Originally Posted by Shan2nu

An ECU would be your best bet. But personally, just let a high revving engine do what it's designed to do. It would be much easier to change your driving style. All it takes is one downshift!!!

Shan2nu

finally! some practical advice. just downshift.
if you desperately want low end, get a diesel.
you cant have low end, mid range, and high end in a car that is built originally for day to day driving, unless its a big block V8 or something similar.

[nikhilv12]

Originally Posted by kkr2k2

How about going for a lightened flywheel?

Please any one explain the effect of lightening the stock flywheel or replacing it with a lighter one.

raj.

A lightened flywheel will also reduce the low end torque.
The purpose of flywheel, is to keep the momentum of the crank shaft, by adding weight to it. It helps to keep the car moving even when you leave the throttle.
By reducing the weight of a flywheel, the engine will rev faster but at the same time, the RPM will fall faster too.

[iceman91]

Lightened flywheel a strict no no..reduce torque further.

anyway you will get a clearer picture over the weekend

[The Wolf]

Hey hey guys relax, frankly it doesnt matter what you guys feel or think, the fact is that by increasing the trottlebody diameter you are increasing volumetric efficiency and better volumetric efficiency at the same throttlebody position will improve your low end coz more air intake will will force the ECU to run a richer map! Guys get it? Having said that, one more thing here, we are speaking about part throttle application and not full throttle application so power drop due to miniscule drop in velocity is next to nothing!

Summing it up: More air at the same throttle position will result in a slightly richer map resulting in a better throttle response at any rpm. High rpm gains will be even better. However if the application changes to full throttle at low rpm, say you stomp the gas pedal fully at 1000rpm, there will certaily be a very little drop due to velocity drop coz the stock ecu cannot compensate with the additional fuel needed in that quater of a sec when you go from zero to full throttle.

Hope this explanation helps, Im not trying to narrate somthing Ive read off the web or book, its 100% practical experience, on my car as well as being associated with the racing teams and least said my own racing experience!!!

I can suggest you loadz of mods that will boost your low end however I restricted myself to providing you simple, less time consuming 2 rupee solutions. So consider all my suggestions on that basis.

[abhik]

Guys not being biased towards anybody here but just check out The Wolf's garrage, you will know what he is talking about.

@The Wolf your the man bro! My jaws dropped a mile when i saw those figures on a NA car.
Comeon bro share the details and specs please. Bet the engine even if modded is not the one you got with the car.

[RedMM340]

Originally Posted by The Wolf

Hey hey guys relax, frankly it doesnt matter what you guys feel or think, the fact is that by increasing the trottlebody diameter you are increasing volumetric efficiency and better volumetric efficiency at the same throttlebody position will improve your low end coz more air intake will will force the ECU to run a richer map! Guys get it? Having said that, one more thing here, we are speaking about part throttle application and not full throttle application so power drop due to miniscule drop in velocity is next to nothing!

Summing it up: More air at the same throttle position will result in a slightly richer map resulting in a better throttle response at any rpm. High rpm gains will be even better. However if the application changes to full throttle at low rpm, say you stomp the gas pedal fully at 1000rpm, there will certaily be a very little drop due to velocity drop coz the stock ecu cannot compensate with the additional fuel needed in that quater of a sec when you go from zero to full throttle.

Hope this explanation helps, Im not trying to narrate somthing Ive read off the web or book, its 100% practical experience, on my car as well as being associated with the racing teams and least said my own racing experience!!!

I can suggest you loadz of mods that will boost your low end however I restricted myself to providing you simple, less time consuming 2 rupee solutions. So consider all my suggestions on that basis.

To "The Wolf",

Sorry your "explanation" complete with sms language did not help.

First of all, when folks post on an open discussion forum, there is going to be different opinions and thoughts on any particular subject, so it does in fact matter what everyone thinks. Even you. Let's discuss this issue on the merits of the relevant technical parameters, rather than get emotionally charged.

