Hi,

I'm looking for a set of high comp (11-5,1), lightweight pistons for the L15a7 engine (GE). My main criteria is that the pistons MUST be lighter than stock or else i see no reason to change them.

I'm currently runnin a high-strung N/A setup thus why weight is very important.
My question is do you guys know any brands, company that makes what i'm looking for?

I've been looking around the internet and couldn't find one. Thus i'm thinking of ordering customs ones if possible.

My other question is, what brand should i go to? Cp, Mahle, Wiseco,...?
Have you got any good/bad experience with these brands, or others?

This will be my first time getting pistons for my car.
Any help would be much appreciated.

 

I'm told Wiseco can make whatever piston, in any design you want. They don't make off-the-shelf 11.5:1 CR pistons for the GE though. I asked a similar question, and here's the thread, if you're interested:

https://www.fitfreak.net/forums/2nd-...-question.html

 

JE, CP and Wiseco have an off the shelf either 11:1 or 11.5:1 piston. Im not sure on stock piston weight to compare the two.

btw the l15a1 and l15a7 use the same piston aside from the l15a7 getting a special coating on the piston skirts.

http://www.ebay.com/itm/JE-Pistons-Honda-FIT-JAZZ-CITY-L15A-VTEC-73mm-Bore-11-5-Compression-/201091436126?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ed1fbce5e&vxp=mtr

possibly another option is to use the new gk5 piston from the l15b engine. stock is using 11.3:1

 

Hi, thanks for answering. Okay, i'll contact Wiseco and see if they could make me a set with the specs that i'll require.

Have you used Wiseco pistons before?

 

Hi, thanks for the info, i'll ask those companies about the weight.

I didn't think of the pistons from the L15b engine! I will definitively look this up, i hope they've made improvements on the design of the new pistons and that it is lighter.

 

What are you tuning with? If you do NOT have a tuning solution, you should not be worried about piston changes. Wait until you can tune before making large changes.


Im all for 12:1 and 9k rpm out of this motor eventually, but you wont see me buying any rotating parts before a tuning solution

EDIT BTW, you wont notice lighter pistons. aerofoiling the crank counterweights, knife-edging the main weights, and dropping rotating weight at the flywheel and clutch will FAR outweigh any piston changes.


You can worry about super lightweight pistons when you are spinning over 11k rpm

 

Looking on HondaPartsNetwork, this is what I'm seeing.

2015 Honda L15B Piston Weight --> 1.16lbs
Dimensions: 4.37" X 4.37" X 4.37"


2009 Honda Fit Piston Weight --> 0.54lbs
Dimensions: 3.35" X 3.19" X 2.95"

 

Hi, yes i do have a tuning solution, i've been using a Dastek piggyback for the last 3 years. It works like a charm.

True, the mods you said will affect more. I've done them already(shop), the engine is fully balanced, ported,...flywheel shaved and i'm running a 3 puck clutch.

Also raised the limiter, it's now at 7800rpm thus why i'm looking for lightweight pistons.

 

Hi, funny, i saw those too this morning. However, i noticed that the dimensions were stated underneath the "packaging information" section of the page...
Idk if they meant the weight of the pistons or the shipping packaging..

 

Think of it this way, they probably would package pistons the same way, whether it be from the 2015 Fit or otherwise. If they are packaged the same way, the older model fit pistons weigh lighter. Even with the packaging, the packaged older Fit pistons weigh lighter than the packaged 2015 Fit pistons.

 

Lighter pistons may still not have any noticeable effect. Remember, weight loss is a direct compromise of durability.

Have you contacted Arias? They may custom make you some pistons, and if going for lightweight, may provide some input.

They helped a fellow honda guy out when he was building a 1.8 liter D series that was supercharged.

have you considered a camshaft? Much more effective, and cheaper then pistons, even with additional cost of stiffer valvesprings.

 

True, it does look like that.. Well, to be sure, i'm going to a dealership next week to ask them about this, hope they know...

The problem here is that in indonesia, the new GK fit's are still offered with the same engine as the previous model (GE).
I even asked a salesman when are we gonna get the L15B unit and he said that he didnt even know that honda is making the L15B... LOL

 

True about the durability

Well, i'm just trying to improve on what i have, i'm trying to up the compression, who knows, might get some noticeable gains..

Nope, i haven't contacted Arias, but i think i will.

As for the camshaft, that's done too. I have a level 3 bisimoto regrind with valvesprings too and valves. The cam is surprisingly streetable but the springs are way louder lol

 

buying from Bisimoto is pretty much paying twice, as they are actually Weber regrinds that Bisimoto paid them to make.

Bisimoto also has a bad habit of using WAY too stiff of valvesprings. I would not be surprised if they are nearly double OEM stiffness. Ive been at the bad side of two sets, and have seen dozens more effected.

I would ask Bisimoto for specifications on those springs.


Right now, you should be running a Zinc additive to combat the added wear and tear those springs will ultimately do. It is not the first time that Bisimoto has overdone things unneeded

 

Yes! True again!
When my camshaft got back it was indeed packaged from what company i forgot (probably Weber).
The springs were indeed very stiff, my mechanic (from the shop) told me that he had trouble dropping it in and had to do something about them i forgot to make it work.

As for wear, i dont think i will be a problem too much. I only drive the Fit on weekends and on trackdays. Traffic is way way too congested, i dd an auto

As for the cam profile, with the regrind and tune, peak hp is at 7400rpm.
So far, the best cam for our car. The J's racing one apparently has little gains or even at all.

Keep in mind that it's indonesia, its 30C° outside and best street fuel is 95 oktan (ron)

 

if peak hp is at 7400rpm, make the redline 5-600 rpm after it. Take advantage of the stiffer springs.

Its basically a mandatory thing to run oil that will fight the effects though. Amsoil makes some great stuff, as does the racing variety of Royal Purple.

Also, you should be revving higher then where peak power is. That way when you shift gears you fall back into the powerband. so even if redline of 500 rpms higher produces 15 less hp, it means the next gear will be close or in the powerband.

 

Yes, limiter is currently set at 7800rpms. I pretty much shift around there too just like you said, too maximize the powerband.
Recently, i also added closer ratio 3rd 4th and 5th gears from M Factory, the engine feels 'lighter' now and it accelerates faster.

Ok, thanks for the advice, i've been running Mobil 1 5w-30 for awhile now with short intervals. I guess it is time to upgrade.
I'm also running an oil cooler but even then, during track duty, after 10-12 laps on a hot day, i start to feel power loss... maybe heatsoak, maybe the oil is too hot...

Otherwise, it's such a fun car, if only it made a tad more power N/A..

 

Famous last words! If I had a corvette engine in the Fit, I'd still say the same thing.

 

Has this fit been on a dyno yet? I would love to see some documented N/A l15 engines.

 

Call Bill at Gude performance for pistons, cams, throttle bodies, and ported head package, 951 245 7577 or see Gude.com, for 20 years of racing Hondas. Honda Fit parts have yet to be posted on the Gude web page.
All Fit parts were developed by Gude performance on a superflow Flow bench thanks Bill..