Tune & OTR

[whiskeytango]

Think about it like gears on a pushbike. Starting off on the biggest cog was the hardest so you'd always try start on the smallest. Then you have the gear box to to the rest.

 

[vr304]

Means you will accelerate faster with a lower top speed, say for example with your standard diff gears you can do 70kmh in gear you add some shorter diff gears now you only get 60kmh in 1st but you get there a lot quicker... it doesn’t add any horsepower but makes the car a lot more lively and feels like you’ve gained power due to the quicker acceleration and if you don’t go silly with the ratio choice u can actually get better fuel economy during normal driving due to the engine having less load on it to get up to speed

 

[Theprojectcar]

No they don't increase power or torque.

What changing the ratios does is change how the power and torque is delivered through the wheels.

They can increase and decrease acceleration from a standing start, while accelerating in gear and the top speed.

If for example you have a car with a stock from factory diff ratio of 3.45:1 and change it to a lower ratio 3.70:1 your car will accelerate faster, your top speed will decrease and you may use more fuel.

It's a great way to make your car go faster.




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Thanks for that. Really helped.

 

[Theprojectcar]

Think about it like gears on a pushbike. Starting off on the biggest cog was the hardest so you'd always try start on the smallest. Then you have the gear box to to the rest.

Thanks for the reply, that’s a good way to put it. I understand now. Will have a look.

 

[panhead]

Thanks for the reply, that’s a good way to put it. I understand now. Will have a look.

Auto transmissions and manual gear boxes also play a part as they are geared differently so unless your going on an all out assault to achieve the fastest time possible down a track, your choice of diff gears to allow good daily drive manners will depend on your type of transmission.

There are plenty of members here that can give good advice on the right ratio to suit your needs.




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[Theprojectcar]

https://www.facebook.com/video.php?v=258464935265844

Here is my babe :’)

 

[HB.SSVR]

In regards to factors that influende dyno figures. Would tyres with minimal tread (close to bald) give a higher reading?

 

[07GTS]

In regards to factors that influende dyno figures. Would tyres with minimal tread (close to bald) give a higher reading?

ive got some almost skun ones so ill be buying some cheap tyres just to kill on the dyno, problem is the lower hp cars need to be strapped down less as if u go too tight u will lower the reading because of the added effort against the force on the rollers, on opposite the higher hp u need to strap them down hard to stop spinning on the rollers, so your almost bald tyres will prob spin more on the rollers so will have to strap it down harder to help and possibly loose some power

 

[HB.SSVR]

That does make sense but somehow I got the opposite effect. My tuner told me that my readings are slightly higher as my wheels were needing to be changed. Which in effect the tyres spin more on the rollers showing a higher kw. I did also think it made higher than expected power.

 

[07GTS]

if traction wasnt an issue then what ever the difference in rolling diameter from brand new to bald tyres would affect it like a slightly higher diff ratio, minimal but enough to change it same as what tyre pressure does with rolling diameter on the dyno