That would be a thumbs down...

 

Pardon my ignorance, but why is this a bad thing?

 

Pardon my ignorance, but why is this a bad thing?
[/quote]


Well lad,

People such as myself that run in STR (their target market) have our ride height around 12.25-12.75 front and 12.5-12.75ish Rear. When the car is lowered in such a manner we require shorter shock shafts and shock bodys to still allow us to retain adequate shock travel to accommodate "large" bumps. When someone such as a company like this builds a shock with "stock" body length that means by lowering the car you are also lowering the about of shock travel. Do you see where this would be a issue?

Me for example, I own some billy badass triple adjustable JRZ. They have shorter then stock lenth bodys (I think, I'd have to double check with my notes) and at 12.5" all the way around I'm running into a shock travel issue with the rears. Last season I rebuilt them, I got them home and put them on the car at my 12.5 hub to fender height. I than realized I only have about 1.5-2" of rear shock travel. So I couldn't even put bump stops on them because that would limit them even more. I went all season with this "issue", now that the seasons over and I've DDed the car and raced on a couple bumpy slick lots that required me to take out compression to try to gain grip I've now got 2 in need of rebuild rear shocks.



I have also thrown away a couple races due to not being able to run low compression settings to gain grip or I've blown the whole day because I've had snap oversteer issues from bottoming out the shocks mid-corner and spinning. This winter I'm sending the rears back out to be cut down about .75" to allow about a 1" of travel. I want to be able to have the ride height set at 12.5" from hub to fender and have enough shock travel to be within a 1/4 of hitting the frame/inter fender with the top of the tire, then I'll but alittle bit bigger bump stops on the shock shafts to ensure that I never touch the "frame." This gives me the abillity to have a car thats set at 12.5" hub to fender but also have prolly 2.5" of usable shock travel. With a 800Lbs rear spring and 2.5" of rear shock travel I should never bottom out the shock. Ths enables me to be able to run very low compression for rain and slick lots, while not worring about damaging the shocks again.

I'm looking at $160 to cut each shock body, $160 each if they have to shorten the shock shaft, and $200 each for a rebuild. Thats $1040 not counting shipping to mod a shock to allow the ride height I desire. But at the end of the day I'll be happy because I'll be able to sleep at night knowing I don't have to worry about this issue again.

If you want to see pictures of my car at the current ride height look in "Josh7Owens JRZ thread", theres a bunch of pics and talk. This is the end of my first year doing shock tuning so I'm still a bit of a noob but I love to learn about stuff I'm interested in. As for why "we" don't want a shock that has the same freakin shock body lenth as the stock 4x4 shocks the answer should be obvious. Not one person in STR with high end shocks built with the "standard body lenth"

If I'm not mistaken the nick said "if he was going to stay with a S2000 he was cutting his shocks to 11.5" from the hole to the top of the body. I think I'm at 12" or so right now with the issues. It's posted somewhere in my thread.

Cheers buddy! Sorry if I come off harsh I'm craming for a test and been up all night.

 

Thanks for taking the time to break it down Josh.

I don't Autocross, I'm more of an amateur S2KI challange and HPDE type of guy. I have been considering taking the leap into the land of coilovers. These were on my short list and I am a total noob when it comes to this type of equipment.

Thanks again.

Dustin.

 

Why doesn't this issue arise on Motons? That design works as well on a BS car, as the lowered STR car.

interesting.

 

Moton body's are prolly already pretty short

 

Josh, I think you should try running bump stops on your JRZs, even if you shorten the bodies, for two reasons. Firstly, bump stops are a lot cheaper than rebuilding your shocks every time you guess wrong and bottom out. Secondly, I think you're discounting their value. You're describing them as if they take away travel, but (a) you don't really want to be playing in that last bit of travel anyway if you don't have bump stops because of the aforementioned risk of bottoming, and (b) while bump stops increase effective spring rate when they come into play, that can actually be a tuning tool in and of themselves -- Shaikh at Fat Cat Motorsports actually sells bump stops at different lengths and stiffnesses for specifically this purpose.

 

Remember that we're most interested in low speed damping for tuning handling. From the looks of the chart, they took a pretty small number of samples, and only one at a low speed, at a bit under 2 in/sec. (This is evidenced by the distinct "kinks" on the charts, all of which occur at the same shaft speeds for both compression and rebound.)

The ranges of adjustment for compression and rebound overlap slightly at their extremes at low shaft speeds, but that appears to be it -- at 2 in/sec, the compression adjustment (assuming the chart's correct, and going by eye) goes from roughly 100 to 280 lbs., while the rebound adjustment goes from roughly 25 to 125 lbs. The rebound forces do "catch up" to the compression forces at higher speeds because the compression curves are slightly digressive, but the compression forces are still very high -- I'm a bit puzzled about why people are saying that these shocks ride comfortably when they have high-speed compression forces as high as they do.

Just to be clear, I'm not saying the shocks are valved wrong. If the graphs are right, however, the shock valving Evasive chose is very unusual, so it would be interesting to hear from them why they chose to go this route.

 

Pedalfaster- once the body's are cut I will run bumpstops to ensure I don't bottom them out again. I though I said that in my post but I might not of.

I'm running my compression 2 clicks softer then the shock dyno that was posted up of my shocks. I don't think I could live with that much compression at highway speeds. If I hit a big bump on tge interstate it already bounces me pretty good.

I also think that at that these shock and a high spring rate s2000 in str would have a hard time having grip on a slick lot if the speeds got up there. My car anything over 7-8 clicks of compression on a normal course seems to not have as much grip as it does with the compression in the 6 range. I also don't run more then 1-2 clicks of low speed compression because of this.

 

hey guys im about to upgrade coilovers and undecided about whether i should go the normal tein src or these evs spec eibachs...whats everyone think