Irvine 72 tach readings
 

Irvine 72 on a fourchamber flatdisk quiet pipe and a perry regulator VP30.
Fuel 10% nitro 20% oil halfsyntetic
Propeller APC 16x6@8500rpm

This engine is almost new and has only a gallon of fuel through it. Throttle response is fast and the sound is deep, great;)

RE: Irvine 72 tach readings
 

I have an Irvine 72 with nothing fancy. If you would like I will get prop and thrust data but it may not be what you are looking for.

Bill

RE: Irvine 72 tach readings
 

Please write here the prop and thrust data for your Irvine72. I am interested too see how other people are using these beatiful engines.

Mine is one of the last ones made in the UK. The newer ones are made by OS in Japan, but I dont know if there will be any difference. I hope they dont change the carburetor so much because I really liked them and they work great in combination with a Perry pump VP30.

RE: Irvine 72 tach readings
 

Sorry it has taken a few days to get the data.

Irvine 72
Looks like it has a stock muffler with exhaust extension.
Prop: 13 x 8 MA classic
RPM: 9200/9300 RPM
Thrust: 8# 9oz
Fuel: 20% nitro

The engine is on a 4* 60, which does not have a cowl. No attempt was made to retune for maximum RPM since the airframe drag is big and airspeed changes little from half to full throttle. The thrust varied between 8# 6oz to 8# 13oz and settled in at 8# 9oz.

Notes from a year ago indicate:
Prop: 14 x 8 MA
RPM: 8100/8200 RPM
Notes indicate the prop was changed because the engine sounds better with a 13 x 8. Both props had lots of Hi needle range.

Hope the information helps.

Bill

RE: Irvine 72 tach readings
 

Going back to your comment about using a Perry pump, I have purchased one to use with my Irvine 72 and it states that I should either take vacuum from the centre of the cr4ankshaft cover or through thes ide of the engine case. Can I ask how you have done this?
:eek::eek:

RE: Irvine 72 tach readings
 

Bill, this is an Irvine Q-72 from the mid 80s and it turns an APC 14x6 at 10,000 rpm like most .91s do I run it on Fox 5% fuel with 20% castor. The one with the red head is a Q-40, the Q-40 has the same stroke as a .46 but a .030" smaller bore than the standard 40.

RE: Irvine 72 tach readings
 

Hi, I have an awesome Irvine 72, and I am using a Perry Pump on another plane. The pump is attached to the engine crank case of a Saito .91 through the backplate. It works great! It adds instant throttle response, and very consistent fuel regulation with the carb. I haven't had any unusual fuel delivery problems with the Irvine engine. However, adding a Perry pump system to this engine might get you a spectacular performing engine with great throttle response. I haven't add the pump to the Irvine because I feel that the increase of performance would me minimal since the engine is one of the best engines I have ever had or witnessed.


In case it helps anyone, here are some performance readings for the Irvine 72 ABC. Compare these to your 75 size engine!
Fuel: 15% Cool Power MV (18% syn oil)
Glow plug: OS #8
Temp: 55F
Humidity 39%
29.92"

Master Airscrew S-2 15x6@9,500
Zinger wood 14x10@6500
APC 14x6@10,000
Master Airscrew K ser. 13x8@9,900
APC 13x8@10,500
Master Airscrew S-2 13x6@10,000
Master Airscrew K ser. 13x6@11,600
Zinger wood 13x5@11,100
Master Airscrew K ser. 12x8@11,100
Master Airscrew K ser. 12x6@12,900