Series 5 with Series 7 Firewall Forward

[rcbif]

Does anybody here have a series 5 with a series 7 firewall forward, or know of anyone?

Was wondering if anything different has do be done during the installation/ build, or if the fuselage upfront is virtually identical? (ex: all hole provisions are there, and members are in same spot)

Also wondering about CG and W&B. I know the series 7 has the engine further out front than the 5, but now that I think about it, even the 7 does not require the forward sweep until you use an engine heavier than the 912.

[jmodguy]

I have a 5 and from what I understand is the fuselage dimensions are identical. For what it’s worth, Palmers bird is a 5 and he has a 7 FWF.

[GuppyWN]

I have a bud putting a 7 FF on a V right now. He already has the big elevator.

[mike92104]

What's the benefit to using the 7FF vs the 5?

[ken nougaret]

even the 7 does not require the forward sweep until you use an engine heavier than the 912.

You dont need the forward sweep for an O-200 either.

[PapuaPilot]

What's the benefit to using the 7FF vs the 5?

I remember asking the factory the same question. It is true that the basic dimensions of the model 5 and 7SS fuselages are the same. As far as differences the 7SS uses a boot cowl that can totally seal off the engine compartment. My model 5 has a rubber seal around the edge of the firewall that pushes against the cowling but doesn't totally seal.

My model 5 cowling had only top and bottom halves that went all the way back to the door frame. I opted to use them, but modified it so they separated just in front of the firewall too. Now I have 5 pieces (2 upper and 3 lower) that come off with Dzus fasteners. This mod was in lieu of purchasing the 7SS boot cowl and forward cowlings.

Here are before and after pictures of my cowlings being modified. I am happy with how it turned out, but it would be nice to have the cabin totally sealed off from the engine compartment in the event of an exhaust leak or fire.

FYI my wings are swept forward for the Continental IO-240 installation. It defiantly needed it.

23212

23213

[ken nougaret]

My model 7 in 2011 was also just the top and bottom cowl. I wanted a boot cowl, so I cut and glassed and made a 3 piece, with a separate boot cowl.

[rcbif]

What's the benefit to using the 7FF vs the 5?

Pretty sure the engine is moved forward, but having a hard time finding out how much. The cowl is defiantly longer.

See how tight it is here
https://www.youtube.com/watch?v=nrJaHwQT7Z4

compared to
https://www.youtube.com/watch?v=lIp70pgIV68

[Agfoxflyer]

I have a 5. My baggage is limited to 100lbs with a 912. They lengthened the engine mount to accommodate 150lbs with a 912. So guessing the cowling is longer.

[ken nougaret]

A piece of info; when I ordered my firewall forward with my 7SS, I got it for the Continental O-200. The instruction package that came with it is from a model 5.

[Esser]

It moves the engine forward 4". I would love to have my engine 4" further aft. My W and B is very forward. As is three of my friends. We all have our batteries in the rear. These are 912, 914, and 915. With Constant speed props, these are getting into O-200 weights. Funnily enough. My friend with the 912 has the forward sweep because he took a Subaru off of his plane and put the 912 on. It still has a too forward C of G.

[jrevens]

I have a 912 ULS & ground-adjustable Whirlwind prop - the CG is good, but would be even better with a little more weight in the nose. Completely empty with no fuel I'm still slightly aft of the forward limit. You could run out of fuel, jump out, and the airplane would probably land itself! :rolleyes:

[rcbif]

Interesting differences. Where is your battery at?

[jrevens]

My battery is on the firewall, and I don't need or want a lightweight Lithium battery.