Hood damper (lift, prop)

Andy,

Thanks again for the detail and sectional reply... When I open my hood, I have to lift it a little then the shocks will take over but they do NOT push the hood all the way up. I have to push it up for the last few inches and it seems like they even fight with me because it is like I am pushing the hood through thick mud! Then the hood will stay put nicely and on the way down I can just push it down easily. At the moment, I have a feeling that my shocks may be somewhat defective. I will write the company and see what they say.

As for the new shock, I will wait for the company to reply back first but if they will do nothing I may go for the 19.72" one and perhaps 40 lb ones.

As for the term you coin "pressure curve", I do understand what you mean and I think in theory the shock should start off with maximum force, then the gas expands a little thus reducing the force somewhat all the way to the end of the stroke. More to the point is the "angle of attack" which play the major role on how the effective force is distributed throughout the cycle. If you were to play with the truck, you will see exactly what I mean.

Remember the hole you pointed out at first, it's the one that is very close to the hinge. I was thinking of the short shock that might work but again I am afraid of the flex force that may later deform the hood or frame structures. This already happened with my 4Runner and I had to add the braces to strengthen the hood's edges.

I will report back when I hear from Circuits Sport.

Have a nice day,

Tanasit

 

My current ones' length is 17 inches and it opens just enough so I can go wider, thus longer shocks. I figure no more than 2 inches longer will translate into 5 inches or so wider at the lip of the hood. I am tempted to try out a few sets from local auto part stores too. I don't think they rated the force but only for what cars, so I have to go by the length and stroke only.

 

2009 2010 2011 2012 Toyota Prius XW30 Silver Carbon Fiber Hood Damper Set d3n5 | eBay

Andy,

I decided on the 18.2" from McMaster at 50 lbs. each. I can't go beyond the 19" length because the hood will max out.

I just saw the set above and looked at the brackets design with interest. My shaft is M6 though.
Then I was looking at the gas spring with remote release and couldn't help thinking "what if".... a remotes release combined with a bypass trunk unlock switch, you will get an auto-open trunk.

 

Andy,

I chose the 50lbs/18.18" ones but once arrived, they are M8 not M6 as the others! I had to order the M8 ball sockets which arrived the very next day.
After I installed the 50lbs ones, even at 18.18" the hood opened almost at 90 degree and rose up rather fast!
I then decided to get the 40lbs/17.13" ones that come with the ball links and again I ordered at 3pm and they arrived the next day afternoon.
With this set the hood opened up to about the same as the stock rod but at the end of the stroke, it sped up a little which is fine by me.
I later checked the force of the 50lbs one and it read around 64 lbs! I was thinking of getting the 30lbs ones but then I remember in winter time how much less power they will be, so I will settle down with this set.
No bracket relocation required.
I thought about getting the quick-release connector, in case I want to change the opening width but again I may never need that...

 

Since the setup at 2x50lbs shock gives me a rather rapid rise at the end, I thought I should try replacing one of them with my old Circuit sport which I tested at 30lbs. I was hoping that the new combine force of 80 lbs will be better. After I removed one 50lbs shock, I tested it and just like you said, it had enough force to push the hood up with authority and hold it too. But I still noticed a fast rise at the end, so I put a CS 30lbs to pair with. At this point you may ask why do I want to add more force when one 50lbs shock is powerful enough.
When I tested the force by pushing it straight down onto the bathroom scale, I noticed that the CS shock moved much slower on the return stroke that the SUSPA Grand Rapids from McMASTER. I also think that McMASTER underrated the shock force somewhat. Anyway after I paired up the 30lbs CS and the 50lbs SUSPA, the upward motion becomes slower and more gentle at the end. After I checked the trunk, I think my combo is smoother and not as forceful at the end (but again the truck is much heavier).

I have another plan in mind and have all the parts to go ahead??

 

When I took mine for the services, I put a note saying that it has a gas lift please open the hood slowly, otherwise they may damage something! And yes still smile every time I pop up the hood.

 

It depends on the structure and the brackets/base combination. All factory installed should have no issues but after market may. As for the Prius V, which came without one so people has to do some modifications. I already tried the single shock with unhappy result, so I used two. Note that with my setup, 25 lbs is too weak and 50 lbs is too strong, so I mixed them up. I tested when is's very cold and if it holds the hood then it should work fine all year round. The ones that have just enough lift to hold in summer time, may not have enough strength to hold the hood in winter. When possible, use 2.

 

Plus easy to work with without the rod in the way.