N/A power output potential as race setup?
 

I have future plans of racing the FRS. I'm looking at a variety of classes and with different rule sets, that means I'm also looking a massive variety of costs. I'm curious about N/A potential in a racing only application but yet does consider cost vs reliability of build. I would like to build something that I can afford to build but also that I can leave at the track in a ball of fire without shedding too many tears. Cuz racecar.

So...

What type of power to the rear wheels is feasible assuming:

1: Mild engine works such as port and polish, blueprint and balance, maybe cams.
2: Lightened flywheel/pulley/driveshaft
3: Race tuning including some increase in redline
4: Race only Intake, header and exhaust (under 98dB) with no cats.
5: Pump gas. No E85 up here and I'd prefer not spend 10-12/gallon on fuel (since racing uses lots-o-fuel).

I know there's some tuners that have played with some race only headers and exhausts but I have seen anyone with ported/polished heads and I don't know what benefits that makes on Boxers.

I think those 5 things on the list would put the build within budget and are conservative enough a build that it wouldn't exclude from too many classes not to mention be reliable and if the car can make 200-215 at the rear wheels that would put me in range of competing in a pretty fun/fast and competitive class. I'd be really interested if those numbers could be made without step #1.

Anyway, I'd like to invite the parts manufacturers and tuners in to discuss what they think might be possible.

Thank you

A couple of people on here have made it over 200 whp without touching any internals!

So far we've got no good info on cams, anyone flow-testing heads have kept that to themselves so port work is also unknown, a proper race header should be matched to cams too.

I think everyone is waiting for someone else to be the NA pioneer.


Also, 200whp where?

I'm going to try to push 200 whp with a local tune, a sweet header and a Nameless headerback with my Perrin CAI. I might get close, but we'll see.

You're gonna need e85 to break 200whp n/a. I'd love to be wrong...

I'm with you on this one.

Also, I'm not aware of anyone breaking 200whp yet even on e85. I suspect if someone had, they would have been posting dyno sheets on every FRS Forum on the internet.

Any confirmed reports/dynos?

Scott

I believe @2forme has a 200whp n/a dyno chart running an e85 tune and other mods...

EDIT: Here's the chart : http://www.ft86club.com/forums/showp...7&postcount=61

I'd love for you to be wrong too.

Also, count me in on seeing who's made over 200whp without touching internals or using E85.

I'm starting to think I'm better off building an S2000.

It was E85, AFE intake, SRT exhaust.

If you bought this car expecting to make gobbles of power on a 2.0 liter NA, then you bought the wrong car. I'd take an 86 over an S2K anyday because I don't spend all my driving time above 6000 RPM. lol but that's me.

Messing with the internals on this engine for an N/A application?

Not sure if the juice will be worth the squeeze...

After the beating I handed two guys with S2000's at my last autocross event in December, I wouldn't want one either.

Scott

You might want @CSG Mike's opinion on the S2000 vs the 86 for racing use if your goal is to be competitive as opposed to just having fun. I believe he stated that with a few mods he's faster in the 86 despite the power differential.

Nathan

It's REALLY track subjective... but overall, the BRZ/FRS is faster.

*edit*

OP has far more experience prepping race cars.... I just set up suspension/aero and drive :p

Unfortunately Autocross is irrelevant to my application. No offense, just a different world entirely.


It's not about making big power, at all. It's about road racing class competitiveness with specific rule sets. Secondarily it's also about finding a balance in on-going racing cost and logistics. If you do 20 races a year on 100octane vs pump gas that's a significant increase in operating costs or if you have to rebuild your engine every season... etc etc. Goal (or hopes) would be to have a 215rwhp race only setup on pump gas that lasts for 3 seasons. (I know, I'm spoiled I currently race a Honda.)

I'm looking at a couple classes and at 2500lbs of car, if I can't see at least 210whp then the juice definitely won't be worth the squeeze because the car won't be competitive. Also, if the only way to make the needed N/A power is to run 100octane or E85 the operating cost changes and once again... juice not worth the squeeze because I can compete with another platform without those types of fuels.

