S14DB

diff bolts to what?

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kandyflip445

Have you seen under your car???

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racepar1

Look man I have done more suspension work on my own and my friends 240's than you could imagine so bite be. Yes the diff bolts to the subframe, but the subframe's primary purpose is to hold the suspension to the chasis. If the subframe moves then your shock angles get all screwed up and that is definitely not good. Another argument for the solid bushings is the 240's stock suspension geometry has A LOT of anti-squat in it which makes the car transition to on-throttle oversteer very easily, that's why 240's are so good for drifting. If you want to use the car for track/autocross it is a good idea to dial some of the anti-squat out of the car as that will give the car slightly more rear grip on corner exit. The SPL bushings allow you to do that.

cwtt

Aweseome! Please keep us up to date. I really need to get new subrfame bushings, however my S14 is my DD/beater car so I have no need for metal on metal bushings with all of the added noise that comes with them.

I may just have to hold out for a month to see your results.

DaPCWiz

I have SPL aluminum collars in my daily driver and I drive 100 miles round trip to work and back everyday. I also autocross 8 or more times a year and plan to hit a few track events next year. They aren't harsh at all, def can't complain. You just get a little more noise from the rear at certain RPMs.

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AceInHole

While the function of the subframe is to hold the suspension and rear differential, majority of the subframe's purpose is to absorb vibration through both the driveline and suspension. On S13's, which have no diff bushings, the subframe is the only isolator between the rear mounted driveline and the chassis.

While maintaining consistent geometry is a good thing, the subframe does not (or at least should not, depending on the age of your bushings) move enough to give "messed up shock angles". It really shouldn't "give" at all with solid urethane bushings, but some of the vibration from the rear differential as well as the suspension should be absorbed if not using solid metal mounts.

The rear subframe does indeed mount the driveline. Your rear differential is bolted to the subframe, and it is a part of the driveline.


You can also dial out anti-squat by adjusting the rear upper links. For the most part, my car's rear end has been nearly zero'ed out in terms of fore/aft suspension drift.


Anyways, my statement about driveline shock is more or less having the ability to absorb irregularities in both the road surface as well as from the driveline itself. I'm not sure there was ever an argument about the suspension aspect.

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AceInHole

From subframe spacers to solid aluminum there was a definite increase in noise, although I don't believe it's affected ride quality other than some vibration, which I suppose is less noticeable with 3" exhaust piping. I'm taking my car out to MD for an Autocrossers Inc. event to do some end-of season tweaking as a head start for next season, so I'll have a bit more feedback (4 hr drive each way's worth) next week.

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racepar1

[quote: AceInHole] You can also dial out anti-squat by adjusting the rear upper links. For the most part, my car's rear end has been nearly zero'ed out in terms of fore/aft suspension drift.[quote]

Wait, the RUCAs only adjust camber, the traction arms are for dialing in the camber curve, the toe arms are obviously for toe, and the LCAs locate the rest of the suspension. What arms can you adjust anti-squat with? As I understand anti-squat is determined by where the arms mount to the subframe, so the only way to adjust it is to alter the control arm mounting points on the subframe or change the angle of the subframe itself. I have read several suspension engineering books, several articles on suspension geometry, and talked to quite a few qualified people about 240 suspension in particular and I seriously doubt I missed that. I need clarification.

CoasTek240

Ive already ordered the SPL solids. I figured thatd be the best bet. Im still looking for a urethane bushing kit. I may buy one on ebay, but they come with so many things i dont want (i.e. front tc rod bushings) All i want are the sway bar bushings and the rear link bushings. any suggestions. btw, I am now just painting my subframe instead of powdercoating. I dont have much time. I need to get my car back on the road.
My daily sucks, i need another daily driver.

racepar1

You can ordrer the bushings separately from energy suspension, but be prepared to wait for at least 3 to 6 weeks. If you are in a hurry you would be much better off ordering the whole kit and trying to sell off whatever you don't use.

CoasTek240

well where do you suggest i get this kit?
-dave

2JZGTE

While we're on the topic of solid mounts...I'm currently using the Yanack aluminum steering rack mounts (solid). Goddamn are they nice.

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R35 GT-R, R32 GT-R, Supra, S13, S14, FD3S

ManoNegra

Wonder how they work for a daily? Where did you get them if you don't mind me asking?

2JZGTE

NP man, got them from RHDjapan.com ~ sponsor on this forum.
They are fine for daily but that's just one man's opinion.
My S13 has the alu. sub mounts, welded cage all that so I'm pretty tolerable.
You will notice a significant increase in tracking when hitting uneven street surfaces.
It's not that bad though...
and once you're at the track where they were designed for...
you'll really appreciate the consistency of the steering.

