the flyin' scotsman

From the '88 Technik Service Information:

Namvet

I did a single pipe and Rear muffler. Kinda loud , but not too much. Sure picked the engine up. Noticeable difference in accel and response on throttle. (Oval 3.5 Inch ..gentle bend and careful fit)

worf928

Hmmm.... another reason for me not to 'upgrade' to PET 6 perhaps. IIRC you and I have seen this before - where PET 6 'disappears' some part numbers. Does PET 6 show a number for the M637 option?

SMTCapeCod

There's a similar muffler in lieu of cats for OB cars shown in my shop manuals, I tried to get a used one for my Euro, including corresponding with 'breakers' in Europe. Consensus was that they are heavy and may not provide much better flow than the GT cats I have on there now. As I said, thats for the OB units. I did see one on Ebay once but the seller was asking big bucks.

I had my OB with Ott X and Spintech and it was insane-loud (3.5" pipe). Added a triple core straight-through final resonator..not much change. Back to GT cats, still loud but OK.

I might be interested in those East Coast center mufflers, if you're feeling generous and want to PM me the info?

Bill Ball

Hey, Rich:

You have a muffler. That makes a whole lot of difference. There is no misconception - if you remove the stock or aftermarlet muffler and run an RMB, it's loud with an X-pipe, but this also depends on MY, as the resonators vary, as mentioned in my quote of Louie's comments.

the flyin' scotsman

I did recall having a PET difference discussion previously but didn't remember it was you Dave; no offence.

PET 6 lists 3 part numbers for each intermediate resonator the third number being a duplicate of the second and has the M637 option number after it.

The second and third part numbers are the 928 111 094 04 & 093 04 smaller resonators so perhaps the M637 option is for the lighter CS exhaust system?

the flyin' scotsman

You have a PM.

SMTCapeCod

Oval-- that's great! Contemplated that for a bit, no talent in the area up to the task and hefty price tag. Would love to see some pictures of it, if you're able.

worf928

None taken

Does anyone know if PET 6 can coexist with 5? I'd like to be able to see the recent supersessions but don't want to lose the historical info in 5.

I dunno. The mid-numbers I quoted (the ones missing from PET 6) are the smaller resonators. Wasn't there some discussion way back about the larger resonators being used for low-noise counties like Switzerland? Else if there IS actually a difference between M637 small resonators and 'normal' small resonators how would we tell apart from the numbers?

SeanR

Running the smaller resonators here, stock cats, RMB and I think it sounds perfect. Adding the X-pipe with cats will be next but I am a bit worried about the change in sound.

In the DFW 928 group we have all the different set ups and to be honest, I don't notice much of a difference in sound between the X-pipe with cats and the stock cats. I'm hoping that will be the same in my case.

Panzer9

What is the cost/ performance relationship of the H- pipe vs the X pipe?Is the H even a viable option to increase power. I'm asking, cause a friend has a new one in his garage he purchased for a now entinct shark -- Thanks!

the flyin' scotsman

M637 Special Version "Club Sport" 88 ..............the option code for the lighter exhaust system.

SMTCapeCod

Just my untested bench opinion here...but the only H that I know of is the Bursch setup. I had one in front of my 928SP/Mufflex 3.5" system for a while. It corroded quickly! The pipe diameter is not ideal, nor is the H configuration. However, if you are putting it in place of stock cats, my guesstimate is that it would improve output, at least at the top end, by offering less restriction than the stock cats.

blau928

Bill,

I only have the mufflers in place of the resonators.... It is very similar to having resonators an an RMB.. From the mufflers (where the resonators used to be) back to the tailpipe ends, there is zippo, nada, just open tubes......!

EspritS4s

Anyone have a rear muffler for sale cheap? My car came with a makeshift RMB, but I'm considering the additon of an x-pipe followed by high flo cats.

-Gary