High speed engine shut down

Is there any way to dissable the computers automatic overspeed engine shut down feature? I am going to use my 1994 EG33 I just bought in my homebuilt airplane. I dont' want the posibility of the engine shutting down on me if the propeller happens to overspeed. Is there any way I can obtain technical information or a diagram of the computer circuts? Does anyone or any Company sell SVX electrical maintenance manuals seprately? (the local dealer would only sell me the complete set at $80 bucks apiece) I am just starting to gather the information I need to fly with the 3.3L Subaru engine. I would appreciate and need all the wisdom and help I can get.

Thanks, Paul Minnicks, FAA rated Commercial pilot CFI, A&P mechanic with an IA

minnicksaviation@cs.com

[huck369]

I don't know it for a fact, but several on here have said the 92 SVX's ECU didn't have the limiters on them.

[svx_commuter]

My 92 will shift at the red line but I ma not aware of any "turn off the engine" feature if it goes above the red line. I am not going to even try that with the engine out of gear!

Originally posted by svx_commuter
My 92 will shift at the red line but I ma not aware of any "turn off the engine" feature if it goes above the red line. I am not going to even try that with the engine out of gear!

If I remember correctly, the EG33's ECU has a soft cut (drops fuel to 1/2 the cylinders) around 7k rpm (if you drive *really* hard continuously, the trans will shift so high that you can bounce off it periodically).

I've never bothered to find out how to disable it in the stock computer short of a "piggy-back" fuel/air modifier (a'al Greddy, APEXi, Blitz) but if you're going to do that you might as well spring for programmable engine management. Something simple ($700 under) would do since you're probably not dealing with the same auxilliary systems in an aircraft (unless you homebuilt guys use the P/S pump for something).

[Aredubjay]

Paul,
I have a scan of the ECU pinouts at home. I'll be happy to post them tonight if I can wrestle the computer away from the rest of my family, if you think they'll help.

Okay I am not a expert pilot here considering I'm still in school for aviation but how do you intend to hook up the dull exnition system including the magnetos? And do you really think that the SVX motor can stand up to such harsh conditions as those created during flight. Let me know know I am curious.

Okay for all you car guys an airplane dose not shift (it might have a constent speed prop but different ball game.) so he is talking about the power plant being put to full throtle for better performance, and not over speeding the prop during some manuvers. Also because of the diffrence in presure at different altitudes a pilot has to be able to change his own fuel to air mixture via a lever in the cockpit, as the aircraft gets higher, i think it is above 3000 feet MSL( Mean Sea Level) a pilot must start leaning out his/her mixture to keep the power plant running smooth. And in regards to the fuel pump he will have to have two seperate fuel delivery systems one mechanical and one eletrical. Unlike our cars there is two of everything on an airplane. However I am not a Mech just a pilot so let me know how it all goes and how you plan to do the exnition system.


Later
Chris

[Aredubjay]

Originally posted by sk8ing19
Okay I am not a expert pilot here considering I'm still in school for aviation but how do you intend to hook up the dull exnition system including the magnetos? And do you really think that the SVX motor can stand up to such harsh conditions as those created during flight. Let me know know I am curious.

Later
Chris

http://members.tripod.com/vjaqua/jpsub.html

http://aerocompinc.com/news/Spring00...pdate_2000.htm

http://aerocompinc.com/news/Summer99/boucher.htm

http://www.air-ryder.com/EnginesFrame1Source1.htm

Randy,

Like I said in my post i'm not a mech just a student pilot. I have never even heard of that being done. I still wonder how the magnetos and that whole system is setup. Great, thanks Randy one more thing on the internet to do other then my job.

Later
Chris

[Aredubjay]

Originally posted by sk8ing19
Great, thanks Randy one more thing on the internet to do other then my job.

Later
Chris

No problem. Always glad to take people's minds off the important things.


Randy (the enabler) i

Thanks to all,

1 Huck; I don't know the exact terminology of what, how or why the engine shuts down. I read that it does. Rght or Wrong?

2 Rev limiter, may be the term I looking for.

3 May be the soft cut feature is what they were talking about, but it said it stoped the engine.

4 Aredubjay; Yes, the ECU pinouts will help a lot.

5 Chris; One of the reasons I want to use the modern, superb SVX engine is to not have to use the old (FAA Certified), Failure prone, outdated, magneto powered, dual ignition. You were right about propeller overspeed, but it mainly happens on fixed pitch props not constant speed props. The weather conditions in the air on an engine are no worse than they are on the ground. I understand the ECU automaticly makes the necessary mixture changes for altitude/ temp up to around 14,000 ft MSL, freeing up the pilots work load. It's above 5,000 ft MSL that most aircrafts pilot operating handbook suggests that you start leaning the mixture with a recipacating airplane engine. I will have two fuel pumps, one electric and one hand pump (Wobble Pump). You know a lot more than me about the EG33 engine. So, I am also learning and need all the help I can get.

Thanks again, Paul

Paul,

See those sea level rules always mess me up due to the fact that all of my tranning takes place at 5200 feet MSL (Jeffco BJC). Thanks for the info on the ecu unit now that was one thing I never even heard of. If you ever get a chance, post some picts on your aircraft I would really like to see it. Well good luck.

Later
Chris

[svxter]

Good luck on your homebuilt, SVX-powered aircraft, Paul. Maybe you can be the first member of the SVX World Network Air Wing. But you'll have to install window separators in the cockpit side glass.

[Chris]

Well, while I lived in Seattle I met a guy with a SVX motor in a really fast plane. He did all sorts of mechanical mods to it. And to solve the problems of the factory ECU, he used a Haltech computer. I would suggest looking into this.

[Ron Mummert]

When you flyboys are finished with this project, can someone show me how to install a Pratt-Whitney R-1830 Wasp radial engine in my SVX? Also, is a nitrous kit available for this engine? Huck can help with my tranny options.
Thanks, Ron.

[Aredubjay]

Paul, here is page one of the ECU pinouts.