Resources for NA high performance engine builds?
 

Does anyone have links to any NA engine builds on here?


Some general questions:

How much is it possible to increase the bore on the FA20?

Any tips on what to go for in terms of donor engines? Would an engine that's thrown a crank bearing be a good candidate or something to avoid?

With what (general ballpark) costs should one calculate for components alone?

Would 250 crank hp be achievable on pump gas?

Hey there,



As a rule of thumb we like to see a max overbore of 1mm. Obviously that is a very small change so there isn't much to be gained there.



As far as a donor goes look for a motor that had an issue with the heads but make sure the bottom end is perfect. its much cheaper to find a set of perfect heads by themselves.



Ballpark on components can be from 2500 for the lowest of low-end to 5000 being all the bells and whistles.



That HP level on pump seems too optimistic due to the amount of compression you will need to make it.

What power levels should you expect to see? If you went to E85, how much would that change things?

So I have a question about doing an NA build that I've been wondering for a while. More extreme cams have been available for this platform for a while now from Piper, but I know that the stock piston to valve clearance is so minimal that there really isn't any room to upgrade the stock cams while keeping to stock pistons. So, if you want to go to a more extreme set of cams, I assume you need custom pistons with deeper valve notches? If so, is it possible to retain a high compression ratio or are the cams mainly aimed at people with boosted cars and lower compression ratios (which I assume would have more valve clearance than higher compression pistons)?

At some point in the not so distant future I would like to do an engine build of some sort. I'm competing in NASA's ST/TT4 class which has a power to weight ratio of 12 lbs per avg wheel hp and right now I'm at more like 13.3 making about 195whp avg (205 peak) and 2600lbs competition weight. I'm pretty much out of things to do to make the car lighter without spending obscene amounts of money for dry carbon replacement pieces so I would really like to be able to add like 20whp to the car. I feel like that should be possible to do with an NA build on E85 with some valvetrain work, cams, and a better intake manifold (the Jun one shows some promise for opening up higher RPM range). That being said, no one has been able to make much more than the 205whp that I currently make that I know of, or if they have they haven't shared their results yet. Just trying to figure out if making 220-230whp is feasible in an NA FA20.

I would say 220-225 with 13.1 compression with e85, ethanol is pretty much required due to the compression you are going to run. any compression above 13 is out of my knowledge on these motors.

Hey there,

That's mostly correct when you do the cams you'll need to work somewhat closely with Carrillo ( my preferred company for custom pistons ) so that they may make it clear the valves and keep the size of the piston reliable.

you really are going to need a custom 13.1 compression piston/cams and most definitely and most importantly e85. @celek is doing a more extreme form of an N/a Build check him out.

If you go with the average dyno for stock non 2017+ cars, they get about 165whp from 200hp. If you take that loss and apply it to 250hp, that's about 206whp.

You should be able to get almost there with an ACE header, full exhaust, good intake and a good tune. People have hit 199whp on california 91 with the ACE header, getting a couple more on 94 octane should be doable.

Has been done already on a roller (we got multiple dynos at various locations to play at any given time) by yours truly and has been tested at various tracks back to back. Engine still runs fine and numbers are still solid. :)

Blue Moon Performance built me a forged internals and WPC coated motor that has been bulletproof. They have also built a number of NA and FI FA20 race motors for competition use as well as building a number of motors for professional race and drift teams. I'd shoot them an email and see what they suggest.

http://bluemoonperformance.com/

I'm holding out for 4Piston.com to start building long blocks for us. Or at the very least develop a killer head program. I can build my own short block.

Back in the day to tweak more HP out of an engine was to build a stroker. But the new modern engines (Japanese) are built to such tight tolerances and engineered to tight specs a stroker just may not be worth the cost. Saying that, and when we didn't have the money to stroke out a V8 we had other things done such as;

Head port and polish
Changed the intake to a higher flow
Larger carb to match the extra air going in. Holley double pumper
Auto trans was rebuilt with tight clutches, higher performance Torque Convertor, shift kit (to "chirp" second gear with), trans cooler and best fluid we could find
Rear gears went from 3.23 to 4.11 or 4.56 if you're brave enough
AC delete
Larger Radiator
Cooler thermostat
Headers and Borla Mufflers

Now a lot of that is still applicable to todays cars but the fuel air stuff probably won't be effective without telling the computer you're getting more fuel and air. For me I'm going to do a lot of these things over the next 1-4 years. That's the fun with these cars. Trying something different. Trial and error.

