Hello, I’m Jonattan and I have a 2010 G37 Coupe A/T. Currently the only “significant” mods I’ve put on was a Beluga Racing Axleback Exhaust and K&N air-filter drop-ins. I’m thinking of putting an ISR y-pipe, Tein lowering springs, Z1 hfc, Z1 cai, and tuning it and calling it a day. My goal with this build is to max out my hp but with some cheaper options because I’m currently in High school and can’t make that much profit. Any ideas for this build or tips?

 

No headers?

 

Drop ins, full cat back, test pipes and a tune. That should put you in the 300WHP range and be somewhat cost effective. In my experience with this platform, if you go cheap, you are sacrificing fitment, sound or both.

 

I would but there’s no way I could do it myself and going to a shop would cost way too much.

 

Well with the dropins and axle back I’m approximately pushing 290-300 so with those mods I’d probably go close to 320. I have questions though. Is it worth it getting a cai or are my dropins better? And if I put test pipes will it stench up my car? I can afford some of these other mods but it’s going to take a while since I’m in high school. This is just a starter build but I’m trying to get this done before my senior year ends.

 

I'm not sure if drop ins are better but that's the route I would recommend. As far as test pipes go yes they will smell plus you will have rasp if they dont have resonators

 

Those guesstimates or has the car been on the dyno? No way of knowing where you are until it's strapped down. I have CAIs, ported upper IM, testpipes and a full exhaust and made 282whp before tuning. Without the tune, your car isn't going to reach it's potential; no matter what you end up going with.

Drop-ins are cost effective and should net around 10whp alone (dyno proven). If you want to keep the build cost friendly, keep the drop-ins and replace the bendy straw section of the intakes with Z1 silicone replacements. If not, and you have an extra $400 to blow, Stillen or Takeda are your best bet to keep it cost friendly. Admin intakes and a few others that are 3'' but they cost a premium. Test pipes are going to make the car stink; possibly throw CEL codes. Being that you are in HS, I recommend going HFCs. It'll reduce the smell a bit and the chances of throwing codes drops; while only sacrificing 2-3 hp.

Your axle back will need help. The stock system is a bit restrictive @ < 2'' in diameter. Since you already have an axle back, Picking up a Motordyne Y pipe would be your best bet if you go with test pipes. If not, you're going to get rasp city. Then, you can go to a shop to have a mid pipe made. Shouldn't be but $200.

The main thing you want to focus on, after you get your bolt-ons, is the tune. That's where you're going to gain 30+ hp. Make sure you go with a trusted tuner who has a positive track record. Tune is going to cost you $900+.

Before all that -- maintenance. Fluids and plugs are a must.

 

I watched some videos on test pipes and I think I’ll go with that. You save money compared to a hfc and I do want my volume to be louder as well as my pop ands bangs.

 

I’m just guessing with those numbers because I know my car makes at least 270-280 whp so I’m assuming I’m around 280-290whp with those mods. I’m definitely going to get a tune and I’ve contacted a trusted tuner in my area and I know how much it’s going to cost me. Honestly If I have the money I’ll go with cai, it just depends how long I have left in HS. I think test pipes are the better route because apparently they’re cheaper and I do want that extra hp even if it sacrifices the stench. Do you recommend a catback? Because I’m thinking about getting a single exit ISR Catback with some extensions. It’s really cost friendly and it’ll definitely open up my exhaust and provide more power plus it’s a single exit. I think a cat back, test pipes, cai, and a tune would be a great combination.

 

Cat-back is going to free up tings a bit but it's going to add to the diving experience more or less. Probably 7-10 ponies over the stock system. Try listening to sound clips at different RPM ranges of the set-up you're considering. I personally can't stand any rasp where some people don't mind it. It's your preference but I can almost guarantee test pipes will induce a raspier sound unless you go with a resonated product.

 

Cat back is way too much for me, I compared prices and I’m saving money without it. I’m just going to go with a y-pipe, non-resonated test pipes, a cai if time permits, and then finish performance mods off with the tune. Everything just depends on time and how much I’m making so we’ll see.

 

Damn, wish I had a G in highschool lol.

 

lol right? I was rocking a 118hp Mazda. Only thing in that price range with any type of performance would've been a Civic Si. Unfortunately, didn't know how to drive stick at the time and wasn't bitten by the bug until a few years later.

 

I'd go with HFC just because I'd be worried about throwing a CEL with those test pipes. I've had test pipes on other cars and it can be a headache. I'd recommend getting a Y pipe and have a muffler shop build a midpipe because your car will sound raspy with just the test pipes. K&N drop ins and silicone tubes work pretty well also.

 

go with some art pipes from motordyne, i feel the broke highschool kid struggle but im now transitioning to a broke college kid LOL