Subaru Forester Owners Forum banner

2015 2.5i UEL headers and other upgrades

28K views 54 replies 16 participants last post by  ssssssantimonio 
#1 ·
I have a 15' 2.5i. I have slowly been doing upgrades to it. I really want UEL headers. Anybody know of anyone who makes them? Also I am considering an Al. crank pulley, any recommendations there? Was looking at Grimmspeed. From what have seen they will work even though its listed as EJ25 compatible. (what is the difference between the motors?)

Right now I had SSDs intake, axle back exhaust, and front strut brace. Also have 20mm STI rear sway bar and Megan racing rear control arms.
Just ordered a throttle body spacer from Japan.

I plan on getting lowering springs, adjustable sway bar links, the AL crank pulley, UEL headers, an AL flywheel, and possibly new cams.

Anyone with information please let me know.

Thank you.
 
#2 ·
You'll probably need to have the UEL headers custom made. I don't anticipate anybody mass producing them. Perrin has a few parts that are compatible, including the crank pulley. I'm not certain which flywheels or clutches are compatible, yet. I would suggest holding off on installing cams and the TB spacer until somebody has the ability to tune the FB25. I hear we're getting close, but it is probably a few months away, yet.
Good luck and please keep us posted on your build!
 
#3 · (Edited)
From my research, plenty of ppl say that lightweight crank and flywheel aren't worth it. Regardless, I read that the Grimmspeed and Perrin cranks for BRZs are interchangeable with FB20 and FB25 (I found an example on a legacy forum).

As far as UEL, there is Rallisport Racing, but be prepared to pay $800+ and then wait 12+ months for your product. I recently contacted a local fab shop that has made custom BRZ headers and done lots of other custom exhaust work, so maybe I'll be able to give you a number to compare your local shops to. If you really want UEL, I'd say find a good nearby auto fab shop with plenty of picture to see good welds, etc, and still be prepared to pay $800+.

As far as tuning, Throttlehappy is ready. You just need a tactrix openport, and then Throttlehappy's pricing for a tune is really reasonable. It's not a dyno tune, but road/data-based tuning is still pretty good. After you get the tactrix, just message him via the Throttlehappy facebook page; he was really quick to respond to my inquiry (I haven't gotten a tune yet, still just sitting on my tactrix waffling over my CPO warranty).


EDIT: If you're interested in UEL this thread at NASIOC is a pretty good read. I thought to link it because at one point the Rallisport Racing guy (1 man deal/shop) notes some differences/similarities between the FB20 and EJ25 n/a header designs (as far as engine-header fitment).
 
#15 ·
Regardless, I read that the Grimmspeed and Perrin cranks for BRZs are interchangeable with FB20 and FB25 (I found an example on a legacy forum).
I just searched the stock pulley on Subaru's parts website and found that the crank pulley part number for the Forester 2.5i matches the part number for the crank pulley for the BRZ.

PULLEY-CRANKSHAFT .
This genuine part fits your 2015 Subaru Forester Base 2.5L 6MT .
-E/#0048495
E/#0048496-
Stock Code 12305AA370 ; 12305AA350; 12339AA000

PULLEY-CRANKSHAFT .
This genuine part fits your 2015 Subaru BRZ Premium .
-E/#0048495
E/#0048496-
Stock Code 12305AA370 ; 12305AA350; 12339AA000

Just thought I'd share my findings.
 
#5 ·
Thanks for the info. I want to increase power but I love the subaru rumble. I have a few fab places by me that I am going to go check out. Any other recommendations for upgrades?

This is my first car that I have put time and effort into modifications and upgrades and I am hooked.

Anyone have experience with RSR springs? Or pictures of their Forester lowered?

Thanks again for the advice! Keep it coming.
 
#7 ·
I purchased a set of sparco terra wheels that I installed right out of the gate. I'm pretty sure the stock front sway is 26mm. Megan racing makes a 28mm but states it's recommended for racing only :/ also looking at adjustable end links.
 
#9 ·
Let us know how the throttle spacer works out if you decide to use it.

As far reliable n/a 'power' mods, based on my research of n/a Subarus in general, I would say catless headers, HFC midpipe and constant 2.25 diameter exhaust from header-exit flange to axleback exit (feel free to do resonators and mufflers so it doesn't sound terrible or way too loud) combined with a tune is your best bet. EL headers will make more power in the top end, but there is a descent amount of evidence suggesting that UEL style headers, specifically 4-2-1 UELs (versus 4-1 UELs), can help out with lower/mid-range power better than EL headers.


stan_t is right though - best mod for your money would be the lightest quality wheel-tire combo you can find/afford.
 
#10 · (Edited)
Thank you for posting the picture. Looks great ! I will definitely post and let you all know how the TB spacer works. I'm meeting up with a buddy who does custom welding and see about doing a resonaster delete. Figure I'd start with that then save the cash to get UEL headers made.

In regards to the cat delete on the headers how do you get around the O2 sensor(s).

Also thinking of doing 10mm wheelspacers up front and 15mm in the rear. Thoughts there?
 
