Gas Struts for Trunk - Honda Prelude Forum

badahab · 04-08-2008, 05:35 PM

Hey everyone. I recently replaced my trunk spring for gas struts that I found at autozone for about 15 a piece. It works great, I pop the trunk with my remote and it opens all the way up without me helping.

I have a problem though... the strut I found is WAYYYYY TO STRONG. Its so strong that it pushes the trunk up and I can't get a good seal. I had one on each side but I thought it was going to break the latch. With just one on it pushes the lid to one side and causes it to rub. Its so strong that it can easily break 1/8" hardware. I'm using 1/4" hardware with a 3/8" bushing (nylon on one end and steel on the other).

I've seen other people do this and was wondering which struts or "gas springs" that they used. I'm using an arm strong or mighty lift 4417 which was used for an early 80 el Dorado hood. I can't find any specs on it, but I can't compress it by hand. I think a pair of struts in the 20-30 pound range would be about right, but I'm not having any luck finding anything. It would need to be about 8.25" closed from the center of each hole... and about 12" or 12.5" open. I've attached a couple of pics to see what I did.

Thanks for any help or pointers guys.

-Sean

btw that trunk spring was impossible to get out by myself... I ended up using bolt cutters... which was kinda scary.

Ludatic · 04-08-2008, 06:50 PM

I've been looking into doing this but I'm still trying to get all the proper measurements (weight especially) before going out and purchasing the gas springs. If yours were made to hold up a hood, then that's definately overkill.

They do sell gas springs that are adjustable (one time). Basically you release the gas that's inside and it will drop the strength, of course if you release too much the you're screwed lol.

What reason did you choose to do this mod anyway? Aftermarket speakers rubbing against old torsion bars?

badahab · 04-09-2008, 07:24 PM

Speakers were part of it. I'm planing on doing an amp rack mounted to the underside of the rear deck, so it helped with that too. Also its just kinda neat.

badahab · 04-10-2008, 09:16 PM

So I found this place called spdhardware.com has anyone used them before?

They have exactly what I need, but I'm not totally sure how many pounds of force I need.
http://www.spdhardware.com/catalog/list.asp?id={FD677C08-6417-4A4C-9551-C52741324413}

-Sean

Ludatic · 04-11-2008, 03:02 PM

get a tension meter and find out how much your trunk weighs from the lift point and you're set

Brash22 · 04-13-2008, 04:06 AM

There's a post on here somewhere where I outlined my setup. From memory (you'll have to find it, I know it's here somewhere, but I can't find it!) my gas struts were 300mm (12 in) long with a 100mm travel, and a pressure of 30kg each.

Brash22 · 04-14-2008, 09:46 PM

Ok, maybe I didn't post the details up here.

I fixed the brackets on using pop rivets because it was what I had. Tek screws would work as well, or if you feel particularly crafty a welder would probably be the most permanant way. I've also used some double sided tape between the bracket and car to act as a bit of noise and vibration isolation; probably overkill but oh well.

The strut body is 200mm (about 8 inches) and the extended length is about 300mm (12 inches) and they're charged to 30kg pressure each.

My trunk has the OEM spoiler, and with this setup the lid fires up when I hit the release lever inside, but isn't so stiff that my gf (whose only 4'10'' tall) can't close it by herself.

I also used eye head struts and nuts and bolts because it was what I had access to, a ball stud end would probably work better, and would allow bit better servicability.

Make sure you mount the struts with the body at the engine end of the car, as the hydraulic fluid inside them will drain to the seal at the end of the body naturally when they're compressed, and extend the strut's life.

My setup has been there for nearly two years, and the only problem I've had is that I've broken a couple of rivets and had to re-mount the bracket on the LHS, but other than that, I'm still happy with it. If there's any other questions don't hesitate to ask mate.

pIOUs · 04-28-2008, 05:04 PM

I skipped the bracket. The geometry I was limited to means you have to help it fully extend that last inch. It pops up by itself when I release the latch...with a spoiler and amp attached to trunk.

natemanas · 04-28-2008, 06:30 PM

I've always wanted to do this.. and to the hood too.

pIOUs · 04-28-2008, 06:52 PM

Quote:

Originally Posted by badahab

Speakers were part of it. I'm planing on doing an amp rack mounted to the underside of the rear deck, so it helped with that too. Also its just kinda neat.

I did an amp rack like that too, but be careful. The heat sinks aren't designed to be efficient upside down. Mine drives modest 6x9s so no worries for me.