I'm putting exhaust on my 90conv and I wonder if there are any side effects of using large diameter exhaust such as apex GT, N1 or similiar greddy models. I heard that rx's need backpressure to operate properly. I also heard that my car, being a 1990 model, doesn't have that need and that larger diameter exhaust would be fine. The only reason I ask is that I plan on doing extensive modifications and I don't want to buy 2 cat-back systems.

if step one is just the cat back then any of them are fine, it doesnt do enough on its own to really hurt or help much



mike

on your n/a all a catback is gonna do is make the car really loud.....

step one is already done, bonez single high flow cat. step 2 is in the mail, RB header. and step 3 goes in friday which is a cold air intake. could this cause probs?

you should be fine...get the N1 or corksport...they are nice yet cheap

hopefully it won't be N/A for too long -=) I just have never played with turbo's before.. gotta talk myself into taking the dive -=) Thanks for the info. Maybe I will just weld on a sewer pipe and put stickers on my car instead.

Take it from another vert owner with aftermarket exaust, its too loud and not worth it performance and money wise.



Im hoping that changin my mufflers to Racing Beat mufflers this spring will quiet the car down, otherwise Im going to go insane with this ******* car, lol.

mine was makin me crazy when i had headers and presilencer but oem y pipe and mufflers.



after putting the rb mufflers and y pipe on the car sounded quite sexy. Rob, I think you'll like it with the RB mufflers.

God I hope so, had RB sold stainless steel mufflers when I did the exaust originally I would have went with them. Instead I went with the Borla.

I have heard a racingbeat system with a Bonez converter on 13Bace's N/A rx-7 and I liked the sound, so now that RB sells the stainless I will go with them this spring.

God I hope so, had RB sold stainless steel mufflers when I did the exaust originally I would have went with them. Instead I went with the Borla.

I have heard a racingbeat system with a Bonez converter on 13Bace's N/A rx-7 and I liked the sound, so now that RB sells the stainless I will go with them this spring.[/quote]

i was also going to go with that setup...plus a header...will the header make the car any louder

header will make it louder...



Vosko had header w/stock exhaust on his 89GTU...



I had bonez high flow cat and Apexi N1 catback on my 91 n/a...



his was louder

on a N/A rx-7 if you go too wide you will lose back pressure, if you don't have enough back pressure the 5th and 6th port actuators won't open causing you to lose 25 horse after 3500 rpm. honestly I wouldn't go any bigger than 2 1/4 or 2 1/2, I have 2 1/4 on mine with straight pipe exhaust, intake, and air pump removal with 5th and 6th port wired open and I run really well, but it is really loud, if you're not looking for loud, leave in the air pump and don't hollow the cat and it will sound good.

also nimrod, where and for how much did you get your rb header for???

Depends on the condition and type of exhaust you previously had.I know this one guy here that has a Series 5 N/A and he said he was able to feel it when he put on his catback system.

I didn't really feel any difference with the catback but then again there was nothing wrong with my stock cat back, I just wanted aftermarket.



If you have for example a header into a straight pipe with no cats into an N1 single, you will likely have problems with your 5/6 ports opening and lose some low end power like Diablo was saying.... not to mention it would sound ridiculous.



I remember driving with an open header on some back roads and it was so loud I was damn near deaf. When it backfired, it sounded like a bomb went off.......now that is the ultimate perfomance, I'd say I was pushing 220 at the wheels... maybe 230 since the header was a JDM Monza https://www.nopistons.com/forums/pub...#>/biggrin.png

Yeah you should see Vosko's GTU now...my roomie bought it and it's louder than anything I have ever heard...Runs 15.4 at the track all day long, with no mods besides exhaust. Springtime should be even faster https://www.nopistons.com/forums/pub...IR#>/smile.png

I had to cancel the RB header after I found out how long it was and sat there staring at my new cat thinking how I could possible cut and re-weld it to fit. I already ruled out Apex and i'm ordering the SS RB exhaust. I know it isn't gonna give me any power but I don't want anything stock on this car. Plus if I don't spend my money on my car my girl will want it all -=)