My previous car was a Cobalt SS/SC with alot of mods, one of which was HP Tuners. To those unfamiliar with that program, it allowed modification of everything the pcm used to run the car, injector swaps, afr changes, spark, etc. So Im a bit bewildered to see that the only support for a HONDA is from Hondata and they only support the GD. Why? They are still making the GE8 and only the GD in the US for what 2 years? Ive emailed them and they said they are not planning anything. Thats a pretty poor business model IMO. Support a discontinued car, but not the current model. I am painfully aware that even a year change in the operating system on a pcm can throw a massive wrench in things.

Which leads me to something I have read time and time again on here. That the pcm will adjust itself and power mods unless F/I are useless.

Why?

Removing restrictions irregardless of location (i/h/e), should make power. So does it, and if so why is all I hear that the L15 is such a dog?

Remember the D series? Yeah look at those motors now. You would have been laughed at for an all motor D, but here we are with a 10.4:1 CR 16 valve I-Vtec motor....bitching about the lack of performance.

So..........whats the real problem with the motor? The motor or an aftermarket unwilling to support it?

I say the aftermarket.

They have us bent over a barrel charging rediculous prices for a pipe with 2 flanges or whatever, then justify it with calling it R&D. With the exception of some parts most of this crap is basically stuff a muffler shop could make.....(which may not work for those stuck on build quality and think ALL welds have to look like stack of dimes).

Once people make this stuff simpler, and cheaper. The rest will take care of itself, maybe Hondata with support a car STILL in production. Just my opinion.

 

Cool story, bro.

 

Now thats out of the way, any input worth reading? Lol.

 

There's one big difference between the GD and GE L15A mills - and even the GD1 L13A3 vs. the GE6 L13Z1. It's the exhaust manifold.

On the GEs Honda borrowed a trick from the FA/FD Civics and molded the exhaust manifold straight into the side of the engine block. On the GD this wasn't the case; you can buy aftermarket exhaust headers that were actually shaped 4-2-1 and weren't glorified downpipes.

Even so, it's also a matter of differing priorities. The L-series really was meant for fuel economy first and power second. The original GD Fit engine, the L13A3 i-DSI, used every fuel-saving trick in the engine-maker's book this side of the Atkinson cycle, and the L15As that followed after were simply an extension of the same theory but with a VTEC head thrown in. Eventually with the GEs Honda threw out the twin-spark i-DSI system and went with i-VTEC on all L-series motors, but still largely followed the same brief.

All I'm saying is don't expect any high-power aftermarket miracles like the D-series used to bring. The L-series lumps were designed by Honda to be very different birds, to very different priorities. Short of boost, maybe there just isn't a lot of power to be squeezed from the modern L15A7...which is why a K-swap is probably your best bet.

 

GE's biggest problems are the Cylinder Head, and the ECU. In that order.

You want to fix that?

Get a group like dart to make you a billet head with better valve angle, non-integrated exhaust manifold and no coolant jackets so you can do with it what you like.

Till then, find a cam with a big ramp/duration that compliments the retardedly small ports on the head, close down the IV/EV overlap and boost that fucker.

The GE is not a great base for performance mods, the GD is. Cry some more, or do something about it lol

I have clients making triple stock output on stock head/cam, but they put their money where their mouth was

 

Im sorry, but have I offended you in some way? Your first post was sarcasm, then followed up with sly references to crying and then suggesting I am not putting money where my mouth is? Im new to this platform, and enjoy it for what it is. Im not trying to make triple the output, just something a llttle faster. If I want to go balls out, sure I will swap. Im not sure where the hostility and tensions are coming from.

 

Let's boil this down a little more.

With any performance tuning you are seeking to create a more optimal setup.

Theory:
For any given displacement, you have a number of means to make more power. You can increase cylinder pressure (forced induction), you can increase torque made at any given point on the curve, you can rev the engine higher and make more power. But of course all of these are subject to some limiting factors that you have to address. If you want to rev to make more power, you need to make sure that the per-stroke power (which is torque) doesn't drop off because (for example), you cannot suck air in or exit it fast enough, or you can't deliver enough fuel in an increasingly short window, or the valves can't open and close fast enough.

Note that I said "For any given displacement", because usually we don't mess with that. But you can, if you think that's the factor. You can bore the head to make it larger, you can put in a bigger engine, maybe there is even some benefit to a head with more cylinder volume.

