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Old 01-26-2011, 06:40 AM   #1
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Default shock oil theory

I am curious as to why most setups you look at have a thicker oil in the front compared to the rear by usually about 5wt. What exactly is the theory behind this?
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Old 01-26-2011, 07:22 AM   #2
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It makes the car more forgiving and easier to drive, also the car feels more responsive.
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Old 01-26-2011, 08:07 AM   #3
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It also slows down weight transfer to the front under braking and can be used to make the car push a little on corner entry.
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Old 01-26-2011, 08:32 AM   #4
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+1 on the other 2 posts

and IMO it gives it more traction also.
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Old 01-26-2011, 08:56 AM   #5
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If you want to look onto more detail....

the leverage ratios of front and rear A arms are often different on most chassis. with the front usually having more leverage on the shock, requiring a stiffer shock either via piston or oil wt. So the front and rear can achieve balanced dampening rates or at least just feel the same.

Most drivers like a heaver "feel" up front to accomplish; what the earlier posters have stated, a more controlled weight transfer with the front.
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Old 01-26-2011, 11:51 AM   #6
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it also depends on the buggies characteristics.

the HB D8 on 99% of setups uses lighter fluid up front and thicker in the rear.
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Old 01-26-2011, 05:27 PM   #7
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Thanks for the responses guys.
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Old 01-26-2011, 05:28 PM   #8
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does the same go for 2wd sc trucks also which are baseilly staduim trucks ?
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Old 01-26-2011, 05:37 PM   #9
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4wd cars are pretty heavy in the front, and the front end tends to dig in when landing off jumps and on the take off too. this can cause the front to dive in the air or just scrape the ground too much...

I like a smaller hole piston in the front to keep the oil from being too thick and not react to the small bumps and ruts....Sometimes even a slightly stiffer sping can help too. for example, on the mugen I put the 6 hole pistons that are smaller than stock, and kept the oil at 40 instead of going to 45 or 50 because that would slow the action down too much, then I went up on the springs to keep the car from squating so much....to combat the reduction in turn in I put a thinner swaybar on the front. Sometimes a stiffer shock will react faster but have less overall traction....
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Old 01-26-2011, 06:57 PM   #10
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Quote:
Originally Posted by RePeTe View Post
it also depends on the buggies characteristics.

the HB D8 on 99% of setups uses lighter fluid up front and thicker in the rear.
when i ran HB i always flipped the shock fluids and it worked 100 times better, no push going in and out of turns. and it had more traction than i could ask for.

every single buggy and truggy i have ever had, i run the same all the way around or 5-10WT thicker in the front. always worked for me.
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Old 01-26-2011, 07:19 PM   #11
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Quote:
Originally Posted by jmaxey51 View Post
when i ran HB i always flipped the shock fluids and it worked 100 times better, no push going in and out of turns. and it had more traction than i could ask for.

every single buggy and truggy i have ever had, i run the same all the way around or 5-10WT thicker in the front. always worked for me.
I have always wondered how running heaver oil up front would work on the HB. I am going to have to give it a try because mine has a horrible push entering on power turns.
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Old 01-26-2011, 10:03 PM   #12
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Quote:
Originally Posted by jammin32j View Post
I have always wondered how running heaver oil up front would work on the HB. I am going to have to give it a try because mine has a horrible push entering on power turns.
also ride heights for the HBs never worked for me, i always ran it higher. another thing to try is more rear break. also if your running grey front springs on the buggy switch to white ... and yellow to the rear ... that took away all push. i even ran grey on the rear with short shocks with long truggy shock ends when traction was low.... personally i always hated the long rear shocks. however, i never ran with the hara buggy because i switched brands before the hara was out ...
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Old 01-26-2011, 10:13 PM   #13
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Quote:
Originally Posted by jmaxey51 View Post
also ride heights for the HBs never worked for me, i always ran it higher. another thing to try is more rear break. also if your running grey front springs on the buggy switch to white ... and yellow to the rear ... that took away all push. i even ran grey on the rear with short shocks with long truggy shock ends when traction was low.... personally i always hated the long rear shocks. however, i never ran with the hara buggy because i switched brands before the hara was out ...
I found I liked 29mm front and 31mm rear on my D8. And I ran 1.5 pistons up front and AE pistons drilled to 1.2 in the back with a heavier oil up front and the car worked way better for me like this.
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