ANMVQ

iTrader: (13)

Agree with the above I had HR's and couldnt go anywhere with scrapping. I wanted a mild drop so went Swifts. at least for me and the X sedans the drop seems perfect.

Rochester

iTrader: (9)

That matches the general opinion of what I had in my head, except I thought Eibach was more severe than Swift. Either way, that's a fair round-up.

I think it's a good good candidate for a stickied DIY. Thanks, Brad. I'd also say let it ride until it quiets down and decide then. It's relevant enough for Sedan members to find here...

...like Mike, for example. Where's Mike? Hey Mikey, look down and to your left.

Rochester

iTrader: (9)

I nominate you, jgronline. Want to do this before your drop?

To repeat what I did:

• Assuming proper tire pressure...
• Assuming an empty trunk and back-seat...
• Assuming a half-tank of gas (because that's what I had at the time)...
• Find a flat and smooth surface parking lot, and target what seem to be level parking spots.
• Take floor-to-fender measurements accurate to 1/16" of all four corners.
• Turn the car around in the exact same spot and do it all over again.
• Rinse and repeat for two more parking spots.

jgronline

iTrader: (3)

Sure but it might be a while. I've had the springs in my garage for a couple of months and I haven't been able to find a free weekend to install it yet.

PeterChau

This is currently mine after being dropped on Eibach's. I also have the saggy back

blnewt

iTrader: (13)

Well, now you know what to do

botlfed98

iTrader: (11)

yep HRs were horrible. I added the Energy Suspension bushing to bring up the rear and the ride was still just to rough for me. I'm on Swifts now which seem to be much better but far from that stock ride

Rochester

iTrader: (9)

Indeed. Lots of story-telling in my post, but at the end of it all you know exactly the 3/8" bushings to purchase, and exactly how to customize the upper-seats so that they fit.

jgronline

iTrader: (3)

Maybe instead of "saggy bum", the post should be "How to increase rake angle" because your solution basically raises the rear and it is independent of wheels, springs, etc.

Rochester

iTrader: (9)

Nobody used the word "saggy" except PeterChau. So maybe I'll just leave it the way it is, as v2.0 continuity with the G35Driver thread.

Now get out there with your ruler and collect sample data of a 6MT Sedan on OEM springs.

Should take you all of 20 minutes for 24 measurements. You know, for posterity (no pun).

Furlow

Epic post, Rochester.

lobuzz311

iTrader: (6)

This thread (and your build thread, Rochester) are very interesting to me, as I plan on dropping my "new to me" G37S 6MT sedan Swift springs and would VERY much like the drop to be even. Let me rephrase, my OCD would VERY VERY much like the drop to be even.

So I went out and took some measurements in my garage & driveway, both of which I tested with a long level and they are both dead flat. I took measurements with an industrial grade laser measure, so it's accurate.

I assumed the tire pressures were fine until I was 2/3 of the way done with measuring, as I just picked up the car from the dealer a week ago and they set up the wheels / tires. I guess you know what the say about assuming... So 2 wheels at 34psi, one at 32.5, one at 33. I have a compressor line kit arriving Friday, so I can refill and remeasure. Also, I have a full tank of gas more or less, and I wasn't going to burn half a tank just for the measurements... So it's not exactly in line with your methodology, but it's a start...

Anyway, here is what I got:

In garage, facing in:
FR - 28.346
FL - 28.228
RR - 27.717
RL - 27.717

In garage, facing out:
FR - 28.425
FL - 28.150
RR - 27.835
RL - 27.835

In driveway, facing in:
FR - 28.386
FL - 28.425
RR - 27.913
RL - 27.874

In driveway, facing out:
FR - 28.386
FL - 28.346
RR - 27.992
RL - 27.953

jgronline

iTrader: (3)

Another strategy would be to use the stock rear springs and cut the rear strut mount.

DIY: Cutting Rear Springmount aka "the springmount mod" - Page 17 - G35Driver

It would likely give you the same ride as you have with the stock springs and a more predictable rear drop. You can basically figure out the rake you want and then cut the mount accordingly.

Rochester

iTrader: (9)

Well done, man. Very well done.

I'm going to assume FR (front right) means Front Passenger, and so on. If we plug those numbers into the same worksheet, for two flipped locations, we get these results:



...making the OEM setup approximately 28 3/8" front, 27 7/8" in the rear on the RWD 6MT Sedan. With a from-the-factory droopy bum of 0.5". It's just not something that's readily noticeable with the OEM height and tuck. (Obviously, I'm fuzzing the numbers into familiar 1/8" ticks.)

That doesn't mean the car isn't level from the factory... not at all. This is all about perception. By reducing the gap and poking the wheels flush with the fenders, the eye sees a line in the design that fools you in thinking the rear is *lower* than the front. By raising the car 1/2", you eliminate that visual trick, and introduce a gentle rake to how the car sits.

Rochester

iTrader: (9)

If you inspect the top-seats, you'll see they aren't a uniform material of solid rubber. The cone section is much harder, almost feels like plastic. Similarly, on the bottom side, there is a only thin layer of rubber over another harder material just beneath the surface. Clearly there's a double-mold of compound materials here, making it a more complex design than a single mold of rubber. In other words, there's some purpose-driven engineering involved.

So yeah, you could cut the upper seats... but I wouldn't recommend it.