Rear ride height problem after installing coilovers help!!

[JMortensen]

If you pulled it back apart and sectioned (agreed not exactly a 10 minute job), you wouldn't need to purchase anything, just cut and weld.

 

Jon

[Modern Motorsports Ltd]

Juan, I got your email so naturally came here to follow your reference. It has been a very busy week, Moser order just unpacking for the beefy R230 crowd Some have received theirs previously

 

Available strut travel IS NOT your tire to fender gap. Perhaps read some searched threads on '280Z struts in 240' , strut travel is ability for strut to compress or extend from present position. Assuming tire clearance for travel the strut MUST have adequate travel depending on all inputs of your suspension.

 

Please measure strut travel as noted above, you'll understand my post more and see what your options are.

[Guest Looking for apt in Alb Ny]

I have alot of strut travel available.

 

Am I suppose to use 8 inch springs rather than 10 ?

 

I cannot adjust my collar any lower than it is.

 

 

thanks Juan

[CruxGNZ]

.Am I suppose to use 8 inch springs rather than 10 ?

 

Don't see why not. Hyperco lists a 8 inch 225 p/i spring. Give it a shot, doesn't hurt to try this before having to cut and weld again.

 

!M!

[Guest Looking for apt in Alb Ny]

Thanks Mat for your post. Im looking into this right now. Ill let you guys know what happens.

 

Juan

[Modern Motorsports Ltd]

Thanks Mat for your post. Im looking into this right now. Ill let you guys know what happens.

 

Juan

 

Guys, Juan said he's 3.6" higher than where he wants to be. Why bother just swapping from 10's to 8's? That's 2"....nowhere near 3.6". Their may be a conflict sitting their we'll expose. Did you read some other searched threads I referenced?

 

Juan 'lots' isn't anything to base a recommendation on, I can't provide further assistance without definitive answers, I'm sure you can understand this. Measure up as requested and I'll comment further.

[CruxGNZ]

Guys, Juan said he's 3.6" higher than where he wants to be. Why bother just swapping from 10's to 8's? That's 2"....nowhere near 3.6". Their may be a conflict sitting their we'll expose.

 

Ross, he said:

I have not shortened my struts but my rear sits about 3.6 inches high and that's with the adjustable collar all the way down

I was assuming (not the best thing to do) that this was the distance from the top of the wheel to the fender. If he went with 8" springs, reducing the gap by 2" that would leave a 1.6" fender to top of the wheel gap. With his perch screwed all the way down, he can raise it to match the front.

 

Didn't mean to give bad advice. Just seeing as how he didn't like the aspect of having to weld again, I offered the advice in my last post.

 

As for strut travel, well, you do have a point there.

 

!M!

[katman]

I have to second Ross's concern about strut (shock) travel. I wish I had a buck for every lowered street car of ITS racer that I've consulted on that had some goofy handling problem that in the end was caused by the shock bottoming out or extending to it's limit. In ITS I usually recommend 2.5 inches of bump and 2 inches of rebound to stay out of trouble, so on softer street springs you'd want even more. Bottom line, after you get your ride height where you want it check where your shock relative to it's available travel.

[Guest Looking for apt in Alb Ny]

All I can say is from what I currently have setup I can better determine what I need to do. I believe it would be lowering my welded perches by 4 inches in the rear and front. My collars are all the way down and its not nearly low enough. I have plenty of strut travel so this is probably my best choice.

 

My 240z has 280z tokico 5 way adjustable shocks on all corners, 280z suspension, 10 inch springs. 200 front and 225 rear.

 

My perch is on so that my collar sleeve is one inch below the top pf the strut tube. I think that is my problem. It should be much lower than that. At least 5 inches. Maybe it is because I'm using 280z tubes in my 240z. I don't know.

 

Ill figure something out when I get the energy.

 

Thank you Juan

[JMortensen]

One last comment Juan, because it sounds like you're getting fed up with too much advice. If you are going to take the car down 3.6" by moving the spring perches, you are going to lose 3.6" of available travel. I think that equates to about 2.5" of actual strut travel. IIRC the Z has 7 inches of travel at the wheel, and figure about 5 or 5.5" at the strut with a bumpstop in place. That means that IF you have 4 inches of travel available at the strut right now with the weight of the vehicle on the suspension, that you would be left with only 1.5" at the strut or 2" at the wheel after moving the perch down.

 

This is all THEORETICAL, but maybe it will help to explain why Ross was trying to pin down where the strut is in its travel at rest.

 

I'd love to help you more but it sounds like you've had enough...

