BC Coilovers RH Type

[ALN]

Hello All,

I have a Lhd 78 280z with a v8 LS engine currently on a Tokico setup.
The dampers are now just about shot, so I am looking to install some BC Coilovers.

I'm after some advice on the spring rates. The recommended is 4/5Kg.mm but the blown V8 engine weighs circa 40KG more (dressed wet weight) over a L28.

Question is, should I be thinking of 5/5kg.mm instead?

Your educated feedback will be very welcome!

Thanks, Lionel

 

[Graeme - CZ]

Hi Lionel - I’ve just finished my BC install. Good choice. No complaints from me. I found the folks on the phone at BC were very helpful, when I had a similar question - though i just have an L28, so just went with the standard setup. Given the extra weight in your engine, going 5/5 may be the right thing to do. At the end of the day, you can adjust soft / hard ratio etc. I’d give BC a call if you have not already done so.

 

[ALN]

Thanks Graeme for the feedback. To be honest I followed your thread and that was one of the reasons I settled on BC (along with other research as well). I did call BC and they were helpful and said they would email me with more info after they spoke to the tech dept. Sadly Ive not heard, I will chase tomorrow.
Out of interest, do you have 55mm struts?

 

[Graeme - CZ]

Thanks Graeme for the feedback. To be honest I followed your thread and that was one of the reasons I settled on BC (along with other research as well). I did call BC and they were helpful and said they would email me with more info after they spoke to the tech dept. Sadly Ive not heard, I will chase tomorrow.
Out of interest, do you have 55mm struts?

When you say 55mm, do you mean my original struts which you cut off and the BC fits snugly over? Not sure of the diameter. My car is a 240z, so the struts are different width I believe. I see there is a specific BC for the 280z. I'm going to post some recent pics of my installation on that old thread if you are interested. It's been a big job, as I've replaced all bushes and bearings as I go, painting as I go and also stripped down and refurbished the whole backend including half shafts. 2 months from start to finish, working at weekends.

 

[ALN]

When you say 55mm, do you mean my original struts which you cut off and the BC fits snugly over? Not sure of the diameter. My car is a 240z, so the struts are different width I believe. I see there is a specific BC for the 280z. I'm going to post some recent pics of my installation on that old thread if you are interested. It's been a big job, as I've replaced all bushes and bearings as I go, painting as I go and also stripped down and refurbished the whole backend including half shafts. 2 months from start to finish, working at weekends.

Ah yes Graeme, the struts are different.
Sounds like quite an epic undertaking but glad that you are taking your time to be thorough. It will all be worth it in the end.
Are you using standard half shafts?
Was thinking of upgrading mines to cope with the torque, but that is another discussion entirely!
Have placed my order for the BC Racing Coilovers today, after speaking with James at their office. The conclusion was to start with 4/5kg.mm spring rate. Its relatively cheap to increase the rate to 5/5kg.mm. Works out to something like £70 for the front pair of springs.

I have the R32 big brake upgrade to do at the same time, all with new bearings and seals. Just wondering if I should upgrade the rears to discs at the same time.
Really after rear disc solution with a proper effective handbrake to match (after refurbishment the rear drum setup, the handbrakes are actually alright, I've found to my surprise!)

 

[Graeme - CZ]

Ah yes Graeme, the struts are different.
Sounds like quite an epic undertaking but glad that you are taking your time to be thorough. It will all be worth it in the end.
Are you using standard half shafts?
Was thinking of upgrading mines to cope with the torque, but that is another discussion entirely!
Have placed my order for the BC Racing Coilovers today, after speaking with James at their office. The conclusion was to start with 4/5kg.mm spring rate. Its relatively cheap to increase the rate to 5/5kg.mm. Works out to something like £70 for the front pair of springs.

I have the R32 big brake upgrade to do at the same time, all with new bearings and seals. Just wondering if I should upgrade the rears to discs at the same time.
Really after rear disc solution with a proper effective handbrake to match (after refurbishment the rear drum setup, the handbrakes are actually alright, I've found to my surprise!)

Glad you made some progress on the BC front. You won’t be disappointed. I’m very pleased with them. Yeah, sounds like the right thing re springs. Sounds like you may have more work at the back end than me. With a V8 up front, I’d maybe be considering replacing the whole drive train at the back whilst you do your brake conversion. I’ve read about a couple of Z’s that use a Subaru drive train at the back, though suspect a bit of fabrication is required on the control arms etc. I think if you were considering different half shafts anyway to deal with the tongue, replace the diff which something more modern while you are at it.

 

[Graeme - CZ]

Ah yes Graeme, the struts are different.
Sounds like quite an epic undertaking but glad that you are taking your time to be thorough. It will all be worth it in the end.
Are you using standard half shafts?
Was thinking of upgrading mines to cope with the torque, but that is another discussion entirely!
Have placed my order for the BC Racing Coilovers today, after speaking with James at their office. The conclusion was to start with 4/5kg.mm spring rate. Its relatively cheap to increase the rate to 5/5kg.mm. Works out to something like £70 for the front pair of springs.

I have the R32 big brake upgrade to do at the same time, all with new bearings and seals. Just wondering if I should upgrade the rears to discs at the same time.
Really after rear disc solution with a proper effective handbrake to match (after refurbishment the rear drum setup, the handbrakes are actually alright, I've found to my surprise!)

...and yes, i just have standard half shaft / diff. Well not exactly, i have the whole drive train from a 280z in my 240z.

 

[ALN]

Glad you made some progress on the BC front. You won’t be disappointed. I’m very pleased with them. Yeah, sounds like the right thing re springs. Sounds like you may have more work at the back end than me. With a V8 up front, I’d maybe be considering replacing the whole drive train at the back whilst you do your brake conversion. I’ve read about a couple of Z’s that use a Subaru drive train at the back, though suspect a bit of fabrication is required on the control arms etc. I think if you were considering different half shafts anyway to deal with the tongue, replace the diff which something more modern while you are at it.

The diff is made up of an OBX Helical LSD in a standard R200 Long nose case with 3.54 ratio gears. Have been assured that it will stand up to some abuse (not that my driving style is that hard). More concerned about snapping joints on the half shafts. Its making about 530 ft/lbs of torque and I find that it spins up rears far too easily. I have 225/50/15 profile tyres. If I went for wider stickier tyres, the shafts I suspect will let me down....