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JeremyC
2009.11.16, 01:12 PM
After a couple months of racing Z's it seems like it is harder to get grip at the rear of the car than at the front. In light of this, you always want to maximize the grip at the rear, and adjust the front end to make sure your car is balanced to taste.

I'm just thinking outloud here and I could very easily have this all backwards, but I think the way to setup your car is to start with the grippiest rear tires and a soft H-plate. Run the car for a few laps, tune the ball diff for maximum grip. At this point we know that the rear of the car has about as much grip as it can have. Since the rear is harder to get grip on, and it is maximized, you know you want to tune the front.

If it is understeering it means that the rear has plenty of grip and you need to bring grip in the front up. Can you go to a front softer tire? Can you soften the springs a little? Notice we don't want to change the H-plate as that will bring front grip up at the expense of rear grip.. Keep increasing front grip until you don't think you can do it any more, at that point, if you are still understeering more than you want, stiffen the H-plate.

If the car is oversteering your front is grabbing too much. First ask yourself is the car is setup for maximum rear traction, if not, fix it. If it is; Ratchet down the front; use harder tires, harder springs, less camber.

-Jer

PS: I have no idea if this post is correct, but it is how I am currently thinking about setup and thought I'd put it out there for people to comment on.

z3zinho
2009.11.16, 01:37 PM
Overall, on 'normal' tracks your train of thought is similar to mine. One litle thing you should notice, on really high grip tracks (like the crazy grip you guys get on some tracks in the US) there is a point were too much grip makes the car slow because of 'all around scrub'. Don't know how to explain it better but probably some of the guys that are used to high grip tracks can give you a better insight into this...

Continuing on your setup idea... The H plate controls longitudinal, and transversal stiffness. So going with the softest H plate as a starting point isn't probably a good idea. There is an ideal range as far as 'suspension hardness' if you go to soft the increase in roll in a corner will be detrimental to overall grip as you are putting to much load on the outside tyres. That's why why real sports car have stiffer suspension compared to regular cars.

So for example, in a fast track with long sweepers you will probably want to run a harder H plate, for a slower track with a lot of hairpins a softer H plate should do the job better. There is always going to be a tradeoff between the fast corners and the slow ones.

Otherwise, the whole concept of trying to get the most grip out of the rear, and then tune in some steering is usually what I aim for when tuning my car for a different track. You will eventually get to a point when you may have to much steering (imagine AWD traction rolling) but still you need the car to rotate more, then you can start thinking about taking out some rear grip to balance the car better.

Hope this makes any sense to you...

JeremyC
2009.11.16, 02:18 PM
Hope this makes any sense to you...

Alberto,

It does make a lot of sense, and I'm glad to hear that my train of thought isn't totally off base.

To be honest I don't really understand the interplay of the H-plate and DDS while turning and twisting the chassis/pod. Which is why I didn't even mention it in my first post, and also why I assume the softest plates give the best rear traction.

If stiffening the h-plate to increase transversal stiffness can result in a more desirable weight distribution I also assume that using a thicker oil on the DDS would have a similar effect for turn in, and opposite for turn out.

I think a lightbulb just went on for me..

If I put a heavier oil on the DDS: during turn in; it is similar to putting a harder plate on, but turn out it would act more like a softer h-plate. This is because the movement is resisted in both directions. So for turn in the plate is flexing, but it has some more resistance, so the pod is slightly harder to twist, but turn out the DDS is resisting the H-plate straightening, which is kind of like an even softer plate since the DDS is holding it back from flattening. ... My mind just got blown.

So, that would mean that a heavier oil would cause more turn in and less turn out.. Or more oversteer at the start of a turn, and more understeer at the end.

The DDS springs have to affect it in a similar way, but I can't think about that right now...

CristianTabush
2009.11.16, 05:08 PM
Thicker oil increases dampening effect in the rear. This makes the rear react slower and makes the car more forgiving, but reduces rear grip. Thicker DPS oil is good for high grip tracks where you want the car to transfer weight more smoothly from side to side.

There is no real "right way" to achieve a desired balance, as there are so many elements that go into play. I would say that you F/R tire combination is about 75% of your set-up, the sum of all the rest of the adjustments makes up about 25%.

The way I attack a race and set-up Reflex's cars is:
1.Find the right rear tire
2.Find the right front tire
3.Find the right front spring (use the springs to control straight-line stability, turn in is adjusted with different compound tires)
4.Find the right h-plate (go harder if I need a car that rotates quicker, opposite if the track is sweeping)
5.Find the right lube for DPS (300wt-1000wt is the usual range)
6.Find the right lube for front end (if I happen to be using some the given weekend)

If I still can't get the car to be right, I will switch bodies/wheelbases and start on #1 again...

LogicBytes
2009.11.16, 11:21 PM
Thicker oil increases dampening effect in the rear. This makes the rear react slower and makes the car more forgiving, but reduces rear grip. Thicker DPS oil is good for high grip tracks where you want the car to transfer weight more smoothly from side to side.

There is no real "right way" to achieve a desired balance, as there are so many elements that go into play. I would say that you F/R tire combination is about 75% of your set-up, the sum of all the rest of the adjustments makes up about 25%.

The way I attack a race and set-up Reflex's cars is:
1.Find the right rear tire
2.Find the right front tire
3.Find the right front spring (use the springs to control straight-line stability, turn in is adjusted with different compound tires)
4.Find the right h-plate (go harder if I need a car that rotates quicker, opposite if the track is sweeping)
5.Find the right lube for DPS (300wt-1000wt is the usual range)
6.Find the right lube for front end (if I happen to be using some the given weekend)

If I still can't get the car to be right, I will switch bodies/wheelbases and start on #1 again...

I'm fairly new to Mini-Z and my driving has been improving I feel one of the things that is holding me back is having the proper setup and learning how to change my setup when the track layout changes. Iv'e been trying to soak in as much as I can on it. I agree that finding the correct tire combination is probably one of the most important things; when you say find the right rear tire first how are you determining this? Also when you say use the front springs to control straight-line stability can you explain this further. I didn't see you mention anything about tuning the springs on the damper plate does this really not have that much effect on the handling characteristics of the car or is it minimal and you get the most significant tuning by changing the weight of the lube on the damper plates. Sorry for asking so many questions.