Best order for Exhaust mods (NA)
 

Alright, so I'm saving up to start modding my exhaust. I don't plan on going boosted, but I do plan on full bolt ons. My question would be, what is the best order for doing exhaust? I have A LOT of mechanical experience but not too much on the FA20. I already have a Borla S-type axle back system but I'm planning on moving to the Invidia N1 with a CNT catted downpipe/ovepipe (emissions reasons) and a catted EL header (probably AFE). I know all together its going to be loud as mess and give some gains combined with the CAI I plan on doing (possibly a tune as well) but I don't know which order would be best. Any advice would help. Thanks!

catless uel header, hi flow catted front pipe, and a q300 catback is my suggestion. stay with just a drop in air filter and intake elbow, and make sure to get a tune.

If you plan to go with catless headers and the N1 keep in mind this is going to be very very loud and drone like a sob on the highway.

I have to keep cats on everything because they use sniffers where I live and they also do ECU checks, plus I heard catted cuts down on the drone a little bit.

Maybe im getting soft the older I get but I had N1 with stock everything else and I thought it droned alot then.

I'd do tune > headers > overpipe > front pipe

Stock mid pipe is good, the axleback should be enough to give you better sound over stock, I don't see much value in replacing it with a catback.

Do tune last if you plan on doing a custom tune for maximum gains

I'm likely going to do the tune after so I can tune it with my exhaust/intake setup and get the most out of it without boosting/NO2.

And my Borla is the "factory upgrade" so its kinda weak with the current setup plus the flanges are rusty (nothing else under the car is rusted strangely enough)

I would do a UEL header before anything else and then a tune. From there you can choose from the other exhaust pieces.

Why EL, OP?

If you want EL, do a good catted long-tube EL header - there are a few, and a tune. You can get an OFT and use their free maps to pretty good effect. That will get you most of the gains. See how it sounds with your Borla, and then go from there (louder or quieter) by replacing the axle back or going full cat back (replacing front pipe will make it noticeably louder). I'm running just a catted EL header and axle back, and feel pretty substantial gains. Sounds awesome too.

Equal temperature differential between cylinders and higher top end gains. I have other plans for the torque dip. Also, thats about the only catted variety I can find without dropping 2k on the UEL catted variant I found....

Frankly, if you have to keep your cats, just tune it and go with a catback system you like the sound of and call it a day. Anything else you do will have only marginal power gains and you should really ask yourself if it is worth the cost. The stock exhaust is very good other than the restriction caused by the cats.

Incorrect. I run a catted EL header with a stock exhaust except axle back (which does nothing for power). A pretty remarkable difference in power output according to my finely tuned butt dyno.

Please see quote in my signature and this link http://www.ft86club.com/forums/showp...51&postcount=1. Perhaps you consider the investment of a catted header and install costs (if not done yourself) worth 5hp, but that is subjective and in no way invalidates my statement: " Anything else you do will have only marginal power gains and you should really ask yourself if it is worth the cost."