#12 ·
Damn! That's a fatty swaybar! ...and I'm over disconnecting mine! lol

Looks really good so far. I think you'll be really happy with the resonator delete; I've never missed mine. I'd be hesitant to ditch the cat... a bit of back-pressure is a good thing.
Please, please, please put this thing on a dyno when you're done. I'd really like to see some numbers!
 
#13 ·
I plan dyno it and tune it when I'm done. I'll keep you informed.

The rear sway bar is 20mm, it's a subaru OEM one from the STI. You can get them online thru a subaru dealership or direct, since it came out that they fit on the forester dealers can't keep them in stock. Subaru has them in national backorder. And the best part is that it was 100$.

Adjustable end links are next on my list hopefully that will stiffen it up all around a little more. Still debating the Megan racing 28mm front sway bar. A local shop has it as a set with a 22mm rear for a decent price that I might get.

Megan racing also makes lower control arms that have caught my eye.

I got bit by the bug. And can't stop tinkering on it!

You have me sold on the resonator delete. Looks like I know where I'm going on Monday!
 
#14 ·
Looks great, and I'm looking forward to the future of this.

A tune should solve any issues with the 02 sensors to do catless headers. If you live in an area with emissions testing, I'm not sure catless headers + HFC midpipe will pass. You might have to do an OE cat in the midpipe or HFCs in headers and midpipe to pass, but I would check the BRZs forums for better info on stuff like that (I think OE midpipe would be preferable to dual HFCs to try to maximize scavenging, and closer to engine = more potential effect on scavenging).

Also, hypothetically, catless headers plus catless/straight midpipe should flow better (therefore, likely make more power) than an HFC midpipe. However, I just think fully catless street cars usually sound terrible.
 
#17 ·
CSX racer; I was a young man about 30 years ago ,I was passionate
about cars ,engines and performance like you. I would like to suggest
that you take a look at what you are going to spend to get your
2015 Subie where you want it to be. I bet it's going to be a heck of a lot of $$$$. When you are done experimenting and spending money on your car; its probably going to be worth less than it would if you had
done nothing to it. I am not telling you to stop working on cars ,just be mindful of putting alot of money in your 2015. Here is what I am suggesting, buy an older low mileage,well maintained Subaru,maybe a Turbo and use that as your experimental machine. Used hi/po parts
should be more available for an older car and you dont have to
keep running your new car so damm hard. Also you wont take it on the chin with devaluing your 2015 car. Just think about what I am saying here,talk it over with your friends and or family and see what they have to say. ed
 
#19 · (Edited)
Ed, thank you for the insite. Sometimes it take a 3rd party person to bring you back to the real world. Expecially one with experience. I am always looking at the classifieds and all looking for something that can be my "project". As for resale value, I plan on driving this one until the wheels fall off, but since things are always changing, I have kept all the stock parts so I can put the car back to stock if and when I sell/trade it in. Again thank you for the words of wisdom. They are truly appreciated.

Jeff
 
#22 ·
Well, sure, people go overboard with car expenses. But, that doesn't only apply to cars.

One rule I try to enforce for myself is paying cash for parts, and trying to sell something to fund something else. Keeps the hobby going. Sure, you can just not spend anything at all on a car, but what's the fun in that?

Stan
 
#23 ·
After running the TB spacer for a little while I have not noticed any gain in MPG. But I can tell a difference changing gears. It feels like the is a lot less lag between them. I feel like the wheels get power faster after the gear change ( hope this makes sense). In the end I am very happy with it and would purchase it again.

Next thing I think Im going to do it Jet Performance programmer. It states that it works for the 15' Forester but it has the motor listed as an EJ25 not the FB25. I have an email into them asking if it would still work. Fingers crossed.

Jeff.
 
#25 ·
Well I decided to pull the trigger and get the Grimmspeed Al crank pulley. The weight difference is increadble! Install was straight forward, I did need to use a peice of pipe yo give me more leverage as the bolt was super tight. I did need to remove one of the rad. fans in order to have enough room to get the bolt out.

Once installed I could feel an improvement in throttle response and it feels like it revs a little quicker. All in all I am very happy wit my purchase. Just installed it today so I will post back after I get some miles on it.

I also ordered a Jet Performance computer module which should be in this week. After speaking with the guys at Jet Performance I can't wait for it to come in and set it up! I will post about that when I get it setup.

Let me know what you think. I selling some bicycles and parts now to get some cash for more mods.

I have been researching installing a 3" cat back Invidia exhaust. It's listed to fit the XT, however from what I have seen it will bolt on with the only thing that I would need to do is get exhaust hangers welded on on the drivers side rear for the dual mufflers. (Rear bumper already has the cut out!)

A short throw shifter is also in the plan. As is some 18" wheels and tires. Thinking of going with 8.75 or 9.5" wide wheels woth either 255/50 18s or 255/55 18s. Keep an eye out as I will be posting as I go.
 

