This is the header in question:
Benson Tuning 4-1 Stainless Header
It's available through their website or on eBay. Same price. I ordered through eBay just because it was easier, free shipping. Purchase was painless, and the item arrived in a reasonable time and packaged well enough.
It's two pieces. The down pipe is a slip-on. I had to research this. I really felt like it should have a clamp or something, but no. "Old hotrodder trick", I guess. Once the engine starts heating up the collector pipe, it expands against the outer down pipe part which is slightly cooler because it's exposed to ambient air. It should stay tight and not leak. Physics! Seems feasible. It is a nice tight fit. I also read that you could smear some exhaust sealant goop in there if you wanted to, but it makes it a lot harder to take apart.
Came with a gasket, but it's JUST the header gasket, not the usual combined one-piece header and intake gasket? Who uses that? Not me. I just left the old gasket in place and used it. Also came with a clamp, I assume it's to clamp the header pipe to the tail pipe? I didn't use it.
The good news:
It's pretty. Nice welds, nicely polished. Looks well-made. The flange is the perfect thickness, and mounted with ease. It's got a bracket on the collector pipe that's supposed to bolt to the transmission.
Top View:
Bottom View:
The bad news:
Something is amiss with their jig. Either the angle of the pipes coming off of the head flange is off, or those pipes coming off of the head flange are a touch too long, or the angle of all 4 pipes is a little off. Maybe all of the above? For as pretty as it is... it just doesn't quite fit right. The collector pipe just barely makes contact with the lip of the frame rail.
There's a 4" gap between the engine block and the frame rail, and they couldn't make a 2" pipe fit in that gap. Kind of annoying.
Now, I don't have or want a "perfect" Midget, I'm not afraid to "make it fit". I didn't WANT to adjust the car to make it fit, but it seemed a lot easier to do it that way than to try to manipulate the header itself. Yes, I could have consulted the seller/maker. I just didn't feel like doing it. When you buy a $150 header on eBay, you adjust your expectations accordingly. I'd have been THRILLED if it fit perfectly, but I'm not surprised or overly sad that it didn't. If I wanted a perfect fit, I'd pay $500 for a header.
So, getting the header firmly fixed to the head and looking things over... I thought I could maybe just bend the whole mess over by hand. But, nah. It's pretty stout. And if I applied leverage, I'd either kink pipes, or damage the collector joint. Not wanting to cause more headaches, I gave it some more thought.
I did consider that it's possible that my engine is not properly centered. Always a possibility. But, I recently replaced the engine mounts. And while the trans mounts are sagged, the engine mounts are right where they should be and the engine is not canted in either direction. Could be slightly tilted rearward, but that wouldn't be a problem.
So, after taking a deep breath, I took the easy way out. I broke out the sawzall and the cutting wheel, and trimmed the lip off of the inner edge of the frame rail. It's not a "full notch", I just cut notches in the lip and bent it up even with the edge of the frame rail. I threw some paint on it, and will clean it up and improve it later.
Here's the clearance after modification:
I also had to clearance the triangulating bracket off of the lower control arm mounting point. I opted to just cut it off. A project for future me will be to create a beefy custom bracket to go there and properly clear the header.
View from the wheel well:
Because the collector flange is positioned about an inch outboard, the bracket on the downpipe also doesn't line up with the bolt hole on the transmission. I'll have to create some kind of bracket extension to attach that. (and that attachment also keeps the slip fitting in place) If the header itself were made properly, there's no way that THIS wouldn't perfectly line up with the bolt hole on the bell housing. That pretty much negates the possibility of the engine being out-of-place in the car. They just built the header wrong.
Header Flange Bracket:
That pretty much covers the header itself and mods I had to do to fit it.
Hooking it up to the rest of the exhaust:
I wanted to make this easy to work with in the future, and I was able to find a pretty cheap stainless steel band clamp kit on Amazon. It was actually cheaper than standard flanges and a flange gasket, or maybe $5 more. Excellent quality piece. So, I went with that.
When the WHOLE EXHAUST is done, I want it to be "nice" or "nice enough". So, the permanent parts, I'm trying to do right. The down pipe is 2"! Freakin' huge! I'm of the opinion that somewhere between 1.625 and 1.75" would be plenty big enough for my purposes. 1.75" is pretty standard and cheap, so I'm going with that.
I got a stainless 2" to 1.5" cone reducer and welded that between the down pipe and one of the band clamp flanges. Tidy! I cut about a half-inch off of the end of the reducer to get it to the 1.75" of the band clamp.
I also added a bung for an O2 sensor. (adding an AFR gauge was the rationalization for this whole project to start with!) After all of that was welded, I pressure tested it. How, you ask? Put a hand over the end, thumb in the O2 bung hole, and blew in it! Tight!
For the back half, I'm planning to replace that all later, so I just need to hack something together to fit the existing tail pipe temporarily. I got a 1.75" flex pipe. Quickly learned that stuff is a pain in the ass to weld! You've got to turn the heat WAY down, and it's still way too easy to melt through it. But, I got it done. Flex pipe to the other half of the band clamp done!
Now, I need to weld the flex pipe to the stock exhaust pipe. BIG gap between 1.5" pipe and 1.75" flex pipe. But, I found that cut off piece of the cone reducer. It was a nearly perfect fit inside the flex pipe, and an exact fit to the stock 1.5" pipe. That all welded together nicely. Not pretty, mind you. Just nicely. It's got some pin holes in it, but I don't care. It's temporary.
Here's what that all looks like:
When I rework the back half of the exhaust, it will be all 1.75" with proper mandrel bends and a properly sized (but quiet) muffler. For now, this will get me back on the road. (if the damned car would start, but that's another story)