 

Jon

[Modern Motorsports Ltd]

Juan, it's unfortunate your 280Z struts aren't giving you your desired ride height at present in your 240Z as presently installed. Let's try again to reduce this frustration for you and get you a solution. 6 days back I asked what your strut travel available is with no response, all others in this thread have echoed this thought in one way. Without this I can't give you a solution as you've requested here and by email. This is truly key to knowing what is your optimal solution, for example if you were to:

 

I believe it would be lowering my welded perches by 4 inches in the rear and front. My collars are all the way down and its not nearly low enough. I have plenty of strut travel so this is probably my best choice......

 

We know your present base of threaded tube is 5" below top of strut tube, you've proposed lowering them another 4" or up to 5" additional in your posts for 9-10" total. This would give you maximum adjustment of lowering your 10" springs down to about 9.5" below top of strut tube, and 1/2" of spring above your gland nut (allowing 1/2" for adjusting nut)........essentially jacked up cars unloaded with perhaps 1/2" spring travel taken by bumpstop going to full compression when jack is lowered?!! Zero travel, we don't want to see you go thru more frustration hence our sincere questions. Now do you see why this available travel is essential to have your actual travel available known to proceed?

 

I sent you more detail in a PM to aid getting you back in the saddle

[Guest Steve-Z]

Juan

 

Here's what I wrote to Tickwon on March 24 in a thread called "Coilover Question" in this forum:

 

I might be repeating this, but I think the basic concept for placing the threaded aluminum tube on the strut is that you want some adjustment on both is sides of the final lower spring seat. But getting to that final position is the trick. I think you need to:

1) set the ride height

2) make sure you have enough suspension travel at his ride ht. and shorten the strut to gain enough suspension travel at the desired ride ht.

3) then you can locate the threaded tube so you have some adjustment on either side of the lower spring seat.

 

What I did for a friend of mine running a 510 race car with a shortened strut is to locate the strut shortening weld underneath the welded-on lower threaded tube perch. then I welded on a small tube at the top of where the threaded tube stops, so there wouldn't be much slop between the threaded tube and the strut tube with spacer. He already knew what the ride height would be and how long he wanted the strut, to give him enough suspension travel, so we didn't have to go thru that exercise.

 

I'm agreeing with what Ross C is saying.

 

Hope this helps Steve-Z (Steve Belsley)

[Guest Looking for apt in Alb Ny]

my strut has just over 5 inches of suspension travel when it is jack off the ground when it is grounded I have 3 inches of suspension travel. this is before the top flat spring plate hits the top of the strut tube. I have bump stops that are about 1.5 inches.

 

I think the way to do this is to section my rear strut tubes. I have the 280z rear strut with almost 3 inch spacers. I can easily gain the ride height I need .

 

so is sectioning the only way this can be done? I cant think of any other way. again my whole intention was to avoid sectioning

 

I'm thankful for the help on this.I'm curious what my solution is still to do. I guess its sectioning correct? I don't see any other way of getting this lowered correctly.

 

 

also I don't mean to put my headache on anybody else. just thanks for the help.

Juan

[Guest JAMIE T]

I'm baffled. I've set-up my coilovers with no issues. I made my set-up from stock car sleeves and nuts and Ground Control springs I got from a buddy of mine. I have 5 inch sleeves, and 10" / 225lb springs in the front and 8" /300lb srpings in the rear. Sectioned tubes front and rear. I'm very sure I won't have a problem with too high ride height.

 

About your issue. I'm not familiar with the 280 strut tubes other than they are larger diameter. It really seems like something in the top mount is causing your trouble. I don't think shorter springs or dropping the threaded sleeve is the answer. I'd look elsewere for your 3.6".

[Guest Looking for apt in Alb Ny]

I am baffled myself as well.

 

I dont know what more I can say. There must not be a solution but to tackle this myself...

 

I have properly installed this setup according to instructions in my springs and coilover package.

 

Juan

[Modern Motorsports Ltd]

Jamie: Juan's got 280struts in his 240 which is quite different from your setup. Others have run Juan's combo with coilovers & unsectioned and been fine, but evidently they were OK with a closer to stock ride height (likely quite near stock comparing to Juan's info) than Juan desires.

 

Juan: "my strut has just over 5 inches of suspension travel when it is jack off the ground when it is grounded I have 3 inches of suspension travel. this is before the top flat spring plate hits the top of the strut tube. I have bump stops that are about 1.5 inches."

 

OK, 'before top flat spring plate hits top of strut tube', I assume means before top spring hat hits top strut mount/strut tower? This was only for your jacked up measurement? or static on the ground? It's only your travel sitting on the ground/car fully set down and rolled (ie. settled, not tires cambered out just down off the jack) that is a relevant reference point. If you have 3" at that point this is near ideal as is for suspension travel...the bump stops we typically slice in 1/2 to 2/3 nicking off the pointed end to allow slighlty more travel until they engage.

