[78w72]

Wow! Thats a pretty tight fit but glad it went in ok.
I agree 100% about those transverse mufflers, ok for factory correct cars, but even then its so close to the tank that it cant be good for heat to the tank. Add bigger tailpipes and it ends up like yours.. way too close IMO. Maybe consider some heat wrap tape on the tank & the pipes/back side of muffler, summit/jegs sels some stick on heat tape that work good, I have some small sections on the fuel lines that come closer than I like to the 3" tail pipes, there a couple inches between and the pipes have cooled a lot back there, but still creates a lot of heat. Ive always like real dual mufflers vs transverse, they flow better too.

[RAIIIJudge]

What about gently grinding back that seam?

[jhein]

OK, I realized that I'm way overthinking the placement of the access door. It just needs to be centered right to left and then placed as far forward as possible, right up against where the trunk floor angles up. So that's solved, now I don't need to mark it from below. We'll see how close it is to the muffler once it's all tightened up. Does anyone think the heat issue is something that needs to be addressed or doesn't really matter?

[JLMounce]

I think if you use a heat reflecting product in the back side of the tank you’ll be fine. I wouldn’t overthink that part too much.

[73ta]

I wrapped my transverse muffler with heat shield along with my fuel lines. It's very tight back there!

[HWYSTR455]

Yeah, that's going to superheat the gas, that's too close.

I agree, you're going to need to shield it somehow. Even though fuel is under high(er) psi and somewhat resilient to heat, that's before the system, and eth fuel has a low boiling point, it's going to impact the picking up of the fuel.

I saw this happen on a power tour, people caught in traffic, and the asphalt radiant heat would superheat the tank, and folks were sidelined.


.

[HWYSTR455]

Maybe even an air dam on the lower leading edge of the tank would help cool it.

Just thinking out loud...

.

[jhein]

I think I’ll get a bit more space when I tighten the straps. I’ll be working on it more tomorrow so we’ll see.

[jhein]

Originally Posted by HWYSTR455

Maybe even an air dam on the lower leading edge of the tank would help cool it.

Just thinking out loud...

.

That would be pretty cool, but it's beyond my skill level.

Separately, I will say that my driving habits for this car are pretty routine. I drive in the morning and here in my part of OR even in the summer when the highs are in the 90s+, when I'm diving it is usually in the 50s with continuous travel, no stopping. So there's lot's of convective cooling.

Now, I know it's not a great idea to build a car that can only tolerate a narrow range of conditions, I get that, but just saying.

[jhein]

OK, this is the most clearance I can get. It is an improvement. That is with the upper rear edge of tank hitting the stops that are on the floor pan of the trunk.



My carriage bolts are much longer than they need to be. Not a big deal on the right side but on the left side the tank is pushed up against it. I think I need to cut that bolt a bit. Also, there are some large spacers on the bolts that are limiting how much I can tighten the straps. I think those both need to go. You can see in the pictures that the straps aren't tight up against the tank along the whole length.





Another thought is that I could use some strips of rubber as spacers to drop the rear of the tank about an inch to clear the stops on the floor pan. That would give me a little more clearance from the muffler. Or, I could just go to a dual muffler exhaust and make this a lot easier. Although Formulajones seems to do these tanks systems with the transverse mufflers without difficulty, so maybe I'm just missing something.

Oh, and here's how my pump fittings worked out.

[Gator67]

Was the old fuel tank further away from the muffler? Just wondering why this is a problem now and not before. I apologize if you explained this already and I missed it. It looks like you have sufficient space…why not run it for a while to see if you run into issues?

[jhein]

Originally Posted by Gator67

Was the old fuel tank further away from the muffler? Just wondering why this is a problem now and not before. I apologize if you explained this already and I missed it. It looks like you have sufficient space…why not run it for a while to see if you run into issues?

I never really paid that close attention the previous setup since I didn't install it. But you're probably right that it was likely similar. I'm sure it will be fine. I just need to get the straps and bolts figured out so I can move on to the rest of it.

[73ta]

I went hard lines from the tank tucked into the seam of the tank insulated and wrapped the muffler with heat shield. No issues, but I run an in tank pump with a return reg via 1/2" lines which circulates the fuel and probably helps also.

[Gator67]

Originally Posted by 73ta

I went hard lines from the tank tucked into the seam of the tank insulated and wrapped the muffler with heat shield. No issues, but I run an in tank pump with a return reg via 1/2" lines which circulates the fuel and probably helps also.

Can also reduce heat with a fuel controller that adjusts pump speed based on demand (rather than the pump running at 100% regardless of fuel demand).

[jhein]

Made some good progress today. I got the tank straps bent/shaped about as good as I think I can, so that's done. I got the hole cut for the access door. Mounted the relay and circuit breaker. I'm gonna pause here because my suspension parts are on the way from PTFB and I want to do the rear before I "permanently" mount the tank. But really, everything is pretty much done except for the fuel lines. I still need to do some proper cable management, but I'll get that all tidied up.

[jhein]

I've made the decision to ditch the transverse muffler setup. It will just make things much easier. Plus, I got the Pypes SGF41V, dual violator muffler setup so that will mean a little better flow and a much more aggressive sound. I ordered the kit from Summit. It was $14 less and had free shipping. It's shipping directly from Pypes who were going to charge me like $180 for shipping. So not a bad deal going through Summit.