realistically what does it take to get the l15 to 140whp. i have seen this engine boosted and still has trouble getting to 150hp. this does not make sense to me when old beater d15b engines can safely make almost 200hp and those were non vtec. why does the l15 have problems making power?

is it possible to make a DD 140whp NA and if so what is the engines weakest link.

 

the ports on the head are what make the motor difficult to make power on. You need A LOT of mods to reach 140whp on a NA fit.

 

What Chris said. The ports on the head are extremely small. If you want to make decent power N/a, check out bisimoto. Boost is where it's at on these motors though.

 

i've got a daily driven 141whp NA L15 motor... the hard part is there is no surefire formula to achieving this, what works good for others, might no be for your car... so spend time testing and tuning various stuff...

I'll try to best describe my motor (a bit hard since the terms used here is hard to translate and i don't know what it's called down there). The motor has run: pnp, reamed throttle body. i got higher compression than stock, but i'm not sure how much though. temperature is an issue, since i live in the tropics. so i used mugen thermostat with lower cutoff around 84*c. i used chambered open air filter. i use dastek unichip piggyback. i used to use exedy clutch, but have revert back to stock ones. a light racing wheel and good tyres also make that much difference in car response

Now comes the hard part: Exhaust. This one is the most tiring one. I spend a lot of $$$ testing and tuning various stuff... But if you can get a right combination, it works wonder to your car response. I use ORD headers heat wrapped, Kansai downpipe-bpipe, no CC, and HKS mufflers. You can say that all of the exhaust pipings are custom made here. what will be hard for you is exhaust sound restriction. I've got no sound restriction and that opens up a new horizon in tuning a car. I've got stock motor running 120hp just from piggyback and freeflow exhaust (no muffler whatsoever.. just a pipe) and it sounded louder than a jet engine... i have to put on the industrial sound insulation headphones when that car were dyno-tuned.... but don't worry this is a track car, my car still use mufflers. Swapping muffler alone can give various results from 2-15hp difference. Try to find one that best suits your engine condition. And also, try it at the last stage of your engine build. since different motor will require different exhaust piping...

last tuning i get 141whp and 171 torque using RON95 pump gas.

 

can you post up a list of the parts you used and possibly a dyno sheet? i would love to be at 140hp, that would make this the little car an autox beast

 

This would be wonderful, but I think without boost this is gonna be hard to do. Major port work, custom high compression pistons with rods, new valves, etc.... Probably easier obtained by boosting with HKS or Kraft kit.

 

K swap Or do what JCrim did and lose a whole lotta weight. He has spent a great deal of time and energy getting his car sorted with minimal powertrain mods and he KILLS on the road courses.

 

i would like to see some examples of what can be done with a PnP, cam, i/h/e. this is for a DD and there are tons of threads for boosted fits and not enough for NA in my opinion. Please keep boost out of this thread, i would like to see more examples of NA fits.

it seems the intake ports in the l15 are tiny and heavily degrade the performance potential of the motor, is anyone out there doing anything with these heads? Bisi?

 

this. since its a waste of money to try to make power, lose weight instead

 

Bisi sends the heads off to Portflow.

 

There's no reason why it can't make 1hp per CI, without needing to into the bottomend

 

It already makes more than 92HP.

What do you plan on doing there? Lightened crank?

 

DSM, I'm glad ta see ya back in the mix after yur brief hiatus.... but I must say that is the shortest reply that I've ever seen from you. I know all that will change once he answers yur crank question..

 

LOL

ten char

 

hmmm... id like to see a dyno sheet. Those numbers seem off for those mods.

 

what measurement of horsepower are you using? NM or FT/LBS? because there is no way an NA L15 is making over 140 HP in foot pounds. also, is this measurement at the brakes or at the flywheel?

 

HP is believable, but not the tq though. No way a l15 with some higher compression, headwork, i/h/e, and a tune is making as much as a k20 with mods Tq wise. In fact, you'll be hard pressed to find any honda that makes more tq than hp.

 

well, dyno sheet is up on my other thread called https://www.fitfreak.net/forums/fit-...ec-tuning.html... and about the dyno itself is already discussed there, just take a look there... you believe it or not, that's totally up to you.. all i know is i'm the one who got to drive the little car everyday...

btw, sorry for the inadequate technical expertise... my car was mainly worked on by shops in my area, and i'm not directly involved other than funding it and telling them to get the highest power they can get... i just enjoy driving.. and haven't got the time to be a hands-on mechanic.... also sport cars cost devilishly expensive here... due to import tax, etc... example an evo x cost around $133,000.00.... so we're stuck with getting the most out of our regular cars.... and our shops are a master with tuning small compact cars, since that's what the majority owns.... please also be aware that this condition is achieved after 6 years of tuning the car... not a single build project...

 

it's in Nm... what's foot pound? i'm using metric, so i'm having a hard time converting to imperial.... is there a difference for HP measurements using metric or imperial? i thought hp is well.. hp.... horespower... no difference whether your using kilograms or pounds... i might be wrong thouhg... i don't know... measurements is at the wheel... not flywheel, not brakes... wheels... the dyno is a pair of rolling pins in the ground.. the car is loaded on top with the drive-wheel free spinning on the rolling pins... i dunno what you call that type of dyno

 

i've been meaning to ask... what's an i/h/e... i'm really having a hard time understanding your tuning language here...

the list, as far as i can remember:
motor parts:
- top fuel chambered open air filter, custom cold box
- reamed throttle body
- pnp, headworks, the whole gang...
- ik22 sparkplugs
- custom made headers and pipings 1 7/8" front - 2" in mufflers
- j's racing engine damper
- unichip piggyback
- vtec controller
- hks muffler... wanting to convert to kakimoto and see how it goes...
- mugen thermostat

handling department:
- ssr type c wheels with michelin tyres (wanting to convert to yokohama advan)...
- hks s compact coilovers
- j's racing strutbar
- tanabe under brace
- goodridge braided brake hose
- mugen brake rotors
- nissei competition 0-500 brake pads

i was wondering, since you guys are having a hardtime believing i have a 140hp L15... is there probably a major difference between L15 engine for US and the L15 for Asian market? From photos i can see different air filter and different intake... The US have cast iron intake? my L15 comes with ABS Plastic intake... Maybe there are more difference internally? i don't know..