Hey @stevesnj you're stealing MY thunder ...... :slap:

(BTW, you forgot the high lift cam .....:))


humfrz

@celek

so much @celek

Oh yeh, I had a 66 327 with a solid cam and lifters. That thing loved to rev. :burnrubber:

Thanks for all the replies. Ok, I found the thread from Celek. 2.3 liter is more like it. :D As far as I can tell he is not done with it yet?

I suppose a build like that is more like 10k+$ and an endless amount of time investment. Will be very curious to see what kind of power that can make.

Would a less extreme version be doable for normal human beings and on a more limited budget? Like sleeves to increase the volume but on stock crank and some head work to increase the rpm?

I think heads/cams/intake manifold that make power north of 8000rpm (and rockers that don't blow apart) are the key to making big gains NA. The manifold gets interesting with runner lengths and the distance between heads.

....and bonnet clearance. @Tor the 250hp (crank) is more easily achievable without opening the engine, definitely if you have access to E85. These guys going for the mega builds are looking at attempting 250whp, near 300hp in our terms.

Intake runners are your obstacle for revs.

The head needs no work for a budget NA build.

The stock valvetrain will hold up reliably to right around 8k as long as it's not a '13 motor... Oh, and around 8,400 the oil pump gives up anyway.

Even with sleeves you're only getting .1 liters out of overboring. Not worth it without increasing the stroke.

JUN proved that simply shortening the runners at stock diameter carries the torque curve up by several hundred RPM, which reflects as a proportional increase in power. Something I have said for years.

If I was doing a budget NA build on an FA20, it would be ACE header, tuning & flexfuel, stock unopened motor, make (or have made) a custom aluminum intake manifold with shorter runners... Think 15mm shorter. A simple one with tubular runners, hand milled flanges, and a sheetmetal plenum.

Tuning on ECUTEK with a rev limit of 8000.

Throwing blind darts, I'd bet very safe money on 210 peak WHP on pump gas. 200 if you didn't touch the intake manifold... (But then you wouldn't raise the rev limit because there's no point doing that NA until the intake manifold is addressed. Moving an identical torque curve to the right is what makes the extra peak power.)

Oh, and it's worth mentioning I'm speaking in terms of repeatable, uncorrected dyno numbers on an accurate machine. E85 is getting into guesswork territory but I figure another 5-8%

...Any reasonable amount of extra money would buy you only disappointment.

Beyond that, the classic Subaru exhaust ports are going to be the choke point that becomes a hard limit.

Now here's the caveat. Find someone similarly knowledgeable who disagrees with me... And isn't trying to sell you a product.

This sounds very interesting and actually doable with a budget similar to a basic FI setup, correct? Would you say that this setup would hold up to track usage better than a FI one or worse since we are upping the rpms?

I'd say doable on the same budget as a basic NA build plus about 1000 for a good fab shop to make a well-built intake manifold for you.

That would put it between an NA build and a low-budget FI build... And between those two, I know which one I would be willing to thrash on a track without the constant fear of blowing it up.

Oil cooling is the only additional necessity for track use.

Buying the actual JUN manifold will set you back over 2k, and then we're getting into FI-money territory... But it makes power with proven theory that holds up in the real world, not smoke-and-mirror snake oil bullsh*t.

No I am not done yet.
But time and money are a constraint.
I have been working with a couple companies on being able to have them offer a kit at less of a cost. The issue is you have 1 set of rods/pistons made at a time the cost is 20% higher than having 5 sets made at once.
Keep your eye out on the market you may see a more affordable version of mine for around $3500 in parts to make a 2.3 liter

Kinsler needs to make a proper ITB setup.

Piper Cam installed. :)

https://scontent.cdninstagram.com/t5...97744640_n.jpg

So a spare engine wouldn't even be necessary. What about pistons, would there be any advantage with going with forged pistons in such a scenario.

