Suspension Setup For R34 Gtr V-Spec2 Daily Driver

[guppy]

I imported an R34 GTR V-Spec2 last year and it came with HKS Hipermax 2 suspension fitted.

The left rear shock has blown a seal so I'm going to replace the suspension.

Did a search and read through this topic:

http://www.skylinesaustralia.com/forums/topic/374385-bilstein-coilover-conversion/

Need people's advice/experience.

My plan is to get Bilstein B6 shocks:

Front part No. 24-021074 (old part no. B46-2107)

Front part No. 24-021081 (old part no. B46-2108)

and:

ISC rubber mount strut tops to suit 2.5" spring
Sleeves to suit Bilstein shock (A1 racing, part no. A1-12451)
2.5" lower perch to suit sleeves (A1 racing, part no. A1-12460)

bushes & washers to suit

I'm not sure what spring rates or lengths to use yet.

Based on what other people have used, and the fact that the BNR34 is heavier, I'm guessing 325 lb/inch front and 275 lb/inch rear?

And will these spring rates work OK with the Bilstein shocks or will I need to have them re-valved?

As far as the spring lengths go, I figure I'll get the shocks all assembled then work out how long they need to be.

For the bump stops, where do I get them from so I can cut to suit the block height?

And is 30mm about the right measurement to avoid block height occurring?

And excuse my ignorance, but what fixes the sleeve to the shock? I see mention of having to have grooves machined in the shock body to accept a circlip but I can't picture how this works.

Where's the best place to order the shocks and springs from?

Edited October 14, 2013 by guppy

[djr81]

I'm not sure what spring rates or lengths to use yet. As far as the spring lengths go, I figure I'll get the shocks all assembled then work out how long they need to be.

For length your choice with an Eibach spring is either 8" or 10". 10 for the back easy, 10 for the front if you can. Both may need the extra groove put onto the shock body to accomodate them. Would suggest 10" all round but the front ride height may be a problem so get the grooves put under the existing ones (down aways too). How long is your sleeve?

Based on what other people have used, and the fact that the BNR34 is heavier, I'm guessing 325 lb/inch front and 275 lb/inch rear?

And will these spring rates work OK with the Bilstein shocks or will I need to have them re-valved?

6kg/mm & 5kg/mm are reasonable numbers. Bilsteins will be fine in this range. You would be surprised how large a srping variation they can accomodate.

For the bump stops, where do I get them from so I can cut to suit the block height?

And is 30mm about the right measurement to avoid block height occurring?

Stock bump stops are good if you have them. You have to try before you can get them to length. This is a pain but has to be done.

And excuse my ignorance, but what fixes the sleeve to the shock? I see mention of having to have grooves machined in the shock body to accept a circlip but I can't picture how this works.

If you have a look at the other thread the photo in post 12 shows the circlip in the top groove. Tiny circlip is tiny but is trappped by the bottom of the sleeve.

[guppy]

OK thanks Richard.

Do you have an opinion on the different types of nuts for the threaded sleeves? I think I'd prefer the two locking nuts as opposed to the single nut with what appears to be a grub screw to lock the nut onto the sleeve. But most of the threaded sleeves I come across on the net are the latter type.

[djr81]

Not really, no. I have the two lock nut type but they can be a bitch to get off and sometimes a bitch to get enough torque on them to tighten properly. The other type there is a bit of a worry about hurting the thread. But ultimately I dont suppose it matter much either way.

[guppy]

yeah the grub screw on the thread was what I was worried about. will see what I can find.

[guppy]

can get nylon-tipped grub screws so should be ok:

http://www.smallparts.com.au/store/partslist/socketsetscrewsnylontippedalloysteel/socketsetscrewsnylontippedalloysteel/all/1/