Attachments

#27 ·
I know lighter is better, but I love the look of a wide wheel and tire set up. I hate how the wheels sit in so far, so going with the 18's with a different offset would set the wheels out further. I think Id take the added weight for the appearance. That's just me though.
 
#28 ·
What are your guys opinions on wheel spacers? I have been thinking about getting 10 and 15mm spacers to run front and rear respectively. Had been thinking about going 20/25 but think that that might be to much. The spacers come with extended studs. Any one run them before? Any insight would be great!
 
#29 ·
Thicker may actually be better; there are basically two types of wheel spacers:
The simple metal discs, which should come with longer bolts (sounds like what you're talking about)
OR, there are "wheel adapter" style spacers (I'm copying the language of my current state's vehicle modification laws).

The "wheel adapter" styles like are Spidertrax spacers (these are familiar to the offroad crowd). They bolt on similar to wheels, then contain another bolt pattern (or the same) at a different angle / part of the disc with a full "extra" set of bolts.
These are generally thought of as safer. I'm not sure if they exist for Subarus, but I don't see why they wouldn't.

Also, I'd recommend to get hub-centric spacers if possible.

Finally, check your local laws (especially if you have inspections). They may not allow the simpler type of spacers and/or they may require your tires to remain under your fenders, or you have to add mudflaps if they don't, etc. (all kinds of laws out there).
 
#30 ·
Couple quick updates on my Forester.

First off the GrimmSpeed Al crank pulley is AWESOME! By far one of the best upgrades I have done. I can not notice a power increase but I can tell a huge difference in normal every day driving. There is a noticeable smoothness increase after changing gears, acceleration seems smoother (a little quicker) all in all well worth the price.

Second, I went to 5w20 instead of the 0w20 on my last oil change. Two reasons I tried this. First I wanted to see if it would help the oil consumption that seems to plague some of the FB motors and second to try and see it the clicking I was hearing under acceleration from time to time, also something that people with FB motors have noticed and Subaru says is normal. Well I have not seen any difference with the ticking after running 5w20. I've done about 1800 miles since I changed oil and I have not seem a drop in the reading on the stick, fingers crossed. My mechanic at the dealership told me to keep him informed on this because evidently if the consumption is bad enough Subaru will replace the piston rings and if that doesn't work they will replace the block?. And personally I feel 0w20 is to thin.

Lately I have been running 91 or 93 fuel for the past couple fill ups. With the higher rating I can tell a decrease is the ticking sound under certain conditions. It also seems like it runs a little better with the better fuel. I will be using 91 or 93 from now on.

Finally on to the Jet Performance Computer Module I got... first off I was a little unsure if I should pull the trigger on it because even though Jet said it would work for a 2015 2.5i the engine code they listed as the motor being was an EJ motor not the FB. So I called and spoke with their tech support. They stated that there was no reason it would not work. With that easing my mind I pulled the trigger and bought one. Sold my stock steel wheels to pay for it and leave me with some cash in my pocket. It came in and I tore into the box, ready to plug it in and see what it would do. I opened the box and my heart sank. Not once was I told, or was it described as needing to be hard wired into specific sensors. That was the first red flag. The second was when there was no wiring diagram for a 2015 Forester, but hey that's why we have smart phones. After about 45 minuets of contorting myself under the dash I was able to route the wire through the firewall. Ran the cable behind the center console, and then cut a hole in the center change tray for a super clear look. Next I went to figure out what sensors I needed to wire into. Third red flag came when I figured out that I could not just wire into the sensors, but I needed to cut the wires and then attach them. Well I was over an hour into it and I still felt that Jet knew what they were doing. Found the correct wires for the MAP sensor and TPS sensor. Connected the power and ground wires. Cut and connected the sensor wires and got ready to try it out. Got in and started her up. Well guess what the check engine light came one. Okay. No big deal probably just needs to run thru the set up process. So I turn on the Model and I'm greeted with a glorified instrument panel. No way for me to chose settings, fuel used, or anything. I reread everything. I'm 3 hours in at this point, on a Saturday, after working the midnight shift. Check and recheck everything and its all set up how it should. Still check engine light is on. So after a ton of obscenities I undo everything and throw the Module back in the box. Check engine light stays on. ***. I drive it back from my dad's, where I do most of my work since he has a larger garage and tool set, and it drives like **** and fuel mileage is horrible. End up having to take it to the dealer because the code will not reset. Ends up having to solder the wires back together and now she runs great again. Now I am stuck with a $250 paper weight. I thought I crossed all my Ts and dotted all my Is. Evidently Jet does a ton of great stuff, just not with this one. I guess its a great product for some people. I just wish its functions were described better.

Any way my mechanic said he would have his friend who works at a tune shop get a flash tune set up for me. He said that this guy's wife has a 2.5i that he tuned and evidently its pretty impressive. So hopefully I will get that done soon.

That's about all I have right now. Hoping to get the short shifter or a set or 17x9 XXR wheels for Christmas. Any way thank you for reading. Sorry for the long post.

As always please let me know what you think and what things you have done. Best wishes.

Jeff
 
You have insufficient privileges to reply here.
Top