The Merkur Club of America Forums

I need to send some Saab parts out for ceramic coating, and since the XR just passed smog I'm going to do what I always said I was gonna and see about getting a 3" downpipe. I was originally thinking about rolling my own, but I've got no chance of getting anything fancy through smog, so I'm looking at Stinger's solution built on the stock 5-bolt swing valve housing. My plan is that, their 3" alumized downpipe, and a flex section before the cat (to cut NVH a bit), with the hard parts ceramic coated for maximum disguise. Heh. I feel lame.

Anywho, I'm curious about two things:

1) Stinger lists both an aluminized steel and a stainless steel elbow. I don't care about rust, and everything is gonna be ceramic coated anyway. I'm curious if anyone has any opinions on the quality or appearance of one part versus the other.

2) Their 3" downpipe is now called "downpipe II" and the description says "bolt in for SVO and TC, also fits Merkurs. Does this "also fits" means "fits with adjustments" or "is also bolt-in, but we didn't want to put two ands in a sentence?"

Any comments?

FWIW, I'm aware that MD sells this stuff, but those parts are WAY more than $200, and rightfully so being stainless. I just don't need (and don't want) stainless, so I can't really justify the price premium.

AFAIK, with some experience with a downpipe from Sacramento Mustang, it'll need to be shortened somewhat for a perfect fit in a Merkur, which is just a little shorter on the down section than a Mustang. I would ask them, however.

I like the flex sections they sell on silicone intakes dot com. If you look at the inside it is smooth just like the outside, with the spring part in the middle and not visible. Some other brands have the spring in there messing up the exhaust flow. I see broken rusted flex sections at junkyards all the time. So I think a nice SS one is worth it.

Thanks guys. Shortening is not a problem so long as the bends are generally in the right place. And by "not a problem" I mean "not a problem for whoever I get to weld this up and install it." I've been sitting on a welder for a year and still haven't fired it up once to use it - that has to be a priority this year.

Good tip on the siliconeintake flex section - a lot of the IC system on this car is made up of their parts and I used their "intake pressure tester tool" just last month... I've had that thing for YEARS - it's proven a fantastic investment. I need to crawl under the car and see how the cat is installed so I know what my options are for installing the flex.

Another thing I want to think about is some sort of flange somewhere. I think I'm okay with the elbow and DP being one piece, but I definitely want a flange at some point before the cat in case things need to come apart, or I need clearance for work.

I wonder if there is room to do the flex section immediately after the elbow, and put a coupler of some type (v band maybe?) after that. That would make for a very convenient assembly.

thesameguy wrote: ↑Thu Feb 21, 2019 11:47 am Another thing I want to think about is some sort of flange somewhere. I think I'm okay with the elbow and DP being one piece, but I definitely want a flange at some point before the cat in case things need to come apart, or I need clearance for work.

I wonder if there is room to do the flex section immediately after the elbow, and put a coupler of some type (v band maybe?) after that. That would make for a very convenient assembly.

Good idea on the flange(s), as besides facilitating maintenance in general, you can disconnect your cat at some point to see if it has become clogged (performance dramatically improves when disconnected). Mine's all welded up (PO), and I really don't like that.

I think there's enough room for a flex section where you say (or maybe incorporate it into the removed section), but I would check for Smog legality on that, too.

The Sacramento Mustang downpipe was installed on my nephew's car. The shop installed it as-is (was?) which required a bend back up to the cat level. There was a section of the downpipe which hung below the rest of the system. That would be unacceptable, to me... I would have had them redo that!

The exhaust is mostly a Stinger 3" system from ~12 years ago. I stuck a Magnaflow 3" muffler in there somewhere as well as a 3" cat parallel to the exhaust. I *think* when I had the shop do that work I installed some sort of coupler before the cat as I *hate* one-piece monolithic exhaust monstrosities most custom shops build. But, it's been ten years since I've looked at it.

If it wasn't for the (effective) 90 degree bend needed between the downpipe and cat I would probably do the downpipe custom, but since there are at least a couple specific dimensions I really prefer prefab parts from someone who has measured.

I am 100% sure a flex section is a technical illegality, but the whole downpipe is a technical illegality anyway. My experience is that most shops won't hassle you if it looks like good work and maintains placement & function of the important parts (O2 sensor & cat, namely). I'm *hoping* that plays out here, too. But, if not I guess I will be that guy swapping on factory parts every other year or whatever. Hey, maybe by the next time I have to do that they'll get SB1274 (I think that's the designation) through and I won't have to pass a visual, just functional & emissions. That'd be dope.

thesameguy wrote: ↑Thu Feb 21, 2019 1:39 pm I am 100% sure a flex section is a technical illegality, but the whole downpipe is a technical illegality anyway. My experience is that most shops won't hassle you if it looks like good work and maintains placement & function of the important parts (O2 sensor & cat, namely). I'm *hoping* that plays out here, too. But, if not I guess I will be that guy swapping on factory parts every other year or whatever. Hey, maybe by the next time I have to do that they'll get SB1274 (I think that's the designation) through and I won't have to pass a visual, just functional & emissions. That'd be dope.

