need an frs experts help please!
 

My good friend has an frs and the other night we got into a little argument/debate...

It started off with him asking what he should do next to it (already has an injen short ram intake and trd axle back exhaust). I said get the header he wants, agency power, and get a cat back with the ecutek programmer and what im guessing is an etune from that visconti guy? Hes down to get the header but wants to get the catback and tuning programmer later on. I said to make those mods worth it he needs a tune, and if his car responds anything like my civic si does to minor bolt ons than it would change the whole car.

Question 1. Does the frs respond well to the basic i/h/e and tune? Enough to justify holding of on the header until he can buy header/exhaust and ecutek with a tune or whatever tuning device he chooses

Then we got talking about straight piped exhausts and he said somebody from cobb in plano Tx said a straight piped exhaust would "suck a valve?" ive never heard that phrase ever in my life but i have heard "float a valve"...but why would a straight piped exhaust hurt your motor in any way?? He said the guys at cobb said the backpressure wasnt good and his motor didnt need a straight piped exhaust cause i guess it would be overkill? Well isnt a straight piped exhaust flow pretty much the same as a catback but just way louder? If both are lets say 2.5 in exhausts? And then he tried telling me that if you took any cat back exhaust and replaced all mufflers and resonators with matching piping that it wouldnt be a "true straight pipe" cause it has bends ? Apparently the guys at cobb have a different definition of straight piped exhaust cause thats whos told him all of this.

Question 2. Is a catback exhaust with no mufflers or resonators a straight piped exhaust?

Last but not least he asked me what i thought his car would put down on the dyno since hes added the SRI. Well i knew since his car makes 200 at the crank stock and is rwd he should lose a little more power than my si and i know on my car SRI's dont really do too well because of past experiences. So after thinking all that i said it might put down about 170ish if it was a dynojet. He disagreed and we made a bet saying if his car breaks 190whp i owe him 50$. And then he told me he had his car baselined at cobb in plano tx and it made 189hp ???

Question 3. is it possible for a stock frs to make that much power regardless of what dyno he was on?

If cobb from plano tx is on here im not trolling or trying to bash in any way but i would like to know who told my friend these weird things and if they are true. Im going to ask to see his dyno sheet later today cause most stock frs's are in the 160's arent they?

End rant.

Thanks for the reply.

But im talking about a straight pipe exhaust not an open downpipe.
If the effects are the same for both than my question is answered.

My buddys evo 9 has been running a straight pipe for a while and hasnt melted a valve or anything, but thats not an frs/brz.

Even an open dump off the header is way different than running without a header at all... the Evo is a different beast too because it has a turbo in the way which will also hold heat and create backpressure.

As for the actual questions...

1) They do respond well, most of the gains are from the header and tune though. There are smaller gains from a good intake and header back exhaust, but not nearly as much as from a good header. Tell him to look around at dyno charts to see what headers are making good gains and not to base the decision off price alone. It will make more power with just a header, but not nearly as much as header + tune. IMO, he should get rid of the injen intake and put the stock airbox + upgraded panel filter in, or upgrade to a true CAI (FA20club, perrin, etc). He also needs to replace the overpipe and front pipe if he wants to free up more power, there's more power lost to those parts stock than the stock cat back exhaust.

2) To me (and anyone I know) a straight pipe exhaust is an exhaust without any resonators or mufflers, but can have bends. I think your friend is reading too much into what people say.

3) There's no way he made 189whp on a properly calibrated dyno with just an intake and axle back exhaust. Dynojets will read higher, but not that much higher. On average it seems that we lose about 18% from crank to whp, so to make 189whp that would be about 223 crank, and there's just no way he picked up 23hp from a SRI and whatever cat/axle back exhaust he actually has. Not many people have cracked 190whp with a good CAI, header back exhaust (the overpipe/front pipe make a big difference) and tune without running E85.

For the record, Cobb has no parts available for these cars and from what I've heard have no plans at all to support them so why is your friend talking to them? There are many shops that have lots of first hand experience with these cars that will give him far better answers.

PS - the north american TRD exhaust is a cat back, not axle back, does he have the JDM axle back with quad tips or the north american cat back with D shaped tips?

The old wise tale is that if you run open header or if you're retarded enough to try it open heads that the cold air between pulses causes premature valve seat wear. I've been running open headers on my Mustang drag car for awhile and of course it's fine, straight pipe exhaust while doesn't have the back pressure a catted and muffled exhaust does still keeps residual heat, especially close to the header. It's fine...

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Agency headers are crap and have not been shown to make many power. He should go with one of the several others that do make power.

Why isn't he on here doing the research himself?

Even an open dump off the header is way different than running without a header at all... the Evo is a different beast too because it has a turbo in the way which will also hold heat and create backpressure.
Ya when he showed me his intake i thought he could have bought a better performing one like a cai. I had a kn SRI on my si and i should have bought one of the 3.5 inch cai's from the site vendor. Ill tell him about the front pipe and over pipe. He asked me last night if he should do the header or red tail lights...i said red tail lights

Exactly. As soon as i said that he said its not a "true straight pipe" but thats not even what really threw me off...the 189 did lol

Thats what im saying! If it had been me i would of asked why it read so high...oh and the 189 was stock with 40 miles on the car...ya, doesnt seem right to me

I dont really know why lol i know at his work theres 3 subarus wrx's and sti's so they probably got him into them, but i also noticed the frs/brz isnt on their website. I was trying to tell him to get his car tuned by that visconti guy cause he seems like vitviper at 8thcivic.com

he told me it was an axleback and i was assuming it was also cause his tc had a trd axleback. I didnt know trd made catbacks but it has D shaped tips so its the cat back. Explains why it cost a grand

Thank for the replys everyone!

Which ones do? I will let him know.

Thats a great question. After having this conversation he concluded with "if youve done any research the stuff im saying would make sense"...well it doesnt, so now i joined to do my research i guess lol

Its cause he talked to some people at cobb and now he is set on what they said, and anything different is bs. So far the "people" that he talked to are sounding ignorant.

I told him to join the forum but obviously he hasnt cause he has his own sources, but hes missing out because so far you guys Have been awesome with helping me and i dont even own an frs!

Tell your friend to talk to a shop that actually has experience with the car... nothing against Cobb, but they don't offer a single product for these cars, so why would you go to them for advice?

If he wants to kill two birds with one stone, tell him to get the FA20Club CAI and header, both are proven to make good power and won't break the bank.

No offense to your friend, but it really doesn't sound like knows what he's talking about at all. The north american TRD exhaust is clearly a catback, the midpipe takes a different path around the diff to the muffler.

sounds like two 15 year olds are fighting

Thanks! Have a great day:happy0180:

Heh, just recently did this on my FR-S while toying around with my exhaust. Had a bad gasket between the overpipe and front pipe so I took the opportunity to listen to the noises the FA20 can make. I was in love and I'm trying to find what kind front pipe will give me something similar to that sound.

Nice to know though that I probably didn't kill anything :)