I have a nova currently with the lucas hydraulic pump & two slave cylinders to lift the roof, and I'd go with the electric linear activators. The lucas system could wake the dead lifting the canopy on a quiet night. In fact when I get round to getting back into rebuilding mine I'll strip the hydraulics out and fit linear actuators myself as I have a flip front/rear to lift out also...I used to have one of those wonderful Nova kit cars, where the roof used to raise on parallel links to get in and out of the car (the sun roof/windscreen and side windows were all part of the fibreglass pod that lifted up and went forward). They did a gas ram option and an electro-hydraulic unit with two rams. It was quite compact, the pump (with it's inbuilt reservoir) was only about the size of two medium paint tins on top of one another, think it was a Lucas item.
I have a nova currently with the lucas hydraulic pump & two slave cylinders to lift the roof, and I'd go with the electric linear activators. The lucas system could wake the dead lifting the canopy on a quiet night. In fact when I get round to getting back into rebuilding mine I'll strip the hydraulics out and fit linear actuators myself as I have a flip front/rear to lift out also...
One other thing you probably want to have some sort of way to make sure the two sides go up at the same rates, or the rams will twist your shell if one becomes dominant potentially cracking windscreens etc. As quite a few nova owners found out...
How big are they ???
How about a convertible roof motor. They're 12v, self contained and most have a override so you could lift the body manually if needed.
Lee
Why not use A hand pump and ram from a truck cab the pumps are manual about 5-6 " square and are remote from the ram, the pump handle is removable, they tilt a truck cab which can weigh as much as a small car and you could pick one up second hand from a truck dismantlers, they are after all made for the very job you want to do.
hi Langy, i can get you a pair of 12v electric screw thread rams for lifting people out of bath/bed,dont know the size as they come in all different but easily lift what you want, how desperate are you ????, and they would be dirt cheap if you can wait a little
Wheelchair tilt and recline actuators steve, 24v dc, very powerful, might have a couple of used ones at work.
Citroen Xantia hydraulic suspension's. You can surely pick up a used banger for cheap
Didn't read all the posts, so I apologise if it's been mentioned. But if breakdown, dead battery are a concern, why not a gas ram, and a Co2 bottle or oxy bottle, if you had 2, when one runs out just switch them over. Very cheap to get refilled, should have more than enough pressure etc, a simple latch and relief valve or similar set up? Just a thought.
you could just do it the simple way use a scissor jack chromed of course no need to have props should fit neatly between chassis rails use the type with a bolt head so you can access it with a socket on a cordless drill
any good Steve