Adjusting Intrax 3-ways

[BertBert]

I'm sure the actual settings are a closely guarded secret, but what are the principles of adjusting the Intrax 3-ways?
Bert

[lanan]

Graham,.....As lifted from the Intrax site..!

A. Rebound
When the damper is in the car, first turn clockwise the clicker to the right, this will close the rebound fully. After this, start
opening click by click. We close the rebound fi rst to be sure all dampers are working from the same starting point. When
you close the rebound this will make the car move (come back) slower to normal position.

B. High speed compression
Turn anti clockwise until adjuster stop, this is the softest position, with max. 50 clicks. With high speed compression
hardness of the car can be controlled in a way you can assist spring rate and mak e the car stiffer.

C. Low speed compression
By turning clockwise low speed damping will increase (max. 18 clicks). With Low speed the roll in car can be controlled
and when in softer position (+/- 10 clicks) small bumps will be easier taken. (smoother drive)

Not sure if that was the type of info that you were after.
Graham

[BertBert]

Thanks Graham, that's a good start for the mechanics of what the three adjustments do.

I was wondering how then in practice you go about getting optimal settings for a given car/circuit/driver combination. It's probably the subject of a winter book! So happy for any reading matter recommendations.

I think I have a lay view of what happens, but want a more informed framework to use.

[Count Johnny]

Doesn't Carroll Smith deal with this in one of his inestimable tomes?

Probably Tune to Win, but if you haven't got them, Prepare to Win; Drive to Win; Engineer to Win; and Nuts, Bolts Fasteners and Plumbing (or something like that) are ideal winter reading and a great resource.

Edited by Count Johnny on Wednesday 2nd November 15:45

[jpivey]

Middle setting on all three adjustments and leave alone..

[BertBert]

jpivey said:

Middle setting on all three adjustments and leave alone..

It can't be that simple JP. There must be a magic setting worth 2-3 seconds a lap at Snett that I could get

[double d racing]

Of course there is another setting............right foot planted, eyes closed.....and only open your eyes as you hear the marshalls screaming.......

[DarcySmith]

Having owned a 4,a 6 and a 3 I would say that the 3 is the most difficult to set up.

It seems that the smaller cars you can jump in and just drive them quickly

The 3 caught me out several times,after a small adjustment,made the car unstable.

I had a long chat with one of the front running UK Cup drivers.

It seems that the quick guys run different spring rates to the standard factory set up

Rake is critical

Regards

Darcy

[radicalracer]

DarcySmith said:

Having owned a 4,a 6 and a 3 I would say that the 3 is the most difficult to set up.

It seems that the smaller cars you can jump in and just drive them quickly

The 3 caught me out several times,after a small adjustment,made the car unstable.

I had a long chat with one of the front running UK Cup drivers.

It seems that the quick guys run different spring rates to the standard factory set up

Rake is critical

Regards

Darcy

Did he tell you what spring rates? Softer or stiffer?

Any more info on the Rake comment?

Thanks!

[Coldaswell]

My understanding of rake is that it will effect the centre of pressure, or aerodynamic balance of the car as well as total downforce generated. Overall ride height at these sorts of heights will, I believe, have the same effects.

[Count Johnny]

Coldaswell said:

My understanding of rake is that it will effect the centre of pressure, or aerodynamic balance of the car as well as total downforce generated...

Correct, the right amount of rake effectively turns the underside of the car into a venturi, thus it can increase downforce and move the centre of pressure closer to the CG. The trick questions are, how much rake and how to control things when you brake - and potentially choke off the venturi and instantly lose that downforce - and arrange things to control how the the car generally changes its attitude to the ground in response to other factors like downforce and acceleration.

But with a big, flat bottomed, car like an SR3 rake is definitely of value so is worth pursuing. As an indication, our rake when the Speads is sitting on its main springs is 18mm although I believe 25mm or more is not unheard of.

Edited by Count Johnny on Monday 21st November 07:57

[tonto1]

When discussing the set up of my PR6, I was told by a very helpful 'Snr Chassis Engineer' at Radical to go with the following:

High speed – fully open
Low speed 15 clicks from fully open
Rebound – middle of range

This was using the standard spring rates and seems to have worked pretty well as a baseline!!

[radicalracer]

Thanks guys. I will look into this with my guys and see what they say. It has taken a bit to get the Intrax dialed in, but I think the results will be worth it in the end.

The hard part is to still get the car balanced as its natural tendency seems to be always be a bit pushy. So the compromise games continue...

G