FA20 bolt-on horsepower gain potential
 

At a local car BRZ meet in Sydney, i heard that the FA20 is more responsive to bolt ons that a K20 Honda engine. I purchased a AFE takeda intake from a BRZ owner i met at the meet. I plan to put the following mods after my friend carbon fibre wraps my car:

- Perrin Headerback exhaust
- Stage 2 FA20club tune
- Borla UEL headers

If you put the same mods on a K20, will it gain more or less power than the mods put on the FA20? And also how much power will be gained from the listed mods?

K20 vs FA20?

EDIT: Surely if the FA20 had 1k more rpm that is part of its powerband, along with a 2nd cam profile that had some sort of VVTL-i that was in the Celica. It would make much more power, perhaps even more so than the s2000.

Here in Australia, the Integra Type R are called Integra Type S. They have 164kw (220hp) stock, and can rev to 8600 rpm. I had a Jap Spec Celica that had 149kw stock (200hp) that could rev to 8400 rpm. My roommate back then in uni had a Integra Type S and he didnt have much money for mods, so he just tuned his integra. I put AEM cold air, PPE headers, Magnaflow custom catback exhaust with no cat and 2.5 inch piping, as well as tuned it with an Apexi Power FC and increased rev limiter to 9200. He still beats me every single time at the drags :(

http://www.ft86club.com/forums/showthread.php?t=34462

http://www.ft86club.com/forums/showthread.php?t=17906

I had a K24, I gained roughly 30-40 whp over stock by having, CAI, 3 piece lightweight Pulley, Hondata reflash, TB spacer, lightweight wheels, IMG gasket, Injector gasket. No exhaust mod whatsoever, I think there were a few other mods I forgot to mention.

My K24 dyno(SAE CF)
http://imageshack.us/a/img196/9932/m...runsnocorr.jpg

The K20 have a lot of potential(as we all know) and you can easily gain 100whp NA over stock by bolton mods, Manifolds and cam gearing + e85.

The FA20 is still fairly new, I have yet to hear anyone building or R&D'ing an Intake Manifold or cam gears for it. If you want to make the comparisons, FOR NOW we all know the K20 responds better to bolton mods than the FA20, but at this stage it is still too early to tell because the K20 has already been out for over a decade..

Wow without any exhaust mods, that is impressive! :respekt:

Looks like it would be a fun themepark ride. Why so bumpy? Wish my TSX K24 felt that fast haha.

I think the K20 has higher potenial. From what I have seen, with bolts on and flash the K20 easily get over 210whp on pump gas.

So far, the FA20 with bolt ons, the highest number that I am seeing is about 190whp on pump gas.

5 speed automatic transmission lol. If it was an MT, the numbers wouldve been higher.

sounds like dude was trying to sell you bro.....not even close to a k20 mod for mod. 200whp was easy in a k20. Could be though that this is just a new engine and not all the research and development is out, the k20 has been out since like 2001 i believe depending on the variation.

That's about what I put down with an afe and srt. Never tried with a header. I put down 204whp on e85 with the same mods. LOL

I've put on the AEM intake, FA20Club header, and Unichip EMS. This setup has really transformed the car. I'll be getting it dynoed next Saturday so I'll know for sure. I'd estimate about 25-30 whp.

The dude was maybe trying to sell me the AFE takeda intake. But i got a very good deal on it 250 for brand new, still sealed in the box (Here in aus, we have to pay 300 for the intake plus shipping which is about 40). After installation, the low end torque is much more, similar to my friend's 2011 wrx sti BUT the torque dip is way more noticeable :(

Keep me posted please. I really want to know! :)

Please keep us updated. I am traveling down this route as well and wondering if headers are worth it.

Adding the headers and tune seem to be doing a great deal to take care of that dip.

I have a DC5 integra Type R with the original K20a engine from 2001 (JDM) and it responds exceptionally well to bolt on mods.

The Type R came with ~225hp at the crank (~195 whp) from the factory the JDM model was already tuned when it was stock thanks to easier breathing headers, aggressive cam profiles and port polishing.

With Intake, Throttle, Catback and Hondata remap it is now making 210 whp and its 12 years old with 85k kms on it.