As for the juice/squeeze scenario, thinking about the Spec Miata guys that spend $10k on "spec" engines... The more populated the class or the bigger the event (like national runoffs) the more costs to play up front grow exponentially, thus the desire to hit targeted goal without E85 or race fuel.

So anyway, that's a little background into the motivation of the inquisition. :D

Cams and valvetrain will be worth it and either a stroked/bored (I prefer stroked) would be sweet...

And thus my pre-existing desire. I did buy this car with the intention of racing it at some point. I knew the numbers on paper suggested it would be a very good platform and after having it on track I'm so far pleased. But when you're competing, as you already know CSG, the difference of .5 seconds a lap is huge and thus the calculations start to get really narrow.

Basically I'm trying to measure twice and cut once... or in this case measure 1000 times before spending $50k.

I think cams will be the hot ticket item if staying NA. There's been some data showing the engine can take more rpm, the trick is getting it to breathe up there. With the right set of cams and some exhaust mods, I think 200whp should be possible. Will be expensive though, and a pain to install due to the boxer layout

The question is, how long will it last with an increased redline?

I'd love to see short interval UOA's on an engine with JUST an increased redline, and an engine with increased redline and cams.

No offense taken!

If it wasn't for the TT and Track Day availability here in the Tennessee Valley being abysmal, I would NOT be running Solo events. Slow motorsports is better than no motorsports I guess.

Scott

No idea if its true but with the right cams and tune apparently our valve train can see 9k. i forgot where i saw this but i think Ferrea said something about it.

TRD is in development for cams i saw somewhere as well ill try to find the sources.

There's a difference being not immediately failing, and being able to last 100k miles.

E.g.: F20C in the S2000 will do 9k all day long, but a K20 in a Civic at 9k will grenade after a while (but not immediately fail).

True that. i guess only time will tell us the answer. i think it would be pretty awesome to get this puppy to rev higher i mean it is 12.5:1 Comp. should rev a bit higher dont yah think? i mean E46 M3 S54 engines rev to 8300 and are 13.4:1 granted it is an ITB L6 Double Vanos engine but still sometimes i think they could have made it a 8000RPM redline.

I feel like the engine sort of wants to go more than 7450.

maybe because its like 20 degrees F around here

I'm pretty sure Ferrea meant with their upgraded valvetrain components too. I'd think you'd want upgraded springs and retainers. Ferrea has a few different sets coming out which will work great in conjunction with other engine work to ensure reliability at high rpm.

The way I see it, if you want to rev higher (for NA), you want cams. If you have the engine open for cams, might as well at least get springs, retainers and balancing done.

the stock head and/or cams prevent it from really making power over 7k :(

It's not like the Honda engines that continue to make more and more power as they rev. F20C, not so much, but K20 variants, B16/B18 variants, and F22C...

That is what I'm waiting for too. As some can see, I havn't bought the GT86. I'm always waiting for some racing NA-kit making + 250 PS at the crank. No news from Cosworth yet. An increased capacity engine kit could work, but I'd like the keep 86x86. I don't know why we still have no good NA kits. There are S2K making 300 PS crank NA.

Kind of a tough one to answer, you should know that your build is limited to the rules set by the racing organization. What classes were you interested in entering for the FRS?

Exhaust and intake is usually an accepted modification for all classes, but internals like cams, valves, pistons, rods, etc, arnt always allowed.
IMO you want to get into the chassis & drivetrain building department to get the most competitive edge in any class and race.

If you were going for a time attack deal, running on 2WD Unlimited N/A, for power id ditch the stock ECU and go standalone, bump the compression even higher, raise the rev limit, port and polish heads, and lighten your rotating assembly, low friction parts, larger main port injectors, large aux port injectors, aggressive cams, sleeve the block, advance some timing, Bump ignition efficiency, oil cooler, dual pass radiator, dry sump, block bracing.

Rather than total peak power, id be more interested in getting the engine to respond more to input to plow through corners. To me, if your building a competitive N/A its not about speed, its about rotation.

i thought all the big hp n/a s2000s have been AP2 with the bigger engines F22C.. don't know if i ever saw a F20C with 300hp n/a...

anyway, gotta also understand that the F20C is made to produce horsepower. The FA20 is made to be sporty and livable. Key is where TQ is applied. FA20 scavenges amazing TQ at low revs and peaks again at 6400, while the F20C peaks its TQ at 7500.

