[chetanhanda]

Originally Posted by abhibh

Ok one question.
How do you guys calculate the power gain ? I mean how can you say that by installing K&N + Free Flow etc you have thing much gain in BHP ?

1stly we would prefer to see the power at the wheels not at the crank.
numbers from a loading type Dyno would be nice..

[ananthkamath]

coming to cone filter installs. I dont understand why people (maybe i should say tuners) can be so lame as to put the filter directly in their engine bay where it sucks in hot air? Without any kind of heat shield.

If I do an install in my car, this is how I would do it:



The shiny box is a heat shield-cum-plenum chamber for the cone filter inside. The chamber is ducted to the bumper so only cold air goes in. And its insulated with fibreglass making it impossible to heat intake air. Making it a true "CAI".

[Psycho]

- more air more fuel more power
- for that you need better flow and better combustion

Now you need to open the engine and there the bolt on dreams in for a walk. But hold on you could get 25 horses though the trick is to get a petrol car for which loads of after market parts are available and its displacement is over 2 litres at least.

[drpullockaran]

Please go to this site if you want to stick to ordinary stock cam shafts and yet have a flatter torque curve. The idea is to get the diameter of the steel tubing and length of the tubing spot on to be able to use the stock cam shaft which entails converging on a length and diameter which will not change where the torque and bhp figures originally peaked. If we stray away from the peak torque and bhp figures then it would require us to change every parameter the engine was designed to run at. The secret is to get a flatter torque curve and not to get a peaky one which is what many of us stumble at when fitting after market headers. Aim for drive ability before aiming for gains in bhp and torque.

Header-Exhaust Design Effects on Engine Power - Team Integra

HEADERDESIGN.COM - Unlock Your Engine's Potential

Bye and wear your seat belts.

[GTO]

My take on this: What some tuners sell / fit for you is absolute hogwash and nothing but a money making gimmick!! So called high-performance Spark plugs, badly installed / engineered exhausts, lightened flywheels, oversized pistons, mega-xxx size spoilers etc. dont amount to crap, if anything at all. Some of them will actually deteriorate the performance of your car due to the quality of product / install. Like Vip3r and nextlevel350z have rightly highlighted, most of the mods some "think" will improve performance dont actually do so.

It amuses me how many cars are out there loaded with junk, and yet boasts XXX BHP improvement figures. It does provide for a hearty laugh. Sure, there are some that really worked but they are far and few between. (Example : Rtechs Octavia before and after the Petes powerbox, Monkeys 7 second 0 - 100 RS, some engine swaps, forced induction jobs etc.). I recently got some sweet headers and basic mods on my Vtec (review coming up soon) and I dont expect a power increase. Alteast not significantly. All I wanted was improved driveability and good engine sound (Yup, am a sucker for good sound). With the basic mods, I got that.

Its disheartening to see nice, reliable, clean-running stock cars going in for silly mods and losing out on reliability, driveability and having issues crop up within a short while. My suggestion : If you really want to make your car go faster, save the money spent on junk add-ons and go to a racing school instead. It will not only make you faster, but also safer.

I think the industry is yet in its nascent stage, and the time is not too far away when we have pro-grade tuners with inhouse dynos, ready supply of after-market parts, great technical knowledge and a high quality of install / service. Think of them being as organised as some of the better authorised service stations.

P.S:I think its really about time that we get dynos in India.

[ananthkamath]

Originally Posted by GTO

most of the mods some "think" will improve performance dont actually do so.

I think the term you are looking for is "Mental Horsepower" or MHP.

[chetanhanda]

Originally Posted by GTO

and good engine sound (Yup, am a sucker for good sound).

same here.. engine growl..

[chetanhanda]

Originally Posted by GTO

My take on this: What some tuners sell / fit for you is absolute hogwash and nothing but a money making gimmick!! So called high-performance Spark plugs, badly installed / engineered exhausts, lightened flywheels, oversized pistons, mega-xxx size spoilers etc. dont amount to crap, if anything at all. Some of them will actually deteriorate the performance of your car due to the quality of product / install.

adding to the list ...hi performance wires,4 electrode plugs on stock cars,oversized injectors on stock cars running ECU with stock fuel maps - who can beat this ?
..this gives me an idea for another post.

[elf]

Originally Posted by ananthkamath

coming to cone filter installs. I dont understand why people (maybe i should say tuners) can be so lame as to put the filter directly in their engine bay where it sucks in hot air? Without any kind of heat shield.