Billy

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R35 GT-R, R32 GT-R, Supra, S13, S14, FD3S

Bushido

man, the time is just ticking by....

and still nobody has replicated the yanack rack bushings...

i'd buy the real thing, but im kinda sticking to a knockoff theme with this car. HA

next up, SPL solid bushings, i've decided not to listen to the people that say they are too harsh for street use. they said the same thing about part shop max coilovers, and i love them on the street.

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B Love

Anyone on here weld the Metal ones to the sub frame? Me and a friend welded some onto a S15 subframe and I havent seen the car since and i know its not running yet. So has anyone tried this on their daily driven car? Also the best way I found to get the bushings out was a torch

Irukandji

Get the SPL subframe bushings. Full aluminum.

JDS Performance

Here is mine for those of you that was intereted

www.NIPerformance.org

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Clearalbino

I just recently installed the SPL aluminum bushings and they feel a little better then bushings with collars. The only problem with bushings with collars is that it compresses the bushings and further destroying rather then helping the situation.

CoasTek240

so i put my subframe back on last night with these bitches installed...
wtf? did my car sag or something? the subframe was off for 2 weeks. Its so hard to get back on. Im thinking of connecting everything as best as i can and then putting the wheels on and lowering it onto the subframe.
any suggestions?
btw, i still havent ordered any engery suspension kit.

statik

I just did mine, I bolted everything to the subframe, all the control arms, uprights, axles, and the diff, torqued it all down, and used a jack to move it all as one unit from the diff, just get a friend to help balance and go slowly. When installing it the fronts will need assistance to move up with the rear, couple of taps with a rubber mallet helped persuade them into position along the way, just dont keep jacking it up because the rears will go in but the fronts will get hung up. I also installed the shocks with the subframe on the car, but not bolted all the way up yet, much easier to do it all at the same time.

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CoasTek240

i just connected all the arms back to the subframe, as well as the diff.
Im thinking of lowering the car and using the weight of the car to push the subframe onto the body.

as of now the subframe sits 1/2" away from the body.
I feel like the body of the car sagged without a subframe on there for 2 weeks.

is this going to be safe?

D1GP

i highly doubt the body sagged. ive had my subframe out for 2 weeks. it was a bitch to get it back up but i made it happen. i would suggest using 2 jacks, one on each side, and have a buddy help. work slow and line everything up as best as you can.

JDS Performance

On our s14 the rear of the car dropped about 1/4" - using the ebay knock off bushings (SPL's old design)
We are on stock suspension which shows the drop better

Is this the problem you are speaking of?

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nissandr1ft

Mine was a bitch also getting back up. I ended up using my main jack under the diff., making sure it was level, and going corner to corner with my factory jack (~1/4" each time). With that technique it went up in about 30 minutes, I tried a few other techniques, and it was by far the easiest.

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JDS Performance

Ok I just read your post agin - your subframe is stuck half way on the car.

I had the same problem - you have to make sure the subframe goes on the car as straight as possable and as level as possable.

the holes are pretty exact - not sure why you removed all the arms and diff for - unless you were changing them out anyways?

I would use a hammer to help it on there too - dont beat anything to death though - It should only be binded on there - not stuck and unmovable.

Take a pry bar and bump the subframe with the frame and the subframe should drop off the binded area - then you can try to guide it on straight and level agin.

This is pretty much a 2 person job - as it a PITA to do it alone - unless you get lucky and hit it the first time.

Also if its binded on there and you try to drop the car down onto the wheels and let the weight of the car push the subframe the rest of the way - you will be prone to breaking a stud or getting it really stuck or bending something in the process!

All 4 bushings have to go onto the studs at the same time and be level as well

Never try to tighten the nuts to make it move up - you will strip or break the stud!!! and you dont want to have to replace them!

