911Dave

Assuming I start out with a properly tuned car, if I then swap the stock muffler for an RMB and swap the chips for Autothority ones, will any re-tuning be necessary?

911Dave

bumpity bump

Vlocity

Nope.

You could probably add a rising rate fuel pressure regulator at some point for a few more ponies.
The autothority chips will make a noticeable improvement in driveability. At least they did on my 85.

Ken

RDS928S

Dave,

why don't you install the 928 Specialist modular x pipe with or without cats in combo with the Autothority chips. That set up will give aprox. 50 bhp and the car will be civilized in the sound department since you keep the stock exhaust.

I have already installed the Autothority chips and am waiting for the x-pipe delivery. Dave @ 928 Specialist says the sound will be awesome with that set up and not PO the neighbors.

Good Luck

dr bob

You'll definitely want to add the adjustable rising rate fuel pressure regulator to this setup to get all those ponies out. The Autothority chipset responds well to as additional 2-4PSI on its own. The extra breathing with the X-pipe will take full advantage of that too.

Anybody running the DR X pipe yet? Inquiring minds and all that.

RDS928S

Bob,
what is the process in installing the rising rate fuel pressure regulator system?
Who sells them?.

Thanks Rich

911Dave

That would be my question too. Thanks for the advice Rich. I think I'll go the X-pipe route and hear how it sounds before buying a RMB.

James-man

Our site sponsor, 928 Specialists sells a rising rate fuel pressure regulator. I think it is in the performance mods section. I think that they run well under 200 bucks.

I have had a RMB and autothority for around 8 years and am just now getting around to doing more with the exhaust a la X-pipe. I think that the best bang for the buck for you is an X pipe at this point. If you can stand more sound after that, then go ahead and try an RMB.

Since Motorsport has done multiple iterations of dyno tuning, specifically on an 86.5, I believe that it is probably the most optimised of the X-offerings for the 928 community. Being able to use the Ott X as a baseline dyno says quite a bit. Dave Lomas is just starting to ship them, so unlike header purchases, etc, this is like buying right off the shelf.

I dynoed last spring in the low 270's. I am interested in getting RRFPR and would hope to do some tuning before installing the X so that I can get a "Best" set of numbers for my RMB + Authothority, a Baseline X, and then a tuned X.