And if having a 2013 engine (like I do) what needs to be changed?

Who is JUN?
*edit* Is it this you mean?
http://www.junauto.co.jp/products/su.../index.en.html

If not doing the intake and raising the rpm, and not using E85 (which I don't have available anyway), that leaves just the ACE header and a tune, or am I missing something? I think that would get 180-190whp at best?

That sounds interesting and an affordable price point that brings it into (or below) FA territory. I liked your FB page too. Looking forwards to updates and seeing it running! :bow:

1. Rocker arm pivots. In short, your engine has 2 sets with 2 different part numbers. Half are a bad design. Also gives you a chance to check and make sure none of your roller pins are backing out due to poor swaging / poor QC. I'll have to go dig though old stuff to be more specific than that.

2. Yes, that's the JUN I'm talking about.

Here's a link to the original thread. The math in there explains why it works.

http://www.ft86club.com/forums/showthread.php?t=110517

3. Yep, leaves ACE and a tune, but it'll do better than you're guessing. Oh, and a drop-in filter if you care... 199 WHP can be done consistently on a normal dyno (not a hero-run on a dyno) on just that... With normal-people pump gas.

Every NA hp after that is an expensive diminishing return.

Thanks for the link! What is the disadvantage? Why is no one else offering intakes like this at a more reasonable price? Seems like an obvious thing for someone like Racer X fabrication to get into ( @Jeff@Racer X Fab ).

I am skeptical about the 199whp on E0, of course, depends on the dyno and stock baseline. That's why I prefer crank hp for comparison. 230 crank with just an ACE header and tune I would suppose is the absolute maximum. 199whp in my baseline would equate to 250 crank.

All this NA talk makes mehttps://goo.gl/images/dduh3N

I wonder how much capable the 17 motor is with the headwork, cams, and intake manifold from the factory is...

Yes, it would be awesome if RacerX did a similar manifold, without the "JDM" markup... Now that there's a proven one floating around..

Velox was working on a unicorn intake a while back but the design didn't work out, and it got lost chasing unicorns.

Making and marketing an intake manifold is an expensive and difficult experiment for a small company, with a huge potential to blow up in one's face.

Regarding disadvantages, heat soak is one. Plastic is a vastly better insulator. It's not a major disadvantage, and it's not a major effect especially at WOT. But the internet would have you believe it's like pouring sand in your transmission oil, so...yeah...

The 199 WHP number I'm referring to was determined by CSG, and the baseline on the same dyno was 166 WHP. You can calculate the percentage gain if you want.

It's not completely fair, because on ACN91, both the baseline and the tuned version would have been down on a small and not necessarily consistent amount of power from ignition retard.

I'm not big on reverse-calculating crank numbers. I understand the desire to have a perfectly consistent medium for comparison, but there really isn't one. The dyno's all read differently, and getting from WHP to crank HP, you're just extrapolating even further. All that any dyno does is measure tractive effort (Torque) at the wheel or axle. Literally everything else is calculated, and they all use the same equations. Any "error" comes from how accurately that particular dyno reads torque.

Anything beyond measuring gain relative to your own baseline is getting a bit close to "dyno-racing" for me.

RacerX already make intakes for a lot of other cars. That's why they sprung to mind.
Hence, I don't believe the 199 from CSG is useful. But it doesn't matter, it's pretty well know, that a tune and a proper header will land you in the 220-230 true crank hp region. The reason I opened this thread was to see what you can do to go further. I never thought about the intake manifold as an option so thanks for pointing that out! :thumbsup: Personally, I don't have any experience building engines and would know even less about making an intake. So I would have to wait for someone to make one available (The JUN is too expensive for my taste).

Are there any gains from upgrading the front pipe with an ACE header?

...I have no idea

:iono:

I do know that there's HUGE gains to be made in the noise, rasp, and unpleasantness department if you don't keep a resonator or at least one cat in that replacement front pipe.

My thought was JDLs ultra quiet front pipe with the upcoming ace cat back.

https://www.facebook.com/permalink.p...bstory_index=0

Saw this on Facebook, wondering if similar appplication can work for cars?