Dynomax exhaust plan - Toyota Nation Forum : Toyota Car and Truck Forums

1991toyrolla · 06-24-2009, 11:13 PM

Hello All,

O.K., Here is the plan. After consulting with a custom muffler shop for exhaust ideas on my 34,000 mile front wheel drive Corolla sedan DX I will leave the original catalytic & the resonator pipe.

Where the pipe goes over the rear "axle" the shop will install a y-pipe & run a pipe under the spare tire section towards the drivers side. I am thinking of running 2 Dynomax mufflers (part# 17704) which ebay sells for $26.95 each. They flow approxamitely 30% over stock. In my opinion, by leaving every thing else stock this should not affect the performance. If anything it should breathe better & not make that "dreaded fart sound" that I don't want. Sorry for harping on this subject but it is really important to me & I would TRULY APPRECIATE any input. Thanks.

AstroVannin · 06-25-2009, 06:20 PM

Dual exhaust ???

Terrible

Createdtoburn · 06-29-2009, 01:38 AM

Yeah dual exhaust on a 4 cylinder is really pointless and doesn't really do anything more then one muffler would. Especially when you run 1 pipe down then split into two. Sound wise it would make a bit of difference, but performance wise not really. Now if you had a V6 and ran "true-dual" exhaust with two completely separate pipes with like a X or H pipe in the middle, then it helps a lot and sounds real nice (usually).

But........

you dont. ;-)

1991toyrolla · 06-30-2009, 02:23 PM

Valid points indeed, It helped me decide to keep it as a single exhaust. I ordered a a dynomax turbo muffler to replace the OEM one. It is as close as possible to the OEM muffler size. I know it provides better flow & I HOPE it does not sound ricey. Any experience out there with this muffler?

ae92boi · 07-02-2009, 02:00 PM

is it just the muffler or theres piping included?

***REN69*** · 07-03-2009, 02:00 AM

save your money, exhaust will only give you the most a 2hp gain, and that's of course doing full exhaust with a better header and intake included.

Spend your money on suspension and wheels.

ANY exhaust that's not OEM will sound ricey.

1991toyrolla · 07-03-2009, 09:16 AM

You are right REN69. But, since the tip of the OE ehaust is bent up at the base & the muffler is rusted there (the rest of the exhaust system appears showroom new, either my grandma or I apparently hit something) I decided to replace it with a Dynomax Turbo muffler, cheaper & better looking than the OE. The part # is 17731. If it ends up sounding ricey, I will install an OEM one instead & give the Dynomax to my friend who LIKES noisy, ricey exhaust.

I've been told they are not noisy. I had already ordered one before your reply that is almost the same size as the OE muffler (same length, about one inch narrower & one inch lower) & I will install a stainless steel oval tip & call it a day.

As for suspension: KYB GR2's, eibachs, & 15 x 6s with 205/50r15, when I can afford it.

daemonside · 07-03-2009, 11:00 AM

I'm going to have to disagree with you Ren.I hollowed out my cat and put it back in with stock muffler and all and it sounds wonderful, not ricey at all. As for performance there wasn't a huge gain, but it definitely runs much smoother now.

1991toyrolla · 07-04-2009, 02:34 PM

Hello daemonside,

I have a few ?'s:
1) I don't understand what you mean by "smoother". Does it mean the vehicle shakes less? Feels more responsive, is it quicker on take off or top end.
2) Do you know if you lose backpressure by removing or hollowing out the cat?
3) Was it easy to unbolt & reinstall?
4)Does the exhaust feel more free flowing?

I may just do this instead so that is the reason for my many questions. Thanks

Ghostyman · 07-04-2009, 03:40 PM

Quote:

Originally Posted by 1991toyrolla

2) Do you know if you lose backpressure by removing or hollowing out the cat?

Yes, you will lose some backpressure.

You don't want backpressure. That is an internet myth.

1991toyrolla · 07-04-2009, 04:15 PM

Hello again,
So, It IS OK to hollow out the cat or weld a pipe in place of it (either one will cost me $20 BTW) & this will not hinder the performance (if anything improve it slightly) & not sound ricey? Thanks

RobMilkshakes · 07-04-2009, 04:55 PM

yes it increases flow and the sound will increase some. after all instead of the catalyst material suspended inside, its just an open pipe.

Ghostyman · 07-04-2009, 05:06 PM

Quote:

Originally Posted by 1991toyrolla

Hello again,
So, It IS OK to hollow out the cat or weld a pipe in place of it (either one will cost me $20 BTW) & this will not hinder the performance (if anything improve it slightly) & not sound ricey? Thanks

I hate to be the guy saying this but leave the damned cat in place. You drive a Corolla, not a sportscar. Catalytic converters do a lot to reduce tailpipe emissions. Removing yours is going to make zero noticeable difference in your car's power while jacking up your emissions immensely. Don't be that guy. Stay with your initial post: "I will leave the original catalytic".

Also, the cat does a lot to quiet the raspy sound associated with "ricey" cars. When I removed the cats on my MR2, the exhaust note became a lot harsher.

RobMilkshakes · 07-04-2009, 06:01 PM

I second that actually. I debated putting an exhaust on mine when I had it but decided against it just because I wanted to hide the fact that it would struggle to go up a hill.

Ghostyman · 07-04-2009, 06:58 PM

... and I don't know about you guys but to me there's few things sadder than a loud exhaust on a slow car. Shows a type of delusion on the part of the owner. And earns them a lot of laughs behind their back (and sometimes to their faces).

I wish the exhaust on my MR2 was much quieter but I'll live with it because I actually got significant gains from it.