Crumpler

I had mentioned this in another thread, but I'm looking at various options for the 86.5:

Current setup: stock S3 manifolds, Xpipe, no cats, stock intermediates, and RMB.

Assessment: Barks and snorts, good power. No complaints from the neighbors yet..., but the highway drone is getting to me.

Goal: always interested in making her be all that she can be. She's essentially a street driver, but if there's another bolt on HP upgrade I want it...

I'm also looking for a Borla type tone, maybe a little more sophisticated then whats coming out of her right now.

So what do you gentlemen suggest?

In terms of headers, MSDS seems to be the only game in town for the 86, but I'm not thinking there would be a big difference between those and the S3 manifolds?

I've seen the performance headers by Greg and Carl -- they both look great, just a little out of budget.


I was looking at some of the systems today, what would be the effect of ditching the stock intermediates and replace them with a Borla Pro on each side?
The xpipe is 2.5 inch already. I could convert the rest from the stock pipe to a 2.5 inch at the same time. If I did it that way I could keep the RMB in place, eliminating some of the hassle with the S3 battery box and the dual set up.

Thoughts?

The Forgotten On

One thing others have done is gotten rid of the mids and straight piped it, then put back on the stock pumpkin. It's worked to get rid of drone for a few S4 owners.

Crumpler

Thanks Blake, I had not thought of that. Wasn't there somebody that did a mod to open the his S4 punkin up on the top, or did I make that up?

The S3 iron pumpkin is sooooo damn heavy! I saved it of course, if I ever needed to go back to stock -- so I could do it.

How much do the stock intermediates do anyway?
They are also big and heavy, that is a given, but I'm guessing not real efficient. Especially when we look at what's available now.

I could also look at high flow cats I guess, anything that restricts flow in the system would change the tone to some degree right?

Kevin in Atlanta

I have 928 Motorsports X pipe, Cat, GT resonators and GT rear muffler. Had to ditch the RMB - too loud. Love the results in-town and at speed on the highway.

jcorenman

That's funny, I thought your thread title said "Ultimate".

The mid-resonators are empty cans with a perforated pipe running through. If you go with headers then I think you want larger pipe all the way back, e.g. the dual 2.5" mentioned above.

Our GT sounds pretty good, and is Devek L2 headers with a 2.5" x-pipe and dual 2.5" back to mufflers in the mid-resonator position and then straight out the back. Louie Ott that together for the PO, to me it is about right-- authoritative without being particularly loud around town, with a nice (and relatively loud) howl as you wind it out. The mufflers are key, ours are Bullet brand which Louie found, since purchased by Magnaflow and NLA.

Cheers, Jim

Crumpler

Kevin, that sounds pretty cool. I will look at that. I haven't really looked at 87 or later mufflers mostly because the placement of the 86.5 is so jacked up in comparison... but if I'm going custom, I'm sure it could be done.

Jim, that's ironic, the car on Ott's webpage was my inspiration! Is that yours?

Man, I would love to find a set of Devek headers, so this is a standing WTB for anybody reading, lol.

In fact, I'd like to hear more about Devek. As one of the newer guys, we hear about this mystical group that was a high point in 928 lore... then it was gone.
Always been curious...

bureau13

My S3 has MSDS headers, cats and a Borla. It's separate all the way back right now...it sounds great without being particularly loud under easy driving, but there is some highway drone. I have an X-pipe that I want to replace the cats with, no idea how loud that will make it...but the damned cats are welded to the rest of the exhaust, and I haven't figured out the best way to proceed yet.

It does sound really good though. I'm not sure what the contribution to either sound or performance is in terms of the headers though...

jcorenman

Louie had an exhaust pic that was ours or very close, years back but I am not finding it on his website. The pic on his site of a complete exhaust (link) is for stock manifolds, but the back ends are the same.

Here's some pics from the PO for our system in original form, we've since added hi-flow cats and cleaned things up a bit. It's all stock 2.5" stainless mandrel bends, simple to do with time, patience and some fabrication/welding skills.

Crumpler

I've got two Borlas on order, I'm going to try to imitate Jim's system.

To maintain the 2.5 pipe, I will have to ditch my current RMB, which is 2 inch.

Maybe I will splurge and do some Borla tips as well.
I'm assuming the intercooled tips are 100% marketing right? I'm hard pressed to buy in to any advantage other then cosmetic?

jwyatt8171

Jim, How much skill involved when buying mandrel bent stainless? Im considering doing this myself. I may mock it up, tack weld, test fit, then take to a welder for final welding?

I will be doing this when $$$ loosens up some. Daughters wedding is only 3 weeks away.

Maybe I can get a project or two done this year. Maybe.

Darien

When I was searching for the best exhaust set-up I contacted the wizard himself (Louie) who made dyno runs with several different configurations.

As I already had his 2.5" X-pipe with 2.25" stock pipes, Louie recommended 2.5" exhaust all the way back versus the 2.25" stock pipes. He offered a few options for mufflers to fit in the resonator locations and I chose Dynomax 17232 Mufflers.

My results were awesome sound (click link in my sig) and gained in hp/tq with a no restriction flow

The pics show how the Dynomax mufflers fit. They have the correct offset for AT's and would allow plenty of room for 5 spds.

jcorenman

Almost none, to buy mandrel bends.
The tricky bit comes later, but your approach is the right one: Cut the pieces, tack them in place and then get someone to weld them properly (or learn to do that yourself). I'm a lousy welder but managed to do some simple mods. My one mistake was not leaving enough clearance between mufflers and the rear crossmember-- exhaust pipes get hot and grow in length, and my 1/4" clearance went to nothing when things got hot.

dpower$

Do you have to have CATS where you are? My early 86 has MSDS headers into a magnaflow 2 in one out muffler where the cats were originally with 3 " pipe out of the muffler to the rear. I absolutely love it. I get many compliments from "car guys" but it would be too much for many others. Under load at high revs, the exhaust plus the supercharger whine combine for a shriek much like a F1 car

skpyle

Darien Nunn: That is badass! I will keep your setup in mind when it comes time for exhaust on the Red Witch.

Thanks!

Seth K. Pyle

Crumpler

Still in the planning stages.
Ok, so exhaust is off the car and some parts have arrived -- mufflers and tips.
I'm going to R/R the heat shields as well.
I have not ordered pipe yet, the welds can be done but I'm not convinced I can pull off the bends myself....
I've seen the pro bending machines go north of 50 grand, and my impression so far is that the entry level benders (200-400$) are not able to bend 2.5 pipe, at least not well? That's my first question right now.

I could buy pre-bent angled pipe sections, but that sounds pretty sketchy if I need a custom fit.
I talked to a local custom exhaust guy yesterday as a back up, he was pretty jazzed to hear it was a 928 BTW, if I need to I can get a quote and punt to him. But what do you guys think? I'd like to DIY and learn it myself, but by the time I buy the mandrels and bender....