(Update Sept 2022)
F31roger’s S13 suspension experience
I recently used S13 components to lower my M30. I was desperate and used old stuff for the most part to get it put together (for JCCS), but at least I can do a decent write up with a bit more detail in parts (not pictures). As I pieced everything together, I noticed that I was missing crucial parts that other write ups never mentioned. Those guys probably had everything on hand. I found out the hard way and I wanted to highlight those lessons.
S13 components used:
- BC Racing coil overs (s13 BR series)
- S13 knuckles (non abs)
- S13 front hubs (non abs) > S13 ABS hub (post event)
- S13 OEM lower control arms with new ball joints
- S13 inner tie rods – (ISR upgrade)
- S14 outer tie rods – (Circuit sports – suggested S14 outers with ISR s13 inners)
- S13 tension rods – (Megan racing).
- Nissan Washer front bearing – 40264-F6600 x2 (post event)
- Nissan Nut lock Front wheel bearing – 01225-00541 x2 (post event)
- S13 wheel studs – 43222-50J00 (front hub)
- S13 front dust boots
- S13 front wheel bearings (for refresh)
Note – I pieced these together with mostly used parts. (besides the inner/outer tie rods being new).
Tools:
- Usual socket set and screwdrivers.
- Bigger sockets such as 20-30mm (I do believe 24 and 30mm were used)
- Ball joint removal (just incase)
- Tie rod removal tool (for sure)
- Drill (for rear)
- Torque wrench
FRONT COIL OVERS
S13 Front coil overs (BR series are fully adjustable) and work when other S13 components such as knuckles, hub and tie rods are used. Luckily the threads on both of these and the collars weren’t bad or seized up. Soaked in PB Blaster, but also taken apart and cleaned with degreaser to get them smooth moving.
- Note – top strut nuts are different between the S13/F31.
- Note – My coil overs has a blown shock in the driver side. BC Racing sells new pieces separately. One shock is $95.
- Note – The electronic dampener on the top of the OEM M30 shock tower will be removed.
REAR COIL OVERS
To get to the top of the rear suspension mounts, you have to remove the rear deck lid.
When using S13 coil overs, you do have to drill a hole as the S13 and F31 use different configuration. This was difficult in a pinch and I didn’t think it out. What I did was with it lowered, I used a paint pen, and dabbed paint on top of the one stud and marked where I needed to drill. Once I did that, I drilled it out.
Besides coil over, nothing else is S13 in the rear. M30 rear hubs, disc brakes and calipers are the reinstalled.
- Note – top strut nuts are different between the S13/F31.
- What I am doing now is getting the rear spacer/adapters that was used in Project Leopard, made. I that would have made the whole process easier and make it more balanced as I didn’t want to slam and tuck my wheels.
S13 KNUCKLES
My buddy Edrik gave me a set of OEM S13 knuckles. The bolts from the knuckle to the coil over (Two I believe) are needed (we were in a rush, so I couldn’t fully document them at the time).
- *You have to cut the dust shields on the S13 knuckles
S13 FRONT HUBS (4 lug non ABS) AND PARTS
Edrik gave me some Non ABS hubs with the knuckles. Since they were offered for free, I just took them. When it was time to use them, I had a couple issues (not blaming Edrik).
One thing, I noticed one of the hubs had cut studs. Whoever gave these to Edrik possibly used a spacer and cut them short. *I ordered new ones to replace those with. Since it was crunch time, I was desperate and actually bought a set of s13 front and rear hubs for $80. Also non ABS.
When we started to put these together, I found out that I was missing a few pieces.
- Nissan Washer front bearing – 40264-F6600 (2 for each side)
- Nissan Nut lock Front wheel bearing – 01225-00541 (2 for each side) *30mm socket
- Pin and dust cover (which I reused).
The washer and nut lock were the biggest thing.
Update – ABS Hubs ordered.
