High Revv NA Setup?
 

ok so i know that 90% of the power junkies out there will be all about turbo and supercharging our beautiful cars. but has anyone actually considered the other option? we have a square engine which is an amazing thing for high revving setups!

is anyone out there at all interested in going for a high revving NA setup? little valvetrain work, maybe just some valve springs, tune, exhaust and intake? see where that puts us, and hell maybe it'll be able to make power up to 9000rpms! that'd be an amazing thing! frankly if i was able to squeeze 260hp out of a 2.0L flat 4 that gets 34mpg then i'd say it's already a 1 up on the RX8 :P

call me optimistic but i think that keeping at least one of our cars in the fully done out NA setup would really be something to see! pretty sure that if need be porting and polishing of these engines would be a great way to get more out of the NA setup.

i know plenty of people out there have already gotten great numbers out of their turbo kits, which is awesome! i'd just like to see what the NA setup can do too :)

I want to keep this car to stay NA as well. I love how the power feels very direct and linear. I think that this route makes for a better balanced tune. Mechanical tuning FTW! =D

that's what i'm talkin bout! granted a centrifugal supercharger will just amplify the stock power curve, but i still say NA is going to be the way to go for the best possible response, especially for track days, quick autox, and back road bombing.

my personal belief after owning turbo and NA cars is that while something like a WRX will have a lot of usable power, placing a WRX against an all done up RX8 or Integra Type-R, it's hard to match the response of an NA engine and immediate inputs of a NA setup. easy predictable power :)

how do you plan on getting 9k rpm AND 34 mpg?

Thats what the factory gave you - high rev NA, you could extend it further but extra rpms are very destructive to an engine not built for it. Turn it into an F1 style engine for mega rpm tho would be SWEET - $40k for the engine built out of exclusivarium metals with electrohydraulic valve actuators (no cams).

If you're going the NA route it would likely be best if you can find aftermarket company that offers NA performance part for example, intake, header, and camshafts, rather than buying individual part and hoping they make a difference. Especially in this engine with relatively high volumetric efficiency and fairly optimized components already included, it might be hard to see any actual gains otherwise.

people have tested this engine up to 9k rpms with no problems .. i'd have some trouble digging around for the thread that talked about this though .. :/
don't remember which group did it

Yeah I saw this somewhere also, I'm sure it could rev up to 9K but I think it's capped at 7400 for that sake of preserving engine life.

Forces increase exponentially with speed. The higher you want to go, the more you spend replacing the moving components. What you want to build is essentially a race engine, and the lifespan of race engines is measured in hours, rather than miles. Forced induction is a way of increasing output from combustion with linear inreases in stress. Not telling you which way to go, but there are FI routes that achieve what you want more economically and reliably, eg twins crew superchargers.

Why don't you stop by Honda-Tech and tell them that everyone running a 9k RPM engine is a "race" engine? There are plenty of B series, D series, F Series, and H series engines running this high and doing it reliably every day.

To the OP:
I agree that this could be a great rev happy engine with cams, valve springs & retainers, and maybe a port job depending on how good the stock heads flow.

sorry dude... but I kind of agree with Mitch. Yes there are plenty of Honda motors hitting 9K and beyond, but those motors have all been on the market for a minimum of 5 years and in some cases as many as 20. There have been plenty of motors popped and lessons learned a long the way about what can and can't be done... just because it can be done in a Honda motor doesn't mean the boxer 4 will like the same things.

To the OP, I think it is an interesting idea... I'm sure there will be people that explore the option... it is really going to depend on how well the aftermarket jumps on board with this platform though, because an NA build requires some very dedicated companies making some more focused parts that the high HP chasing crowd might not be willing to pay for if they are just going for bang 4 buck. You're going to need valve-train components, cams, head work, tuning (ecutek seems to be at the for-front right now)

I'm interested in going this route eventually. I'm probably going to look at increasing displacement as well as revving higher to make power.

Well, at 9k you are right around 5000fpm piston speeds. That is not that bad for a 86mm piston. Not a lot of weight, and factory cars have been doing it for years without any failures at all. Think S2000.

9k rpm is not difficult, nor is it unreliable. Putting springs/retainers, cams, headwork, and decent bolt-ons with a tune on E85 and people will be hitting 250+whp.

