84_Carrera

... anyone got any useful insights before I crawl under? TIA.

scottb

Start soaking all of the exhaust nuts and bolts in PB Blaster now. Let them soak for as long as possible before you try to loosen them up. The longer you give PB Blaster, the more chance you have of getting things apart without too much difficulty. If, after soaking everything in PB Blaster, you still can't get it apart, you may need to heat the nuts with a MAPP gas torch until they're cherry red, and then break them loose. If all else fails, youll have to start cutting with your Dremel tool. Also, if the Fabspeed doesn't have replacement nuts, bolts and washers, you should get some and not re-use the old ones.

Good luck!

BER

Scottb gives some very good advice. The only item I would add is you should replace the gaskets at each end of the pre-muffler.

There have been some recent threads on various Porsche bulletin boards about fitment issues with the Fabspeed pre-muffler. You might want to do a "Search" here on the Rennlist and on the Pelican BBS for more insight. Hopefully, you will get one of the properly aligned pre-mufflers and have no issues other than getting the old nuts and bolts off. Like scottb said...HEAT is very effective.

Bruce
'84 Carrera
'77 911 (RoW spec)

84_Carrera

Yup, I'm a believer with PB Blaster, living here in the northeast.

Bought the matching copper gasket set as well, didn't know if the kit came with new fasteners front & rear though. Talked to Joe about the recent fitment questions & pointed him here in case there was a new issue he wasn't aware of vs. the old one.

What size (assuming hex) is the O2 sensor?

It appears to be a really straightforward & simple replacement, which is usually when I get burned on something stupid.

Thanks guys.

ron mcatee

O2 sensor is 22mm and can be fairly hard to break loose. You can also use a Crescent wrench (adjustable metric). Do it prior to removing the Cat. It gives you a hard mount to put torque on the sensor. Suggest you remove the left rear wheel for additional space while doing the removal and installation (R&R).

fixnprsh

soak them with a penetrating oil overnight, tighten the bolts (just a hair) before losening them, dont know why It works, but I have never broken an exhaust stud or bolt yet.

scottb

For the O-2 sensor, I bought a cheap deep socket at AutoZone, and then cut a slot in the side for the cable with my Dremel tool. Worked like a champ!

84_Carrera

I have a couple of different 22mm O2 sockets, wrench, etc; just didn't know if it was the same size as what I was used to working with.

84_Carrera

Pre-Muffler came in today. Wow is that a sharp looking piece, nice welds & everything. Will probably give it a go one night this week, depending on the snow.

scottb

Start soaking in PB Blaster now! Give them additional sprays every day until you're ready to do the work. Good luck.

84_Carrera

...and the Pre-Muffler's in.

Absolutely no fitment / aligning issues with it. The upstream triangular copper gasket (round exhaust port) had mis-placed mounting holes (opened them up just a bit and had no further issues).

I didn't notice any real difference in the exhaust note, however I did notice the exhaust was more visible on startup (vapor, not oil).

I do wish they included new bolts with the unit. Other than that, my second 911 project is now just a chalkmark on the board. FYI, I left the splash shield and brackets off for now. I figured it was to prohibit radical temp changes from cold water hitting the hot cat & fracturing the catalyst (thoughts? potential problems?)

Off to the dyno as soon as I can, then the next step - replace the Weltmeister chip with Steve Wong's.

One last question... how often should those exhaust couplers be changed (the silicone ones that look like turbo diesel hose)?

82Targa

84_Carrera, can you post once you get to take the car our for a drive? I am curious to see if you notice any improvement from just the pre-muffler.

BER

Sounds nice...I think you will be pleased with the results after your test drive.

You should have no problems leaving the cat shield and brackets off the car. As a matter of fact, I don't recall seeing a 3.2 Carrera recently with the shield still in place. You can buy the shields at swap meets pretty cheap which should tell you something.

Enjoy your freer-flowing engine!

Bruce
'84 Carrera
'77 911 (RoW spec)

84_Carrera

I hesitate to comment on results using the Butt Dyno, as I'm a firm believer in actual documentable results, but it does feel a little better in the 3500-5000 range.

ron mcatee

84 Carrera, you have any mounting points on the Fabspeed pre-muffler for attaching the heat shield to it. The reason for the heat shield was to protect the bottom of the engine and seals from all the Cat heat. With the pre-muffler, the heat dissipates fairly fast. If you do want to install the heat shield, you'd have to weld mounting flanges to the pre-muffler to secure it.

My Fabspeed pre-muffler was misaligned during production (I got one of the bad batch) and wouldn't fit when I tried to install it, but Joe Fabrini said return it and he would fix it. I returned it and after 2 months of bugging Joe, they finally sent it back. It was still not correct, but I didn't want to go another 2 months or more waiting for another fix since I had nothing to put on the car. As a last resort, I had a friend realign it by heating it and working it into position.

It has a nice sound and eliminated the resonance that I was experiencing at 55-75 mph. I just wish Joe at Fabspeed had sent me a new one immediately instead of spending so much time reworking it and still not getting it right.

Glad your experience was much better than mine. I've driven Porsches for almost 40 years and this was the first time I had a bad experience on any parts. I guess I was lucky over the years. Based on my experience, I wouldn't buy another part from Joe nor refer anyone to him. The only satisfaction for me would be for Joe to step up and send me a correct one and heal my wound.