Increasing the throttle body diameter will NOT increase volumetric efficiency. Volumetric efficiency is how efficiently an engine moves the air/fuel charge into and out of the engine cylinders. It is the amount of air sucked into the cylinder divided by the volume of the cylinder. Please refer to the link for detailed description:

Volumetric efficiency - Wikipedia, the free encyclopedia

The only way that your claim of a larger throttle body being able to improve volumetric efficiency is if the current throttle is choking the flow. This is clearly not the case.

In fact the just the opposite of what you say is true in this case. Having a small throttle body will increase air velocity at low rpm thereby improving the volumetric efficiency. If you read my previous post, I had mentioned that some high performance motors will actually have dual intake runners for this reason.

And regarding your race experience. Come on, every Indian driver is a race driver, right? Every time I get out on the streets of Delhi, it is like a stock car race track complete with flaming wrecks and smash-ups. I tell you any Indian bus driver can win the grand prix, if he just was given a chance.

Regards,

Gaurav

[iceman91]

at wolf chill buddy.. Never underestimate the others.. You are not the only one wit race experience or racing team experience..

[Ford Rocam]

I would agree to wolf but only up to a certain extend & only on certain conditions, for eg take indian OHC with d15 engine & a JDM D15 engine, both engines has same bore,stroke & C.R, but JDM churns out 130bhp & indian churns out 106, maybe honda has detuned JDMD15 for indian condition hence manifold, t.b & tuning differ on both engines.
So on a indian D15 engine plug in JDM T.B (its a bigger T.B than indian D15 T.B) a JDM Manifold (manifold design totally different from indian counterpart, in terms of plenum/diameter/length etc) & put up a standalone coupled with good exhaust headers and free flow & tune, you should get close to JDM Power figures, may be more. Increase C.R,Cams,Head porting polishing with a retune via standalone, u should get another 10-15 bhp.

So when ritesh "Wolf" mentioned he got good torque by increasing size of T.B, he is somewhat right but he rediscovered the torque on a engine which was detuned by honda & hence that theory applies to his engine only which happens to be a indian d15.

If i were to increase size of t.b on stock JDM engine to say 68mm, yes the low end torque would suffer from the stock power of JDM.

One cannot apply one rule to all, it depends upon the engine combination which varies greatly, what is needed is to find right combination of parts which works best for a particular engine.

Hope this helps.

[Shan2nu]

But Rocam, do the JDM and Indian D15s share the same cam profile, valve size and ecu settings?

The OHC VTEC's head code is "P2J" which the D16Y6 and D16Y8 heads had. So what we have here could be a D15 block with a D16 head.

Shan2nu

[Torqueguru]

Hi Guys,
I changed my tyres and upped air pressure by 2 psi and i get the feel that its rolling better and picks up better too. Thanks for all the advice, the next thing to do is reposition the intake.
Thanks to you all,
TG.

[Ford Rocam]

Originally Posted by Shan2nu

But Rocam, do the JDM and Indian D15s share the same cam profile, valve size and ecu settings?

The OHC VTEC's head code is "P2J" which the D16Y6 and D16Y8 heads had. So what we have here could be a D15 block with a D16 head.

Shan2nu

Even though if the head shares same code i would physically inspect both the heads together before commenting. unless somebody has done this comparison already & posted somewhere. JDM ECU is OBD1 where as indian ECU is OBd2b.

[The Wolf]

Originally Posted by RedMM340

To "The Wolf",

Sorry your "explanation" complete with sms language did not help.

First of all, when folks post on an open discussion forum, there is going to be different opinions and thoughts on any particular subject, so it does in fact matter what everyone thinks. Even you. Let's discuss this issue on the merits of the relevant technical parameters, rather than get emotionally charged.

