Nissan 370Z Forum - ARK-DTP Coilovers: Review & Initial Impressions

...finally got around to putting my ARK DT-P coilovers on this weekend. The DT-P is the track version of the ARK ST-P's, though the ST-P (street version) is not currently available for the 370Z. These were specially designed with input from a JDM Racing Team. Good enough for them, good enough for me. Colorful scheme in orange and contrasting black, if they perform as well as they look I'll be ahppy camper.

Standard, pillow ball top mounts also allow you a more direct feel for solid driver response. Might be too harsh for some as a DD, but I always remember a shirt one of my drummers wore back in my band days: "If it ain't stiff, it ain't worth a phuck". Seems appropriate for suspensions as well. :tup:

The clicker on top provides 16 levels of dampening adjustment, and adjusts compression and rebound simultaneously. The spring rates are a very beefy 12kg front and 10kg rear. Stiffest spring rates, by far, available at this price point. In the rear, the DT-P is a direct replacement for the OEM style rear damping system so the spring is separate of the shock and is not a "true" coilover. I think there are only a few manufacturers doing "true" coilover setups, Stance being one, but the majority of coilovers on the market today for our car are direct replacement in the rear, with a separated spring and shock.

http://www.the370z.com/members/sixpa...tp1-custom.jpg

http://www.the370z.com/members/sixpa...tp2-custom.jpg

http://www.the370z.com/members/sixpa...k79-custom.jpg

The clicker on the passenger side front is the most awkward to get to, but it's not too bad. I set the rears to softest before I put them on and did not remove any of the plastics from the rear while installing them because you don't have to. So going to cut some holes in the rear plastic in a few days to get to them easier. I am too lazy to remove the plastic every time I feel like changing the setting.

http://www.the370z.com/members/sixpa...ter-custom.jpg

It was somewhat of an adventure getting the rears figured out (had no directions) as far making sure the spring was not in upside down but after much review got it figured out that it could only go one way. You have to reuse the rubber deal that sits in the well at the bottom of the stock spring, and put the new spring on that with the flat part of the spring upwards into the new ARK collar. This bottom rubber piece easily comes off the stock spring, and it can only go back into the bottom well one way because it is step notched, so was easy for a dummy like me to not mess it up though it took awhile to get to that point after studying it.

http://www.the370z.com/members/sixpa...k77-custom.jpg

Only adjusted them one time after wheels back on and taken off jack stands. Spent alot of time measuring from several points on both the front and rear after they were all installed and still on jack stands. Was hoping to save time, as it is a pain with jack stands to get everything back on the ground, only to put it all back on the stands when you figure out one side is lower or higher than the other. So I think this strategy worked well.

First time down I was at LF 23 3/4, RF 23 1/4, RR 23 3/4 and LR 23 3/4. Rears being perfect, only had to jack up the LF in order to get it to match 23 1/4 ... down again was 23 1/8 so went a little too far. Left it alone for now and wait a week or so for any more settling to happen, and will measure all four corners again and adjust from there. It was easy to adjust the height, did not have to remove any hardware, like some of the Tein's.

My measurements are with the car on the ground, from the bottom of the wheel lip, straight up to the fender lips using the center cap as an intersect and midpoint. I noticed in lurking here that many folks measure from the ground up to the fender lips, but I don't think that is as accurate as using the bottom wheel lip and straight up.

http://www.the370z.com/members/sixpa...71-measure.jpg

Added some H&R Trak spacers to complete the look and performance, 15mm front and 20mm rear.

Almost wish I would have gotten 20's for the front as well after looking at it today. On the other hand, someday will be replacing the tires, and when I do I am going to go with 245 front and 275 rear (keeping my stock 18 wheels), so with a 245 on the front the 15mm spacer might look better. Here is a pic of the extended studs mounted on the rear...

http://www.the370z.com/members/sixpa...r11-custom.jpg

So here is what she looks like now:

http://www.the370z.com/members/sixpa...d44-custom.jpg

http://www.the370z.com/members/sixpa...d55-custom.jpg

http://www.the370z.com/members/sixpa...ear-custom.jpg

http://www.the370z.com/members/sixpa...7279-front.jpg

http://www.the370z.com/members/sixpa...47280-rear.jpg

One thing I noticed on the rear spacers, there was not a hole to be able to put these back. Not sure what they do, maybe some kind of tiny counterbalance ? If anyone knows what they are feel free to chime in. I am hoping they are not needed or are not important. Uncertain at this point if I perhaps got the wrong spacers for the rear.

http://www.the370z.com/members/sixpa...ers-custom.jpg

Can definitely tell a difference ! I have all of the coilovers set to click one (softest) ... might stiffen them a few clicks more as time progresses. Car is very responsive now, with a much less noticeable roll in corners, not that I did any hard core high speed stuff. Best way I can describe it is that it feels like a go-kart now. When I go to Summit Point at the end of April, that will be the real test. Not that I am race car driver or anything, but mainly I say this because I am entertaining letting my instructor (if they seem cool and are good) drive the car a few laps to see what they think.

Overall I am very happy with my DT-P purchase. Some major pro's listed below, and really only one minor con ... and I am confident we can get that right as well.

PROS:

Stiff spring rates

Superior customer service, communicating with ARK is fast and courteous

Easily raise and lower ride height without removing any hardware (Tein)

Fully rebuildable

15 month warranty versus 12 months for many others at this price point

CONS:

Not enough pictures in provided installation guidance

Did not come with nuts to re-attach the brake line blocks on the front, and OEM nut that comes off the stock assemblies is a different threadcount than the ARK stud. I have them zip tied right now, hoping that is not going to be a problem until I get a proper nut in the next few days (Stock=24 ARK=19)

http://www.the370z.com/members/sixpa...-ziptienew.jpg

... anyway, onward to getting some Whiteline sways and SPL parts done as soon as I can so I can take her to get an alignment.