I was driving my car tonight wanting it to be a bit louder......Not all the time, just when I want it to be loud.

My current exhaust setup is fairly quiet (Magnaflow muffler welded in, Thermal Research Catback). My wastegate is rerouted back into my exhaust, so I don't get that noise either. I was thinking about putting a cutout someplace after the point where the wastegate is routed into the exhaust so that when I "race" or just want to make some noise, I can push a button or flip a switch and make the car 5 times louder. Would doing something like this affect tuning at all? Boost creep? Anything? I'm going back to the dyno HOPEFULLY this week to have the car tuned for 20 psi, so I would like to know if this would influence tuning so that I can have it installed before then.

Thanks for the help!

 

http://www.atpturbo.com/root/releases/release091004.htm

 

With how finicky our cars are, I would definitely tune for the cut-out. It is significantly less resrictive, and couldn't hurt to tune for. I've been planning on doing something like this just so I can have good power, but a quiet exhaust most of the time. From what I've heard, the valved cut-outs always end up leaking, but the people that have them never seem to mind.

 

http://www.jcwhitney.com/webapp/wcs/...0101&langId=-1

Little bit cheaper than the VES, but not as cool.

 

You might want to talk with Steve Kan, he tuned a guy down here using a cut out. The car ran an Apexi single that would boost 14 psi with the cut out closed and 17 psi open.

Jack

 

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Steve Kan also tuned my car with a cutout : )

I'm not sure what you are asking but yea obviously cutouts have been used forever and it works very well. And of course you have to tune for it bro its about a 40rwhp difference on my car at the same boost level

 

Wow! 40whp? What does your car have for exhaust otherwise? I could see if one had a stockish exhaust with a cutout making that kind of power increase, but not a full exhaust like mine. How would the car run with the cutout closed after it was tuned to run with it open? It would still run smoothly, right? It just wouldn't make as much power I assume.

 

Yea it runs perfect with it closed but steve is a maniac at tuning
as soon as you take it off you notice a huge increase in pull it feels great

Um actually my exhaust isn't that restrictive I have a borla XR-1 midpipe and a greddy sound performance exhaust....I LOVE the sound of my exhaust. The cutout is pretty hardcore I only do it at the track but it's cool to run 11s without it cause people think my car is stock until they see the #s up and ****

last time some morons were there and they were like its his 5th run getting 11s in a row I cant believe that rotary is still not blown up LOL you gotta love the ZERO knowledge all these other people have

since your thread is about disadvantages I'll add that it's possible to get a leak where the cutout is since it requires a gasket and it's hard to place it at the right place so it doesnt hit the ground and it doesnt get the underside of your car dirty....

 

The cutout is great in my opinion. I used to run around with stock exhaust with my TO4S setup and have it tuned for the cutout. It ran really rich with the stock exhaust, but I would always mess with people by opening it up all the time. Kind of like going from Stock to Exetremly modified at the flick of a switch. LOL.....
A 30 dollar Cutout pipe and this do the same thing.

http://www.mccordcg.com/mpp/mpp.htm
Good luck

 

Just be carefully with a cutout. Remember our cars shoot flames and I for one wouldn't want flames underneith my car. Depending on were your cutout faces, you would have to be carefull not to shoot flames with a stationary vehicle by reving. You could very well start a fire with some of the chemicals on the road. Just a thought!

 

Oh yeah one more thing on placement. I welded my cutout on the downpipe when it bends to go back to the main cat. you can cut the ypipe that summit sells, and wrap it around the downpipe (mild steel DP) and mig it on and violla it will shoot the exhaust straight down. It was always fun to run at the track like that too. I would stage with full stock exhaust, bring it to 4K for launch, and then open the cutout. It really gets the crowds attention, and gives that HOLY $hit is that car a sleeper feel to it. LMAO!!!!
Oh I miss my Rx7, where is the For sale section again. LOL.....

 

Got any pics of the cutout on your car, Conv. WS6?

 

<rumaging through lots of files> umm........... I know it's around here somewhere. <rumaging through lots of files> maybe this is it...... <rumaging through lots of files>
Welp no luck guys. sorry. Pretty easy install though. Just cut the (29.99 y cutout 3 inch from summit) in half. widen the cutout slightly. Beat it onto the down pipe and use a die grinder to open the hole out on the downpipe after you tack it in place. Make sure the y pipe is opening straight down, and have the electric cut out there for fitment issues before starting your project. I will be doing the same thing to another RX7 I'll be putting together in the future, but it will be a sleeper V8 project with header dumps and even a fake/hollowed out factory exhaust for the rear end appearance. I went alittle crazy with the last rx7 but this next one will be a real sleeper and true feeling hurter.