Ohlin R/T, JRZ RS1 or Nitron R1s?

[biggynuts01]

Guys I need help. Im planning on getting a new suspension kit this coming spring season. I know the quality of the JRZ R1s from reading all the great reviews. And the Ohlins sound like the perfect street set up but not the best for track.

I emailed Steve at VacMotorsports and He said the Nitron R1s are "Pro Grade" Technology. He also said that they run them in there race cars and think they are better than the TCK DAs. For $2600 they sound like a pretty good deal. They are also single know double adjustable which i prefer.

Any one know anything about Nitron R1s? Are they quality kits?

http://store.vacmotorsports.com/nitr...-1m-p2804.aspx

TIA!

[italyix]

From my understanding, Nitro is a serious coilover kit. Most if not all of the Lotus guys run Nitron.

I'd love to know the answer to this, as you have picked exactly the three choices I was looking into as well.

I also noticed that Nitron come as full coilovers, both front and rear...might just be the pictures misleading though, but it seems the UK guys love them

[highlandsM3]

They are top shelf for quality.

from http://www.simplysportscars.com/inde...emart&Itemid=1

"NITRON AND LOTUS
Nitron are proud to announce that they have been appointed the official upgrade dampers for the new Lotus Exige V6 race cars, displacing tough international competition."


Im currently trying to decide between the Nitron R3 setup or PSi Ohlins setup.

[Beedub]

ive spent lots of time @ nitron HQ here in the UK when i wanted them to build me a z4m setup (i went with kw CS in the end due to needing the seperate barrel spring) and i was blown AWAY!!! Very very serious stuff, and the quality is imo second to none.

[biggynuts01]

Great feedback. Seems like Nitrons are very highend and I would like to try them just because not many people in the US have them.

Now, my only concern is finding out if VAC motorsports is a authorized service center for Nitron. I would only buy if there is a local (USA) service center since I don't want to have to ship my shocks to the UK for servicing.

[marktapscott]

Originally Posted by biggynuts01

Great feedback. Seems like Nitrons are very highend and I would like to try them just because not many people in the US have them.

Now, my only concern is finding out if VAC motorsports is a authorized service center for Nitron. I would only buy if there is a local (USA) service center since I don't want to have to ship my shocks to the UK for servicing.

Hi there,

Quick introduction - Mark from Nitron (UK). I lurk around here as I drive an E46 M3 and its great place for inspiration!

Just wanted to note that Nitron do indeed have several service centres in the US. We intend on establishing a Nitron North America for this exact reason you point out - to support our US dealers, improve delivery times and establish local full factory support and servicing facilities.

Until that happens, there are two primary and official service centres East/West coast. I do not want to be seen promoting so I will allow those interested to contact their dealers for further details.

PS - We plan to improve upon our European race wins and our BMW Nurburgring lap record again this year with the F10 / E9X platforms....

Hope that helps - Thanks!

[biggynuts01]

Originally Posted by marktapscott

Hi there,

Quick introduction - Mark from Nitron (UK). I lurk around here as I drive an E46 M3 and its great place for inspiration!

Just wanted to note that Nitron do indeed have several service centres in the US. We intend on establishing a Nitron North America for this exact reason you point out - to support our US dealers, improve delivery times and establish local full factory support and servicing facilities.

Until that happens, there are two primary and official service centres East/West coast. I do not want to be seen promoting so I will allow those interested to contact their dealers for further details.

PS - We plan to improve upon our European race wins and our BMW Nurburgring lap record again this year with the F10 / E9X platforms....

Hope that helps - Thanks!

Mark, I am very glad that you decided to post! Can you tell me store address of the West coast service center?

[italyix]

Originally Posted by biggynuts01

Can you tell me store address of the West coast service center?

Interested as well, thanks!

[flipm3]

Originally Posted by biggynuts01

Mark, I am very glad that you decided to post! Can you tell me store address of the West coast service center?

Originally Posted by italyix

Interested as well, thanks!

I quickly hopped onto their UK site and it looks like Sector 111 is located in CA, although seems to specialize in Lotus.

Then there is VAC Motorsports in PA, that obviously specializes in BMW.

They all seem to be dealers, so not sure if the service centers are different.

[italyix]

Originally Posted by flipm3

I quickly hopped onto their UK site and it looks like Sector 111 is located in CA, although seems to specialize in Lotus.

Then there is VAC Motorsports in PA, that obviously specializes in BMW.

They all seem to be dealers, so not sure if the service centers are different.

Flip, ty

I researched these a bit more today and noticed VAC also offers them as a true coil over, rear wise.

I also could not find anything relating to the E90 platform as having the dreaded subframe issue the E46 had. Am I correct to assume we can safely and reliably run a coil over in the rear instead of the oem setup?

