spreeleon

Hi all,

i just got back my 3.2 1988 after getting a stock cat and dansk sport exhaust installed in order to pass cali smog. Before the install i had a premuffler and some custom exhuast. It was too loud but i enjoyed the pops and burbles on throttle lift off. Now with the dansk its awfully tame and i have absoultely zero pops and crackles. My 996 with pse sounded much much louder and nicer. Any suggestions? I know mechanic had to make car run less rich to pass smog is there something i can so tunjng wise to get thiose burbles?

Thanks!
leon

Jherriott

I think the cat is going to kill it. I had the Fabspeed pre-muffler and popped the cat back on for my final smog test, it was like night and day. Car sounds so tame now... I'll be taking it off next week, pretty easy swap really.

spreeleon

thank you! Did you have to jack up car to replace the cat?

also, you didnt have to retune the fuel and air mixture to get the pops correct? Just simple swapping of the cAt gave you the pops? Do you know of any of premuffler that is known to give the most burbles?

premuffler and straight pipes are basicAlly the same?

tha ks!
leon

spreeleon

Between a premuffler and bypass test pipe which ones gives the most burbles and raspiness sounds?

thanks!
leon

Jherriott

Hey Leon,

I find the best pops and burbles come from the earlier CIS cars! haha

But seriously there is a difference between the two. The first time I pulled my cat I used an original cat and punched out the internals and got it all pretty with ceramic coating. It seemed louder, but not too bad. It had some pops and burbles but mostly a more pronounced sound at WOT.

Last year I went with a Fabspeed euro-bypass to lose some of the weight that I was carrying with the cast iron lump from using the punched out cat. The internal design helped keep the exhaust flowing rapidly, and the sound levels really increased.

I would say that I still don't have that lovely sound that a CIS 930 has tho

Jase.

Amber Gramps

I've got the stock cat with the bisimoto pulse chamber and have fantastic fireworks on decel.

Click the link, play the video, listen until the end. ....oh, and ignore the burnout...

http://forums.pelicanparts.com/porsc...ml#post9134684

grgallo

have an '87 with a Dansk Sport Muffler. love it, get great sound; GROWL AND RASPS... also have a cat bypass, so I'm thinking it's the cat. I'm out East we don't smog test 30 year old cars, we are polluters!

spreeleon

awesome looks like i will be tryjng to throw back on the cat straight pipe that car came with and had tons of pops and burbles. This stock cat really tamed everything.

Like i said i have dansk sport 70mm one in and one out with that stock cat and i get absolutely zero pops. None whatsoever unless im getting totally deaf.

thanks amber i will look into thise bismotos as well!

spreeleon

Great to hear...so I drove my car some more over the weekend. Again mine is a 1988 with new stock cat and a new dansk sport muffler one in one out 70mm. I got absolutely zero pops. Sounds like you also have the Dansk sport but instead you have a cat bypass. Which cat bypass do you have? My car initially came with a cat bypass without any branding or labels on it. It looked like decent welding job and solid material so I'm just going to through that one back on instead of the stock cat. I would think that different cat straight pipes are all relatively similar as it's mainly just a straight pipe.

grgallo

I have FVD Brombacher cat bypass, growls and raspiness and deep but not over bearing, I can't say there are lot's of pops, sound is subjective and to each their own.

spreeleon

Was the Dansk sport much louder than stock muffler for you?

1stgear

I have a Fabspeed RSR Header Muffler System with no cats and get ZERO pops or burbles. I think the car is running too lean. Is there a way to play with the air/fuel mix?

Trakrat

I have a Fabspeed RSR headers, minus any exhaust... and other than the occasional backfire pop, I don't get any burbles...
I can try to coax a burble if I feather the gas while decelerating, but its rather quite... but nothing near as awesome sounding as you would expect from a something with a set of Webers.

spreeleon

sooo does anyone know why some of these cars burble non stop and others even with rsr headers dont at all??

Amber Gramps

AFR. Air Fuel Ratio. Cars that are too lean simply don't have unburned fuel going down the tubes.

Prove me wrong...



Just my theory anyway.... I think some cars have been so leaned out to pass smog that they run hot and they run lean and there is zero unburned fuel in the exhaust. My car runs so clean that I can run big injectors and still have stupid clean test results.