Dangerous And Scary !

[chris brown 165]

There are different dummy struts (the tube that fits into where the mc strut goes normally and has the taper hole in the top for the joint fits) some stick out of the upright by only 5 or 6mm or so ( original RHE supplied) but better ones are 50mm or so.

[Bob Tucker 863]

Correct Chris...as always!

some conversions (eg RS Jigtec) fit the wishbone brackets to the top & bottom chassis rails,

RHE fitted u shaped tubes above the bottom tube & below the top one.

Gave an overall difference of about 4", hence longer dummy struts for Jigtec.

The ideal setup has both the wishbones parallel to the ground at normal ride height viewed from the front.

[Ian Marr 45]

Trying to measure my set up and my best estimate of caster is just over 1 degree offside and nearly 2.5 degrees near side. I am assuming mis-matched caster is not a good thing? Trouble is I will struggle to get the 1 degree increased, but may be able to decrease the 2.5.

 

Car is standard 2b with rh wishbones, plus the newer elongated dummy struts.

 

Ride height looks okay (car looks right from side), but floor to sump is 3" and diff is way up (9"?)

[old_timbo 20]

That's about right for a standard 2b, and is the reason for poor self centring and feedback through the steering. You really need 5 degrees of caster minimum. I ended up at 7 degrees and to achieve this made custom top wishbones.

Have you managed to get some static negative camber? Using 205/55 R15 tyres I find 0.75 degrees works well. I found the standard top wishbones were too long with longer struts so another problem new wishbones sorted.

[Ian Marr 45]

I can get a little negative camber when stationary/wheels straight on both sides. Going to see if I can squeeze a bit more caster :-/

 

[Snapperpaul 441]

Blue caster change on Monocoque can be done by moving spacer washer on top wishbone pivot whist leaving bottom track control at 90 degs to centreline

[Dean Roberts 237]

I run .25 toe in, out will cause instabilty,if camber is adjustable -1 degree is a good start. tyre pressures are critical 20 max.

 

Really....I should have 20 psi in my tyres

 

I have been doing test runs in my 2B with 195/65 14 tyres with approx. 30psi

Would this explain why the car feels so light on the front end and a little unstable at high speed 70mph?

[Ian & Carole 1,061]

Dino

 

I run 18 front and 20 rear, I am a bit lighter than some as my engine weighs the same as a loaf of bread.

[mower man 545]

Really....I should have 20 psi in my tyres

 

I have been doing test runs in my 2B with 195/65 14 tyres with approx. 30psi

Would this explain why the car feels so light on the front end and a little unstable at high speed 70mph?

It certainly will !!!!! in the words of various people in the past "drop em blossom!!!" 18 is very well used , I have been down to 14 but worked back and finished up at 18 mower man

[david_l_perry 100]

I run 18 front 20 rear as well....I did try it a little lower (16 front 18 rear) but find this works well for me...

[Snapperpaul 441]

Dino we use toe out and 30psi only for IVA to help centering

I did continue to run a little toe out but with 18psi and found no issue except understeer

Corrected to fraction toe in all OK

I recon 30psi in a car half the weight of the donor will cause the handling issue as your probably only using the centre part of the tyre

[Dean Roberts 237]

It certainly will !!!!! in the words of various people in the past "drop em blossom!!!" 18 is very well used , I have been down to 14 but worked back and finished up at 18 mower man

 

Cheers Guys.......As Mr Mower Man informs us "drop em blossom!!!" and I will see how it feels after trying 18 and 20 (oooeerr missus).

[Longboarder 642]

I did a Barkstone Heath sprint morning with tyres at 30 psi all round. Had the wrong glasses and couldn't read the tyre gauge. It was the most fun I've had in ages. Drifting and oversteer all morning. Slow but great fun. I found someone with working eyes at lunchtime to set pressures to 18 all round. Speed and handling restored for the afternoon but I wasn't Ari Vatanen any more.

 

Nigel

Edited April 23, 2014 by Longboarder

[Bob Tucker 863]

Anyone else remember Rizla's adventures at Barkstone.....

He had a light car (MNR) a well spec'd engine (cant remember what) loads of driving experience,

* endless enthusiasm....but the car just wouldnt drive right...

At the end of the day we found he had used standard Sierra pressures of about 35PSI.

At 20 PSI the car was brilliant.

[Drewsus 2]

I remember it well. So much potential and beaten on "style" points by an xr2!