Cfiles0920

so i have a supertrapp exhaust that i dont really know anything about. it is supposedly tunable?? no clue. but anyway it has rattled itself to pieces. and it is quite embarrassing to ride around sounding like i have a can of coins on the back of my car. dont really have the coin at the moment to drop on a new exhaust. is it possible to remove the baffle entirely and run an open -ended pipe without damaging the 'ole 3 liter? if not where can i get a new baffle/plates/hardware?? i went to the "supertrapp"
website and no results. seems like they make more atv stuff than anything. thanks for any help.

part two is a bit more frustrating.....my ac/alternator belt WILL NOT STAY TIGHT. therefore causing a horrific squeaking. i had this problem before and it was my compressor shifting because of sheared bolts. problem corrected. so now i dont know why the damn thing wont stay
tight. it stays tight enough to work, but its not comfortable driving around with a fear of losing alt. power. any suggestions? not really wanting to delete the a/c, not planning on making a track car. thanks for all help....

V2Rocket

dunno about the exhaust but accessory belt tension is dealt with using the little rod that goes between your engineblock and your alternator..they fail alot, maybe that needs to be replaced

Cfiles0920

it seems like its working fine. what do you mean by fail?? there is no visible damage.

PSUice944

Check your ac pivot bolts that sheared... if they sheared again, you have a larger problem that I have dealt with before!

If those bolts are still intact, you need to get that "turnbuckle" adjustor working for you on the tension, it could be worn out.

If those bolts are gone, I tried to replace those about 5 times before I gave up and had to replace the damaged bracket, which concequently is part of the motor! I used this opportunity to drop my non-working ac and move my alternator down there with the ac delete bracket. In the short term, you can use some belt grip and extend the tensioner about a far as it will go and it will let you "hobble around" for a while until you fix it right. Oh, and avoid the rain in this situation!

Spidey944

Beware extending the aduster too far, this makes them weaker. Get a shorter belt and adjust the adjuster back.

Cfiles0920

well its not adjusted very far, i put a new belt on it about 2 weeks ago, and i only got about 3 whole turns before the belt was tight. now its kinda loose, i can adjust it tight no problem and not worry about the turnbuckle being too spread out, but whats to say 3 weeks from now it wont be loose again. it seems like the belt is stretching but i dunno. i am ordering a new compressor so when i get that ill pull the old one off and see what the deal is.

anyone have any ideas about the supertrapp????

PSUice944

Supertrapp? I remember summit racing selling that with parts, could try there?

white924s

Supertrapp mufflers are tunable, usually by adjusting the number of plates on the back. They do have a few automotive mufflers listed on their site (they're universal mufflers, and they are definitely somewhat buried under the motorcycle and atv stuff). Or you might want to try getting the dimensions on your current muffler and giving supertrapp a call to see what they can do.

Unfortunately, I'm not sure how much cheaper you can get the core vs. the whole muffler, but I don't know....

JonH

I ran a Supertrapp on my Scirocco, you tune them by playing with the number of end plates. You can also repack them, but I would just go buy a std. performance muffler, there are better exhausts IMHO for the 944's. To get the most power I put all the plates in the end (most open) and it was really loud and tinny. A 3.0 is a huge 4 cyl. and I would probably use two Supertrapp's to get more flow. There is probably a reason you see more of these on ATV's and motorcycles. It's just like a glass pack with the end cap off so you won't hurt your engine if it's open, just your neighbor's car alarms.

Oh, and yes Summit sells the repack and disc kits. Just saw them there yesterday. Go buy a decent Dynomax or something for half the price!

Cfiles0920

yeah, decided today after hearing the piercing sound of the end cap removed, time to go pay for a decent performance muffler....thanks guys...
PSUice how did you fix the motor bracket for the a/c???????

eniac

I used Supertrapps on a V8 Monza hotrod I had until I twisted the car in half from too much power. Sad day but it was a blast! It did sound great at 9k rpm with 15 disks in each side but way too loud. The problem is to get these quiet enough for the street, you have to have so few disks that the backpressure would be way too high. For old reed valve 2-strokes, these are perfect. For a large 4 stroke 4 cyl that needs to breathe, this is bad. I would say the only way to run these effectively is one for each cylinder. lol.

You can buy new disks and also the repacking material depending on what style you have. Check thier site for a "Where to buy", or a supplier list and one of those companies should be able to get whatever you need.

As for the alr belt, what brand belt are you using? I have the same problem since switching my alternator to the Nissan one, I just ran to a local parts store buying whatever belts they sold to get the proper size when doing the conversion. The belts were VERY inexpensive and now I know why. Mine keep stretching and slowly loosens then I have to tighten it again every couple months. I recently took it off and measured to be sure it was indeed stretching, it is.

If nothing is broken or worn to cause this then I would suggest getting a better quality belt such as an OEM Porsche or Conitech.

Lemming

I run a supertrapp on my 924s3 trackcar. Currently running without discs and it is loud but I don't get black flagged for noise. I would not want to run that setup on the street.

I had good luck with a dynomax turbo shorty muffler prior to the supertrapp.

PSUice944

Well admittedly, I wasn't the one who did the work as my wrench was tackling something bigger for me at the time and I had him do this as well. As I recall, the base bracket takes some "digging" to get it off the motor for replacement.

A popular thing amongst us old 944 guys is to ditch the old busted AC entirely and relocate the rather heavy alternator down to that lower location. This takes a different bracket (a potential solution for you) and matching shorter belt. This used to be a factory option from what I recall, and I know there are kits out there to get you started if you want to go this route.

I know this can be done with factory parts, new or used, or some aftermarket solutions that may be better.

In short, I would search "AC delete" and start to look for more details... Good luck!

Lemming

AC delete is not really a good option in South Alabama

I kept breaking turnbuckles on my 3.0L so I eventually just replaced it with a steel bar. I determined proper belt adjustment, drilled the bar and installed using a pry to tighten the belt.

With the 3.0L it is important to make sure that you balance shafts are aligned properly. If not you get excess vibration and that causes things to break (hence your sheared bolts). In addition, the 968 went away from running a harmonic damper on the pulley and instead used a dual-mass flywheel. Your car is running a single-mass flywheel and hence you might consider going with an S2 harmonic damper. I did this on my track car and it cut the vibration quite a bit. Of course, I run solid motor mounts that don't help the situation

Jfrahm

The turnbuckles are pretty solid until someone breaks them by not properly doing the adjustment job. Trying to adjust them without loosening the pivots and the end bolts (eye bots) puts too much force on them and can break the turnbuckle or worse, an ear off the engine or AC compressor.

What I do:
Spray turnbuckle with penetrating oil
Break loose the locknuts while everything else is tight and spin them out of the way (one is LH thread)
Loosen the end bolts and all the pivot points
adjust
tighten pivots
tighten end bolts
tighten locknuts.