Practice, mechanical:
And getting more specific, each of the above approaches is just great in theory, but tricky in practice, even just mechanically. Sometimes it's easy to get equipment that fixes issues: higher-flow injectors, no problem! Bigger valve openings? Hm, in that case I need to bore the ports, and then I need bigger valves; are these things available? Maybe it's simpler to get a new head, but is there a higher-spec head available that I can bolt on? (That move will be familiar to D/B series fans!) Is it the exhaust manifold that I can replace with a better one (no, in the case of the L).

Practice, electronic:
Then you have to think, what makes all this stuff work together properly? This isn't a 1989 Merc diesel that operates entirely mechanically; there are integrated circuits delivering sensor readings to a flash-programmable processor that responds and then sends commands back out. The ECU is going to respond thinking that it has the same injectors and airflow rates and a number of other constants. So that needs to be changed. Do I have the code for the processor ie do I know what's on there already? (No.) Is there an IDE so I can modify it? Can I deliver the new code? Hm, that sounds real complicated (it is!), has someone developed a reflash I can buy or a programmable ECU that I can mess with? Is there just a higher-spec model whose ECU I can take and install? (Again, common D-series move).

Always when you're doing the above you're looking for the limiting factors. Even if you don't realize it Probably for a given displacement there is a "most optimal" theoretical setup for power. Straight intake, valves that comprise 100% of the cylinder head, straight exhaust pipe, compression ignition, infinitely variable valve timing. This theoretical engine would be far to big for the bay and to even approach it you'd have to do thousands of little mods. So you are of course constrained by wallet and time, so you focus on what creates wins initially - what one mod will immediately unlock more power? Then you do that, and then go on to the next limiting factor.

Ideally there are just a few, but I discussed a lot above. Why? Because in this case, you'd have to modify a lot of things in order to make more power. Is this bad? Well no, actually - it indicates the manufacturer has already removed a bunch of limiting factors, and it's actually a hallmark of a well-engineered engine. That is the current L-series. It's light, easy to produce, cheap, and makes lots of power given the size and weight. Or you might say, it's the hallmark of a bad engine - they haven't bothered to remove ANY of them and therefore a lot of work is needed to get it up in power. But really it's the former - and most things you would want to change to "fix" it would be difficult after manufacture.

In a nutshell:
1) The Fit is already highly tuned
2) Most things you might change are difficult post-manufacture
3) There are not a lot of feasible (ie preexisting) modifications for the car

 

I imagine DSM is being blunt because this topic comes up all the time but GE folk refuse to ever spend money on things when they do come out or do their own leg work.

 

I see some of you guys keep bringing up the D series motor. Saying that that motor can make big power so why not the L. That motor was in production for 21 years. How long has the L motor been in production, and how about the GE?

 

Good point actually - how much power did the D make after only 5 years in production? I don't know the answer but I know it took quite a number of years to figure out that certain engines needed strengthened pistons, others would have swappable heads with D/B engines. These things only happen when the engine starts getting old.

But with increasing standardization within a family and increasing differentiation between them, I don't think the L will have that development. If anything, maybe the L1.3 folks look at our engine as a source of mods. Until Honda develops some parts (maybe next year!) that increase power/efficiency it's likely to remain unfeasible for the end user.

And then of course there's the fact that interest in cars broadly, especially among young folks, has been falling. The growth of Internet entertainment, socializing and shopping options has driven this. And auto refinement has been going up. So the desire to "improve" a stock car in certain ways has not only gotten more difficult, it's also gotten less important. The decline of car culture is another issue, though ...

 

I don't understand why dudes put the D on a pedestal.

It seriously sucks.

It needs work done to the bottom end at anything beyond about 250 whp.
It doesn't respond to NA mods at all.

It is just like the L15.

 

I meant the D series having started to hit its stride. That happened some years ago.

Gude was a big innovator. I guess the big thing, the real beef I have is this.

Im not a newb to tuning cars, nor to building and modding them. We can compare notes as to who has done more, bigger, or better...thats not gonna solve anything.

My post was really just a rant with a request of input from the community. Its sad that the top 10 posts in this forum havent ended up on page 4 or 5 by now. Same stuff.

Why cant we then, put the head off a GD on a GE....deck the head, port it out......

Why cant we port the GE head? Extruded hone it? Deck it?

