PDA

View Full Version : Modifying Lycoming IO-540-AB1A5


RV10 UK Builder
01-14-2009, 12:54 PM
Hi everyone - yes Im new to this forum.

Anyway Im building the RV10 in the UK and looking at Lycoming engines.

So I was wondering if anyone out there knows what would need to be done to a AB1A5 engine to get it to the 260HP I would like as per the D4A5. Is it simply a case of adjusting the govener. If so what is the govener and where is it?

I would appreciate any help.

Mike S
01-14-2009, 12:58 PM
Hey Martin, welcome to VAF.

Good to have you on board.

bcondrey
01-14-2009, 01:44 PM
If it's really an IO-540-Axxx then it's an angle valve engine as opposed to the 260 HP version spec'd for the RV-10. MUCH different than the O-540-A series. The angle valve engines are physically larger and much heavier.

Bob
RV-10 N442PM (flying)

Allen Barrett
01-14-2009, 02:31 PM
but in this case the IO-540 AB1A5 is a parallel head engine using cast LW-13865 connecting rods versus forged LW-11750 in the D4A5. Also because of the lower rating, the engine uses the LW 13445 thin wall piston pin and the dynamic counterweights are different. Pretty much the rest is accessories.

Allen

RV10 UK Builder
01-15-2009, 02:24 AM
Thanks for the comments.

Alan, your points are very interesting.

So in your view would it be a case of simply changing the piston pins and crank rods as this is a used engine Im looking at that would need to be rebuilt anyway.

RV10 UK Builder
01-15-2009, 05:17 AM
Has anyone installed a IO 540 AB1A5 into an RV10 or used this engine as a base to start from?

I would like to hear from you.

Allen Barrett
01-15-2009, 06:53 AM
The AB1A5 could be converted at overhaul, sure. Do the appropriate upgrades and build it right it will make a good engine.

Allen

RV10 UK Builder
01-15-2009, 07:13 AM
Thanks for that - I would be interested to know from your experience if Vans are correct in what they say as below and is the IO 540 AB1A5 a rear inlet or updraft:

"The biggest hurdle would be the rear inlet fuel injector config. This won't
work on our engine mount/nose gear. It would have to be an updraft similar
to the -D4A5. The sump can be changed and the servo then mounted like
the D4A5. There may be other bits and pieces that would also be affected.

Thanks

Joe Blank
Builder Support
Vans Aircraft Inc."

Allen Barrett
01-15-2009, 07:19 AM
If someone were so inclined, and knowing the capabilities of the folks on VAF, there's not a doubt it could be done. Would I use the rear induction? NOt hardly. Not when I can turn it around, face it forward and gain some ponies :D

Allen

RV10 UK Builder
01-15-2009, 07:45 AM
Thank you again.

I dont suppose there would be any pictures somewhere that I could look at to get the difference between rear inlet and updraft clear in my head.

Mike S
01-15-2009, 08:55 AM
If someone were so inclined, and knowing the capabilities of the folks on VAF, there's not a doubt it could be done. Would I use the rear induction? NOt hardly. Not when I can turn it around, face it forward and gain some ponies :D

Allen

Is this just a matter of R/R the pan and a half turn???

Allen Barrett
01-15-2009, 09:12 AM
is a vertical induction engine not rear induction, so if you decided to use the engine as is, it would bolt on. You cant turn a sump around on the engine because of the way it is built, wont work. You have to change the sump and pipes to get the horizontal induction.

Allen