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quote:
Originally posted by DOES 200:
Thanks Tom for the gloss autozone 95004, they look nice. If I go with the autozone and get those detomoso off, I will get da wifes bathroom scale out and measure the pressure of deto and autozone by using the scale on my 4 post lift to compress them.


I could NOT compress the Auto Zone by hand (weight) but the rear deck SEEMS nicely balanced (1973 with the small "Ferrari 308 spoiler"). When I removed my worn original styruts, I could compress them using my weight...~183 pounds
Here we go again!

I have the NAPA deck shocks, installed this spring because of a failure of the OEM shocks.

I have been concerned with the pressure required to close the deck. The pistons are pointing down. The shock pressure increases as the closing of the deck gets closer to the latch. I also have an issue with the deck lid not fully opening, by about an inch. I believe it is due to the "slop" created by the oblong mounting holes, both ends. I even fabricated spacers to try to solve the issue. Though I am concerned mostly about the pressure.

I contacted Wilkinson. Bill was very nice and explained the NAPA shocks create the most pressure in the closed position. He said they have seen numerous deck lids damaged (bent) and deck lid hinges and pins warped with these shocks due the pressure exerted by the NAPA (Belcamp & Omni shocks). The shock (NAPA style)pressure is maxed in the closed position, exerting a constant amount of pressure on the deck lid.

Bill advised their replacemnt shock has the correct pressure and it is maxed in the open position. He also said he it will not make any difference on the NAPA shocks to have the piston up or down, same pressure.

Bill said a new deck lid is $5,400.00 !

I do not see any reason to screw around trying to save $45-50 and risk damage. I don't believe he would set any sales records for a pair of shocks costing about $90.00. I felt his advice was sincere. His also comes with the hardware.

We all like to save money but the possible consequences do not seem to be worth the risk. I will let you know how they work after installation.

IndyDave
Last edited by indydave
quote:
Bill advised their replacemnt shock has the correct pressure and it is maxed in the open position. He also said he it will not make any difference on the NAPA shocks to have the piston up or down, same pressure.



While I would not disagree that the vendors have likely done their homework/trials to come up with the correct pressure shock, I fail to see how a gas shock that is designed to hold the decklid open can be at max pressure in it's extended form. As the piston is forced back in the shock the gas will be under higher pressure i.e. in the closed position. Using the same deckild/body mounting points (bending moments) then nothing much has changed other than you have a gas strut that a vendor is standing behind to be of corrrect pressure for your application.

Did they ask you if you had a wing or fiberglass/CF decklid? All of these factors would affect the recommended pressure shock to use.
Bill advised their replacemnt shock has the correct pressure and it is maxed in the open position. He also said he it will not make any difference on the NAPA shocks to have the piston up or down, same pressure.

The aim of mounting the shock with the piston down is to maintain the shock's seal in good condition. He correctly stated that it will have no effect on the pressure.
Interesting perspectives. The other week I ended up purchasing the Mighty-Lift D95004 that I show in my posts above (maybe same as NAPA?). I purchased these because I felt the Wilkenson style (Detomoso) struts felt pretty stiff. However, I admit the Detomaso ones are more stiff with the hood open and real soft in the spot to latch the hood when shut (I thought maybe that was just due to hood leverage, but maybe not). I asked Wilkenson about those Detomaso struts about a year ago, and he said he has never had any problem with those Detomaso struts damaging any hood. So, I may end up leaving the Detomaso on the car in the end, now that I see these posts. Looking at both struts however, the Detomaso are larger diameter though, so I was assuming stronger.

In regards to car with wing or not, I don't think it should make any difference, since the same strut pressure is on the hood when you are closing the hood with our without wing (without wing you just need more hand pressure on the hood). Wilkinson only sells the one same set strength Detomaso for wing or no wing.

Maybe someday someone will measure some of these strut options on a scale and report back the extended and contracted pressures. If I had mine out of the car I could measure them with my 4 post lift to contract them and a bathroom scale.
For what its worth, you can actually check what you've got in terms of upward pressure. Take a deck-shock off, set it up in a press with a bathroom scales under the shock. If when you press the extended shaft down an inch and the pressure is over 110lbs, your decklid and hinges are at risk of bending. Most of the vendors will not sell a shock with over 110 lbs of pressure- and remember you got two of those suckers! My vendor-shocks for non-winged cars are 70 lbs each. For those with big heavy wings on their decklids, no deck-shocks will reliably hold it open. I like one vendor's slotted tube that is as long as the extended shock shaft, fits around the shaft, touches the deck on one end & the shock body on the other, so acts like a prop, without having to carry a mop handle around. Only one is needed. And it fits in the glove box when you're moving.
quote:
I like one vendor's slotted tube that is as long as the extended shock shaft, fits around the shaft, touches the deck on one end & the shock body on the other, so acts like a prop, without having to carry a mop handle around. Only one is needed. And it fits in the glove box when you're moving.

I made mine out of PVC tubing. I just ground a slot in it to fit snugly over the shock shaft.
Jeff
This post made me do some research. I have kept track of every single part I have replaced - and I have replaced most of this car over the past 20 years.

I could not find a single notation of decklid struts. I looked at old pics of the car from when I first got it all the way up to the latest pics from last week. And yup, they are same old original struts in every pic.

In 20 years they have never failed. Not once. Even with a big delta wing, it opens with simple push of the button and effortlessly pops open almost by itself. And it stay like that as long as I leave it, sometimes for days.

Closing it is also a snap. It glides closed with a very light pressure and clicks shut.

I don't even know what kind of struts they are. Are these magical Detomaso struts? Am I just lucky? Or what?
Well, here is the first measurement on a brand, if anyone wants to add more brands. I measured one strut using my 4 post lift as a press with a scale under it.

Mighty-Lift D95004:
1" compressed = 96 lb
4" compressed = 105 lb
6" combressed = 108 lb

I did not put the Mighty-Lift on my car yet. I still have the Detomaso sold by many on my car, below is a link to the one from Wilkenson. I would be real interested in the pressure of these Detomaso struts.
http://www.panterapartsusa.com...l.cgi?prod_id=18126A


To continue with this post by adding more pressure measurements of other struts, I just measured the Detomaso 18126A brand from Wilkinson and here are the pressure specs:

1/2 to 1" compressed = 120 lb (this is what it took to make it start to compress).
2" to full compression gradually increased from the 120 to 160 near full compression.
Last edited by does200

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