ekt

iTrader: (4)

http://www.exotekracing.com/dex210-r...ad-conversion/

Dino_D

From the testing, if you use the LRC or -2mm rear sus holder, don't run any spacers on the inner camber link. If you use the HRC or stock rear sus holder, you will need to run 2mm spacers on the inner camber link. Remember that the HRC conversion changes the roll centers of the car, allowing the LRC to act more like a HRC. I find that the HRC works better when the track surface has lower grip. As the grip comes up, you will need to add back spacers to put it back to the stock roll center that comes with the kit. The difference of moving the shock tower and bulkhead to the front of the arms, is that the shock tower is attached to the chassis instead of to the gearbox, which allows the back end of the car to flex a bit more and give you a bit more traction and stability.

If you want more roll, add more shims. Remove shims for less roll.

fredswain

iTrader: (1)

This will probably confuse everyone so let's see who can figure out why this is the case. Running the LRC block will give you less antisquat than the HRC block will, even with the same amount of rear kick. Remember, changing only one thing rarely affects only one thing.

Dino_D

Before assuming... Let me clarify..... I am not just changing the rear block..
Cause if you change just the rear block, then you are increasing antisquat by a lot.

Let's say using HRC that you were running the stock 1.5 antisquat, then when using the LRC -2mm you should be using the 0/3 rear front sus holder. But I think when using the 0/3 actually give you around 1.8 antisquat in LRC mode.

If you left the 1.5 block and went to LRC in the rear, then you have in affect close to 3 degrees, which changes another parameter..

Using the Exotek blocks rear front sus holder, you can shim the front up or down with 0.5mm, 1mm and 1.5mm spacers to correspond with using either the HRC or LRC blocks.

Alternatively you can use the TD adjustable rear front sus holders which uses inserts, however the settings on these are a little different than the stock antisquat configurations.

All I was just trying to point out without getting all technical is when using the LRC with the HRC bulkhead, don't use any shims on the inner camber link on the HRC bulkhead. If you are using the HRC, the you should start with 2mm shim on the inner link.

When switching from HRC to LRC, you can't lower the inner ball link lower than the height of the ball link mount on the gearbox unless you grind it down. What the new bulkhead does is lowers the inner ball link by
about 2mm, then in a sense providing a similar roll like that of the HRC setting. But there are a few differences. First of all the flex point is on the chassis and not the gear box, thus allowing the rear part of the transmission to flex more.
Secondly, the original HRC or plastic mount places the original chassis lower in relation to arm, while the LRC or -2mm raises the chassis higher, closer to the arm. This also affects CG and roll. But I am sure Fred can explain this more.

fredswain

iTrader: (1)

I actually wasn't directing that at you Dino but rather just throwing it out there for everyone to think about.

If you have one car with an HRC rear block running 3° of rear kick and you have another car with an LRC rear block that is also running 3° of rear kick, the car with the LRC block has less antisquat. I'm asking if anyone knows why? I know the answer but want to see if anyone else knows.

Dino_D

Ah, I see what you are trying to say.. Good point that you brought up. Having 1.5 antisquat in HRC and LRC will surely react differently, even if you kept the camber link geometry the same up top with the HRC bulkhead. I thought you were referring to just changing the rear block only. My bad.

Just throwing it out there as well. Whats most people common preference on low grip tracks? HRC or LRC. and on high grip tracks? LRC or HRC and why?

fredswain

iTrader: (1)

I'm not even talking about the upper camber link. What I'm saying is that if everything else stayed geometrically the same everywhere, but the only change was that one rear suspension was mounted 2mm lower on the chassis than the other, the lower mounted suspension would have a little less antisquat.

micholix

My guess it's because of the weight shifting, or the different CG, between HRC and LRC!?

JAE

iTrader: (30)

Being sold used but but apparently never run. Chassis is spotless. Seller says friend gave it to him and gearbox is almost locked? Have to replace the whole diff? I believe it is not a 2.0. It has the aluminum gold-type chassis. Selling for 125 bucks. Is it worthwhile? Looking to get into 2wd buggy as no one at my track races 4wd short course any more. Any advice also on a setup for about 300 bucks used for a 2wd buggy much appreciated. Looking to most likely run stock. Already have tx/rc don't need anything fancy but need to keep up and improve driving. Thx in advance!

WallyRC

Fred and Dino can you two help me out. Car is handling real well just need some more pack. Currently have 2x1.6 front/ 35 at. Rear: 2x1.7/30. Track is indoor, pretty smooth, big jumps. Fred I have read all your tuning threads and love them. I know small holes create more pack. Should I try 4 x 1.1 Front and 4 x 1.2 rear. Was going to order taper or drill out some of the blanks. Recommendations would be greatly appreciated. Thank you.

Dino_D

Use the same ratio but smaller and more holes. If you are using 2x1.7 approx 4.5 ratio, then 3x1.4 or 4x1.2

Diameter (mm) 2 3 4 5 6
1.0 1.571 2.356 3.142 3.927 4.712
1.1 1.901 2.851 3.801 4.752 5.702
1.2 2.262 3.393 4.524 5.655 6.786
1.3 2.655 3.982 5.309 6.637 7.964
1.4 3.079 4.618 6.158 7.697 9.236
1.5 3.534 5.301 7.069 8.836 10.603
1.6 4.021 6.032 8.042 10.053
1.7 4.540 6.809 9.079 11.349
1.8 5.089 7.634

If you see Chris D setup he runs 3x1.4 up front and 2x1.6 in the rear.

WallyRC

Thanks Dino
I know lighter oil packs more easily. With smaller and more holes does your oil weight go down or up in your experience?

fredswain

iTrader: (1)

The only things that matter are total hole area and oil weight. Less hole area is more pack but you'll need a lighter oil. It was once suspected that hole area wasn't significant on it's own and that the number of holes necessary to give you that area had a large role to play but that's turned out to not be true. I generally try to keep things similar though so if I'm using a 2 hole piston in front, I'll also have a 2 hole piston in the rear. The same applies to 3 or whatever. You get the idea. Don't buy into tapered pistons. They don't do anything. I stay simple. Good old straight hole pistons only.

WallyRC

Time to start tuning again. I run at NorCal hobbies. You can see the track online. Might start racing soon.
Thanks guys for all the input. Much appreciated.

WallyRC

Going to try and answer your question. All things being equal, the one with the LRC set up would have a higher COG. This I believe would take more force to get the same result as a vehicle with a lower COG. Even though they are both set at say 1.5 degree anti squat.
What ya think Fred?