FWIW, I signed the petition... there's hope for California yet.

Viva La Revolucion!

I *guarantee* that's coming. The guy I bought the XR from actually works for CARB and he and I stay in touch.

With Y2K+ cars only subject to e-testing, there is clearly going to be a point in time where shops are going to stop investing in the tools (including the dyno!) needed to perform tests on older cars. The last car subject to dyno testing is now 20 years old - nearly double the average age of cars (11.3 years). In two years, there statistically won't be a meaningful number of cars needing that test, and shops are gonna be really recalcitrant to buy $10,000 dynos to test a car a day.

My "contact" thought that exemption was going to happen last year, so it's definitely on the table. Right now, it's just a waiting game, and I got time.

You should get your E6 ported as well. Huge torque gains and quicker spooling to along with your downpipe. And it can't be detected by the tech. I also thought there was a 3" bolt-on downpipe. Was it Rapido? Or was his like 2.5" and even that's an upgrade over stock.

Esteban wrote: ↑Fri Feb 22, 2019 6:16 am You should get your E6 ported as well. Huge torque gains and quicker spooling to along with your downpipe. And it can't be detected by the tech. I also thought there was a 3" bolt-on downpipe. Was it Rapido? Or was his like 2.5" and even that's an upgrade over stock.

Mike at Merkur Depot shows some downpipes on his page:

http://www.merkur.50megs.com/catalog_3.html

Glad you posted that link - I did not know MD made aluminized versions now, which is cool.

The decision point comes in that Stinger's two-piece option (elbow + DP) is quite a bit less than MD's 1-piece. For me, I *want* them in two pieces so I can add a flex section... paying the premium to save fitting them together isn't worthwhile to me. I will say that it look like Mike also addresses the swingvalve portion of the flange, which Stinger does not. Mixed bag, as that additional welding does draw attention I don't want, but I'm sure it's a performance improvement.

FWIW, I talked to Stinger and the "also fits Merkurs" refers to the fact that the generic fox body bends result in tight clearance on the XR's chassis brace. They indicated that if used in combo with the 3" downpipe (where welding is required) there is no issue with fitment.

I crawled under the car yesterday and remembered what I had the shop do way back when:



I had them add a 3" section before the cat so I would have room to add a flange in the future. Close enough!

If I build my downpipe with a flex section I will need to also build a bracket to support the cat. Right now it's basically hanging from the turbo, which isn't ideal but it's been like that for 12 years. If that rigid connection is gone the rest of the exhaust will just flop around, so I need to device something there, probably off the trans bracket. NBD.

Edit: The E6 is already massively ported and ceramic coated in & out. TBH, the current config works very well as a road car, even with only 12psi. The turbo spools very fast, lag is minimal, and it's rare I find something I can't overtake. No, it's not gonna pull a Z06 on the highway, but I really don't need more incentive for racing on the street. My 0-80 capabilities are excellent... I'm not sure what I hope to win with the downpipe other than satisfy decade-old curiosity.

That doesn't look too bad. I've seen a few 3 inch setups that hang down and look bad when you look at the car from the side. Maybe that's all the "also fits xr4ti" downpipes out there. I've been told the Rapido downpipe was 2.5 inch. The borla cat backs were 2.5 inch in with dual outs.

Anybody try one of these?

https://www.ebay.com/itm/T3-T3-T4-5-Bol ... k:183:pf:0

I literally just got this:



But I think the issue is that the extra inch that part takes sucks up valuable space you need for a smooth bend. For big pipe and a smooth bend, you need the flange to take up very little space, so the adapter+elbow solution is probably the best bet.

I got that for my Saab but would order another for the XR if I was pretty sure it would work. I am pretty sure it would not.

Is that pic of a 3" v-band with a 5 bolt flange and a swing valve? The ATP piece? Those are really nice pieces if so. And you're right about the fact of not enough room in an XR to weld a flange on a 3" 90° pipe at attach it to the v band on that.

Here's ours:

Stainless ...


Aluminized...


4.25" opening at the flange, tapers down to 3". The most free flowing, restriction free downpipe for the stock XR4Ti turbo.

The biggest drawback to the other elbow you are asking about is the fact there is still a 2.25" bottleneck before the 3" piece is attached. Its an important place where the exhaust gasses need to expand, as well as expel as quickly as possible.
(One of the many reasons the Cosworth turbine housings are so sought after. A 3" downpipe bolts directly to it AND the exhaust wheel and wastegate flap open up in a 3" diameter environment. )

That being said, you will get to the 3" section a lot sooner using the elbow in question.

Fitment of downpipes...Mustang fitment vs XR fitment. It seems (all of) ours have one extra bend in them that is not present in anyone else's that I have seen: