Re: My Honda City Vtec - RRP Dyno report - Graph included Quote:
Originally Posted by The Wolf Sorry for a late entry...Congratulations Joel, job well accomplished!!!
Though my expectation was a little more from the ecu tuned state, I dont have too many reasons to believe that this may be the best the ecu could do for the given setup. Just a suggestion though, why dont you have RD Karthik tune a couple of dyno runs for you, if it has to add anything, so be it, aint it?!
Hey, I am not doubting your tuning capability, pls dont get me wrong. I am only thinking that he may have something more to offer as its his own development. Just a guess.
A 4x2x1 header design can never out do a 4x1 when it comes to peak torque and a 4x1 can never out do a 4x2x1 when it comes to an average torque rise throughout the rev range. Tried and tested theory, many people have tried defying this concept and very few have ever succeeded! 4x1 headers are easier to build and works well when it comes to race usage as the application requires power gains only in a particular revv range. The fun begins when you start building 4x1s with varying diameter pipes through the length (Bisi showed the world how thats done) and rework the lengths accordingly. Forgot to add, there is so much to gain from the collector cone design- Internal structure, length and volume |
Phew, missed on this all these days.
Thanks for those words Ritesh.
Yes, there is a limit to which you can push an engine, without touching it and with only the external addons. 12bhp over stock @ the wheel is decent I guess. Optimising the entire intake and exhaust system to make it work at its best and getting the most in the end with electronic aids is the best one can do. I'm happy that I have got there very well dirtying my own hands, as I had planned and indeed some of the tricked cars have trouble keeping up with mine. On the dyno and off the dyno.
An ECU in a petrol engine can only do two basic things. Ignition and fuelling.
No matter what the system is, the values that factor the engine are the values that you punch across your cells. Based on experience, engine knowledge, engine requirement, engine limits and physics. They dont change if you developed it or not. There is a limit to what you can pull off a stock engine with an ECU, especially with a petrol engine. You cant make power adding insane ignition and fuel. Having spent 2 hours on the dyno and varying every possible parameter, its very clear. So much that I didnt even spare trying to pulp out the last 0.2bhp from my second last map and that was gained after 2 runs. Most aftermarket maps have problem even keeping up with stock maps. I'm happy I gained nearly 3 horses over stock. The stock Honda maps are very good and are not easy to beat.
My major gains were from my hardware changes, primarily coming from my exhaust.
Built in over a week with a complex header, collector and muffler deisgn is what you see on the dyno chart. The torque gains are right off the idle and the band starts really early yet with an aggressive high rpm band. With the area under the curve much higher than stock, do we need proof enough if my 4 x 1 system is working or not, I dont know. The dyno curve is your biggest reference. I've gained nearly 20nm more torque over a stock engine at peak and proportionally across the rev-range, starting off idle. All this, yet keeping a solid top-end punch. Which is why I needed over a week to finish the fabrication and a good amount of time for me to plot the design in my mental simulator. Driveability is good enough for me to mostly assume that the car is automatic .
Tempted to touch the engine now, but no time. Next racing season is starting soon. Last time I checked even the tappet clearance on my engine was never. 90k run and still strong. |