Increasing the throttle body diameter will NOT increase volumetric efficiency. Volumetric efficiency is how efficiently an engine moves the air/fuel charge into and out of the engine cylinders. It is the amount of air sucked into the cylinder divided by the volume of the cylinder. Please refer to the link for detailed description:

Volumetric efficiency - Wikipedia, the free encyclopedia

The only way that your claim of a larger throttle body being able to improve volumetric efficiency is if the current throttle is choking the flow. This is clearly not the case.

In fact the just the opposite of what you say is true in this case. Having a small throttle body will increase air velocity at low rpm thereby improving the volumetric efficiency. If you read my previous post, I had mentioned that some high performance motors will actually have dual intake runners for this reason.

And regarding your race experience. Come on, every Indian driver is a race driver, right? Every time I get out on the streets of Delhi, it is like a stock car race track complete with flaming wrecks and smash-ups. I tell you any Indian bus driver can win the grand prix, if he just was given a chance.

Regards,

Gaurav

Dude, lets not get into whose got a bigger one thingie over here! You arent getting my point. When I said volumetric efficiency Im not speaking about engines VE but on the induction part, hope that clears your cliched reasoning behind VE. LOL, you didnt have to pull that wikipedia stuff, really!

Speaking about your comments on the racing front, I got no comments baby, people on the forum know that bit very well since long now. But still for your feel good factor, pull this year mumbai Speed run results and check 1.6L prostock results (wonder why I am explaining!!!), check my timing and position, you will return me an apology on your "every indian is a race driver" and "bus driver" theory, if you got conscience mate! Least mentioned, I am not bothered anyways!

Originally Posted by iceman91

at wolf chill buddy.. Never underestimate the others.. You are not the only one wit race experience or racing team experience..

I was just speaking about my experience, no ways I was underestimating anyone! If you felt that way, Im sorry, the intent was never that way.

Originally Posted by Torqueguru

Hi Guys,
I changed my tyres and upped air pressure by 2 psi and i get the feel that its rolling better and picks up better too. Thanks for all the advice, the next thing to do is reposition the intake.
Thanks to you all,
TG.

Im glad this extremely simple solution of mine worked for you. Believe me there are very simple solutions to complex problems if you just sit back and think!

[The Wolf]

Originally Posted by Ford Rocam

Even though if the head shares same code i would physically inspect both the heads together before commenting. unless somebody has done this comparison already & posted somewhere. JDM ECU is OBD1 where as indian ECU is OBd2b.

Let me clear this for you guys, I have made a physical comparison of both coz I have both the heads with me. Before I start, in d16 there are 2 types, d16z6 and d16y8. The y8 is similar to ours. The z6 has a differernt combustion chamber roof design.

However, d16's at large have a differernt intake post dimension (~2mm bigger), slightly smaller primary and slightly bigger secondary lobes on the cam, and yes the ecu and throttlebody(bigger) is different!

Hope that helps...

Originally Posted by abhik

Guys not being biased towards anybody here but just check out The Wolf's garrage, you will know what he is talking about.

@The Wolf your the man bro! My jaws dropped a mile when i saw those figures on a NA car.
Comeon bro share the details and specs please. Bet the engine even if modded is not the one you got with the car..

Thanks mate!

Wish I could share the specs mate, its a team thing so I dont think I can put that up here!

Surprise, its the same engine that comes with the car I still have in there ;-)

[cancerm]

Originally Posted by The Wolf

One more solution guaranteed to work and wouldnt cost much at all, over size the throttle body venturi by giving it a nice port job and then a shining polish work.

If you have money to put in, get yourself a bigger throttlebody itself and follow the other instructions I have stated earlier like Fuel pressure regulator and heat shielding your filter. You should be more than happy with this!!!

Hello Sir
Just wanted to know would a bigger throttle body have a drastic effect on the fuel economy.

Rgds

[The Wolf]

Originally Posted by cancerm

Hello Sir
Just wanted to know would a bigger throttle body have a drastic effect on the fuel economy.

Rgds

No, not really! You are just generating a wee bit more power a little lower down the rpm band at part throttle so it will not affect your fuel efficiency as long as your driving style remains consistent.