The well tested O-235

[GlennBob]

 I'm seriously working at changing my EZ to accept an O-320 powerplant.  I've heard that it will shorten the runways, but mostly, . .improve top end speed.  I know there will be some increase in fuel burn,  but I think the trade off for the speed will be worth it.   There are a lot of modifications and exchanges necc. to make this happen, but I already have the engine and it's very low time. 

What is the scoop on this idea ?   The O-235 has 9.5:1  Pistons and dual lightspeed ignition and an Ellison TB.  Got the wheel pants and the ram air box.  Just wondering if I should go through the trouble if the little O-235 is really a good deal.   ? ? ?  Any feedback ?  Glennbob.

[LongEZDaveA]

I'm mostly happy with my O-235 Long.  I have the 9.7:1 CR Lycoming pistons that are for the -J or -F models.  With the high CR pistons, Hal Hunt 4 into 4 headers and ram air box, K&N air filter, and Lightspeed Plasma III EI, it does well.  I get around 2280 to 2300 RPM when I hit full throttle on take off and 2900 or a little less when racing full out with my Lightspeed prop.

I will admit that I often think about what it would be like to have more HP.  Even with the thoughts of more HP, I'm not even close to considering the down time it would take me to convert to an O-320. 

[GlennBob]

I don't have to consider the " Down time "  because I'm already there.  And frankly, . .I'm absolutely sick of it.  I bought this bird . .flying. . .(sort of) 5 years ago, . without paint and I needed to go through it.  Busy with work and other distractions, . .but now I'm getting close and I have both engines to choose from.  I know the O-320 will burn more fuel, but then I'm going faster so the total fuel for the trip really isn't much of a compromise.  They say it weighs more, .  . .yeah . .I think about 25 pounds.  That's 4 gallons of fuel ! !  Not enough of a diff for me.  So , . I have  to make some adjustments, but I don't think it's going to add much time to my final finish date.  So . .I'm leanin' towards the O-320.  Many things will transfer to the other engine, ,some will not.  But, . hey . .thanks for the come back ! !   Glennbob

[flyingwaldo]

I've never met anyone that regretted the O-320.  Can't say the same about the O-235.......

[srothert]

Couple other things to consider.
1) If you go back and look at the empty weights of 0-235 vs 0-320  Long-Ez, don't be surprised if you find about 100 lbs difference due to a larger prop, heavier prop extension, larger battery and the 20 lbs of weight that you carry in the nose to get the C/G in the right location.  I can barely lift my 0-320 Long-Ez with a full load of gas.  My next upgrade is an electric nose lift.

2) I don't have a fuel flow meter so can't comment on the burn rate.  I think comparable flow rates have been previously published in past issues of Central States Newsletters.

3) At the time that I bought an engine, 0-235 were in high demand because of other kits that were available in the marketplace and an 0-320 came along at about the same price.  I also considered the impact of living in the geographical location of high altitude airports and high density altitude in the summer.

Hope this helps in your decision making progress.

Steve Rothert
Albuquerque, NM

[GlennBob]

Thanks Steve  for the  other considerations regarding the O-320 engine.

I guess I'd be surprised if the additional equipment for the O-320 would add up to 100#'s.  Gary H. told me I could use the same prop extension, . .just re-machine the bolt holes for the wider pattern.  I have dual batteries in the nose now, so I don't think that would change.   I do agree that the center of gravity might move aft, but I was thinking of extending the nose a bit and move the batteries a touch forward to compensate.  See, . .there's a bunch more work to this thing.   So . .at the moment, .I'm leaning back to the O-235.   Gary H also told me that if I want to fly in this lifetime, . .(grin), ..I'd better stick with this engine, - a sentiment echoed by Terry S.   

Thanks again for your input ! !   I appreciate it ! 

Glennbob

[flyingwaldo]

I would never contradict Terry and Gary.  The sooner you finish (without making changes) the sooner you fly and enjoy the fruits of your efforts.  However..... the last time I took off behind an O-235 I had to throttle back to 1700 RPM to stay with him......  If you're OK with that, power on.
I didn't build my plane but have built many other large projects.  A small amount of time now to achieve years of increased satisfaction (as opposed to those that just have to redesign everything, argue the merits, and still haven't flown a tenth) should be considered.  Good luck whatever path you take!!

[Juan Rivera]

I am very happy with my upgrade to the Lyc 320.  I have a early narrow deck 320 with a conical mount and I had a 50 pound weight increase.   My old 0-235 had a #2 bolt pattern on the flange and the 320 has the same, so same prop extension unless you want to buy a longer one.  I would make the change again .

[GlennBob]

Hey  Great  info guys ! !    I'm just dying to get some air time in this thing, .  so . . I think we're gonna go with the O-235.  However, . .I should point out that I don't have a stock  O-235-L2C.  Mine has the high compress. pistons. 9.5 : 1,  and you can sure tell.  It cranks over quite hard.  So,  I have a few ponies added there,  plus now I have 4 single exhaust pipes rather than the 2 into 1 and I also have the Ellison T.B. and dual lightspeed ignition.  So . I think I'm creeping near the HP of the stock O-320.  (150hp).

We'll try this one now (235) and then later put in the 320 and find out we did all that conversion work for 10 extra knots ! !

GM