Perhaps VAC can chime in...

If so, I'm pulling hte trigger on the R1S+ come next year...

[chuxdelux]

I talked to the guys at VAC a couple of months ago at length about the Nitron R3s. They had nothing but good things to say about this suspension. I will be pulling the trigger on these after the new year. Maybe we should get group buy going.

[marktapscott]

Hi All,

Coming from the UK and understanding very clearly the issues of 'advertising' on forums, I am afraid I will have to refrain from mentioning any businesses in my post here.....

I would like to maintain my position as a technical factory resource for fitting/setup advice etc and avoid sales entirely. - I can do this as we already have a great BMW partner (some of you have already had contact with them) that will be able to answer your commercial questions. I hope you appreciate my stance on this.

Of course, when the time is right; I anticipate Nitron achieving 'advertiser' status on the forum.

The technical.....

As mentioned, I have an E46 M3 - which also means I have the rear subframe cracks! Infact, they have just started to appear following a heavy UK track day to compound this problem. I look forward to a weekend of welding reinforcements in January!

I run coilover rears with a relatively stiff spring rate (Track day rates), every day.

Rear coilovers -

Advice is really dependent on expected use. The 'issue' of running a coilover rear-setup without a rear roll-cage is of course that the turrets are not designed to cope with both damping and resultant spring forces. By considering both the spring rate used and (significantly) the weight of the vehicle we/you can judge what is appropriate. If you plan to ride 5-up, with luggage around the Nurburgring - then we would of course recommend that the car is either a non-coilover or the rear-turrets are reinforced - no matter which platform you have.

The E46 is known for having well constructed turrets (if not the subframe!), as is the case with the E9X. Nitron would not naturally recommend running stiff rear coil-overs on an E36 that has not been reinforced.

When running slicks - again, the advice would be to reinforce.

Having said all that; we know of many customers in Europe running coilover rear setups in M's without reinforcement or issue for many years.

A point worth making is that Nitron kits are all hand built to order and specification. As such we can create 'hybrid' kits that comprise of solid front top plates (camber/castor adjustable) with the rear as either a separate system or coilover. Further to that, the rear damper can be specified to either mate with the OE rubber top mounts (for mainly street driving) or with a full race bearing top mount. Both have their pros/cons, however I personally mated my rear shocks to a new set of rubber OE mounts. This results in mainting OE NVH and adding an extra level of compliance without sacrificing track performance dramatically. Of course, serious track cars and race cars will benefit from the spherical bearing mounts considerably.

As mentioned; our US BMW distributor is well worth contacting directly as they have a wealth of knowledge and have been running Nitron on their own cars for some time.

Hope that helps in some way?

Thanks!

[M3SQRD]

Another damper to consider is the MCS SA non-remote damper. I'm not sure if MCS has released the e9x M3 SA version yet (I believe both e36 and e46 M3 SA dampers have been released) - if not, it should be released soon. Its price is ~$150 more than the RS1 damper...

[Skyarb]

I recommend Nitron. I use them for 5 months, and I'm very happy. It's hard to compare to Ohlins Road and Track, as I've never tested Ohlins.

[italyix]

Marktapscott, thank you for your explanation and keeping the thread strictly technical.

When you mention running stiff spring rates in the rear as a coil over unit, can you define what stiff means to you? 500lb? 800lb? Also, how are motion ratios affected (if at all seeing how pivot points are unaltered) by running a coilover in the rear? I think the oem rear set up ration is something like .5 to 1. If the motion ratio changes by changing the coiover set up, could we then run softer (or stiffer depending on the change) rear springs? thus saving the rear towers from added stress?

Just looking into all the scenarios as I would like to run a coil over in the rear if I can, without having to worry about cracks in the towers. Can has 62k highway miles, so not hard miles at all.

Thanks!

EDIT: I just read: http://www.m3post.com/forums/showthread.php?t=339168 which explains suspension types. I will be going rear coil over to solve the motion ratio and spring rate issues.

[e679]

Originally Posted by marktapscott

Hi All,

Coming from the UK and understanding very clearly the issues of 'advertising' on forums, I am afraid I will have to refrain from mentioning any businesses in my post here.....

I would like to maintain my position as a technical factory resource for fitting/setup advice etc and avoid sales entirely. - I can do this as we already have a great BMW partner (some of you have already had contact with them) that will be able to answer your commercial questions. I hope you appreciate my stance on this.

Of course, when the time is right; I anticipate Nitron achieving 'advertiser' status on the forum.

The technical.....

