[DRC]

Experts,
I get to see a lot of mod suggestions, and claims of "..increases xx bhp".
What I understand is unless tested on a dyno, you dont have a clue what a perticular mod actually has done good..

Now, for a perticular mod, how do you guys decide it will increase so many bhps, Is there a math, claims by mod equipment manufacturers, experinece, test results from a dyno.. How do you arrive at those figures, even approximately..

Take for example,,,
1. k&n filter
2. free flow,
3. irrdium spark plugs,
4. performance HT cables (?) Still Dunno how they work.
5. chips.

Its great if you can attribute some numbers/percentages against them and say why/how..

Thanks in advanc for the enlightenment

[Psycho]

Without access to a true road / engine dyno's the best that most can do out here are using the following methods:

1) Setup the engine manually based on experience
2) Use tools like gtech
3) calculate average bhp figures based on 1/8, 1/4 mile runs.

Some of us also have access to other calculations that are based on airflow and generic data on Turbo Calculations. Agree the methods are rudimentatry but still manage to give the average figures that we need on improvement.

However the examples that you have given excepting for the chipping option the rest of them will not give you very great performance gains.

Easiest method to understand if a part is going to increase visible performance is by checking if the part will help in any of the following:

1) Increased breating by an engine (CFM) by using filters, porting valve grinding, free flow, turbo's etc.
2) Compensating by increasing fuel supply (chips play an important role in point 1 and 2) by rejetting/replacing carbs, larger injectors, better fuel rails, upgraded fuel pumps (this usually requires better ignition to burn the fuel.
3) Lighting engine components like pulley's, crank, pistons etc...
4) Reducing drivetrain losses (performance clutches, lighter wheels with better tyres etc.)
5) Gear ratio's
6) Handling and braking upgrades

Hope that this clears some of your doubts.

[DRC]

Thanks Psycho,
I get the right direction to think.. May not be the answers,,,

I agree, that tyres, transnission, breakes, etc.. will improve the performance and handling,
Actually I was thinking more in the direction of therotical power than on a purpose of modifying the car..

Now, For example, (just to break the very auto perspective) a generator engine generating 100bhp. Naturally aspirated, like stock as in any automobile, need to be modified. And say, K&N has designed a filter (only for example!!) , would they have edsigned it to increase some specific percentage of power. Then, If so, is it possible to design with varying such figures..
So is the case with other mods I mentioned earlier..

[Psycho]

Originally Posted by DRC

Now, For example, (just to break the very auto perspective) a generator engine generating 100bhp. Naturally aspirated, like stock as in any automobile, need to be modified. And say, K&N has designed a filter (only for example!!) , would they have edsigned it to increase some specific percentage of power. Then, If so, is it possible to design with varying such figures..

The answer is yes it can be designed according to need. As for the K&N example the main aim for the manufacturers is not the HP gain but the airflow increase that they can get over the stock filters and a no replacement need. As for arguments sake you could get away by putting in a larger airfilter with a greater surface area to get similar performance, however K&N takes it in the other direction by trying to increase airflow in the least surface area possible.

Not all aftermarket parts are designed with power as the end result, they are designed to be the best performers in the given area they are used in.

A combination of such products will definitely help you achieve more power if used correctly, and if you still want more then you explore routes of altering the engine itself for more power.

This is true for any engine type and not necessarily automobile engines.

[GTO]

This post by DRC really brings 2 things to light:

1. The surprising lack of a public dyno where modders can go and check if a particular modification has actually had an effect or not. Could be invaluable with heavier engine customisations.

2. That there are just too many car guys who throw crap about the BHP their car makes. I always...always...take quoted BHP figures with a pinch of salt.

GTO

[Psycho]

Welcome to the real world is all I can say... Anyway without legal tracks and the publics need for true power that is what we are going to see for a long time to come. However please do keep in mind the costs associated for setting up the tracks and the dyno's are really quite high and we dont see any govt support towards motorsports...

It is easy to say that it is all crap but it really isnt easy to prove it otherwise ...

[GTO]

It is easy to say that it is all crap but it really isnt easy to prove it otherwise ...

When I hear talk about 300 bhp Citys running a 1.5 liter engine with just a turbo and misc. systems, it would sound dubious to anyone!

And its not necessary for a garage to buy its own exclusive dynos. I have seen plentiful of dynos which you could rent by the hour around the world. With such a huge "fast and the furious" culture growth in the last 3 years, its surprising to see the lack of one single dyno.

GTO

[DRC]

Now for example, a turbonator Joke, If a genuine guy had made it and had to claim the bhp figures how would he do it..
Hope I am not asking for too technical details that I too can't understand..

[Mpower]

Originally Posted by GTO

When I hear talk about 300 bhp Citys running a 1.5 liter engine with just a turbo and misc. systems, it would sound dubious to anyone!

I think it was a couple years ago, some mustang club owners got together and sued Ford Motor Co for advertising a BHP figure that was higher than actual (Mustang Cobra model). They
gathered about 15 cars, put them on a chassis dyno and proved beyond doubt that it was off by about 20 hp. Ford came back and agreed to this and
apologized stating that a last minute change in the exhuast had caused a drop in hp. Similar thing happened with Miata.

[v1p3r]

Ford and Hyundai both. Dunno about Ford, but seems Hyundai still does it.

[mahi0375]

Chennai is getting a new Dyno soon...

[Psycho]

Originally Posted by DRC

Now for example, a turbonator Joke, If a genuine guy had made it and had to claim the bhp figures how would he do it..
Hope I am not asking for too technical details that I too can't understand..

The easiest buy in for any potential buyer would be a overlaid torque/bhp chart from either an engine / chassis dyno with and without the turbonator. Any trial with the help of mathematical calcs would not register with customers and they would fail to understand that.

As far as I know there is one chassis dyno that is available to the public at Coimbatore at the Jaya engine plant.(havent seen it personally yet) Looks like I might have to make a trip there...

As for bhp figures from manufacturers ??? "We Need A Chassis Dyno"

[turboindia]

Originally Posted by mahi0375

Chennai is getting a new Dyno soon...

I too heard this but am not too sure