M

morervfun

I'm New Here
I am thinking about selling my I 0 360 200hp out of my RV-8 and buying the new I0 360 250hp
I am not an engineer and did not build my RV , My question is will the extra hp give me the performance of a rocket or are my wings to big to allow any noticable speed increase.
 
How much over VNE are you looking for?

Just my opinion, it would be a huge waist of money.
 
Welcome !!!!

Hello Doug, welcome to VAF.

Good to have you aboard.

I suspect that the extra HP wont give you that much in speed, but the climb should certainly wake up.
 
Welcome Doug....

....to VAF. I know one guy in Atlanta, Mike Stewart who has a 540 Lyc in his -8 and the vertical performance is phenomenal and his cruise is around 225MPH, close to but not over VNE.

Seems to me that the 250 Lyc would be an easier mod because the 6 cyl needs a new engine mount.

Does the 250 HP engine fit the same mount that you now have?

Regards,
 
RV8 RE engine

I talked to someone from Dallas that had a friend that put the 4cyl 250hp engine in his plane and he said it out performed the F-1 rocket,
The expense would be about 11k. If it gave me 25 mph more it would be worth it. I have the 3 blade MT prop and was told I would have to go to the 2 blade prop to get the speed. The big question is the wing the RV-4s wing is smaller and looks more aerodynamic.
And yes the 250 fits same mounts nothing different but the power and cost.
 
Lycon, for one as I recall.

Dave Anders has one in his record holding RV 4, I do believe.

Barrett Performance can probably do one for you, Ditto AeroSport.. Dont know if Mattituck will, but you can check.

I am sure there are others, but the ones above are well known, and respected.

It is not that big a thing to make HP, but it will effect reliability/longevity. And, liability issues:mad::eek:

Probably why you dont see such things advertised much.
 
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The question of more power comes up fairly often and in every discussion I read, it comes out that more HP really adds to your climb but not so much to your cruise speed. Something about needing to square the power to double the speed or some such higher math.

You might be better off taking that $11K and making improvements to clean up your -8 aerodynamically. It might take a little bit of time but it would be a good challenge.

Things to look at are:
New Sam James cowl w/ plennum
Two bladed prop
Fairing alighnment
Rigging
Tailwheel fairing

Check with the racers for more details.

Bob A, jump in here.
 
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