 

Either way from your measurements you will have to section to drop towards your goal ride height. As present strut travel is near ideal you would ideally section 3.6" (to achieve 3.6" drop you noted) to have same strut travel after sectioning......however I doubt the struts have spacers that tall to allow such a large section. Juan, the numbers still seem quite odd as even with sectioned 280Z tubes for race 240's one would not be sectioning more than 2 to 2.5" maximum out of their tubes. Perhaps your 3.6" is excessively low and it's more like 2" or 2.5" you're seeking? , as this does fall outside what others have done even for dropped race cars. Keep your control arm angles in mind etc so they don't slope up and inward from excessive drop/that'll be very poor handling.

 

"I have properly installed this setup according to instructions in my springs and coilover package. "

 

Yes, we understand that Juan, noones faulting you in any way here, just trying to help get you going. Sometimes we try new combos and learn new ins and outs. Your desired ride height and 280Z strut in 240 combination are overall unique to date it appears. Your intended drop is obviously beyond a mild drop and I didn't understand this from your email desires sent to me. One comment to me you even noted you may not need coilovers which I interpreted to indicate near stock or mild drop height desired.

 

VERY good references for yourself and others to aid in future avoidance of this would be measuring your present ride height front and rear to common points we can all repeat. Perhaps common points would be the centre point of the inboard control arm pivots front and rear? This would be a great FAQ type piece I don't believe anyone has ever done? ie. some believe they only want to drop one inch below their present 'stock' height.....but present stock height with aged suspension could already be an inch or more below stock height leading towards an actual 2"+ drop from OEM and therefore sectioning would be easier to foresee. FWIW, very few actually require sectioning on their Z cars with todays typically larger diameter rims and corresponding tires.

[Guest Looking for apt in Alb Ny]

I really really appreciate the help from everyone. I was able to obtain about .6 " more lowering by removing part of the strut insulator. including the inside hard rubber piece. The car was just to jacked up and I had to let the inside piece go. Ill find out if it damages anything the hardway.

 

Yes the Z is almost at stock ride height. I compared it to 2 other Z's from frame to the ground.

 

 

 

3.6 inch is how much fender gap I have before I cut the rubber and metal out of the insulators. You could see pos camber and it wasn't right.I have 3 inches of fender gap now with 225 50 15 tires. Does this sound right?

 

 

 

I can section the rears for sure but then Ill have to do the fronts which makes 280z front struts worthless if you want to section the front.

 

 

Personally I hate 16 inches rims and super large tires. I'm not running a 300 + hp motor where it limits me to tire and wheel selection. my 14's and 15's do just fine and would rather have a lower stance.

 

all and all its not the bad now. I'm running 225 50 15 and I compared it to oem 195 70 15 in height. 1 inch difference and I will have that 1 inch extra wheel gap.

 

I'm not expecting a drastic drop but I cant even hardly lower it than stock. The collar is all the way down and it sat this high in the rear.

 

Maybe I went over board but as this is my first installation experience with coilovers.

 

pictures below before

 

 

 

after from an angle

 

 

here i removrd what I could to obtain some lowering. As Ross suggested thanks

 

after

 

 

 

where the car sits as it does.

 

 

 

 

me and my friend Jon who gave me a hand .

 

[Guest JAMIE T]

So, What is differant about 280 struts compared to 240 struts other than the diameter? Is the tube actually longer? I know the cushion mount is taller on top(or so I've been told). But, what else? I know that If I had not sectioned my struts, I could have still lowered the car as much as I did, I just would not have had any suspension travel.

 

 

Hmm... I did just have a thought. Juan, have you driven the car at all? Also, how did you tighten your suspension? Was it at full droop when all the nuts were tightened? I have seen freshly restored cars(mostly musclecars and Vettes) sit very high after a frame off restoration do to the fact that the suspension was tighted while the suspension was hanging down(like when you jack the car up, and let the suspension sag). Some of the ones I've seen done this way never dropped to the proper ride height. I fixed a Vette by getting the car up enough to get under it but still resting on its tires. I loosened all of the suspension bolts and hopped up and down on the car to settle the suspension and retightened everything while it still rested on it's wheels. The same thing could be accomplished by resting the control arms on jack stands or on a drive on lift.

 

It may not help your problem, but I thought I'd mention it.

[JMortensen]

The 280 tubes are longer.

[Guest JAMIE T]

How did Datsun make-up for that differance and retain ride height and suspension travel? Are the rear strut upper mounting points located higher in the body/wheel well? Are these cars really THAT diferant? This is actually a good thread. Would using 240 struts on a 280 lower the car 3".

 

Are the front struts longer also?