You can get 34mpg with a high rev setup without issues as well. The cams are going to impact the mileage depending on the profile chosen and how the advance/retard on the cam timing is handled by the ECU. But it won't be that hard. Revving high with small engines is a great way to improve output. Responsive high rev engines are really fun, and stays true to the spirit of the GT86.

I don't think you can go wrong with whichever route you choose, as long as you actually get the car lol.

Would it be fair to assume getting any serious power gains reliably long term out of the 86 N/A is going to set u back a similar $$$ to that of a decent turbo kit anyway?

NA is expensive per hp gained. Much more than going FI. 300whp could be had on FI for relatively cheap, and upgrades from there give even more bang for the buck once the hard parts are purchased.

I can see cams costing a good chunk. Probably $800-$1000 for perhaps 20-30whp gains, mostly on the top end. Even after that and full bolt-ons, you'd be hard pressed to be anywhere near 300whp. It's a hard mark to hit with a 2.0.

Maybe per HP gained but id rather have a 260 whp NA monster than a 340whp force induction monster. I like linear power delivery and throttle response which is great in a NA!


I agree, Cams, Valve Springs & Retainers, port job, headers, exhaust, pulley, intake, larger Throttle body should be giving us around 250-260 WHP with a good tune and 9k rpms easy.



Anybody wonder if ITB'S are possible in a flat 4? I wonder how it would sound :eyebulge::thumbup:

ITB's are possible in a flat 4 (racing team I am on had ITB's on a flat 4 for awhile)
However, I don't know specifically to the FA20. Im sure you can setup something customish. Would open up your injector possibilities.

That monster would be working a lot harder than FI though pcasso i would think... Dont get me wrong its just my guess....

When i was considering squeezing my LS2 6 litre ute for 500hp i looked into cams, higher comp, valve springs blah blah blah and it worked out much more easier ON PAPER to just run a big single snail especially $$$ wise.... Plus i already had spent a lot on exhaust, headers, OTR intake etc which would have all needed to be replaced... http://t3.gstatic.com/images?q=tbn:A...hidC5LkgmpNOLA

Gladly this was around the time rumours were getting around about the FT-86 so i backed out...

I think a near 300hp N/A 86 would be epic no doubt but at what cost we will soon know.

Thumbs up to everyone having a go :thumbsup::thumbsup::thumbsup:

I agree! Money does add up when compared to a Turbo bolt on kit. Everyone has their own taste and I already did the high compression N/A thing. It is a beauty, but its hard on the engine and pricey! As soon as I saw AVO kit, I started leaning towards turbo. Thinking back at memories of my Civic Frankenstein, I'm definitely going Turbo for this car.

With that said, I am looking forward to the N/A monster builds this forum provides!

I'm sticking NA as well no question. After owning high power, low power (no power sometimes lol) NA and FI engines I've decided to keep my cars NA from now on.

Of course this is not an NA vs FI thread so I'll just add I'd like 240ish crank hp and a redline around 8500 and I would be a happy camper.

I think I'm going to be sticking with NA power and weight reduction with this car.
If I want turbo power I would rather pick up a used 2005-2007 WRX, STi or 2004-2005 SRT-4 Neon.

I am also wanting to keep the engine N/A!

While definitely not the end-all factor, Rod/Stroke will also play into high-revving plans. Consider what seems to be a short rod length @ 130-131mm*. This will put your R/S ratio at 1.51-1.52. Not exactly the best starting point for a 9k engine.

A higher R/S ratio will lessen the side-load on your cylinder walls which is nice when wanting to rev to the moon :)

A few mentions of Honda engines. Hondas are already at an advantage for increased revs due to this factor. K20A engines were in the neighborhood of 1.62, iirc. B16A(:wub:) screamers were at 1.74.

The mentioned S2000 F20C engines were at 1.82, but note that when Honda introduced the F22C for the S2000, they increased the stroke which lessened the R/S ratio to 1.65. No coincidence that they also decreased the redline.

One of many factors to consider when revving high. Looking forward to fellow all-motor builds!

*If someone knows the actual rod length measurement of the FA20 please educate me. I've been looking all over the damn place and can't seem to locate it.
:happy0180:

Will have to wait much longer for suitable parts, as well.

So far we haven't heard any news about cams afaik.

I'd love to go for a bit of NA tuning, not because I can get mega power for the least outlay, but because of the feel...