If you try to apply the same mods as the F20C, as you would to the FA20, they will respond much differently to them. IMO, the brz/frs will perform much better with more peak hp for acceleration, and sacrifice some of that TQ.

Get some titanium pistons & rods to take on that high compression!

Yep, but doesn't balancing require the entire rotating assembly? May as well say fuck it and do pistons too!

truth, exactly why F1 cars have like no trq but all hp up top its about the cornering and use of the power rather than the trq. you dont want wheel spin you just want rotation increase

Here's what Toyota did with 100 octane race fuel and just a few mods:

http://www.ft86club.com/forums/showt...ota+grand+prix

Add 10hp? My car did that just from aging sucka!

They're typically all strokers, so the displacement is a little moot :p

And yes, I do agree, that the FA20 is rather impressive that it makes 200hp at *just* 7000 RPM.

I'd gladly sacrifice some driveability for more top end hp. AUC for the powerband I use on track is what I care about.

I think 190-200whp is doable on this engine with a budget, around 15k at the most if you do the work yourself. I think the limit to this engine would be 280hp.

But then again this engine in particular has a bit of mystery to it, I don't know any other 2.0 4 cylinder n/a than can scavenge peak TQ at low RPM...which leads me to believe that intake acoustic tuning makes much more drastic changes to the efficiency of the output.

I also don't know any 2.0 4 cylinders n/a that make 200hp or more without aggressive cam profiling like vtek or some serious blueprinting.

if you compare all the engines together in the same class. including the R500 duratec engine, and the K20Z ariel atom mugen. The FA20 with only 200hp is pretty impressive for being an average production engine

Exhaust acoustics as well. No one seems to be paying attention to what I've been saying for some time. You can see it in pretty much every single catless header dyno. The dip 'shifts' in the rpm range and the header makes a bit more ~4800, and up top. The 4800 and top end come from flow gains, but it's the acoustics that move the dip around.

If people want to make mid range or high end power with a header it will be by paying attention to which returns occur at what rpm.

For maximum effect, the same should be done with the intake system and resonators.

This.

You might also want an oil cooler if you plan on tracking your car. Also, lightweight underdrive pulleys would be something to consider as well if you want to maximize power for racing. Getting rid of unsprung weight would be beneficial.

All good points, especially about the F20C. That's part of the reason I have looked at racing a Supercharged S2k as opposed to a N/A one because of how it makes power. The F20C makes its peak power right at the moment you need to SHIFT! It really needs to rev to 10k. Which is possible but then the calculation for cubic dollars spent changes.

But to what end? The CR is already 12.5:1... How much more can this engine go and would that CR increase negate the ability to use pump gas?

Consider a ruleset like that of Improved Touring. I'm thinking the Twins get classified into IT-R when they are eligible to be so (must be in production for 5 years). In Improved Touring you're allowed to balance/blueprint/mill and increase piston size by .040" but you are not allowed to increase compression by more than .5 point. So buying fancy forged/high compression pistons would be unnecessary/disallowed. Also, since IT doesn't allow for head porting or cams then pursuing a higher red line would be an exercise in futility if the stock head/cams won't facilitate it. The problem I see with IT-R is the weight penalty the Twins might receive. Currently the S2000 has a minimum weight of 3005lbs. Awful. I bet if the FRS was classed in IT-R it would have a weight penalty putting it at something like 2800lbs or higher.. ugh.

Other classes are Like SPU, ST (Conference ST not SCCA), or NASA Performance Touring (PTE, PTC..etc). The FRS could be a really fun PT car.

I was hoping some guys like Visconti would chime in and say something like: "yeah, we can do 215whp on 92octane with bolt-ons!" However, I think may have set myself up for disappoint. :(

Lightweight pistons, to reduce rotating mass?

@rice_classic

What does IT say about valves and how do they define porting? If you are allowed valve replacement and seat modifications, you could pick up some low lift flow by going to bigger valves and seating them properly, maybe 5 angle job.