-10 Engine options

[Rx7thHeaven]

Hello,

I tried to do a search but didn't come up with anything so if this has already been discussed elsewhere, please just point me in that direction.

I am considering a -10 build after owning my -8 for about 3 years and beginning to think about a future need for more seats. When it comes to the engine, Vans recommends IO540 with up to 260hp. Just doing some quick searching on what is out there for sale, I am not having much luck finding 260hp variants but there is more than a few 300hp versions available. Is this an option that any others have gone with? Looking first at any safety issues with installing the higher HP engine and then any build related issues to fit the 300hp variant. I am not familiar enough to know if the mounts, accessories, intake/exhaust change much or what if any additional weight the 300hp has. Thanks in advance for any input!

Jonathan

[rocketman1988]

Those higher HP variants are likely the angle valve models, which can be as much as 60 pounds heavier than the parallel valve models. Not good in a -10. I have also heard that cowl fitting and possibly engine mount fitting can be an issue.

If you want the extra HP, look at cold air induction and higher compression. I am running a parallel valve IO-540 with CAI, 9:1, and EFII. It did nearly 300HP on the dyno.

Take a look at the W&B for a -10. Basically, everything that you put in the aircraft is aft CG. Adding lots of weight up front will likely require ballast with 1 or 2 front seat pilots...

[Rx7thHeaven]

Thank you for the info! I am less concerned with the extra power as I am am with availability of a 260hp engine. Granted I have not dug in too deep searching for one but they seem to be far less common than some of the other variants out there.

[Kyle Boatright]

Originally Posted by Rx7thHeaven

Thank you for the info! I am less concerned with the extra power as I am am with availability of a 260hp engine. Granted I have not dug in too deep searching for one but they seem to be far less common than some of the other variants out there.

Before the RV-10 came along, good -540 cores were cheap - there was little use for them in the experimental world. But the RV-10 market has consumed most of the good -540 parallel valve cores. I know because I looked for one for a couple of years and the best I could find were cores that had multiple overhauls and where the crank *might* have been good for one more overhaul. I didn't want to spend my money on a core like that. I also found a few "deals" where I might have come out way ahead or way underwater depending... I didn't want that level of risk.

That said, "deals" still come available from time to time (but you need to be able to make a decision and have money in hand). After that, Aerosport, Barrett, Van's, Lycoming, and Titan will all sell you a fine engine for ~$50K.

[Rx7thHeaven]

Thank you for the info. So it sounds like the extra HP itself is not a problem but should stick with a parallel valve engine.

[iwannarv]

New, used, overhauled, etc..... You'll be looking for a -D4A5 or -C4B5 variant. If you want HP, you can have Aerosport or Barrett build a nice engine of these variants to near 300hp. The airframe performs fantastic on stock 260HP, so I would not look to add weight to gain HP (angle valve). There are some experimental/aftermarket build shop versions that will use a heavy angle valve case and retrofit parallel valve cylinders that make a pretty bullet proof engine that is a little heavier, but not excessive. Best to call somebody like Barrett to inquire on that one...

[Fenderbean]

Originally Posted by rocketman1988

Those higher HP variants are likely the angle valve models, which can be as much as 60 pounds heavier than the parallel valve models. Not good in a -10. I have also heard that cowl fitting and possibly engine mount fitting can be an issue.

If you want the extra HP, look at cold air induction and higher compression. I am running a parallel valve IO-540 with CAI, 9:1, and EFII. It did nearly 300HP on the dyno.

Take a look at the W&B for a -10. Basically, everything that you put in the aircraft is aft CG. Adding lots of weight up front will likely require ballast with 1 or 2 front seat pilots...

I have read this before, what am I missing? if the aircraft is nose heavy already wouldnt the ballast need to be added on the back side of the CG to prevent further nose heavy condition? I dont see anyone installing much equipment further back to help lessen the nose heavy condition. Maybe im miss understanding

[rocketman1988]

Look at the sample W&B on vans site.

My -10 has an empty moment of 107.3. The recommended CG range is 107.84 - 116.24.

With a light pilot (150 lb) and minimum fuel of 5 gallons, the aircraft is basically at the forward CG limit. Adding 25 lbs of ballast in the baggage area helps significantly.

Now add another, say, 60 lbs to the engine weight due to an angle valve model. You will need to ADD more ballast just to get to the forward CG limit, if everything else remains constant...

Point is,If you add engine weight, you WILL need to balance it with ballast or remote avionics or something...

[Strasnuts]

I have an IO-540-N1A5. 260hp bigger crank and counterweights. A bit heavier but works great.

[BobTurner]

Originally Posted by Fenderbean

I dont see anyone installing much equipment further back to help lessen the nose heavy condition. Maybe im miss understanding

You may have seen comparisons of a 10 with a Cessna 182, with the -10 easily winning all comparisons except cg range. With a 182 you have to try hard to get it out of cg. The -10 isn’t like that, you need to be careful; without trying too hard, I can get my 10 out of forward limit (solo) or aft limit (gross weight, especially with reduced fuel). IMHO the best empty weight/balance is as discussed above-one where flying solo requires about 20 lbs of ballast in the baggage area. You don’t want that weight installed; for heavy, aft loads you just pour the water (or sand, or rocks) out. BTW, another -10 characteristic: If you take off with the cg near either limit, fore or aft, the cg will move even closer (or exceed) that limit as you burn gas. It’s important to calculate expected landing cg anytime you take off near either limit.