quafie gears

[metro1]

hi has anyone got any advice on picking a set of gear ratios to use for drag racing, the box im using is a ford type 9. Im planning on putting between 220hp and up to a max of about 280hp i know im going to fit a quafie gear set the car will weigh in at about 650kg and wont be used on the road i have a budget of about £1200
has anyone used firstmotion transmsions or road and race transmisions in seven oaks any opinions or recomendations would be apreciated

[Nick1point9]

In my experience, you set your gear ratios based on your torque/power curves so that you get the right rev drop to stay in the power band, and then set your final drive based on the expected speed range etc.

[stevieturbo]

Lots of variables.

But generally with a manual most people try to finish the quarter using only 4 gears.

Unless you've a sequential box where you can shift without lifting off. Then you could maybe expand that to 5 or more.

But a lot will depend on power, power band available. It's a bit of trial and error really.

[nedge2k]

any of these help?

http://www.hotrodpitstop.com/tool.php

[Classic Grad 98]

I've used Road & Race a number of times including work on my type 9. Highly recommended.

[stevieturbo]

Weslake-Monza said:

I'd check what the max bhp/torque rating is of a type 9 as your projected power outputs appear to be close to its limits.

If he only weighs 650kg, then that should add a little safety

[metro1]

was told it should be safe by one builder providing the power is linear and aparently thr quafie gears should be able to handle it and the non agresive downshifts will help although quafie's website says diffrent owh if its any help i will be upping the rev limit to 8500rpm

Edited by metro1 on Saturday 11th February 23:40

[rev-erend]

There is a useful gear calculator here :

http://www.gearboxman.co.uk/info.html

[Incorrigible]

Type 9 4th gear is straight through, so given your anticipated final speed that will give you your diff ratio. Then get your other gears as said before from the torque curve

There are 2 basic types of type 9. The later stronger one (often called the V6 box) had an uprated layshaft support bearing. Quaife do gearsets to fit either IIRC

And Phil at R&R is excellent