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zammer · 09-19-2010, 10:12 AM

I decided to not cut the cylinder and just modify the top rack ram pivot out further so the stroke would be longer & at the same time it would give more leverage to get the top out of its retracted position from behind the rear seat.
To give you an idea of the force needed, these cylinders are pushing about 700 lbs EACH around 100 psi supply pressure. I changed the cylinders out once to larger ones as the first set i tried didn't have quite enough force . The first cylinder i put in was a 63 x 150 mm ( 2.5" diameter, which was good for 490 lbs @ 100 psi ) and the second one which worked good was a 82x150 mm (3.2" diameter)

I also put in a tension spring on the opposite side of each cylinder to assist them to open, and to resist the frame when its going down towards the windshield.. The spring is set up so it will be completely hidden and it just adds a nicer flow to when the top is going up and down..

09-19-2010, 10:12 AM	#57
zammer Addicted user Join Date: Sep 2009 Location: Edmonton, Alberta Posts: 369	Re: Blazer retractable convertible top I decided to not cut the cylinder and just modify the top rack ram pivot out further so the stroke would be longer & at the same time it would give more leverage to get the top out of its retracted position from behind the rear seat. To give you an idea of the force needed, these cylinders are pushing about 700 lbs EACH around 100 psi supply pressure. I changed the cylinders out once to larger ones as the first set i tried didn't have quite enough force . The first cylinder i put in was a 63 x 150 mm ( 2.5" diameter, which was good for 490 lbs @ 100 psi ) and the second one which worked good was a 82x150 mm (3.2" diameter) I also put in a tension spring on the opposite side of each cylinder to assist them to open, and to resist the frame when its going down towards the windshield.. The spring is set up so it will be completely hidden and it just adds a nicer flow to when the top is going up and down..