Thread: Lifted P38 on air - questions

Definitely a panhard mod candidate!

Hey Keithy. When you get a chance could you measure the distance from the base of the lower piston to the base of the top part (well top when it's mounted) when they are likely to touch.

Assuming it can be done, and not too hard, with your retired gen 3 you likely still have. But sweet if it's in the too hard basket.

Originally Posted by pbrown

Hey Keithy. When you get a chance could you measure the distance from the base of the lower piston to the base of the top part (well top when it's mounted) when they are likely to touch.

Assuming it can be done, and not too hard, with your retired gen 3 you likely still have. But sweet if it's in the too hard basket.

That's a good idea. I wouldn't mind seeing a photo of that.

Great timing haha! I'm seconds away from bed and I fly back to work at 5:30 tomorrow morning! Ill race into the garage now and see if I can make my dud Gen III do some dancing!

From where the bottom piston sits on the axle to the bit where the top plate sits against the chassis... They will hit at 16.3cm.

When the car is on the bumpstops with no air, the bag sits at 16.5cm at the back and 17 at the front of the rear piston. Hope that makes sense. .. I.e, the rotation of the diff tips the piston a tad forward.

But; if your going to angle the bottom piston any further forward than 11mm you need to add a 5mm extension to your bumpstops. Hopefully that makes sense. .. hopefully a photo brings clarity - cause the maduri sure isn't

You beat me to it!

I got 165mm before the piston touches the top in a straight up-n-down compression.

Peter, I took pics of the inside of a Gen III so you get an idea of the structure of the top hat, and bag and piston beside each other at the point they would make contact (which is just below the upper crimp ring). Could you put them up as I'm not near the laptop!

EDIT:

The measurement was taken from the upper lip of the top hat (only a mm or so below where the air line enters the hat).

Cheers
Keithy

So 16.3mm is the magic number until they hit. For the rear anyway. So they are pretty close with no spacers then? Like real close if those measurements are right. If so, then the bump stops extensions will need to be almost the same as the spacers. Damn I hope that's not true cause I was really hoping to not extend the bump stops with my 25mm at the centre of the spacers.

Edit: Keith's reply as well now. Wow info overdose. 165mm is the number I'll be keeping a close eye on taking into account the spacers are angled

FYI, the piston is 138mm long, and it meets the upper part of the bag at 6mm below the crimp ring. So if you are measuring while the bag is on the car, measure from 6mm below the crimp ring and 138mm later you should have piston and hat kissing (if the piston is vertical). I couldn't make the piston change angles and compress the spring, so can't offer measurements there.

Cheers
Keithy