P38 Suspension Lift Guide

Quote:

---

Originally Posted by finallyrangie

height sensors are underway,

made my own adjusters from some 10mm stainless tube, 1.5mm wall thickness so fits nicely over the rod the height sensors are made from, then welded an M6 nut on each end. cut and thread the ends to give adjustment.

This is where the questions start

the rear I have extended by 20mm on each leg as some of the original kits, the front ones I have fitted a fixed 20mm extention to the short arm and added an adjuster to the other leg, the question is how much longer does that other leg need to be, it seems to me that the extension must be less than the back as the arms are shorter so there will be more angular change per mm of extra length.

so how much longer does the other leg on the the front sensor need to be?


I am really hoping that all makes sense, it did in my head when I was typing it

---

I made all my arms 10mm longer, so top and bottom arm. Reason being is that on full droop they are similiar to +20mm only on the bottom. But at full compression they aren't much different than stock, where only extending the bottom one can make the sensor rotate further and even the arms can hit the body I believe.

The attached sketch is not to scale but shows what I mean. My arms are equivalent to the two 215mm arms, and only extending the bottom one is the 230mm and 200mm arm drawing.

But there are people who only extended the bottom arms so don't take what I did as gospel ha ha.

Off memory the height sensors arms are mounted about half way up the arm, so the +20mm extra sensor arms length equates to almost 40mm more extension at the end of the suspension arm. This is all off memory so excuse if the mounts aren't half way

Sorry the quality got messed up because it was telling me invalid png file, when the file was a pdf damn it. Here is the dropbox link to the better quality pdf.

https://www.dropbox.com/sh/n37slureo...1KK5a'dl=0

I extended only the lower arms front and rear on my height sensors. 23mm on the front and 40mm rear from memory. I had dramas where the rear arms would touch the chassis when the rear bags were deflated - fixed by adding 10mm of soft padding to my bump stop extensions. The fronts threw up an EAS Fault with deflated bags, not due to contact but rather the sensors just going out of range. Fixed by adding 5mm to the front bump stop extensions.

With the gain in wheel travel due to the longer shocks it was an easy fix, and the vehicle rode level without any need for re-calibration once I lifted.

Cheers
Keithy

I may have actually added 15mm to all arms. I can measure if need be.

Thanks for all the help with the sensor arm lengths.

bit of reworking and I now have the rears at plus 20mm on each arm and fully adjustable and the fronts at plus 10mm on each arm with the top one adjustable.

next question (I did promise many) is regarding bump stops, if I add to the axle pad how have other people attached the extension blocks to the axle, if glueing extra length onto the bump stops, what kind of glue do you use?

thanks again for all your help people

I used cable tie glue ha ha. Seriously I put solid rubber blocks (the same height as my blocks) and grooved them to put cable ties around the axle.

A dodgy temp job before I put a flexible glue on there but it has stayed that way :)

As far as glue, I am not sure but I do know loctite make some really strong impact resistant glue. I can find the number out for you if no one else suggests what to use.

I can get ms1 windscreen adhesive from work and that has so far stuck everything to everything, but I know nothing about glue at all so I don't want to break anything if the extensions fall off.

I like the cable tie idea, belt and braces approach every time if I get the option.

Yeah mine are cable tied to the pads! I had all intention to make a custom bump stop but haven't had the chance to do it!

Nearly 2yrs my P38 has been lifted and they are still attached to the axle pads! I will eventually weld a 50x50 box section to the diff (just a few tacks).

Cheers
Keithy

I did some research today guys, perhaps common knowledge to a few of you, and the same for me, but for the purposes of those who are unaware (in QLD at least) you can legally use our lift kits on the road, and provided your insurance company is happy to insure you, it's legal - without any engineering required. You don't even need to tell the transport department. The catch is that the spacers need to be fabricated from (basically steel) and approved material, and welded/fabricated to ADR welding standards.

I did some more digging today too, see the tyre thread (I'm not happy)...

Cheers
Keithy

Keith, most insurance companies are ok with it too as long as you don't exceed a lift of more than 50mm (as I found out recently when shopping around for insurance)

Gary