In the end, that is what this car comes down to IMHO - it doesn't matter how much power / grip / stickers you've got, it only matters how much you enjoy the car...

To the people who say "it would be easier to get xyz power with a turbo and less expensive" good for you, but maybe I WANT to go down the NA tuning route... If it was easy, everyone would be doing it and it would be boring, much like hearing people bang on about how underpowered the car is and how it really needs a turbo - find some narrower roads and it'll feel like you're doing 10 times the speed and then the car won't seem underpowered............

There is something wonderful and challenging about pushing a high performance N/A to its limits. Where as FI cars I found were just completely enjoyable and pretty easy to maintain boost during HPDE when you get use to your own setup. I could never get use to retaining powerband in a N/A during HPDE but that's what made it more fun.

Ill be shooting for 250whp for my n/a build. which is going to be horribly challenging to gain that extra 100whp while retaining good reliable performance. The engine needs to comfortably make 250whp rather than straining at 250whp, so moving the powerband up on the RPM scale might be necessary to achieve that.

I want to guess the limit of this particular engine in N/A form fully built for HPDE is 300whp-350whp. While peakers might achieve 350-400.

260 whp is a pretty awesome goal, I myself am shooting for 200WHP for now with a NA build and will probably keep it at that level for quite some time. I have never modified a cars suspension or breaking systems, so once I am around 200whp, that would be my next step (also will be the only time I consider up sizing my rims diameter and width, so suspension upgrades will be essential to keeping a nice and balanced setup)

With my current list of parts, I think a header and a personalized tune on a dyno would be all I need for my car to hit 200WHP. Or just switching to E85 and getting a personalized tune with my Airaid intake, SRT header back exhaust and my Perrin Pulley..that could do it too.

I am excited! N/A will be this cars forte I think. Boost is great, but I hope that in10-15 years this car is still being featured in car publications with unique NA builds just like honda's and nissans of yore are today.

I would prefer a good NA tune to a FI setup myself.

I think what they're doing with the STI BRZ is perfect. 250hp, 8500rpm, and lighter weight. In a few years if that car doesn't materialize I'll try to reach those numbers with my BRZ. I think the key to making this car fast is going to be weight reduction and not big power.

Where do you think you can achieve weight reduction in your current car? panel replacement would be expensive, and they are already quite light (unless the rear fenders were to be cut off and replaced with carbon?) the hood is so feather light...

Back seat delete, battery replacement, lose the spare and maybe cut out some sound deadening and you are probably at a 50lbs or more loss BUT the car would be noticeably louder** and could lose its DD status - however that would be the cheapest options. Changing rims could net a reduction of a few pounds per corner also but is an expensive en devour. I ask this notto shoot you down, but because I too am curious.


**disclaimer: I make this assumption based off previous claims that removing the spare tire and rear seats allows for the exhaust noise to permeate through the cabin much more easily. People were seeing internal DB ratings increase as much a 5-10DB with those deletes AND aftermarket exhausts (DB ratings were limited to 1-3 with just the exhausts)

I cant wait to see if ITBs will be possible, but ill most likely do that after cams/head work.

I wonder how far this car can go on a DDable 93 or e85 setup once its fully setup for N/A

Seems like some tuners are able to flirt with the 180-190whp mark with just a full cat-less exhaust and minor intake mods, no tuning. I'm willing to bet that 200whp can be achieved with a full exhaust with hi-flow cats, full intake and ECU tune. Getting to 240-260whp would be a bit of a challenge, no doubt. I'm sure 10-15hp can be had from cams, and more peak power from raising the rev limiter as the engine seems to want to keep making power up top. There's more than one way to skin a cat, and I think it will be interesting to see what develops in the coming months! Maybe if 240whp can be had N/A on pump gas or with water/meth injection, it might be enough to keep me away from supercharging!

According to my estimated numbers I will be between 180 (lowest hp gains) to 192 (highest hp) whp in my car with full exhaust, tune, pulley, intake and a tune. who knows if the pulley does anything really but I would still fall within those numbers. I am excited to find a dyno somewhere and figure it all out.

Problem is, if my exhaust makes the 11 whp max, the intake makes its 7 whp max and the tune makes the 14 whp max (all dyno shown maxes on the same make of dyno) it does not mean all 3 combined will net me 32 whp - so I will have to do all the work and find out!! I guess this is a thread I could come back to and post my results once everything is ready!

