s vans ran around with the tail pipe 1" away from the poly tank for many years. Gene

 

I'm in the 2 finger crowd. As long as it is not touching, the heat is only transmitted by radiation. There is no way to get 4" of clearance under a deuce gas tank and not have it look lousy. IMHO

 

I agree..I run about 1-1/2 to two inches clearance to my poly tank...no problem at all. I originally built heat shields over that section of the tailpipes but found that they were not needed. BUT I do live in Maine and I'm never stuck in traffic, so when my car is running its usually moving. Might be different if I had to sit at idle for long periods.

 

I just installed a set of smithys mufflers on my 59 fairlane. On the drivers side one muffler runs right under the gas tank vent tube, they are almost 3 inches apart and i put a piece of 18 gage sheemetal between them to act as a heat shield. Do you guys think it will be ok? Your thoughts please

 

Sounds good to me!

 

Make a heat shield and place around exhaust pipe it does keep tank cooler .