I just had CH IGNITIONS convert my FA 325R5D to pumped gas igntion system.
Planning to run it on a TOPFLITE P-47 85" c/w ROBART air retracts front and rear.
TopFlyte manual recommends 41 - 70 CC for gas engine. If I have worked out the conversion, my engine is 53cc., therefore in the mid range of the recommended engine size.
The engine weight prior to conversion was 5.4 lbs. Don't have it back yet to weigh but I am estimating the converted weight will be no more than 6.0 lbs.c/w the KELEO exhaust.
Your comments are welcome as is your advice and experience.

Going to finish in "Bubbletop", but have not selected the paint scheme yet. Any cool suggestions?
Thanx All
WW

Be advised that the Topflite recommendation "40 to 70 cc" most likely refers to 2-stroke engines.
Your Saito is 53 cc, but it is a fourstroke, AND it is a radial. Meaning that for its cylinder displacement, it is not going to be as strong as a 2-stroke, by quite a large margin.

I have a similar (WRT dimensions, weight and engine outfit) plane, a Seagull FW190A powered by an ASP radial converted to gasoline, and that ASP is 65 cc but it still is no powerhouse,
Your plane is about the same wingspan, by its factory specs a bit lighter than mine, but by and large pretty comparable. The Saito is, for its size, a pretty strong engine, probably fairly comparable to my ASP despite the difference in displacement, but that still means you're looking at 3 hp tops and a 20 x 8 prop at best.

It WILL fly, don't worry about that. But it will not be a power monster.

Thank you 1967brutus!
The original Top Flite instruction book's "Engine Selection" recommends "34.5cc to 45cc Glow Engine" OR "41cc to 70cc Gasoline Engine" on a "soft" mount system (which I plan to use).
I am not looking to roar around the skies attempting to emmulate any war ACE. I much prefer scale flying over crazy aerobatics. At 53cc I am right in the middle of the gas power range and therefore I will be a happy flyer. Besides that, less speed will give me more time to listen to the Keleo exhaust.....Adrian at CH Ignitions made a 45 second video of my engine running on the stand. I will have to be patient and avoid rushing the build.
When I figure out how to post pics I will send along some of the build.
Best regards
BLACCAT

Oh, don't worry, it WILL fly, but just that you keep in mind that a 52 cc 5 cyl fourstroke is NOT equivalent to a 52 cc single cylinder 2-stroke, not by a LONG shot.
And ANY glow engine converted to gasoline will lose about 20% of its rated power on glowfuel. Instantly.

I am sure it will fly, and indeed, it will fly rather scale like WRT speed. Mine does, at least.

WRT weight and wingspan fairly comparable, probably also reasonably comparable WRT engine power. about 82" WS and appr 24 lbs.
Mind you, what's in the vid is about as "hot" as it gets. No wide loops, no steep climbouts.

For the first bolded: Forget about the softmounts. A radial does not need them, those things run as smooth as silk with near perfect balance and near "electric-like" continuous torque,

Second bolded: click "manage attachments" and the site will allow you to upload pics if they are on your device, or if your storage is hooked up to your device.

Are you guys still out there? I am wondering which carb Adrian used on your conversation and if you are pumping fuel and which pump you are using?

I am still out here, but I cannot answer your question, since I still use the stock glow carb with the electronic solution.

I'm still here as well. Sorry for the delayed reply!! I didn't see your post.....
Adrian used an "APS PUMP" according to his invoice. See attached pics of the "POWERFUEL RX-U V2 SPIRITPUMPE" which he sent with my FA-325R5D, (not yet installed) but he did make a short video of it running in his shop.
The carb is a WALBRO. I think it is the factory original, but Adrian has added part between the carb and the intake on the engine. See pics.

Thanks BlacCat

Appreciate your response. Adrian sent the conversion parts but did not install or run my 325. I have had no good fortune with it this far. I am considering going back to the glow carb and methanol. I have messed with the walbro till frustrated. Worked with Adrian to no good solution. Hope yours is working to your satisfaction.

Hey Brutus, if your still out there, are you using the stock glow carb on your 325? And does exhaust pressure ( via a tap on the exhaust ring) provide enough pressure to run it without the APS pump?
Thanks guys
Aaron- (Hyjinx)

Still out here too.

I do not have the Saito 325, but the ASP FT400, and yes, using the stock glow carb, with as only modification WRT carb the main needle O-ring, plywood thermal isolators between engine block and the carb/header.
Since at low RPM the ASP, because of the layout of the intake arrangement suffered from oil separation in the intake tract, causing the vast majority of the oil only reaching one or two cylinders, I drilled a few cheater holes in the header elbow that at low RPM (high intake vacuum) blow back and atomize that oil towards the centre of the intake.

I am using indeed muffler pressure, and provided the tank is as short as possible behind the firewall, this allows a totally troublefree fuel supply, from idle to full throttle in all orientations.
It runs idle with the nose vertical, and will accept full throttle from that position without issues.

the fuel mixture arrangement is the one as discussed in the "electronic mixture control" thread, which also functions flawlessly.

Thank you Brutus. Appreciate your willingness to share your experience. Hope your having a great flying season!
Cheers.
Aaron (Hyjinx)

Hi there, what fuel pump do you use for the saito 5 cyclinder?
Thanks!

Maybe just scroll back a few posts? I think he mentioned it there...

Thanks John.
I have tried both the APS programmable, the APS original non programmable, and the MicroPump Great Britain pump. With the Walbro carb and a number of inlet spring changes in the walbros to no avail. I have become so frustrated with this conversion i am now waiting on parts to restore the intake and carb back to methanol. Hopefully once back on methanol the original exhaust ring tap will solve this issue, with the spark ignition.
Thanks for your input!
Aaron (Hyjinx)

I am 100% confident, that the "electronic solution" in my other thread, combined with just the methanol carb and muffler pressure, WILL give a usable solution, running gasoline.

The installation is basically plug&play, but the fuel mixture needs to be user-set in the TX programming, but it works excellent.
SIngle solution for a WIDE range of engines, 2 and 4 stroke, from below .30 cu.in (including the old OS Wankel) all the way up to and beyind 4.00 cu.in.