If I do an install in my car, this is how I would do it:



The shiny box is a heat shield-cum-plenum chamber for the cone filter inside. The chamber is ducted to the bumper so only cold air goes in. And its insulated with fibreglass making it impossible to heat intake air. Making it a true "CAI".

So what you're saying is that the stock intake with a better replacement filter (say K&N) would do a better job than a K&N Universal?

Also, on the basis that an engine is nothing but a fancy air pump, one must presume that the engine can only suck in the air it needs, so one needs to get in as much air as possible. Restriction happens due to the fact that the air is being filtered, & hence, is a by-product of the filtration process, but the lowest level of restriction is desirable. Ideally, if we were running pure clean air, no filter would be necessary.

And as I understand it, bolting on a huuuuge air intake (like the K&N cylinder that I have currently) won't make any difference in performance, (apart from the performance gains due to the lower restriction material in the filter) and may even degrade it due to the hot air being sucked in.

Hence, the smartest thing to do would be to simply open your stock air-box, pull out your OEM filter, chuck in a K&N replacement (& VOILA! 25HP more... Heheh! Jes' screwin wid ya) & extend your intake pipe from the mouth of the OEM to somewhere in your fender or below your front bumper.

Please correct me if I'm wrong. And also read my post twice to understand it (I know I did).

[ananthkamath]

all i said is IF you want to put in a high-flow cone filter, then you must provide adequate shielding so intake temp does not increase beyond stock. At the minimum.

we cant generalize that a drop-in K&N could be better than a cone K&N. I think its more important, and no more technical, than to ensure that you have a supply of cold air in sufficient quantities. I would tend to incline towards the cone.

[elf]

Originally Posted by ananthkamath

... all i said is IF you want to put in a high-flow cone filter, then you must provide adequate shielding so intake temp does not increase beyond stock. At the minimum. ...

Agreed without doubt.

Originally Posted by ananthkamath

... we cant generalize that a drop-in K&N could be better than a cone K&N. I think its more important, and no more technical, than to ensure that you have a supply of cold air in sufficient quantities. I would tend to incline towards the cone.

Why would you incline towards the cone if the volume of air being sucked in is the same, irrespective of the design of the filter (cone or replacement)? All other factors remain the same - the filtration material in both is the same (K&N for example), it's only the design of the filter that's presumably sucking in more air. Which we all know is bull.

Originally Posted by elf

... an engine is nothing but a fancy air pump, one must presume that the engine can only suck in the air it needs, so one needs to get in as much air as possible. Restriction happens due to the fact that the air is being filtered, & hence, is a by-product of the filtration process, but the lowest level of restriction is desirable. Ideally, if we were running pure clean air, no filter would be necessary. ...

Any physicists / aerodynamicists / experts here care to comment?

[gigy]

I have put in a partsion between my ractive filter and engine bay, given two pipes from front of bumper to the filter, put in a digital temperature guage in front of steering with one sensor measuring cabin air temperature and other on air filter. i have not enclosed the filter completely because i wanted water to drain off rather than get sucked in. the two piping feed outside air into the chamber.
observed results:
before start both were reading same32*c.
after about running for 15 minutes on slow and steady powai traffic cabin was 31, filter 68.
took to eastern express highway cabin 31 and filter 32
wait at traffic signal 45 and was climbing before started again.
conclusion: give a cold air intake if you want best benefit of a after market filter. even if using stock filter remove the resonator box and feed in outside air, on long runs your engine will give consistent output.

[elf]

Appreciate your input on your findings gigy. The fact that heat shielding is absolutely necessary for a CAI is not an issue here. There's absolutely no argument on that front.

What I'm trying to understand is that would the same gains accrue if one uses a stock replacement filter from K&N in the airbox, or the Universal with a proper CAI.

[Desert fox]

Originally Posted by chetanhanda

Mods I know this may start a fight ..but I would like to disagree
I think Vip3r has created more confusion on this thread than contribution.

I would like to ask,before 2000,when cars were running on carb's,we were running on header's without a Ecu re-map-Why cant it be taken at that?

And rest since for one iam confused i would request you to place the real facts below the 'Quote's'.


P.S: Iam asking out of genuine curiosity and my post should not be mistaken for one filled with sarcasm!

[gigy]

My view is, for a stock engine a stock filter might be enough, a larger universal will be capable of giving more but the engine is not asking for it. There is a maximum quantity of air flowing at its highest rpm (torque), if stock replacement can give this, its enough. To know the volume of max airflow we will have to check the engine technicals and the filter max flow rate.
so for smaller level of modification i think it will be better to heat shield the filter box and put in a aftermarket filter, you get the same sound also without the resonator box as in a universal.