stunthanger.com
Engine basics => Engine set up tips => Topic started by: Andrew Tinsley on March 01, 2016, 01:40:16 PM
-
I recently got an ASP 25 in a bunch of engines that I bought. I was about to toss it into my junk box, when I thought "maybe worth a second look". I cleaned it up and replaced a missing head bolt. H'm not bad, plenty of compression and no obvious rod or bearing problems. I made up a venturi for it, using LA 25 S inner dimensions and used an OS NVA. This ASP 25 had a pinch bolt retaining system, so not a drop in venturi replacement.
I then put it into a Flite Streak, after removing an LA 25. I used an APC 9x4 and the tank etc was straight BBTU set up, except I used the ASP silencer. It ran like a good un, if anything a bit more power than the LA25, but who is bothered about minor things like this?
OK ASP may not have the OS reputation and the ASP 25 is a tad heavier although it looks like a ball raced engine (although it has not been stripped down to check this) and it is a real ABC, not the OS nickel coating. Thinking about it, the LA 25 is no great shakes in the quality of materials stakes.
ASPs (Magnums etc are the same thing) are cheap to buy and seem every bit as good as an LA 25.
If anyone else has one, might be worth a try, if they can make the venturi. The ASP 25 is still in production, so if it is as good as I think (confirmation would be good!), then we have an LA25 replacement, which is still made.
Andrew.
-
I have two older OS .25 FX and one new ASP/Magnum .25... side by side they are near identical and all three run the same to my Tach and ear
Long term reliability....duno...but I paid exactly half for the ASP version from Hobby King USA ware house
-
What little I've run it I sure like my Magnum 35. I suspect an ASP/Magnum/Whatever 25 would work pretty well.
-
One orf these had a lean run on its first flight on a 9 x 4 in a goldberg shoestring when temp. was in the 30s & and lost some comp.
(http://thumbs4.ebaystatic.com/d/l225/m/mT_6yvRjfvvrtlhDV2QzHIQ.jpg)
was still going strong :-\ more than 10 gallons of comercial junk fuel later .
a 10 x 6 tornado worn to 9 1/2 in ( polypropolene ) in a noblerish 45 ish ounce everyday hack .
was planted ' once or twice ' too . Fox 25 intake filed to fit case & Taipan spray bar that leaked
giving t a nice burbly run - like the Emulsification tubes in a WEBER . ;D LL~
-
First off, i love magnum and asp engines. But what about the k&b 28 from county line hobbies? It says it's 7.2 oz. The Fox 35 was 7 or 7.1 oz. What little experience i have with these k&b sportsters is that they are extremely powerful.
http://www.countylinehobbies.com/kb28colien.html
-
I think you guys are finding the same thing I found. Most if not all of these sort of smaller RC sport engines will work great for stunt with no/minimal modifications as long as you don't try to run them like a Fox 35. The stunt world is ripe for a repetition of my previous small engine experiments, Search for small engine experiments brett for my suggested approach.
The key is to use a commonly-available 4" pitch prop, of course, so you end up running 12000 in the air instead of 8500.
Brett