The FA20 has lots of potential, but it will be years until it gets to the level of the K series Honda's.

As much as I love my BRZ, I still like to get back in the Honda for a real thrashing every now and then - nothing quite like a 9,000 RPM screaming beast.

I don't think the Borla UEL headers will bolt up to the K20...

:D

Seriously though, apples and oranges man. The vast majority of the power available seems to be in the headers, then the intake - the header and intake you have chosen are not the ones most backed up with results.

Go P&L header (or wait on nameless), and TRD intake (SORRY, but best dyno results so far).

I must have been the only person to have a crappy K20. I had an intake and exhaust on my 08 Si, and it was still pretty slow under vtec. I enjoy the powerband of the FA20 much more. It's definitely more suited for every day use.

But on the topic, the K20 will always get more from mods because it just breathes better with the 2nd cam profile.

Wait for cams and revving to ~9k to see how the FA20's do, but bolt on vs bolt on, the K20 definitely responds better.

There was (might still be around) a company that sold swap kits to put K20's into Elises that would regularly get 250whp on pump gas from an intake, header, exhaust and flash tune.

Note that the K24 above already has a 20% displacement advantage over the fa20 and less drive train loss (fwd has less loss than rwd which is less than awd). Taking away the displacement and drive train advantage that k24 would be making 175 - 180... right where the fa20 is with a few bolt ons. Not bashing the K series in the least just pointing out that liter to liter and drive train to drive train the numbers are about the same in this case.

Also, what did / do bolt on k20's make at 7,000 rpm? Revs are a huge advantage if the heads and cams are designed for it. and engine that makes 175 whp at 7,000 rpm is making about 130ftlb at 7,000 rpm. An engine that makes 130 ftlb at 8,000 rpm would be making 199whp at 8,000 rpm.

Equal length long tube headers seem to be the first part that allows for significant power gains with tuning. Given another year... cams that peak at 8,000 rpm along with the supporting valve train work and the fa20 could easily be at 230 - 240 whp on pump gas.

Thats not to say it would be cost effective since you have to drop the motor to do cams or head work... i think that is going to be the real weakness with the fa20 :(

I was thinking exactly what your writing about!:thumbup:

It would only make sense if the k20 was restricted to 7450rpm and then the cams were changed to not have a high rev powerband. In that sense, the k20 would have significantly less power than the fa20, and the bolt on potential would be not as great.

Still i love K20!

Yeah, when i had my Celica and was at the drag races in Eastern Creek. There was a guy who is on Lotustalk and he changed the 2zz-ge out of his Lotus Elise, sold the 2zz-ge, put a K20 in it, turboed it with forged internals, put a roll cage, and had full drag slicks on, ran a 8.8 sec 1/4 mile. Beat a Evo tommy makinen with supposedly 442awkw (592awhp). Utterly insane.

K20's are no joke. I was tempted to do a K20 swap into my EG hatch a few years back, but I ended up going with a non-vtec LS turbo. Pulled a LS motor and trans out of a junkyard integra for 200 bucks. :party0030:

The K20s are great if you're looking for a whp figure. But in day to day driving, they were just like any other economy 4 cylinder. Still have to downshift to pass or get up a hill.

I do like the FA20 for daily grunt in traffic and generally like the engine for different reasons from the K, but when I was NA on my K20 it was a screamer with IPS cams and upgraded valve train. When the rpm climbs up there that's where I start to feel somewhat underwhelmed with the FA20. I don't think it will ever have that kind of NA potential. As much as I've tried to shy away from it, I think a small turbo is right for this car to exploit what it's good at.

Absolutely. :thumbsup: That's what I was trying to say lol

Motiv is working on an intake manifold.

Maybe Grimmspeed will work on one too...

Add Nameless to the list of possible manifold companies....

Word. I've gone back on forth on this car kinda wishing I could keep it NA for the throttle response and try to improve that. It's a wonderful car with what they did with compression and direct injection to push what they could from the motor. It's obviously a great combination for twisty roads and powering out of turns.

I like the results you got with e85. If I could get 200whp on 93 I'd probably keep her NA. It's just too inconvenient for me to fill all the time with e85 (without a flex fuel solution). Since you are 200whp on that fuel, how do you like it? Is 200 enough go or do you find yourself desiring more?

