This article applies to Autograss Stock Hatch 1600 cars (See my other guides for best way to start building one). Other racing classes are completely different. Also, it's a guide for beginners to get ideas from and test boundaries, not a definitive guide - experimentation is key and every car, EVERY car, is different.

--> Reminder: We aren't allowed to fit uprated springs (lol), change suspension mounts or fit lsd/locked diffs so to all those handling experts out there who are thinking "What ARE you on about?" - There is method to my madness!

The key suspension setup technique I've used in my Stockhatches has been to use the REAR suspension to help the FRONT wheels. With a few extra tricks.

Stiff front suspension will make the front driving wheels skip over bumps rather than follow them - bad. To make your drive wheels follow bumps and keep drive-contact with the dirt, they must have relatively SOFT suspension. Every time your drive wheels skip on a bump, you lose traction - even if it's only the inside wheel that leaves the ground, you still lose drive to the other wheel because of the differential.

Stiff rear suspension makes that rear end do all the anti-body-roll work and widening the track gives it more leverage. That leaves the front end to do its job of pulling mud backwards!


Imagine a FWD car in a turn, in these 2 situations:

• Very wide front track with narrow rear
• Very wide rear track with narrow front

With the same amount of body roll, the inside wheel on the WIDE end lifts off the ground to some extent - More than the NARROW end does. If you can make sure the wheel that tends to lift most is NOT a drive wheel, you'll be better of than someone who doesn't get this idea. (If you have a limited slip diff things are different, But we don't do diffs in Stock-Hatch).

So these things help front-wheel-drive traction:

• Narrow front end track
  
• Wide rear end (Use spacers)
• Soft front suspension
• Hard rear suspension
• Front tyres as grippy as possible
• Rear tyres much less grippy
• Rear anti-roll bar
• Also, nose-down tends to be best for FWD straight-line traction
  

REMEMBER:

1.  You are trying to induce oversteer (Or at least kill all the understeer you possibly can)
   
2.  Drive wheel grip is King
3.  'Predictable' handling isn't your TOP priority in Stock Hatch 1600
4.  Predictability on the way OUT of bends will help a lot
5.  Don't steer too much! Panic (Counter-)steering upsets a cars floooow

Many experienced racers, especially those working with tarmac will tell you that predictable handling wins over extreme grip - balance is best... They are right! But in Autograss, we have the opportunity to tune our handling for only 2 (Or more correctly, 4) bends. We don't need to have a car that is a 'Jack of all trades' as far as cornering goes. Having said that, most Autograss local series' are raced on 3 different tracks around your area (My local club do the whole season on one, which is great for tuning on that track alone) but you're still only tuning your handling for 3 tracks. If you travel a lot, you'll just have to do what you can and learn from those different tracks.

A few extra tricks (Mostly questionable, but what isn't?):

 - Put a knobbly tyre on the right-hand rear wheel. On exiting a bend, when the car 'Flicks-back' towards a left-hand turn, that knobbly tyre will dig in much more than the bald tyre on the left-side and help stop a disastrous left-hander into the wall. Lol, been there. That wheel will always do the least work on entering a bend (Because it lifts a lot) so won't do much against the oversteer you are trying to induce. However, it can 'calm' that oversteer if you let it hang out of the arch a bit using softer shock settings.

 - Softer shock on inside rear - re the last point - 1) On exiting a bend, the softer shock will cushion the blow as that wheel/tyre gets back in contact with the dirt. A bit more grip here will help against 'Disastrous flick back' 2) on entering a bend, if you have absolutely manic, uncontrollable oversteer, you can calm it a bit by allowing this corner to have a bit of contact with dirt - dragging that corner of the car DOWN (Helping your all-important inside drive wheel, believe it or not). Now I know I said "Hard rear suspension" but just try it and see - GREAT tuning-adjustment potential on this point alone.

 - Remove your front anti-roll bar. We're not allowed to use (Nearly) any uprated parts but you can still remove some! If it doesn't work, put it back on, you've lost nothing except time taken. Or use a knackered old one on the front and a shiny brand new one on the rear.

 - When your outside-front tyre - the working tyre - has lost its outside edge, swap the front wheels over. A tyre's rotational direction counts for little compared to a good outside edge. Obvious but worth pointing out.

 - Re Tyre pressures: Get someone to look closely at how your outside-front drive-tyre curls under during cornering. If it doesn't curl at all, lower the pressure. If it's driving on the sidewall, raise pressure. You have to get the part of the tyre that's designed to WORK in contact with mud and without evidence, you can't set drive-wheel tyre pressures sensibly. Low profiles help reduce curl-under but can make wheels hit the dirt and tyres de-rim.

 - Re Camber: More negative camber on outside drive wheel makes curl-under work for you - allowing lower pressures! positive works for you on the other side. Go Mad on camber and see if it works! And if people quote the rules about 'Excessive camber' or tell you it's no good for straight lines - let them suck your dust! Straight lines are great but DAMN - The track's OVAL!



The End