High Compression pistons

[EN2_Squirrel]

I was searching and couldn't find if anyone makes high compression pistons. I am looking into a high compression N/A build. Is 250whp too unreasonable? Looking into camshaft if rules allow? Street Modified scca solo rules

[Xero-Limit]

Hmm...you're starting with 12.5:1. I suppose you can try 13:1 or maybe 13.2:1 and keep it together, but it is going to be a lot of expense for rather smaller gains. I think with some cams, intake manifold, big runner header and exhaust--you can shift some of the power band from down low to up top and get to 250. But the CR is a very small component of that when starting with a 12.5:1. We tune World Challenge cars with 2.5l mazda motors that start out as 9.5:1. Going to 11:1 gets us less than 20 hp generally. And that's a more substantial jump.

[Panda Mao]

the fa20 motor is already high compression from the factory in my opinion 12.5:1 is insanely high on stock motor but considering the technology we currently have and with direct injection it all makes sense oem wise.

If this was an older motor (maybe 10 or 20 years ago) to even reach 12.5:1 from let say 8.5:1 is a huge jump not to mention other things that have to be addressed like timing and fuel as well as physical mechanical things like valves from hitting the piston crowns etc etc. So ya even if it was possible to go higher than the stock compression it would be financially pointless for probably less than 5 hp gained.

[marcoaferrer]

JE makes some 13.5 cr

In 86 and 87mm bore size

https://www.jepistons.com/Catalogs/S...baru/fa20.aspx

[Jason@DSG]

Originally Posted by EN2_Squirrel

I was searching and couldn't find if anyone makes high compression pistons. I am looking into a high compression N/A build. Is 250whp too unreasonable? Looking into camshaft if rules allow? Street Modified scca solo rules

Just make sure you mod everything accordingly, ESPECIALLY cooling. As mentioned, this engine is pretty high comp OEM so going up even more you'll really need to be careful as tuning will be knife's edge if you don't do all the supporting mods.

We can get custom pistons made from CP or JE, CP is a great choice

[SirBrass]

Originally Posted by EN2_Squirrel

I was searching and couldn't find if anyone makes high compression pistons. I am looking into a high compression N/A build. Is 250whp too unreasonable? Looking into camshaft if rules allow? Street Modified scca solo rules

Getting that NA from the FA20? Yeah, I think that's unreasonable even with higher compression. If you go much higher and run advanced enough timing to get to 250, I speculate that you'll be pushing the knock boundaries of even race gas, if not exceeding the physical capabilities of the motor and thus blow it up in the attempt.

Now, if they come out with a H6 FA30, then 250 NA would be completely doable, I think.

[marcoaferrer]

I think 250 is deff doable with people breaking 200whp with just intake/full exhaust and e85.

If you can get your hands on a stroker kit some cams maybe the crawford power blocks and some 13.5 pistons I dont think its too crazy of an idea


You just need to be prepared to run e85

[tahdizzle]

Originally Posted by SirBrass

Getting that NA from the FA20? Yeah, I think that's unreasonable even with higher compression. If you go much higher and run advanced enough timing to get to 250, I speculate that you'll be pushing the knock boundaries of even race gas, if not exceeding the physical capabilities of the motor and thus blow it up in the attempt.

Now, if they come out with a H6 FA30, then 250 NA would be completely doable, I think.

One can only dream.

[SirBrass]

Originally Posted by tahdizzle

One can only dream.

I'm dreaming of an FA30 H6 hybrid port/direct injection motor in the midengine.

Subaru shall call the car: BMZ

And we shall love it, and drive it, and race it, and drift it and call it George

[michael_king]

If you want 250HP and to run in SM why not just go twin-screw w/ 70mm pulley for the same result?


Sent from my iPhone using Tapatalk

[MAPerformance]

Follow this thread

http://www.ft86club.com/forums/showthread.php?t=63901

[EN2_Squirrel]

Originally Posted by michael_king

If you want 250HP and to run in SM why not just go twin-screw w/ 70mm pulley for the same result?


Sent from my iPhone using Tapatalk

I want to do this car N/A. Seems like it would be more fun that way. when drove @whataboutbob 's car there still seemed lag even with the innovate kit. the torque came out of nowhere and then i was backwards. still alot of fun though. the torque wont come out of nowhere(if anywhere) this way.

[tahdizzle]

Originally Posted by michael_king

If you want 250HP and to run in SM why not just go twin-screw w/ 70mm pulley for the same result?


Sent from my iPhone using Tapatalk

Because 250 whp NA twin > 250 whp blown twin.

[Jason@DSG]

E85 or race fuel will be possible but it requires a full engine build especially if you go up in compression, and major cooling and a REALLY good tuner