Mud-club

Chat & Social => The Bar - General Chat => Topic started by: disco-v8 on September 12, 2007, 10:23:14

Title: engine tuning
Post by: disco-v8 on September 12, 2007, 10:23:14
ok first of this is not a crapy question asking how do i get more power out of my engine (ive alreadydone that  :P )......

..... its just a question about something  that doesnt realy make sence to me????

god nos how im going to put this but ill try my best.... take for instance i have a 3.9 V8 and the only thing that gives you all the power is basicaly the fuel and air that burns.  well to get the proper burn rate that gives more bank for your buck is 14.7 bits of air to 1 bit of fuel, and with my 3.9 having lambdas its trys to keep this at a constant (yes i know they switch for low to high, and get a average reading) so basicaly heres wot i dont understand:-

1 if the fuel pressure is high, more fuel is added, then the mixer wont be 14.7:1 so the ecu will try to adjust the injector puls width

2 if the pulse width of the injector is changed so its open for longer, then more fuel is added and yet again and the ECU will try and correct it

the only way i can see that you can get more power BY FUELING is to get  more air in the system then more fuel can be added, and the only way i can see this hapening is by a super charger or turbo charger, so how the hell do all these CHIP companies gain more power out of a N/A engine.....

i just cant get my head around it  :?
Title: engine tuning
Post by: jjsaul on September 12, 2007, 10:26:20
as far as i can see it, the OEM fuel map when your car comes from the manufacturer is a balance between performance and emissions.
if you put more fuel and more air in, i guess there is more emissions.

the bit i don't get is when the chip is fitted to adjust the fuel map etc, how it can give more power and allegedly improve fuel economy... :?:
Title: engine tuning
Post by: disco-v8 on September 12, 2007, 10:41:36
Quote from: "jjsaul"
as far as i can see it, the OEM fuel map when your car comes from the manufacturer is a balance between performance and emissions.
if you put more fuel and more air in, i guess there is more emissions.

the bit i don't get is when the chip is fitted to adjust the fuel map etc, how it can give more power and allegedly improve fuel economy... :?:



as rule of thumb you cant get more power and better MPG but basicaly imagine your engine is over fueled then you wasting more fuel plus the perfect fuel ratio of 14.7:1 isnt been matched so your losing power aswell, so with a decent MAP this can be obtained..... vus more power and more MPG :idea:

but like you said if you put more fuel and air in, but how do you get more air in?????? as it been a N/A engine the only way it gets in is by the piston going down, so every rotation sucks the same amout of air in as the last under full load ( butter fly open ) so like i said how is it possible to get more power?????
Title: engine tuning
Post by: lambert on September 12, 2007, 11:38:00
They are run in conjunction with free flow air filters and or less restrictive inlet tracts thus more air is available.
Title: engine tuning
Post by: rollazuki on September 12, 2007, 11:51:18
You are not gonna be running at stoichiometric (14.7:1) for a kick off.

You are gonna be running richer to safeguard pistons and valves, hence the emissions.

You could get more power by finer tuning, but having the means to do this is unusual.

You could increase airflow thru thr motor with higher lift and overlap cams. These will help, but by increasing overlap, you waste more fuel, so increasing emissions etc.

You could increase compression, but be carefull running it on pump petrol if you go too high.

Easiest way to cram more air in is to turbo or supercharge, but these ways arent cheap.

Simple way.....Nitrous kit, adds its own fuel(petrol) and Oxygen(nitrous) and gives a lovely hike in power. Cheap too.
Title: engine tuning
Post by: Xtremeteam on September 12, 2007, 18:54:41
fitting a chip to say a V8 allows us to advance or retard the timing  & also add or remove fuel to allow us to give power V economy,

basically if you pull fuel out then it makes it run slightly leaner which gives you your power,

altering the timing also has an effect on how much power it makes, :lol:

ill try & write a better response when im at work tommorow as this is what we do
SimplePortal 2.3.5 © 2008-2012, SimplePortal