I wish we had more. I refuse to spend alot of money on an intake for exampe as all it is is a pipe with a filter, legitimized cost wise by companies who claim R&D and exclusivety.....

Now, someplace comes up with a head package to adress the small ports with a mild cam...or Hondata (Ive have HPT twice now, so Ill buy), or something.....why no engine builds?

If the resulting answer is....nobody will buy it? Then weve done this to ourselves and innovators who diy turbo or what have you are better off.

 

Worth repeating lol

Those problems are like a locked gate. Both can be solved, give it some time.

I don't remember very many guys "back in the day" that had built D series, B series was the answer much in the same way that K series is now our answer.

L15A7 has only been around for four years or so right, three in the US.

I think once someone spends the time to break that gate open things will change. It will happen more slowly now than ever given the state of our economy... people don't "tuner" like they used to

 

You might be on to something there Mike lol

Basically your potential and the way in which the power will be delivered is going to be depend more on the volumetric efficiency of the motor and where it is efficient in the rev range.

As with any fixed volume device/air pump whether its a rotating or reciprocating design, the more cycles over a unit of time, the more air you can displace.

How much power potential you have is a constraint defined by how much air mass you can move in this case. Notice how I am introducing mass in while discussing volumetric functions...

Just because you have 1.5L swept volume does not mean that every revolution at every operating point along the rev range you are ingesting and disposing of a full 1.5L for a full 720* cycle.

The best representation of this reality is the torque curve.

All motor, or forced induction the most dramatic VE modifications are going to be of course the camshaft and the manifolds. Then of course there are the ports, valve area, seats, etc.

Changing a camshaft, just by itself in most cases is not necessarily going to help with more peak power if either the intake or the exhaust manifold is not complimentary to the new power curve the cam will dictate. There is port velocity as well as harmonics and wave tuning to be considered.

Great, so lets go for a big power all-motor build! This necessitates top end power because we have such little displacement, so we have to shift VE (torque) up the rev range to make real power. Horsepower is a function of torque over time. A fixed torque value makes for constantly increasing HP value as rpm increases.

100wtq @ 5000rpm = 95whp
100wtq @ 7000rpm = 133whp
100wtq @ 9000rpm = 171whp
100wtq @ 11000rpm = 209whp

Now, obviously torque is not a constant in a variable system and no matter how much valve lift, cam-phasing and spark timing trickery is employed, all motor applications have serious limitations when it comes to cylinder filling across the entire rev range.

So you pick a power goal, requisite mass flow to meet it and compare that to the massflow that can be achieved with the swept volume at hand with your atmospheric conditions. 100wtq is nothing outrageous or remotely a problem on a 1.5L, its where that cylinder pressure is made that is important to your power figures.

With the resources at hand you can make a short stack, straight shot big plenum intake matched to ports that can handle the volume required at the ambient pressure available (basically the requisite massflow) at a max of .5-.6 Mach. Then dumping it into the cylinder through a complimentary valve angle, using as much valve area as the combustion chamber allows while not increasing the quench to an excessive degree.

After combustion, you need to clear the way for fresh charge to be used on the next cycle. Much like on the intake valve angle, port shape/dia/length are crucial on the exhaust side, as much or more important is going to be the exhaust primary runner.

Now NA motors like a good bit of cam overlap, so to avoid reversion it helps to have the collector a good distance away. As this is a max effort NA build you would want seemingly excessively long runners, and bring them back together through a sort of concentric reducer akin to a Laval nozzle.

The idea here is to seperate pulses from cylinders so there is no reversion from one to the next contaminating the charge and hurting VE. Additionally the tube diameter and length are to be tuned to the RPM range you are aiming for so that each pulse pulls the next one along using the low pressure zone that follows each "puff" leaving the cylinder.

This is what is referred to as scavenging on a 4 cycle gas motor. Too much tube diameter and charge face velocity drops below optimal, too little and backpressure will cause the motor to fall on its face as mass flow increases.

The fact that the GE cannot be modified on the exhaust side is what holds it back the most. The exhaust header in this case not only dictates the power curve, but peak power as well. No amount of cam or intake can remedy this.

The GD does not suffer from this. Additionally it is older and more affordable for real tuning.

So the potential is there in more ways than one for the GD, the GE ... not so much. This is not a debate or opinion, this is reality.

Meaning it most certainly makes more sense to support the aftermarket for this car. Even then the GDs have had a greater proportional demand for actual performance mods, yet so few of them follow through.

