Showplanes -8 Cowl

Just curious on the Showplanes -8 Fastback and Cowl conversions...

On the cowling specifically, is there a different engine mount used- or perhaps a prop hub extension? Sorry for the dumb question, but since the cowling appears to be MUCH longer than the stock version, I was just wondering what the details were?

Man their conversions look sweet!

As far as I know you need a prop hub extender on the 4 cylinder. I did see one at Osh with a 6 cyl with no prop extension.
Really quality kits IMHO.

prop extension is needed

The cowling is about 2.5inches longer than standard therefore an extended hub is required on all 4cly.

Thanks....

Thanks, Patrick. That answers my question. Much appreciated.

I agree completely with what rv72004 said. The Showplanes.com cowl and fastback kit is of the highest quality. I've seen several completed RV8's with their products and they perform great and look even better. I know from personally observing the products closely. I am based at the same airport as Showplanes and as a matter of fact my company does their web site. Don't hesitate to contact them, they are more than happy to answer any and all questions.

Revival of an old thread.
With the Showplanes cowl and the necessary 2.5 inch prop extension for a 4 cyl engine can somebody enlighten me what (if any) G limits are imposed on the aircraft?

I was worried about that on mine (in the UK they dont like aeros with a prop extention) so i got MT to make me a prop that "fits" without any adaptors etc. they did this at no extra cost!!

see pics

Dave

I havent bought my cowl yet, but, if I'm not mistaken, you need to also use the ShowPlanes spinner (or another 15"(?) spinner) if you go with the ShowPlanes cowl....versus the stock Van's spinner. Just an FYI.

Joe

My spinner came with the prop

Dave

Dave, thank you for the information. Your MT prop, hydraulic or electric? I had seen the pictures of your airplane and noted it was a fastback didn't put two and two together that it was Showplanes. Beautiful airplane. I might be asking you more questions in the future.

It's hydraulic, I can dig the part no. Out from the paperwork next time I am at the workshop if you want.

Yes please, That would be great.

this is the info I had from MT

Dave



For the RV 8 with the 180HP Lyc. IO-360-() engine we will offer you our 3 bladed hydraulic constant speed propeller with a diameter of 183cm, and extended hub, propeller will operate with oil pressure to increase pitch ( no counterweights ).



Type: MTV-12-B/183-59b EUR 7.400,00

+ Spinner Assy P-285-4 EUR 980,00

--------------------

EUR 8.380,00

+ shipping crate EUR 160,00

--------------------

EUR 8.540,00



Prop will be painted in white with red tips, spinner assy is white.

Propeller will be shipped in assembled condition.

Delivery time will be approx. 8 weeks after order, we sell only according our general terms of sale.

Prices above are ex factory Atting/Germany without shipping or handling.

Prices above are without the German VAT, in case you do not have an European VAT Number we must charge additional the German VAT with 19% at present.

Terms of payment are full prepayment required with written order to start the production.

Offer is valid for the next 60 days, we sell only according our general terms of sale.



You could order either at our place direct (prices are above ) or at Van?s. In case you order at Van?s and do the shipping direct to the UK we must also charge the German VAT !

Any further question please let us know.

Appreciate your order.




Eric Greindl

MT-Propeller Entwicklung GmbH

Flugplatzstrasse 1

94348 Atting

Germany

ph. +49-9429-9409-19

prop ext limits and cowl

I have placed self imposed acro limits due to the prop extension. I dont know of any scientific data to support any limits it just makes sense to me that with any hub extension torque, gyro effects ect... will be greater on the crank with any "hard" acro. Likely non issue with low G maneauvers. I have spoken to many experts (engineers, prop mfg, engine builders) None drew any bad conclusions, I wont be entering any acro competition but that was never my mission to begin with.

As far as the cowling is concerned, The "footprint" for the spinner/cowling matchup is about 15 inches dia. The cowling was designed for a larger sized engine than 320/360 so I had some dimensional mods to make. I puchased a 14inch spinner from this site therefore had to "neck down" the opening for a good fit. I also had to shorten the cowl to fit for length dimension. I know that MT props come with a matched spinner but I dont know the diameter. Showplanes products are of the highest quality so no worries on that. I am very pleased with the company.

as a side note

hartzell sold (not sure if they still do) either a compact hub or extended hub propeller. Vans sells the compact (standard) hub Hartzell at a great discount. I chose to purchase the prop thru vans and use a Sabre Mfg hub extension. If you notice on the pic in prev posts the MT was built with an extended hub. Essentially two ways to achieve the same outcome.

Registration

Dave,

I'm a stickler for correct letter spacing and fonts. I wondered why you squished your E and I up against the tail, then I got it. Nice.

Don

Have there been any reports of reduced stability with the longer Showplanes cowl? Given that there's been an increase in "wetted area" ahead of the center of resistance, couldn't a builder encounter reduced stability? Has anyone considered using an RV-9 V Stab on a Showplanes cowl-ed RV8? Am I over thinking this? Would an RV-9 VS even fit on an RV-8?