Ceramic coat exhaust and performance gain questions
 

Long post because it has to be to explain everything.
I am going to stay NA and am only attempting to up the horsepower a little and reduce SOME of the torque dip as possible with these mods (secondary reason for exhaust changes, getting better sound). I will NOT be changing the header even if it would make the most difference. Run 93 octane pump gas with no plans for E85 since it is so hard to get in my locality (30 miles is just too far for DD) No interest in FI /turbo/super charger mod.

Waiting on delivery this week of: Perrin Exhaust 2.5 Overpipe + 2.5 catback resonated exhaust (PSP-EXT-360BR). Have a Berk Catted 2.5 front pipe which will complete my header back system.


Thinking about thermal ceramic coating because I want to keep the temperature down under the car, keep ‘new’ appearance… not expecting much performance boost from coating since NA.


Question 1 - Contradictory information saying Yes or No all over the Internet that only coating the outside will damage SS exhaust pipe due to excessive metal overheating under the coating. Do any members/anyone at FT86club have actual experience ( anecdotes of my friend’s friend’s uncles friend, I have read plenty of. Looking for member real world long term experience that is not yet covered in any exhaust thread of which I have read all of them, mostly from years ago, here and on other FT85/FRS/BRZ sites) Note that the catted front pipe can not be inside coated anyway plus there is more contradictory info about OK or not to coat outside of cat because of claims of ‘overheating’. Bogus?


Question 2 - Best coating and what company gave best customer service?: Lots of discussion on whether to coat headers but not much on other parts of exhaust system. Very few posts on what coating was actually used or any feedback on long term satisfaction and durability. These questions should be of interest to the FI guys so lack of information is puzzling.


Question 3 - Have looked at: Performance Coating, Cerokote, Swaintech, HPC Extreame… any others to consider (Note: JetHot has a very bad rep when I asked here locally)


Question 4 – How much will ECU adjust to these intake and exhaust mods? I know a tune will bring out ‘everything’ but I am asking for anyone with any idea if the ECU ‘limits’ adjusting to a set level much below the possible with these bolt-ons… or will OFT tune be mandatory to get ANY gain at all? Just how much will the ECU ‘learn’?



Honestly, with what I have done, mainly I wanted to lessen the torque dip. I would just go with mods I have listed without tune (understand I am not expecting much HP increase without header). I obviously have a warranty on a brand new car and feel I can get away with bolt on parts legally… but if I do a dyno n tune or an OFT it has to be undetectable / reversible when I will be using the 7 year unlimited mileage bumper to bumper dealership full service + repair warranty policy. Service every 6K miles at dealership.
Read all the threads n posts by Steve99 and others but still have questions about…


What I have done/installed so far since bought my Bluescoot in September 2016 {not counting above exhaust to be installed soon}:
1. 1. Oil Cooler Kit by RacerX Fabrication: { BUT instead of their hoses instead had two custom -10 [ Ouch! ordered/approved without asking cost, because RACECAR! Custom hose cost $308.08] Chemfluor® PTFE fluoropolymer smooth inner tube and EPDM cover, reinforced with a 304 stainless steel tube tensile strength braid stainless hoses n stainless fittings} and Setrab Proline 613 cooler.
2. 2. Horns (WTH, just had to while had front end open installing oil cooler): PIAA Sport #85110, 115db, 400HZ + 500HZ …Great sound compared to OEM toy horns.

1. 1. MTEC Clutch pedal replacement spring
2. 2. Change to small bore transmission/Clutch slave cylinder as per http://www.ft86club.com/forums/showthread.php?t=77390 , THANKS Ultramaroon!!
3. 3. Adjust clutch pedal height with linkage clevis to ‘even with brake pedal’ to adjust ‘clutch grab’

1. 1. Drain n change transmission and rear differential fluid to Motul Gear 300 75W90 (with new fill n drain plug washers)
2. 2. TRD Quickshift kit, PTR54-18130 (used RED Loctite and no bolt loosening prob in 6 months) http://www.ft86club.com/forums/showt...sion+whiteline
3. 3. Whiteline Positive Shift kit bushing KDT926 transmission mount insert
4. 4. MTEC Transmission shifter/centering spring(s)

1. 1. Crawford Performance BPB ‘Billet power blocks’
2. 2. Crawford EcoBlock


Results: What the car SHOULD HAVE BEEN from the factory. Clutch and shift feel are just ‘right’!

I don't know anyone who's coated their exhaust so I don't really think that's necessary. I've seen wraps and coating on headers though but I've also seen just as many guys running headers without wrap or coating.

Again, I don't think you'd need to coat/wrap anything but headers.


See above... In general though I recommend going local when possible for the best customer service. It's a lot harder to be a jerk when you're talking with someone face to face.


