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leadfoot · Posted: Mon Sep 10, 2007 2:34 pm Post subject: Engine shock replacement

Not got one, but want one ? Got one but yours is shot ?
This guide may help you fit an alternative, not saying it is better than the original as I never had one on my car...
This was purchased on ebay for about $60 + shipping...

No, I pulled it apart, Was half expecting to leak hydraulic fluid glad this didn't happen as I did it in the lounge room....
Next I went out and bought two right angle zinc plated steel brackets...
These are 5mm 90deg and have three pre drilled holes in them on each side.
You could use any steel angle you want, these were about $4 each...
I did not use the strut mount or engine mount that came with the shock as I was not mounting it from the strut top and it was for a nissan anyway.

Jack up the car on stands and remove the belly pan...
You'll need a drill, some various sized bits up to M10 size and a dremel burring bit and some protective glasses are a must, bits of steel in the eye are to be avoided at all costs....!!

TOP MOUNT, there are two mount holes near the middle and lower section of the block on the intake side of the block, I think the intake manifold support might have been bolted there at on stage? Lining up the bracket and using the two outer holes the top one will fit with an M8 25mm, the lower hole on the bracket needs to be elongated about 5mm for the other M8 25mm bolt to fit.

LOWER MOUNT, On the lower cross member there is a flat section that run along the middle of the engine bay before at the edge past the oil pan it takes a 15 deg upwards turn.
Place your second angle with one side edge against this 15 deg turn so that the body of the angle plate sits flat against the cross member.

Here's where things get tricky, as all this is done in situ, getting the holes drilled in the right place.
Drill a pilot hole through the side of the cross member in the centre of the outer hole where the shock will mount. Use a 2mm bit.
Next place the bracket inside the cross member and align the holes, notice it will be offset by the thickness of the metal on the top of the cross member, take this into account as you will need to offset your pilot holes by this much when drilling through the top of the member. i.e 2/3mm to the back of the car. Use the two outer holes as your pilot hole guides.
Next enlarge the holes so that the top holes are good for M8's and the side hole is an M10.
Place the side bolt from inside the cross member out and the top bolts top down. Secure with lock washers and nuts.

ATTACHING THE SHOCK, On the top mount use the middle bolt hole and an M10 bolt and finger tight up the nut, notice how the shock body is placed at the lower end, this is with good reason.
Get back under the car and roughly line up the lower heim joint with the protruding bolt. If it doesn't line up don't worry, there is a lock nut on the base of the lower heim joint, back this off and you will be able to rotate the heim joint out a few mm... you ca see from the top photo the joint is actually about 40mm long so you have over 10mm of play safely to work with.
Align the bolt, tighten up the nuts and tightien up the top mount nuts. You are done.

As a note, the shock has both up and down movements dampened, it also via the bottom fittings allows pre load to be applied to the shock, I did not wanted minimal pre load and screwed in the round fitting only enough to engage the dampers and tightened down the lock nut. You may want more pre load for your setup. This will however reduce the overall length of the shock and should be taken into consideration and I would consider mounting the shock and doing a test placement before drilling holes in the cross member.
Happy motoring...
Leadfoot
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1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

endwrench · Joined: 07 Dec 2002 Posts: 1631 Location: Victor, Montana

Nice write up! So how did it work out for you? Get rid of the vibration you were after?

Todd
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'79 924NA. Rebuilt 9.5:1, MSDS header, Mega Squirt Injection, MJLJ-EDIS Ignition, 1.6L Whipple Charger and Intercooler, 10lbs Boost, 944 Trans, Custom HD Clutch.
"simsport" said....superchargers are better than turbos its official!....

leadfoot · Posted: Wed Sep 12, 2007 8:52 am Post subject:

Definitely runs smoother. very happy with the result...
Leadfoot
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

Anybody know how long of a damper is needed on a 924?
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1980 924 NA
1982 931

leadfoot · Posted: Fri Sep 02, 2011 6:22 pm Post subject:

there common as muck on ebay, here's an example, just ask them for the dimensions, If you look at the first photo there is a standard biro as reference of the size, all up think it's around the 200/250mm
cheers
Stu
http://www.ebay.com.au/itm/KLS-NISSAN-Z33-Z-350Z-ENGINE-DAMPER-Kit-VQ35-QUALITY-/130428106335?pt=AU_Car_Parts_Accessories&hash=item1e5e1ef65f
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

I've often wondered about the engine vibration damper. I have had 14 different 924/931 pass through my hands, and not a single one of them has had the vibration damper. Was it an option? Was it only on ROW cars? What's odd is that the US version of PET indicates that it is only for the NA. However, the ROW version of PET doesn't show it for the 924, and has a different part number (931 375 901 00) listed as "installation set vibration damper for subsequent installation".

This is an interesting project. I'm interested to see how bad the vibrations are in the Club Sport in which I'll be using the Vibratechnics race mounts. Maybe the vibration damper would help on that kind of setup...
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erstwhile owner of just about every 924 variant ever made

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

yea, I found a ton of them on ebay for a bunch of different sizes. My NA has one, it's not shot but the rubber mounts have disintegrated and I'm sure it's not as solid as it once was considering it is 31 years old.

Most of the ads don't give lengths only car models, so some research is necessary.
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1980 924 NA
1982 931

leadfoot · Posted: Sat Sep 10, 2011 8:59 pm Post subject:

Dan my issue stemmed around having a supercharger hangin off the front side of the motor and the extra torque it produced at lower rpms. I used to get alot of vibration through the accelerator pedal of all things and some twisting of the motor in a diagonal fashion. After install i hardly felt a thing and i was convinced that gear shifts were smoother.
Atm i had an issue with clearance to the brake booster to my intake manifold. How I alleviated this was to remove the solid mount on the left side and filled it with poly urethane so that it didn't sag as much and also trimmed a few mm off the mount so that i could raise it but at the same time shim it back out if needed if the urethane trick works.
Still haven't taken the car for it's break in, but was also thinking of stiffening up the gearbox mounts as well.
Stu
_________________
1981 ROW 924 Turbo -
carbon fiber GT mish mash
LS1 conversion in progress...

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

After reading this post, I realized that I have one of the original vibration damper brackets sitting on my assembly bench. Wonder if I have more floating around in the parts bin?!
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erstwhile owner of just about every 924 variant ever made

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW