Welcome to the North American Subaru Impreza Owners Club Monday March 8, 2021
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
Go Back   NASIOC > NASIOC Technical > Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo)

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.

* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Thread Tools Display Modes
Old 01-20-2021, 07:32 AM   #1
Scooby Newbie
Member#: 130690
Join Date: Oct 2006
Chapter/Region: South East
2018 WRX STi
Crystal White Pearl

Default Will changing AEM intake model affect tuning?

Hello everyone! I've researched the forums a bit on this topic and have yet to come to an exact conclusion based on what I've read. I have a 2018 STi that is protuned with the 2015 model of the AEM intake. Since then AEM has released a newer version of their intake with better fitment for the 2018+ models to compensate for the added crash support in the bumper. The 2015 model I have on rubs a lot on this support and the filter is getting bent/worn. The tubing appears to be the same diameter, the only difference being a slight difference in filter size and the MAF is in about the same location. Would this negatively affect my tune enough to cause issues if I were to install the better fitting version? Thank you for the help!
* Registered users of the site do not see these ads.
JKLtdSTI is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 01-20-2021, 09:12 AM   #2
Scooby Newbie
Member#: 518830
Join Date: Sep 2020
Chapter/Region: RMIC
Location: Colorado
2009 WRX
dark grey metallic


My guess would be yes- it will effect your maf scaling- but the question is how much? If the tube has a different bend then the prior one the air flow around the maf wire will be effected.
GeoNV is offline   Reply With Quote
Old 01-20-2021, 10:16 AM   #3
Scooby Newbie
Member#: 508105
Join Date: Nov 2019
Chapter/Region: NWIC
Location: Seattle, WA
2002 WRX Wagon VF39
Midnight Black Pearl


Dom, the creator of the cylinder 4 cooling mod, made a good video about aftermarket intakes on MAF Subaru's.

I suggest watching it.
K3rm1tth3fr0g is offline   Reply With Quote
Old 01-20-2021, 11:13 AM   #4
Scooby Specialist
Member#: 298403
Join Date: Oct 2011
Chapter/Region: W. Canada
2008 WRX Premium
Spark Silver


Manufacturing process could have slight variation between kits for the same car, so if you wanted to get that technical, you'd have to retune even if you replaced a stock intake for a stock intake. I think the better person to ask is AEM themselves and see what their dimension differences are between the two kids.

Originally Posted by K3rm1tth3fr0g View Post
Dom, the creator of the cylinder 4 cooling mod, made a good video about aftermarket intakes on MAF Subaru's.

Best Intake for my WRX? - YouTube

I suggest watching it.
He forgot to mention, in closed loop, there's compensations for this ever so slight variance that this is a nonexistent issue. What he talks about would more so be an issue in open loop though...

However, that being said, I have a metal intake with a ton of other mods and a tune . I monitor the health of the engine with various added sensors including a wideband and never have I ever gotten concerning numbers he suggests I should be getting.

If you want to be that precise with your mods and hardware choices though, have at er. Cost between intake kits are all pretty close.

Last edited by viper_crazy; 01-20-2021 at 11:22 AM.
viper_crazy is offline   Reply With Quote
Old 01-23-2021, 08:08 PM   #5
Scooby Specialist
Member#: 50072
Join Date: Dec 2003
Chapter/Region: South East
Location: TN
2017 STI


As mentioned in the video, what matters is the diameter of the pipe that the MAF resides in. If AEM kept the same piping but tweaked other parts, you should be good to swap to their revised intake.

Cobb did something similar with their SF intake. They initially had the SF intake and box, then released the Redline intake model but kept the pipe diameter for the MAF the same; this made it a direct replacement without requiring retuning if you were already using a tune/MAP for the SF intake.

I would contact AEM support regarding this and would expect them to be able to answer that question.
djoye is offline   Reply With Quote
Old 01-24-2021, 09:16 AM   #6
Scooby Newbie
Member#: 515308
Join Date: Jun 2020

If it is worth changing then it will need a tune, if it dosnt need a tune then it dosnt do anything worth changing to.
benflynn is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 03:05 AM.

Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2021 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.