[Ford Rocam]

i have done direct porting to it
i have also got the heads recently polished

Can you elaborate more on that "direct porting" have heard for the first time & Polishing where you have got it done

i also use petrol with high performance additives

.
which fuel do you use & what additives ?

i use honda accord oil in my car
the showroom guy said its different from city oil

What Viscocity?

i get so much power coz my k&n has a directr connection to the engine i.e i have put a original k&n pipe along with the filter

Can you post the pic for same?& pic of your engine Bay. is your ECM Stock or are you using Apexi VAFC

Regards

[Boom Shiva]

Originally Posted by honda_dude

i didna say i havent tampered with the electricals

Hey could you also specify what all you've done with the electricals?

[Fuelled]

@shantanu-
Boy i had no idea how speed was calculated. Thanx
But i'm stil a little sceptical.
I mean everywhere else i've read that if you have a new tire that is either bigger or smaller in circumference than ur OD, then ur speedo reading goes for a toss.

[Shan2nu]

I mean everywhere else i've read that if you have a new tire that is either bigger or smaller in circumference than ur OD, then ur speedo reading goes for a toss.

Yup thats true, using a smaller or bigger tyre will increase speedo error wrt vehicle speed and not tacho readings.

For EG: If i fit the Vtec with 145/60 R13 tyres. It's circumference would be 145 * 0.6 / 25.4 + 6.5 * 2 * 3.14 = 62.33 inches.

So at 7100rpm in 2nd the car would be doing 87.06 kmph (-2%). But, your speedo would still be reading the factory caliberated speed at this point (which is 98kmph in my car).

So, your speedo error would have increased by 11.3 %. Meaning that your car is showing 98 when you're actually doing 87.

When upsizing, always go for a tyre size that will increase circumference by a little (withing 3% though) This will reduce your speedo error by a certain %.

Shan2nu

PS : Mods, i think you can move all the speedo error posts onto a new thread titled "Speedo error, are you aware of it?"

Shan2nu

[diven_b]

hey shan2nu
say if i am using 195/65/15 rite now........and i upgrade to 215/45/17....what (%) will the error be like.?

[Shan2nu]

195/65 R15 has a circumference of 78.43 inches.

215/45 R17 would come to 77.30.

So your speedo would be over reading by 1.5% (Which is ok i guess).

You could also go in for 215/50 R17, which will reduce speedo error by 1.9%.

45 profile is a bit too low for Indian conditions.

Shan2nu

[diven_b]

thanks..that solved a few doubts

[Fuelled]

Hey thanx shantanu for clearing the confusion. I didnt kno it was like that

And Diven B use this link to calculate ur tire error(its already been posted before by rtech, but jst for a shortcut)
http://www.miata.net/garage/tirecalc.html
and the thread link
http://www.team-bhp.com/forum/tyre-a...alculator.html

[honda_dude]

thanks evry one for taking so much interest in my post
actually i have 205 /40 r17 on my car
and i dont know if there is any error in my speedo but the tacho actually shows around 120-123 when i rev it in the second gear
also sajid has done sumthing to my rpm setting due to which the engine feels over revved all the time

and so when i do around 100-120 my rpm reaches upto 7500. is this the reason my car's showing such a high speed or is there some error with the speedo

[honda_dude]

i was wondering to change some parts to increase my performance
could u'll suggest me some good picks

1) msd ignition
2)pressure regulator
3) turbo ignition
4) turbo charger

also can sumone tell me is turbo charger and intercooler the same

as my budget is low i was planning to go for msd and pressure regulator
are these parts gonna help?

[viper]

Hey,

A fuel pressure regulator and MSD ignition will help. The combined cost should be in the vicinity of approx 30-40k depending on the MSD parts you fit.

A turbo setup will be out of your budget.(1lac upwards)

Viper