The GE crowd, while greater in number, has followed through in yet lesser frequency than that opting for plastic bits, fart cans and wheels.

My own anecdotal observations confirm this as well.

OP Consider that your opinions on their business model may be entirely off, unresearched and unfounded.

 

If? This is quite clearly the case. The people who buy economy cars new are people who are conservative with their $ - either because they haven't got a lot of $ or because they don't want to part with very many of their $.

Yes, there is a whole range of people who buy the Fit, but not that many are the tuner-friendly 24-year-old males with lots of disposable income any more. That post-college-gainfully-employed demographic has been drastically shrunk as the US economy contracts and young people take jobs that allow well below the quality of life their parents had. I won't say these people don't exist - they do - but in lesser numbers. There are teenagers who live at home and don't yet face the financial burden of their life, but they go to school and graduate and find they need to pay rent and taxes and transit passes and Tibetan dumplings for the hipster gathering with their peer group that increasingly is embracing public transit rather than car ownership.

Those who DO have the means gravitate towards factory performance mods, which the automakers have gratefully embraced. HFP, TRD, NISMO, JCW, SVT, M, AMG, STI ... all make a selection of expensive bolt-ons that have great quality and won't void the warranty. Why bother with improving the capability of stock engines when they're already so good? It should not be a surprise that there's an increasingly small market for "high end" comprehensive tuning solutions, and that the price of that work has gone up as the complexity has increased. What you're talking about isn't a problem just for the Honda Fit. It's emblematic of a broader shift in taste and consumption patterns. Do you see a lot of people modifying the engine in their Civic? Accord? Subaru Impreza?

I'm going to go with no, and I'm going to go further and suggest that as a general theme, the remaining "enthusiast communities" are usually attached to cars that are marketed as performance machines in the first place - Civic Si, Impreza WRX, Mazdaspeed3. And that most of the people involved spend a lot of time talking about what performance pieces they are going to buy from the manufacturer of their car rather than thinking about how they would go about improving performance in the absence of bolt-on peripherals.

 

If you want power, I can design you a system that will make it. You will just be severely disappointed if you think bolt-ons or an all-motor build will do anything thats worth the cost

We need an aftermarket cylinder head.. or if I had the resources I would be curious to see if I could bolt a GD head on a GE block, then run a GD Flashpro ECU in parallel with the GE8 computer

I think there may be differences in the oil and water passages.. The OE gasket kits between the A1 and A7 have different part #s (06110-RME-A00 v. 06110-RB0-010), Bisimoto has a single link to a 74mm HG listed for all L-series including the LEA1.

I don't know that I have had both on hand simultaneously to compare.

 

I still dont understand why we have so many people complaining about the GE's and not making power.

I thought we all understood that the aftermarket for L15's wasnt that great because of the base design of the engine. Thus, no aftermarket support.

Ontop of that I thought it was well noted the reason 90% of Fit's are sold. Fuel Economy and cheap to own/reliable.

Jesus people I really wish these kids stopped complaining and went and bought a second car that can make power.

 

Well, I typed up a long reply, but assed it up.

So.

Thank you all for educating me on the oddities of the L world. I mentioned before that I have built, tuned and helped in other areas of my life. I work at a Honda dealer and see/have access to alot of info. I appreciate the refresher courses in engine operation.

As much as internet pride pleads with me to be hard to reason with, and not give an inch. I do have to appreciate that yall have been doing this with this motor for alot longer. And I suppose applying my other experiences with other makes wont help me here.

So. Hats off to the lot of you.

So now we can look at it this way. As one OP mentioned one day we could swap parts with a more HO version of the L. The CRZ guys already are. Think this will help us?

DIY: Honda Fit Intake Manifold in 30 mins! - Page 6 - Honda CRZ Forum: Honda CR-Z Hybrid Car Forums


If nothing else, at least it stirred up some conversation lol

 

Thats the plan, but figured a couple simple mods would make it more fun to bust around in.

 

You make a good point actually; there's a lot more support for the CRZ which of course has the same basic engine (with the very substantial difference of embedding an entire second one inside it!)

I'm not 100% sure why modifications aren't produced for both groups if they're designed for one - most would bolt up fine (the engine electronics are far different however). The "volume" argument doesn't really hold with me - I'm sure a much higher % of CRZ owners want to buy aftermarket parts, but there aren't exactly a lot of them out there yet :P