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AceInHole

Sorry I missed this, hope I'm not answering this too late. Also, I'm breaking thing down a bit further than I probably should, in case anyone references off of this in the future. As a disclaimer, I'll be the first to admit I could be wrong.... for the most part I haven't gotten a chance to do much datalogging due to the accident my car was in, but it's the general theory behind how my car was set up:

Really, both your RUCA and traction arm will define your camber curve, as they form what would be the upper "A" arm (with the theoretical pivot beyond the motion arc of each arm). What really defines the camber curve is your component motion of the upper ball joints relative to the lower ones. The jist of it can be seen by simplifying the rear suspension by isolating the lower arm and the upper "camber" arm. With suspension travel, you'll have 2 arcs. Each arc is defined by the suspension arm swinging angularly around its respective pivot, where it connects to the chassis/ subframe. The higher the angle, the more lateral travel will result. The difference in lateral travel is what defines the camber curve. Two ways of adjusting the camber curve are through the difference in relative angle (one arm being at a higher relative point of its arc), or through a difference in arm length. Shorter arms will have a higher angular velocity per travel, and thus acheive more lateral motion relative to longer arms. This is one easy way to acheive more camber gain.

Anti squat can be analyzed easily through statics. Basically, when you apply a force straight downward onto a wedge, the wedge surface will want to react with a force normal [perpendicular] to the angled surface. This normal force can be broken up into two forces, one working against your downward force, and one in a direction "away" from the angled surface, parallel to the side opposite the normal force. The same principle applies to the rear suspension.

The rear suspension generally will not travel directly up and down. Like the surface of the wedge, there will be some angle of wheel travel (simplifying things, of course). A variety of factors contribute to this, the first and most blatant being the lower control arm. If the arm is tilted rearward, then as the suspension travels upwards, the wheel will travel "backward". I the arm is tilted forward, the wheel will go forward. The opposite happens when the suspension travels downwards, or when you apply a force to the suspension. Basically, if the arm is tilted towards the rear (the front pivot is higher than the rear), when you apply a force to the wheel trying to make it go forward, there will also be a force trying to push the wheel down. This is the basic cause of anti-squat.

Now, remember how camber curves are affected by arm lengths and angles? This will also apply longitudinally (forwards/ backwards). When the suspension goes through a range of motion, the rear trailing arm will go through its motion circle. This motion having a different lateral component than the lower arm will create a "tilt' in the spindle, which translates into fore/aft (backwards/ forewards) motion of the axle/ wheel. By altering suspension geometry (primarily trailing arm length), you adjust how the spindle rotates to counter-act or add to anti-squat.

Now, it's been said by a lot of drifters that shortening the rear trailing arm gives the car more "bite". My theory applied to this is a scenario where anti-squat is actually being dialed out. On severely lowered cars, the upper arms are at fairly dramatic angles, pointing "up". With the same principle applied to camber curve (shorter arms equat to more component travel), having shorter trailing arms should then result in more rotation of the spindle. As suspension travels down, the trailing arms go "out" from the center of rotation (think: if you hold your arm straight up in the air, and swing it down, i begins to go "out"). This pushes the top of the spindle rearwards, along with the axle. This counteracts some of the antisquat, moving opposite of longitudinal travel of the lower control arm.

Who did you talk to about 240's? I'm betting Tim or Rich (Wiisass or veilside180sx) would agree with my assessment of the rear suspension, not sure who else is out there. Most of it, when applied to all the arms, should be compliant with anything you've read. Suspension is a simple thing that can get complicated by a lot of little things quickly, once you start to analyze it. We all have a tendancy of forgetting a few variables once in a while :P

If I missed anything, or if anyone disagrees with anything I've mentioned, please let me know. I have quite a bit more to learn, myself.

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Dream240

K, gotta revive this old thread.

I am installing nismo subframe bushings. Got the subframe out, knocked out the old bushings pretty easily with my air chisel.

My problem is the two FRONT bushings. The new nismo ones won't go all the way back in!! They get stuck about 1/2" - 3/4" away from going all the way down.

I'm wondering if maybe there's a difference between the two pairs, front and back. I checked the new nismo ones to the old ones before i pulled them and matched up the length as best i could.

Basically I put the two black ones in the back, and the two silver one in the front. Is this right? I hope so, other wise I'm fucked. They don't really tell you one way or the other.

I've been hammering at them like a crazy caveman, and no use. They don't even budge. They look like they're in evenly. So i don't know what the hell to do now. I've also tried the bolt, nut and washer compression trick....just detroyed all the components with no luck.

SOMEONE HELP ME!!

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aznpoopy

i haven't installed these myself so i do not know if they are ordered.

but trying to use the threaded rod trick or straight hammering on something like this can make easy install jobs hard.

assuming the install is correct, you should try a serious balljoint press like this. i used it for the diff bushings in the subframe.

Dream240

Alright, thanks for the quick reply.

I'll get one tomorrow and see if it works. I am actually tempted to buy a 6ton floor press for 90 bucks and watch that thing tackle those bushings. The only trick is getting them into the press.....

Anyone else want to chime in?

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