As mentioned, I have an E46 M3 - which also means I have the rear subframe cracks! Infact, they have just started to appear following a heavy UK track day to compound this problem. I look forward to a weekend of welding reinforcements in January!

I run coilover rears with a relatively stiff spring rate (Track day rates), every day.

Rear coilovers -

Advice is really dependent on expected use. The 'issue' of running a coilover rear-setup without a rear roll-cage is of course that the turrets are not designed to cope with both damping and resultant spring forces. By considering both the spring rate used and (significantly) the weight of the vehicle we/you can judge what is appropriate. If you plan to ride 5-up, with luggage around the Nurburgring - then we would of course recommend that the car is either a non-coilover or the rear-turrets are reinforced - no matter which platform you have.

The E46 is known for having well constructed turrets (if not the subframe!), as is the case with the E9X. Nitron would not naturally recommend running stiff rear coil-overs on an E36 that has not been reinforced.

When running slicks - again, the advice would be to reinforce.

Having said all that; we know of many customers in Europe running coilover rear setups in M's without reinforcement or issue for many years.

A point worth making is that Nitron kits are all hand built to order and specification. As such we can create 'hybrid' kits that comprise of solid front top plates (camber/castor adjustable) with the rear as either a separate system or coilover. Further to that, the rear damper can be specified to either mate with the OE rubber top mounts (for mainly street driving) or with a full race bearing top mount. Both have their pros/cons, however I personally mated my rear shocks to a new set of rubber OE mounts. This results in mainting OE NVH and adding an extra level of compliance without sacrificing track performance dramatically. Of course, serious track cars and race cars will benefit from the spherical bearing mounts considerably.

As mentioned; our US BMW distributor is well worth contacting directly as they have a wealth of knowledge and have been running Nitron on their own cars for some time.

Hope that helps in some way?

Thanks!

May I ask if 335 E93 may convert to coilover rear? If yes, which spring rate is a safe bet? Thanks.

[italyix]

^^i think you can, I calculated the rear springs would need to be 600lb if using a coil over setup, so they would match the fronts of 500lb. The equivalent oem style rear spring would have to be 1200lb to match the front. At 600lb I do not thing the rear towers would give in, seeing how the gts runs a rear coil over. If you then factor in sway bars, in my case RD sport, I calculated again the front would need to be at hole 1, and the rear would have to be at hole 3, to match spring rates and effectively giving, at 2" of deflection or compression, a total of 1200lb spring. I hope this makes sense :/

[M3SQRD]

Originally Posted by italyix

^^i think you can, I calculated the rear springs would need to be 600lb if using a coil over setup, so they would match the fronts of 500lb. The equivalent oem style rear spring would have to be 1200lb to match the front. At 600lb I do not thing the rear towers would give in, seeing how the gts runs a rear coil over. If you then factor in sway bars, in my case RD sport, I calculated again the front would need to be at hole 1, and the rear would have to be at hole 3, to match spring rates and effectively giving, at 2" of deflection or compression, a total of 1200lb spring. I hope this makes sense :/

I think your calculations are not correct.

The wheel rate = spring rate*motion ratio^2
The stock motion ratios are:
Front coilover ~0.96
Rear non-coilover ~0.58

A commonly used e9x M3 dual-purpose (street-track) setup uses 500 lbf/in F and 800 lbf/in R spring rates which converts to F and R wheel rates of ~460 lbf/in and ~270 lbf/in, respectively.

Assuming the rear "coilover" motion ratio is the same as the front coilover motion ratio (0.96, assumption; the actual value is probably between 0.7-0.85?) the rear "coilover" spring rate would be...spring rate = wheel rate / motion ratio^2 - assuming you want to match the commonly used non-coilover R setup of 800 lbf/in, the R "coilover" spring rate would be ~293 lbf/in (see below for R rate based on the correct R damper motion ratio).

I'm not going to factor in effective spring rates from the F and R sway bar torsional stiffness because they are fixed (only one end link mounting hole per bar end; not everyone is using adjustable F & R sway bars) regardless of whether you run a rear non-coilover or coilover setup. However, I will say that one of the most important things that's commonly neglected when it comes to sway bars on lowered cars is the proper re-adjustment of the sway bars, using adjustable threaded end links, to prevent the sway bars from binding - very important on the F bars because the stock sway bar mounting bushings are extremely tight (i.e., no clearance).

UPDATE: found out the rear damper motion ratio is 0.83. This means if you wanted to match the stock rear spring rate of 800 lbf/in used in the example above in a rear "coilover" setup, the "coilover" spring rate would need be ~392 lbf/in.

[biggynuts01]

Originally Posted by marktapscott

Hi All,

Coming from the UK and understanding very clearly the issues of 'advertising' on forums, I am afraid I will have to refrain from mentioning any businesses in my post here.....