In California, we have to get a our cars smog checked (such an F’n hassle) and they always check all the instrument warning lights. I personally like ABS, so I decided to pony up and get a set. I looked on Ebay and FB marketplace and just the hubs themselves were $120 each (used at that!). I looked at Croooober and not only did I find a set of ABS hubs, they also come with knuckles the above mentioned hardware.
I also plan to refresh these hubs regardless as I feel that while things are out, either rebuild or renew. The wheel studs and hubs are a bit crusty, so I want to make it new. While at it, I plan to put in new wheel bearings.
This video was super convincing and helpful! S13 Front Wheel bearing replacement
I plan to clean these up pretty good and even paint them. Since I am unfamiliar, I want to see how the ABS exciter ring is on the hubs and will see if they can be transferred to a newer, non abs hub.. but not to worried if it doesn’t.
I’ve ordered 2 front wheel bearings from Rockauto for refreshing.
S13 FRONT LOWER CONTROL ARMS
I got brand new OEM front lower control arms with new S13 ball joints and castle nuts.
S13 TENSION RODS
I am using S13 tension rods that Caleb got. M30’s can work, but just incase, we swapped out. We had a clearance issue, the front sway bar had to be removed (this is something I will look into). I generally want to keep the front sway bar because I wanted to have a stiffened front end.
S13 INNER TIE RODS
I went with ISR’s inner tie rods because they were suppose to be a bit beefier than OEM. I got 2 sets for both Project Leopard and Project Diplomat. The set didn’t work on Project Leopard due to the modified knuckles, so I took both of the ISR sets with me to the bay area. *There was a note when purchasing these that you must use S14 outer tie rods or aftermarket S13 outer tie rods.
* Fortunate to have new dust boots as well.
S14 OUTER TIE RODS
I found someone selling new S14 outer tie rods, so I jumped at getting them. I got an extra set (for my other ISR set) plus a few other inners and offset rack spacers.
** If I had to do it over again **
- GKtech’s extended inner tie rods
- GKtech’s outer tie rod ends optional different length shanks.
I just feel that these would have been a better deal overall.
F31 FRONT BRAKES
M30 Front brake calipers, brackets and rotors can be used with this set up. Using the S13 knuckle will change the front caliper’s position to the back.
*Keeping 4 lug configuration might hinder clearance issues.
FINAL NOTES
Besides the swapping of parts, It’s all pretty much all there. There are a few things I want to do better next time, but one of the biggest things is I’ll probably have my fenders rolled.
I was rushing with the swap and it took a few days of late night/early morning time frames. It sucked. I had a ton of help from good friends and I was lucky to get some of the parts on short notice.
Credits: Edrik (knuckles and hubs), Colin (hubs), Reg (S14 outer tie rods), Masai (S13 FLCAs), Malik and J (for their time and help) and Caleb (for letting me borrow his stuff off his M30)
OG S13 Suspension Coilover Installation (Thanks to Brian “DoriSlutM30”)
S13 coilovers
S13 inner and outer tierods
S13 control arms
the tension rods are m30 and so is the thing that goes from the control arm to the sway bar
S13 knuckle (i think its called). it has the hub on it. and you need the two bolts that go from the knuckle to the coilover.
the caliper and rotor are M30
do what you want with these (ABS & dampening control)
you have to gut the back to get to where the strut tower mount is and drill a hole
here’s what i started with
Here’s the finished product
Drew’s step by step for M30 Convertible
Project S13 Coilovers – completed 9/24/2006
Having a crappy suspension with 15 year old shocks is not good. The OEM replacement sonar suspension shocks are about $2500 a set and really aren’t that good anyway. A nice set of coilovers can be had for about $1,000. I opted for that. In order to get coilovers in your M30 you need to do a few tricks. For the fronts, you need to obtain the inner and outer tie rods, lower control arm and spindles/hubs assembly from a S13 240sx (89-94?). The rest of your M30 stuff can be used and its quite a simple swap, just requires some time and patience. Installing the rear coilovers requires some minor customization and is also quite simple. Getting to the rear shocks on a convertible, well that�s a bit more tricky but we will cover that.