Yea, I want to try full bolt ons and see what it makes. Been a bit gun shy on a header because people aren't really seeing much when it's combined with I/E from what I've seen.

I think this motor needs cams, honestly. Right now it flows nice from 2500 to 6500, then starts gasping. If we could get cams that bump that band up to 3500-7500, you would see very nice gains without sacrificing too much of that low end grunt.

I agree, and coming from a car that's freakishly loud I'd like to keep this one on the civilized side. All I've really done is the tune which I knew would make the largest difference. Since these headers seem to fix the "torque dip", I've been thinking of staying stock on the exhaust and doing header/overpipe only... and hoping stock exhaust keeps it from getting obnoxious.

An AVO turbo kit would help with the obnoxiousness too LOL. I'm leaning towards that. The turbo seems to have great response for the motor. Don't need to run dangerous amounts of pressure to get power, either.

I believe k20 is much better mod friendly and gives more power.
I had 05 RSX-S with BuddyClub Race Header (cat-deleted), 2.5 inch Comptech Exhuast, Injen Cold Air Intake, K-Pro street tuned.
I didn't dynoed but i put a bus lengthed on my friend's AP2 with CAI, Exhaust.

I've been thinking the same thing. Of all the FI solutions, that would be the one and the quieting effect of the turbo is attractive while adding the power. It's definitely a slick setup and I've been watching @Sportsguy83 with a bit of envy. I'm enjoying the reliability of NA too, though. It's nice to take a 5+ hour trip feeling confident nothing... unexpected is very likely.

But yeah... still terribly torn which is why my money is still in my wallet haha.

Yea, a lot of people would jump on and hark the Vortech kit, but IMO, it's a tad overpriced and underwhelming to drive. Can also be a pain to install/take off. But, at least they are finally starting to hit the originally advertised numbers with the new kit. I'm a little concerned that it takes 10+ psi to get there, though. I"d love to see a head to head comparison between the two.

I kinda look at it like they aren't really very comparable. A turbo's always got the upper hand at making power. I think of supercharging as mainly adding moderate power past what can be achieved NA, while trying not to change anything else about the car's character. I think the right PD supercharger might do a better job at that mission than a centri (I've had two roots blowers and I did like them), but I'm no longer expecting much from the twin screw we've been waiting to see for so looooong now.

To be honest, I really don't know what a really small turbo feels like. I've got a GT3076R on my other car and while it spools very quickly, you know it's there and it is a surge of power. Perhaps the AVO's is small enough that it performs much like an SC.

Not knocking what you're saying, but it's not just revs. People have been swapping K20's into S2000's because they can make way more power with bolt ons and cams than they can with an F20C, and those rev to 9k.

The K20's are a VERY good engine, and respond very well to pretty simple mods. Not saying there isn't potential with the FA20's at all, but comparing them to K20's is a really high benchmark.

you have to be careful with small turbo's in that the smaller you go the more you limit the top end potential... Personally i want to see what the twinscrew does but, like you said, i'm not expecting much after all the delays.

After years of driving modified factory turbo cars I'm also not in a rush to get away from NA reliability and the not having to worry about it factor. I do think it is going to be cost prohibitive to make the kind of NA power that will keep me happy in the long term. Cams, head work, etc all require pulling the engine and they will be required to make serious NA power, or so it seems at this point in time.

If i do go FI though i am leaning towards supercharger because i"m tired of turbo power delivery characteristics and the other fiddly bits like reliable, repeatable, boost control etc.

I think another year of boosting under the fa20's belt and we should have a lot more data on reliability, or any lack of.

You should do a google search for "vortech leaking" ;). The reliability is a non factor between the two different FI platforms.

But they make power because of the heads right? Or more specifically, the k20's responds to bolt ons so well because the factory head flows so well. That's why i was saying revs are a huge advantage IF the heads and cams are designed for it.

Sadly head work on the FA20's is gonna be expensive :bonk:

So sad...
 

Is there any engine in the NA 4 cylinder benchmark that is better than the k20, or even equal, or even close to as good?

The reminiscent days of the golden age of Honda...