I would like to maintain my position as a technical factory resource for fitting/setup advice etc and avoid sales entirely. - I can do this as we already have a great BMW partner (some of you have already had contact with them) that will be able to answer your commercial questions. I hope you appreciate my stance on this.

Of course, when the time is right; I anticipate Nitron achieving 'advertiser' status on the forum.

The technical.....

As mentioned, I have an E46 M3 - which also means I have the rear subframe cracks! Infact, they have just started to appear following a heavy UK track day to compound this problem. I look forward to a weekend of welding reinforcements in January!

I run coilover rears with a relatively stiff spring rate (Track day rates), every day.

Rear coilovers -

Advice is really dependent on expected use. The 'issue' of running a coilover rear-setup without a rear roll-cage is of course that the turrets are not designed to cope with both damping and resultant spring forces. By considering both the spring rate used and (significantly) the weight of the vehicle we/you can judge what is appropriate. If you plan to ride 5-up, with luggage around the Nurburgring - then we would of course recommend that the car is either a non-coilover or the rear-turrets are reinforced - no matter which platform you have.

The E46 is known for having well constructed turrets (if not the subframe!), as is the case with the E9X. Nitron would not naturally recommend running stiff rear coil-overs on an E36 that has not been reinforced.

When running slicks - again, the advice would be to reinforce.

Having said all that; we know of many customers in Europe running coilover rear setups in M's without reinforcement or issue for many years.

A point worth making is that Nitron kits are all hand built to order and specification. As such we can create 'hybrid' kits that comprise of solid front top plates (camber/castor adjustable) with the rear as either a separate system or coilover. Further to that, the rear damper can be specified to either mate with the OE rubber top mounts (for mainly street driving) or with a full race bearing top mount. Both have their pros/cons, however I personally mated my rear shocks to a new set of rubber OE mounts. This results in mainting OE NVH and adding an extra level of compliance without sacrificing track performance dramatically. Of course, serious track cars and race cars will benefit from the spherical bearing mounts considerably.

As mentioned; our US BMW distributor is well worth contacting directly as they have a wealth of knowledge and have been running Nitron on their own cars for some time.

Hope that helps in some way?

Thanks!

What are the spring rates of the front and rear springs supplied with the "BMW E90/E92 M3 - NTR R1" Kit?

[biggynuts01]

Originally Posted by M3SQRD

I think your calculations are not correct.

The wheel rate = spring rate*motion ratio^2
The stock motion ratios are:
Front coilover ~0.96
Rear non-coilover ~0.58

A commonly used e9x M3 dual-purpose (street-track) setup uses 500 lbf/in F and 800 lbf/in R spring rates which converts to F and R wheel rates of ~460 lbf/in and ~270 lbf/in, respectively.

Assuming the rear "coilover" motion ratio is the same as the front coilover motion ratio (0.96, assumption; the actual value is probably between 0.7-0.85?) the rear "coilover" spring rate would be...spring rate = wheel rate / motion ratio^2 - assuming you want to match the commonly used non-coilover R setup of 800 lbf/in, the R "coilover" spring rate would be ~293 lbf/in.

I'm not going to factor in effective spring rates from the F and R sway bar torsional stiffness because they are fixed (only one end link mounting hole per bar end; not everyone is using adjustable F & R sway bars) regardless of whether you run a rear non-coilover or coilover setup. However, I will say that one of the most important things that's commonly neglected when it comes to sway bars on lowered cars is the proper re-adjustment of the sway bars, using adjustable threaded end links, to prevent the sway bars from binding - very important on the F bars because the stock sway bar mounting bushings are extremely tight (i.e., no clearance).

Very good info. Thanks!

[M3SQRD]

Originally Posted by biggynuts01

Very good info. Thanks!

So far I've made an assumption on what the rear damper motion ratio is based on it being outboard of the spring (closer to the wheel) and at an angle closer to vertical compared to the spring. With a few simple measurements it wouldn't be difficult to calculate the rear damper motion ratio.

Nevertheless, for a street car, or even a dual-purpose car, I do not see an advantage of running a rear coilover setup over a stock rear setup, especially on a car without a stiffened rear shock tower. On my old e46 M3 after having a custom welded-in roll bar installed I discussed switching to a rear coilover setup with a shop that professionally races BMWs and they said there was really no performance advantage for a "street" car. I know certain people have stated it's "ok" to run a rear coilover setup on the e9x M3 but I bet if the shock tower were to fail they wouldn't repair the damage for free...

[italyix]

My calculations were based on matching the front 500lb spring with a rear of 600lb using a rear coil over set up, given a motion ration of .83 for the rear.