I purchased a set of KTS coilovers for an S13. They are pretty reputable, have good support in the US and can be refreshed with new dampers for about $400 for all four. Not bad. They come with a 6/8 kg spring set and will set you back about $1,100.
For the fronts, the parts list from Dorislut on www.f31club.com is perfect. I had everything I needed.
Remove the stock parts – easiest way is to remove the two nuts for the sway bar end link, remove the two nuts to the tension rod, remove the INNER control arm from the rack (don’t bother with the outer link, you won’t be using any of this so remove as an assembly), remove the ABS sensor from the M30 spindle assembly and get it out of the way. You won’t have antilock brakes anymore. Remove the brake caliper� and hang out of the way with wire, remove the rotor, remove the bolt for the lower control arm, remove the three nuts under the hood holding the top of the strut, stand back as it is going to all drop at once. Throw this shit out.
This is the S13 lower control arm, tension rod (I used the M30 tension rods) and spindle/hub assembly. Install this.
The coil over will pop right in and bolt up to the s13 parts. Reinstall the caliper and disk, note that the caliper will be on the opposite side of the wheel now. No problems, just bolt it on.
Fronts took about 6 hours, including pulling the parts at the junkyard. I think I could probably do it in half that time now that I have done it once. Not easy, but not really hard either. I had problems with some bolts on the M being very difficult to remove. The rest was straightforward.
For the rears – the convertible M30 is not so clean when it comes to accessing the rear struts. This will get it done:
First, put the top down. Remove the bottom of the rear seat, just pull on it and it pops out. Now put the top up, and remove the four nuts that hold that back seat in. You will need a long extension and a u-joint adaptor to reach the ones on the bottom. You will need to crawl into the trunk like a dead guy in New Jersey. I could not even get a picture of them. They are black nuts and 14mm. Once you have these out remove the rear seat, you should now have this:
Remove these screws from the plastic cover:
Now go crawl back into the trunk and remove the same screws from the other side. The plastic piece should come loose and you can slide it down the seatbelts out of the way. You could remove it entirely by removing the seat belts, but I didn’t bother. Just get it out of the way.
Now you can access the struts – there is some funky rubber foam covering them up – move it out of the way:
Remove the screws from the actuator and remove the actuator.
At this point you can work with the top up or down. It’s easier with the top down for me. Just tuck the headliner out of the way around the strut tower. See the ears that the actuator was screwed to – if you want to reuse the struts, you need to remove the nut and pull this off in order to get the strut out. If you don’t care, just take vice grips and bend them up.
Now you want to jack up the rear of the car and put it on jack stands, remove the rear wheels. Undo the lower strut (17mm one bolt). Remove the three nuts up top and remove the strut.
Here is the side by side on your new v. old:
As you see, the s13 strut uses only two bolts. Also, the bolts are smaller for the s13 so your M30 nuts won’t fit. I used 4 nissan 12MM nuts that I found lying around in my box of bolts.
Measuring the new strut, you will find that bolt center to bolt center is about 3 1/8″. You need to make the new holes to meet with this width.
Use one of the existing holes, and drill a new hole on the other side. You can see where I marked it up.
Use a round bastard file to slot the existing hole towards the other hole until it meets with your mark. You can now install the strut. I removed the lower strut mount from each of the struts and measured two inches up to the locknut, so that both struts would be at the same height relative to each other. Then tighten the lower locknut. Jack up the control arm and install the strut bolt, complete torqueing the top nuts. You are done. Put the wheels back on and go about adjusting your ride height.
Slamola!
- s13 coil overs
- s14 modified knuckles
- s14 adjustable lower control arms
- Powered by max s14 extended inner tie rods
- Moog s14 outer tie rods
- using q45 rotors
- dual piston calipers. Z31 rear