74 b body fuel tank, single vs dual exhaust - any difference?

[mschoo92]

Hey all,

I posted a similar thread in the exhaust section of this forum but I figure this section may get more responses as it is 74 specific.

I’m installing a dual exhaust on our 74 “roadrunner” clone. Car was originally a 318 auto, previous owner installed 440 4 speed. Exhaust they had on it was cobbled together, and I think I found out why...

At the rear of the car, there is ample clearance on passenger side of fuel tank to mount the axle back portion of the exhaust. On drivers side there is no room. See photos:

my questions are:

1. Was there a different tank/mounting in 74 for a single exhaust vs dual exhaust?
2. Does the current tank mounting position appear correct versus what you have on your 74 b body car?

I tried loosening the straps to see if I could move the tank over but it didn’t seem like I could - I admit I didn’t fully take the tank down as it’s pretty full, I’d prefer to get some info before going that route but if I don’t I’ll be sure to post my findings here. My goal at this point is to just get the setup correct so that the pipes are in the correct locations and fits as designed.

thanks in advance.

-Michael

 

[moparvinson]

I think 74 only had the big square vapor tank on top of the gas tank. Will not give much room to move it side to side?

 

[Nacho-RT74]

The diff is the width to allow or not the left side exhaust.

Repro tanks ( CR21A ) are made based on the dual exhaust setup.


And no, can't be moved to the sides. Not even 71/73 which don't have the hump. It won't align with the filler tube provision if you try it.

 

[mschoo92]

The diff is the width to allow or not the left side exhaust.

Repro tanks ( CR21A ) are made based on the dual exhaust setup.


And no, can't be moved to the sides. Not even 71/73 which don't have the hump. It won't align with the filler tube provision if you try it.

thank you for the help! Not what I was hoping to hear, but much better to know what the issue is and how to address it.