Originally Posted by ThatYeti (Post 3523352)

Realize I'll be in the minority but have a catted FTspeed header I'll be installing and the car is a stock '17 with a JR oil cooler, Grimspeed airbox, and an OFT stage one already but haven't been able to find which stage is right to use. Heard/read that stage one is still sufficient given the limited flow from the catted header but swear I'd seen it listed on a thread a while ago that stage 2 was the correct tune once you had a header even if it was catted.

Tried the search function and didn't have much luck as there's too many threads that reference all of this (most of which are long for sale threads) so I appreciate the help in advance.


Thanks

Originally Posted by spcmafia (Post 3523513)

You would need a Stage 2 as a base but will definitely need a custom tune from Steve99 or Wayno because of the Grimmspeed Airbox.



Stage 1 Hardware Requirements:

• OEM header. *Any exhaust modifications after the header is also compatible
• Stock Airbox (with or without aftermarket drop-in panel filter)
• Premium grade fuel

Stage 2 Hardware Requirements:

• Aftermarket CATTED header. *Any exhaust modifications after the header is also compatible
• Stock Airbox (with or without aftermarket drop-in panel filter)
• Premium grade fuel

Stage 2+ Hardware Requirements:

• Aftermarket CAT-LESS header. *Any exhaust modifications after the header is also compatible
• Stock Airbox (with or without aftermarket drop-in panel filter)
• Premium grade fuel

Stage 2+ (E85) Hardware Requirements:

• Stock OR Aftermarket CATTED OR CAT-LESS header. *Any exhaust modifications after the header is also compatible
• Stock Airbox (with or without aftermarket drop-in panel filter)
• E85 fuel ONLY!!

Originally Posted by ThatYeti (Post 3523523)

Everything I'd read showed the grimmspeed box as a direct replacement for the factory box (only did it to get a little extra space for the oil cooler) and haven't had any issues running the OFT stage one for a bit now. Did you have issues running it?

Originally Posted by spcmafia (Post 3523524)

If I remember correctly, there is a tune that is specific to the Grimmspeed box. I'll find it. I didn't invest money on that piece of hardware. I just use an aftermarket filter and inlet tube.



You wouldn't necessarily run into problems by just using the Stage 1-2, but you could possibly be missing out on a couple extra HP because the tune is not optimized for that box. You should get in contact with anyone who does custom tunes, trust me, it is worth it, and you won't have a generic tune, you''l have something that it is optimized for every aftermarket part you have.

Originally Posted by ThatYeti (Post 3523526)

Fair enough, though I may not be keeping the airbox long term as it's rubbing one of the hose end nuts where it connects to the oil filter spacer so I may just stick with a shelf tune til I sort that out so I'm not wasting money on multiple tunes.

Originally Posted by spcmafia (Post 3523528)

BTW, didn't realize you're from CT! What part?!



You can always switch back to stock, sell your GS box, get an inlet tube and K&N filter for $120-ish, switch to Stage 2 once you install your headers, if you haven't done so. I also run catted headers and even a double resonated Front Pipe. Rather not worry about emissions and salty cops.

Originally Posted by ThatYeti (Post 3523523)

Everything I'd read showed the grimmspeed box as a direct replacement for the factory box (only did it to get a little extra space for the oil cooler) and haven't had any issues running the OFT stage one for a bit now. Did you have issues running it?

Originally Posted by spcmafia (Post 3523524)

If I remember correctly, there is a tune that is specific to the Grimmspeed box. I'll find it. I didn't invest money on that piece of hardware. I just use an aftermarket filter and inlet tube.



You wouldn't necessarily run into problems by just using the Stage 1-2, but you could possibly be missing out on a couple extra HP because the tune is not optimized for that box. You should get in contact with anyone who does custom tunes, trust me, it is worth it, and you won't have a generic tune, you''l have something that it is optimized for every aftermarket part you have.