[marv1121]

I will be shopping for an RV-8 sometime soon I hope and need a little education on what are the changes and improvements to the RV-8 over the years. I fly a RV-4 now and got lucky and got one with all the improvements such as some thicker skins, longer gear legs, improved motor mount, better material for the cowling and the list goes on.
I am sure the RV-8 must have had some gradual improvements in the past several years just like the -4 did. Can anybody help me out here. I want to be an informed shopper.

 

[skylor]

RV-8 Changes

I will be shopping for an RV-8 sometime soon I hope and need a little education on what are the changes and improvements to the RV-8 over the years. I fly a RV-4 now and got lucky and got one with all the improvements such as some thicker skins, longer gear legs, improved motor mount, better material for the cowling and the list goes on.
I am sure the RV-8 must have had some gradual improvements in the past several years just like the -4 did. Can anybody help me out here. I want to be an informed shopper.

Here are the ones that I know of:

1. Aerobatic gross weight increased from 1550 to 1600 lbs. The early eights had a 1550 lb aerobatic gross weight. The wing at some point was updated to the "-1" configuration supposedly due to a minor design revision that was incorporated to increase parts commonality with the RV-7 wing when the RV-7 kits came out. (Don't quote me on this)

2. Fuselage redesigned to incorporate "fully pre-punched" parts. In the mid 2000's Van's completely redesigned the fuselage to the "-1" configuration to significantly increase the number of pre-punched parts and make jig-less construction possible. While all of the dimensions of the fuselage remained the same with older versions, the actual redesign was pretty significant in terms of overall parts count. Many more complex hydro formed parts are included in the -1 kit that both reduces the amount of builder fabrication required and reduces various assemblies down to single components thus reducing overall parts count. Many components of the -1 fuselage also incorporate integral lightening holes that weren't in the original design. I estimate that the -1 is possibly 10 to 15 lbs lighter than the original configuration.

3. Wing tip evolution. There have been at least 3 different wing tip designs used on the -8. The early kits included the "Horner" style tip. This tip has no provisions for internal light mounting and usually has a combination position/strobe light installed externally. Later kits ship with "sheared" wing tips. The sheared tips have a built in cutout and lense for internal position/ strobe lights. The earlier sheared tips have "small" light cutouts, and an aftward swept curved trailing edge. Later model sheared tips have have a straight trailing edge and larger light cutouts so that some types of landing and taxi lights can be incorporated. Opinions are all over the map regarding which tip design is "faster". Some folks here on the list swear the original Horner style is several knots faster, while a number of SARL guys I've spoken to seem believe the sheared design is faster.

There have also been minor changes in the resins used for the cowling and canopy skirt pieces. Early ones are yellowish/brown and later ones are pink, but I don't believe there is really any significant difference between these.

I don't believe there have been any significant changes with weldments and other components over the years.

Skylor
RV-8

 

[Robin8er]

They have also lightening holes that have been incorporated in various parts. Also I think they changed the design of the elevator.

 

[RV6_flyer]

RV-8 tail

The early tail kits use a lot of RV-6 parts. The newest tail kits have RV-7 parts. That means prepunched ribs and not just prepunched skins.

The most weight savings IMHO in the tail kit came with the incorporation of the RV-7 elevators. The relocation of the lead counterweight saves 1.25 pounds per elevator according to Van's "The List" parts weights. The latest kits also have lightening holes in the doubler that is added to the rear spar of the vertical stabilizer. The early plans lists the lightening holes as optional.