Well I am going to be making my gf a custom true dual exhaust for her 89 gtu. I plan on getting the RB dual outlet header (I believe its called a road race header) and I understand it puts it into two 2" pipes. from there I will run 2" pipes all the way back to the dual corksport mufflers (witch actually are 3" inlet pipes) all in all it should cost about 500 plus shipping and install.

My questions are...
for what I want done (pipe bending and welding some flanges on) rougfly how much is it going to cost to get it done?

And is it okay to run the 2" pipe to the 3" CS muffler? if its not then does anyone know of a dual outlet header that has two 3" pipes? is 3" even neccisary in a true dual setup?

Where do I mount the O2 sensor in a dual outlet header? and is there a mount already there on the RB on?

From people that have true dual and have no cats or presilences is you exhaust annoyingly (<---don't think thats even a word) too loud? and by adding silencers to the corsport mufflers will it help out alot?

And if I have to add presilencers what ones do you recomend and is there enough room to add two of em? (main reason I don't want them is because they are spendy specialy for 2!)

well I guess thats about it for now hehe guess that was alot of questions huh? sorry bout that. I will appreciate all the help you guys give me.

 

the 3'' header would just be huge over kill unless you have a ported engine. The exhaust ports on the engine itself are like under two inches, so i think 3'' headers are going to be hard to come by. If you are going to run a corksport exhaust without any cats or presilencers, the car will be LOUD. like you'll pullout of your driveway and all the neighbors will cover their ears. I do know that corksport has the silencers availiable, i would seriously invest into two of those.

 

I don't know if CS has them avail right now but I herd that they are working n some that will be avail soon....

cool thx for your input, anybody wanna take the rest of the questions?

 

No need to use 3".. you'll lose power anyways, plus you need smooth reducers.

2" dual is the best

You will need pre-silencers. It's just too harsh without them

With the silencers in the corksport muffs, it'll still be sort of sharp and very chainsaw-ish.
The pre-silencers don't quit it down a lot, they just smooth out the tone considerably!

 

okay what presilencers should I use? cheap would be nice

Could I use a couple of those dynomax mufflers?