Super and stupid expensive, but J's just released a high compression piston upgrade. Pushes the CR to 11.0:1 from the stock 10.4:1. Power is not increased greatly, about 4ps throughout the power band so for the price which I would hope includes installation and if not it is even more CRAZY...¥260400 or at today's exchange rate $3100. I already know going mekatune is not cheap, but it is the method I prefer. Though I doubt I would be going with these pistons if just the pistons are costing that much.

 

I don't know if I should be excited or not. On one hand, it's good that someone's making high-comp pistons for the GEs, but...the price, man, the price.

 

I know right. I want to call J's and ask...ARE YOU SERIOUS?!?! Of course they are not making the pistons themselves either, but when nobody else is in the game, guess you can charge crazy until others come along and knock pricing down.

 

To dig up a dead thread, for that price, you could have quite a few sets of custom pistons made- Mark W.

 

Mahle or Wiseco will make you a bad ass and super light piston to whatever spec you want. Last set of Mahle's I ordered for the Standing Mile high rod ratio motor was only US$650 for all 4 and that was with a whole list of options:

Enlarged, tool grade steel wrist floating wrist pins (only ~110g)
Shortened skirt
+6mm raised wrist pin
10.5:1CR
Oversized, deeper valve reliefs
etc.

Made with a nice light weight material (piston weight minus pin ~315g)

Wiseco makes custom pistons as well, and they have a few like their 1400HD slugs that see 1400whp in Brent Rau's 6 second 4cyl dragster. You can get an off the shelf version of these made for your fit for less than ~US$700

Wiseco already makes GD and GE pistons in a couple different CR's as well I believe..

 

Not to mention, it'll probably take less time than waiting a month or three for imported pistons. Last set of custom Wiseco's I ordered took ~2.5 weeks- Mark W.

 

Bumping cause I'm bored.

If staying NA, I don't see any reason to go through all the trouble of swapping pistons for anything less than 12.5:1 CR. A knife-edged, lightened crank + lightweight pistons/rods would really liven up the drivetrain.

 

^ Agreed, but unless you have your own machine shop to do the crank and hone the cylinders, it's going to cost a LOT of $$, and give you only a few ponies, and a bit of a freer revving engine that now gets worse fuel economy- a hard trade to make if your Fit isn't a dedicated track whore Mark W.

 

I've stated this in several other threads...some will think I'm starting to sound like a broke record...but:

Increasing the CR by 2 points alone should give around 20 whp. While the block is at the machine shop, you could have the exhaust ports optimized for the WR header. Add a SRI and cat-less exhaust along with AEM EMS version 2 to tune the whole set up. This should produce 30+ whp gain altogether.

Bisimoto also ported and polished the L15 head on his CRZ (which should be an identical head) and saw some gains there. He also produced a custom IM optimized for 6500-8500 RPM.

I really doubt the mpg would fall that dramatically...I bet you could still get 30+ on the highway. City economy would really depend on where you set VTEC engagement. I realize that turbo would be cheaper and produce larger gains, but that is not the OP's question.

 

I don't mean to argue, but those numbers are pretty optimistic. For one, porting exhaust ports RARELY sees any noticable gains, even on tiny ported heads, as on many domestic V8's. My machine shop that I used near my own shop wouldn't even bother, as they'd never seen repeatable, dyno-proven results. Intake port matching, however, WILL prove noticable gains, and you can easily DIY it- just tape the intake manifold gasket to the head and use blueing dye to mark where there's extra material. On Honda's, NA, maybe 1-3 WHP up top, with no major loss of drivability.

As for the compression ratio, 20 WHP would be a monster gain in a car that produces under 100 stock. With aggressive ignition tuning for 93 octane AND a 2 point bump, I'd still say 15-20 is tops. Just dropping in higher CR pistons, maybe 7-10, which is still a large increase. Tuning the setup for max power gain would likely bring you down to around 30 MPG highway, which, as we're getting 38-40, is a 20-25% drop for a max of a 15-20% power gain.
And, again, you're talking a $500 set of custom pistons, $1K or so for the EMS, $500 or so for tuning, $500-1K for machine work (depending on how deep you went), plus another $500 for the header and SRI. So $3K for maybe 20 WHP. I just like to play the devil's advocate, and show the dark side of all this I've gone this route with several customer's cars, and the end result is usually something that is less reliable, worse on gas, and only marginally faster. Boost, or just plain leaving it alone, is usually an easier, cheaper, and less aggravating option- Mark W.