There are 2 weight reduction threads already on here.
http://www.ft86club.com/forums/showthread.php?t=7881

Conservatively...
Battery: 30 -> 4 lbs
Spare + tools: 30 -> 0 lbs
Rear Seats: 20 -> 0 lbs
Track Pipe: 36 -> 5 lbs

Potential of 106 lbs. It is not bad.

Then I would go for the two front seats as they are HEAVY. I would install lighter bucket seats if I was just tracking the car. I don't know about DD'ing it. I think I would want the safety features of stockers.

Oh dear, that's going to be hard. Do cheat with E85 to get you that extra 10% :P Moving the power peak from 7k to 8k with longer duration cams and a different intake manifold (full exhaust and the rest of the jazz too) can net perhaps 8/7*165?lb-ft/150lb-ft * 200hp=251.4hp, at the crank, with very little room to play with after 8k, and a rather peaky powerband before that. From the exhaust numbers and stuff we're seeing, I think 170lb-ft shouldn't be too hard to hit. But now you are looking to find that last 10-15% "drivetrain loss", that's going to be tough on pump gas! (let's admit it, 9000rpm with a 1.5 rod stroke ratio isn't so good for the cylinder bore or bearings) E85 should get you there though, if you can direct inject all of it. When done right the charge cooling effect on pre-combustion pressures alone should be worth 3% more power, or something like that (I did some calculation a long time ago).

@MattR, I think Crower or someone did post a picture of the EJ rods next to the FA rods, and after I asked what the rod lengths were they did post it. I just remember it was 130+/-1 mm.


Actually, this should be much easier than you think, given that we're willing to accept slight compromises in cam design. I believe one of the biggest reasons for the poor low end performance of big cams is that the big amount of overlap introduces large amounts of exhaust gas into the charge, completely ruining combustion efficiency. They say direct injection helps to increase the tolerance for internal EGR, but when you're idling and the vacuum is high, any overlap is going to mean a lot of exhaust sucked back in.

Larger cams however will lose volumetric efficiency at low rpm cruising conditions, which will decrease pumping losses and allow a cooler charge which further increases efficiency.

If you see some Toyota diagrams for VVT operation, you'll notice the range of cam movement allows the stock cam to be retarded to the point where it opens several degrees after TDC. So a performance cam that doesn't go too crazy on overlap can likely maintain near stock combustion quality characteristics at low loads. I mean this for both intake and exhaust. We lose a little bit of scavenging like this, but maintain driveability and increase fuel economy.

I know!!!!
what are your thoughts on Big bore Kits with non-stroke altering characteristics. We might get plenty of headroom if we bore it to a 2.1-2.2 or could just stroke the crank. And just keeping our redline limit around 7500. seeing as how the upper region of the RPM scale is already cut off from the factory.

Isn't increasing bore pretty hard? You have to have a new liner and stuff right? Increasing stroke is probably not a good idea here since we're already so low on rod length.

HomemadeWRX/3MI Racing said he is working on this. I think he hasn't gotten a shortblock yet, but his thoughts were I believe new pistons with higher wrist pins, and longer rods, possibly eating up some deck clearance. We need 9-10mm of rod or so to get into "typical" high rev engine territory, which seems like it won't happen :/ I don't know how much rod length actually matters for durability and friction, but OEMs are clearly not willing to push to 8000rpm on less than 1.6 rod stroke ratio.

Has anyone looked into the stock cam profiles? Does it look like they'll make power past the 8000 rpm range?

Ah, dug this gem up: http://www.purcellperformance.com/Te...13%20FR-S).pdf

Those are Toyota's specs, which are not the 0.050" lift or whatever, but just compare with known specs for say 1NZs or something and you'll get the idea. I get the feeling that these are pretty conservative cams meant to maintain acceptable low end torque, because the duration is only a tiny bit higher than the 2GR-FSE (assuming their diagrams depicting cam duration are consistently drawn).

Now that I just saw that diagram again and remembered, the stock VVT system lets you open the intake valves 24 degrees ATDC! PLENTY of room for high duration, high overlap cams then :D

Nice! Yup so should be easy to gain some reasonable top end pull while loosing almost nothing down low.

Eh dunno about that, increasing high rpm power means the intake valves will need to close later. That'll lose power on the low end, but the upside is that your fuel economy will marginally improve if the VVT is programmed correctly :D