I now have a 3 inch exaust with no cats and a Rb muffler. My new turbo has a 4 inch outlet and Im wondering if I should run a 4 inch all the way to my muffler or just run it to my 3inch mid pipe? I would like to keep the RB muffler but if I go 4 inch I might need a 4inch muffler if thats even possible.

 

There is a company that makes a 4inch exhaust....possibly HKS but don't quote me. I actually remember someone selling one on here not too far back. Possibly its still available. Might want to check the parts for sale section. I have the same situation you have. I am having a dp made that transitions to 3 inches. I've heard 4 inches is super loud and I'm not really into that

 

hey channon...i saw two on ebay a couple of days ago...i cant remember the company tho.

 

The dP is being made I can either make all the exaust 4inch or just the dp. I wish there was someone that has already been in my shoes and knows the best rout?

 

how much power are you shooting for? what kind of turbo is it?

 

i have the hks 4" ti exhaust, also greddy made a 4" also. it's expensive though.

 

Hi Guys, I have a TRUST Japan Ti 4" Mid pipe and cat back.. it's LOUD AS **** ! i get headaches all the time .. it's really a pain sometimes, gotta' keep some Tylenol in the glove box all the time. The drone shakes the whole car !

 

Hi.. do you think you can put me in touch with the folks making your 4" DP ?? I need to get one as well.

please PM me.

3G7

 

I got a complete (turbo back) 4" mandrel bent exhaust on my setup. Corksport is fabricating it for me.

 

I have the HKS Ti 4" too...........WHAT

 

The turbo is a borge and warner ht-300 and Im shooting for around 600rwhp at 25-30psi. The turbo has made the power on a rotary before I just dont know if that was with a 4in exaust or not. I think Im just going to plumb my 4in dp into my 3in exaust and try that. To everyone running the 4in exaust what kind of muffler are you using?

 

I priced some mandrel stainless steel and It is suppose to be the best but the price was out of this world and if you are doing a exaust system with that I like to see a price? I wanted to make my manifold out of this but my funds were to low. I think we are talking about the samething.

Channon

 

i think you only really need 4 inch exhaust if you are making upward of 800 rwhp. If you are making 600 to the wheels and just use a 4 downpipe, you will be fine. Its not worth the extra ton of money for as little as 2-3 horsepower, if that. I guarentee you wont feel a differencen anyways. with 600 rwhp you got bigger things to worry about then more power. Traction is key.

 

YOU got that right traction is the key and its going to be hard to get the car to hook with 600rwhp. I think Ill just use the 4in Dp and 3in exaust.

 

just buy custom piping and fabricate one yoruself.

 

dose apexi make a r-95 for rx7's? they also have the hyabusa model..i think both are 3.75 inch piping...but both applications were for the evo

 

tubing

http://www.jegs.com/cgi-bin/ncommerc...17&prmenbr=361


mandrel bends

http://www.jegs.com/cgi-bin/ncommerc...27&prmenbr=361

 

Channon, I'm glad to see that your FD is about up and running. From all that I know the 4" DP and 3" exhaust will do you just fine for 600rwhp. Let me know if there is anything I can help you with. Sorry I couldn't find you a 20B in time. Though you never did PM me back. Laterz.

Zach

 

If anyone would host 2 small vids..you will hear how loud it is .. plus .. see the nice flamage.. I'd posted these vids before .. but lost the links..

PM me hosters..

 

Quote: "Hi Guys, I have a TRUST Japan Ti 4" Mid pipe and cat back.. it's LOUD AS **** ! i get headaches all the time .. it's really a pain sometimes, gotta' keep some Tylenol in the glove box all the time. The drone shakes the whole car !"

Try the RX7 Store's resonated midpipe, it quieted my open exhaust to neighborhood-friendly, police-unsuspecting level. Just my 2cents.

 

Check out deisel shops. They specialise in large diameter mandrel bent exhausts, so are a great place to get bends and piping for realtively cheap compared to some of the name brand companies out there.

 

with that power level i'd go 4" as far back as you can...

 

How about this Im thinking of staying with the 3in exaust but building in a cutout so I can run open exaust when I want? This way I can still keep the quiet 3in and have all the power of open exaust. I aslo need to know the best place the plumb wastegates back into the DP?

Thanks Channon

 

If you're going to do that, why not have a 4" downpipe to the cutoff to the rest of the 3" system?

SPOAutos started a thread about cutouts, it should be further down in the single turbo section or possibly on the second page. It may be of use to you.

 

i'm actually selling my 4" hks exhaust if anyone interested. i had it post on the FS section