Exhaust Cutouts

[TimboSHO]

I was wondering if anyone has tried these on a Gen 1 or 2. I have a 3.2 with EH/BBB intake, bigger maf, cams, y-pipe, but with completely stock catback. I'm starting to explore exhaust options, and wondered if anyone has done cutouts. I will occasionally track the car (once or twice a year), but will also be a fair weather cruiser. I don't want annoyingly loud exhaust around town, but if it would help performance on the track, i wouldn't mind the extra noise there.

Would I go with a bigger resonator so that I would still have enough backpressure when i 'cut out' the mufflers from the system?

Opinions? Likes or dislikes if you've tried it?

Thanks!

 

[Dirk37]

I've got one on my car and I absolutely love it!

The low end loss is moderately noticeable but once its gets up around 4000 it pulls quite a bit harder. I have no cats on my car which contributes to the low end loss, but since it sounds like you still have yours that should make up for some of it.

What type of cutout were you thinking of getting?

 

[jayro]

I think Zach had cutouts of some kind on his. He said he picked up a MPH at the strip with them.

I should help with higher RPM's at the track.

 

[TimboSHO]

What type of cutout were you thinking of getting?

All I know is that I would like an electric one right after the resonator. I have no idea what brand is good or anything, that's why I'm asking!

Where is your cutout? Is it manual or electric? Pictures?

 

[Dirk37]

I've heard bad things about electric ones so I actually made my own

A lot of the new Audi's and BMW's have these mufflers that have butteryfly valves on them that open around 4k to give the car a sportier sound.

I just cut that valve out of one I picked up from one of my friends (you could probably find a used one at an exhaust shop for cheap) and welded it on to the side of the catback under the passenger door.

The butteryfly is actuated by a vacuum, so I picked up a vacuum solenoid from the scrap bin at work and T'd it off the intake runner vacuum reservoir, then I ran some wires into the passenger compartment and hooked them up to a switch.

If you get up to about 7k with this open it is probably most ear splitting sounds you'll ever hear

My crappy welds

The donor muffler

Vacuum solenoid

Under the car

 

[SHOdded]

Post a sound clip!

 

[gmail]

Area91 has had them on his 91 plus for awhile that I knew of and said it helped... the sound was insane

 

[Dirk37]

I'll post a clip tomorrow when my neighbors aren't home, they already hate me enough :laugh_ti:

Edit: Might be a bit, snapped one of the y-pipe studs off flush with the rear manifold

I've been thinking about wiring the cutout to switch with the intake runners, that way I'd keep back pressure for the low end and get a little performance boost once it gets up there :woo-hoo:

The one downside to my cutout is that the butteryfly leaks a bit. It sounds like an exhaust leak between the Y-pipe and catback. It's not too bad but if you like a quiet car it can be kind of annoying.

 

[StreetlightSHO]

I've heard bad things about electric ones so I actually made my own

A lot of the new Audi's and BMW's have these mufflers that have butteryfly valves on them that open around 4k to give the car a sportier sound.

I just cut that valve out of one I picked up from one of my friends (you could probably find a used one at an exhaust shop for cheap) and welded it on to the side of the catback under the passenger door.

The butteryfly is actuated by a vacuum, so I picked up a vacuum solenoid from the scrap bin at work and T'd it off the intake runner vacuum reservoir, then I ran some wires into the passenger compartment and hooked them up to a switch.

If you get up to about 7k with this open it is probably most ear splitting sounds you'll ever hear

Wow this is funny, I've been planning an exhaust setup like this when my old mufflers start to go..... Except with the cutout at the rear y, so when it is closed, exhaust flows through a big muffler out one tip, but when open, exhaust flows directly to the other tip.

And I know it won't net much hp if any at all... mostly for yummy Yamaha sounds.

 

[jayro]

All I know is that I would like an electric one right after the resonator. I have no idea what brand is good or anything, that's why I'm asking!

Where is your cutout? Is it manual or electric? Pictures?

Why were you thinking after the resonator? I would think that for a cutout you would be going for maximum flow and would mount it shortly after the y-pipe.

 

[TimboSHO]

Why were you thinking after the resonator? I would think that for a cutout you would be going for maximum flow and would mount it shortly after the y-pipe.

I believe I would still want some backpressure, and I'm not sure how loud I could stand it either.

I do like the idea of hooking it to the secondaries... hmm....

 

[RonPorter]

Don't bother.

They are less than optimal for exhaust flow. The V6 sounds like absolute shyte with an open exhaust, and any power gained (maybe) is at a serious loss on the low end.

The car will feel stronger on the top end because of all the loss lower in the range. Yes, the butt-dyno lies.

Sure, maybe a coupla MPH on the top end at the strip. At the loss of ET. ET is made mostly in the first 60' and the 1/8th.

 

[Dirk37]

I believe I would still want some backpressure, and I'm not sure how loud I could stand it either.

It is pretty dang loud in the cabin with it open where it's mounted now, and you can feel the floor vibrate which is pretty fun

Don't bother.

They are less than optimal for exhaust flow. The V6 sounds like absolute shyte with an open exhaust, and any power gained (maybe) is at a serious loss on the low end.

The car will feel stronger on the top end because of all the loss lower in the range. Yes, the butt-dyno lies.

I do agree it is not the prettiest sound ever. The car does pull a bit more though with it open at the top end, when I first had it installed I ran a few tests opening it at various RPM's and opening it at 5500 you could feel a definite pull. It's not amazing, but it's somewhat better.


I think the best part about it is it makes the driving fast experience a lot more exciting, it feels like your in a straight piped race car instead of a goofy Taurus. Sure it doesn't do too terribly much from a practical standpoint, but then again neither does watching TV, but it's still fun.

I don't want annoyingly loud exhaust around town, but if it would help performance on the track, i wouldn't mind the extra noise there.

If you intend mainly to use it for the track, I'd get something like this:
http://www.summitracing.com/parts/sum-670136/overview/

Then mount it around the where the mufflers Y out so that you have enough backpressure for low end and have plenty of flow for high RPM's. The downside is it's not switchable so you can't blow through tunnels in 2nd gear or scare people on the sidewalk

 

[Gator417]

Well done Dirk. Sorry to resurrect such an old thread, but I think it has some real merit. Those German cars don't have these just to sound more sporty. To do so would be überflüssig und auffällige. They do it to help flatten the torque curve, much like the butterflies on the intake of the SHO.
If its done right, there will be a noticeable gain in low end torque without giving up any top end. Or you'll see a gain in top end without giving up your low end torque. Depends on what the exhaust is tuned for as it sits. First developed by Yamaha (EXUP) they have been on crotchrockets for about 20 years now. You could live with this in a DD if you dumped it into another muffler or ran it further back. Just throwing it out there for you guys to run with.
Gator

 

[AREA 91]

I have been using an electronic exhaust cutout for years. It's fun.

 

[TimboSHO]

I have been using an electronic exhaust cutout for years. It's fun.

What brand? Any details on the setup?

 

[AREA 91]

What brand? Any details on the setup?

Quick time performance from summit racing.
I have ceramic coated headers with a custom Y pipe. The cutout is on the Y pipe. This basically makes it open headers with no restriction from the cat back when the valve is open.
My plus is highly modified.