Since you aren't doing headers I wouldn't worry about shit tune wise. I mean you could get an OFT and load a tune but performance wise the header-back bolt-ons you're looking at won't help. The tune alone would do more.
Honestly man, if you're looking to get rid of the "torque dip" (which isn't that bad) then you really just need headers and a tune. The other bolt-ons might help your ear and butt dyno but won't show any real gains. Most bang for buck, you'll still get good sounds and the car will drive better.

If you want to maintain your warranty, the tune is tricky. You can more or less revert an OFT without Subaru/dealer finding out. ECUtek leaves the license on the ECU.

Welcome to the forum, there, BuffDriver ....... :clap:

DANG! ....... that was a long post ....... :eyebulge:

I think that coating any of those exhaust parts you were speaking of, would be a waste of time and money.


humfrz

1) Long term, coating does more good than harm, because it exposes the engine bay and electronics to less heat. That simple.

Coating the outside of a catted header is the same. If anything, it helps retain heat inside the header and can reduce cold start emissions by warming up the cat faster.

2) No idea

3) No idea

4) Stock ECU will make your gains very little on paper. Tuned ECU can give a lot more. I guess you can look at it this way: people don't tune ECU and keep I/H/E stock.

I thought that the OP was talking about coating the header back exhaust pieces only ..... not the header itself ..... ??


humfrz

Only put 02spacer in rear o2 sensor

if you get the cel for cqt efficiency P0420 it will light cel light and disable cruise control, you wont go into limp mode unless you havecother issues.

when you get your oft remove the spacer


read the links below on basic mods and oft tips should give you most answers

coating header may help with corrosin issues but most decient headers are made of quality stainless anyway, wraping header cmay lead to increased corosion as it traps road grime

keeping underhood temps lower is main benifit ,any performance gain would be minimal.

you ca also keep underhood temps lower by runningvthe radiator fan at lower sppeds\temps its just and adjustment inbtune and could cost you nothing depending on tuner.

Even the factory front pipe and overpipe has heat shields, so the same principle applies.

A tune that runs lean, especially a force induction tune that runs lean, could produce enough heat to cause damage out the back, but I doubt you'll do anything stupid like that.

But basically, you're worrying about nothing.

Tuning with OFT or tactrix , is reversable as a 100% stock rom can be returned to car. so the CVN or checksum valuecnumber is same as stock.

no flash cointers found as yet as not aware of anyone who hasxbeen nailed by flash counter

They will probaly give you a hard time with oil cooler with engine warantee.

if you get a tune you will want to remove the craford eco block maf adjusting device for sure

and likely the power blocks as well if your not looking to get power lower in the rpm range at the expense of top end. both these devices are rearly designed for untuned cars,

Oh, OK ....... thanks for the lesson ...... :thumbsup:


humfrz

Thanks for the interesting and informative responses
To clear up some points, I am keeping the stock headers and will not be coating or wrapping them right now because I can't take my car down for so long. I am sure no expert but based on some performance sites I studied for NA engines, it may help to have the smaller stock header pipe for the scavenging effect (and that is also part of the too little backpressure lowers torque bit, might be that guys installing header but keeping stock exhaust pipe are still keeping backpressure but changing flow pulses in exhaust gas for an improvement?) which then opens up to a larger diameter if the gas can be kept hot in the pipe... which the ceramic coat does. I want the engine to breath better and keeping the exhaust gas as hot as possible in the larger pipe is supposed to help with flow.

I have not driven anyone else's 2016 but mine has a terrible 'flat spot' where you literally feel the car sort of sag back as you accelerate through 3500. Mainly that is the whole purpose of the mods. Of course any added horsepower would not be refused but even 10 HP would be OK, I am not looking for 240/350/400 or more because if I wanted that I would get a turbo.

The second reason to coat the full exhaust system after the header is just a pleasing byproduct and that is purely cosmetic, keeping the pipe 'purdy' in like new condition as long as possible. Yah, its stainless but it still discolors.

Thanks for the tips on the OFT, I have read all the 'colored links' provided by Steve99 and am ordering one. I mentioned my warranty earlier because with it the dealership and I will have a close relationship for a long time. But I am going for the tune anyway. I have had good luck with Subaru {bought a BRAT in 1979 and drove it for 220K miles, sold it still running great} and Toyota {five Celicas} down thru the years and I believe this car will stand up without ever needing the warranty. And if it does, well, I will just take the hit. And that lead to finding and calling a local tune shop that specializes in Subaru and will use my OFT which was pleasantly surprising (is it OK to give their name? EngineLogics). And for sure will adjust the fan, again as per Steve99. That's why I have been so glad to find FT86club, I honestly believe I have spent 58 or 60 hours reading thread after thread in the last 5 months! So informative, motivating and sometimes amusing too.

Followup Note: As per the coating, I am going with another local shop I found today through recommendations from the two wheel side of my life ( I also ride {too fast} on a 2006 Honda 919/CB900F ). Everything is coming together all at once.