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Old 04-26-2018, 10:30 PM   #26
pat244ti
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I agree with ditching the rear bar

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Originally Posted by brendon_ak View Post
I drove this car when I worked for the shop that built it. Head tilted about 65 degrees towards center to fit [Im 6'5]

I also sat in it a million times to hold the wheel for another tech while the centerlocks were torqued. Did lots of weird manuvering going in and out of the car to avoid my feet hitting the door panels. Helped pull the trans on 3 occasions. Glad they finally got it out of the shop
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Old 04-26-2018, 11:32 PM   #27
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Originally Posted by brendon_ak View Post
Here's some shots of the weekend
...
Drool.
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[Im 6'5]
Why, hello there.
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Old 05-01-2018, 05:45 AM   #28
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Originally Posted by EivlEvo View Post
A number of people run sans rear bar. This typically promotes understeer in all situations but it also prevents the turn exit spins (of both the tires AND the car lol)

It can be beneficial for a novice I suppose... that said, it can be beneficial to learn when to saw the wheel and balance the power at the rear end as well.

This said... the 25mm bar at the rear is no joke. I've spent a fair amount of time going sideways, dealing with various definitions of over-steer. Putting a 25/25 on my 245 and I almost spun (dangerously spun btw) my car with a 50-60mph transition that required throttle modulation. I would suggest putting the stock bar back on in lieu of the 25mm until you find a desirable corner balance (like corner weights) FR for the car.

2x Ford/Lotus Cortina , cars with front engine/RWD/ solid rear axel setup, much like a Volvo 240
notice how both Cortinas have their inner front wheel in the air.
This is caused by a big front s/bar and small/NO rear s/bar. This setup keeps the inner rear tire on the ground. That way there is no 1 tire wheelspin when exiting a corner. This picture was taken some time in the 1960's , these cars might not have had an expensive LSD fitted.

Just take some tools to the track and experiment with/without rear s/bar. It can be easily removed/installed provided you lift both rear wheels at the same time. (if you lift 1 side there will be springload on the s/bar)
It's fun and educational.

It is also possible to change front/rear balance with different tire pressures. But that's only for fine tuning.

found a similar pic of a 240 racecar.
[IMG][/IMG]

Last edited by Janspeed; 05-01-2018 at 06:01 AM..
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Old 05-02-2018, 12:50 PM   #29
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It's too bad you didn't come out to the Autocross. Marc Williams brought out his 142 track car and another friend of mine brought out his 242 autocross car. You would have been in good company. We actually had great weather, despite the forecast of rain.
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Old 05-02-2018, 02:16 PM   #30
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Originally Posted by Janspeed View Post
It is also possible to change front/rear balance with different tire pressures. But that's only for fine tuning.
IIRC:

Adding pressure to the front would have the effect of (within reason) reducing understeer. And vice / versa?
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Old 05-03-2018, 03:42 PM   #31
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Simply put, more front bar improves transitional (left-right-left) steering and more rear bar improves steady-state turning. This is relative to each other, of course. Most people (across the board, regardless of car) require much less rear bar than internet heroics would assume.
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Old 05-03-2018, 04:04 PM   #32
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Originally Posted by shoestring View Post
Simply put, more front bar improves transitional (left-right-left) steering and more rear bar improves steady-state turning. This is relative to each other, of course. Most people (across the board, regardless of car) require much less rear bar than internet heroics would assume.
You mean to tell me that I don't need a holset and coilovers to commute to work? *gasp*

WHAT BLASPHEMY IS THIS!!?!?!?!?

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Old 05-03-2018, 04:14 PM   #33
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You mean to tell me that I don't need a holset and coilovers to commute to work? *gasp*

WHAT BLASPHEMY IS THIS!!?!?!?!?

Heresy, I say! Eikers, poly bushings, Kerker 1 piece aluminum racing seats, side-draft Webers really aren't needed to go in a 30 mph commute? I've been mislead!!!!
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Old 05-04-2018, 05:33 AM   #34
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You mean to tell me that I don't need a holset and coilovers to commute to work? *gasp*

WHAT BLASPHEMY IS THIS!!?!?!?!?

You do if you want to do it TB stylr and win the commute. Front wheel drive cars are the opposite and need stiffening in the rear and softening the front.
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Old 05-07-2018, 06:42 PM   #35
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We have used pretty much every race pads for oem 240 brakes. We now use carbotech xp8 pads. If your car is in good shape, all you should need is pads, good fluid, and tires you don't mind ruining.
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Old 05-07-2018, 06:46 PM   #36
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Originally Posted by EivlEvo View Post
You mean to tell me that I don't need a holset and coilovers to commute to work? *gasp*

WHAT BLASPHEMY IS THIS!!?!?!?!?

I don’t want to live in that world.
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Old 05-07-2018, 06:52 PM   #37
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Originally Posted by LC4CARL View Post
IIRC:

Adding pressure to the front would have the effect of (within reason) reducing understeer. And vice / versa?
Really, tuning tire pressures is in excercise in add and subtracting tire “grip”

You change the contact patch, and spring rates to some extent when you start with tire pressures. As well as ride height and corner weight as well.

Chassis tuning is a game of give and take, ideally you would use 100% grip all the time, but because we expect cars to handle specific ways, (oversteer, under steer) we spend time changing the available grip to suit our needs.

I have been to a number of chassis setup schools, for dirt oval and road, read tons of books, have some class wins and a second overall autocross championship and I still only pretend to know anything about it.
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