JasonM
Pattern Altitude
One turbo charged vs turbo normalized? What years where either made? Seems like all listings say SR22T.
Whats the difference in the SR22T and SR22TN?
- Thread starter JasonM
- Start date
Originally Cirrus used the Tornado Alley Turbo STC to build the SR22TN. They basically took their regular plane with the IO550K and bolted the TAT system to it right at the factory. The engine has the same compression and the turbo only maintains a charging pressure slightly above atmospheric (30.5in or so) to compensate for the effect of increased backpressure.
Two years ago or so, Cirrus listenend to the marketing people at Continental and decided to switch to the TSIO550 somethingortheother. It is rated at 10 or 15hp more than the NA engine with the turbonormalizer. In the tradition of Conti turbo engines, it has a lower compression than the NA engine and uses a boost pressure in the 36in range to provide the rated power.
The difference between the two is one of performance and religious beliefs. The T climbs a bit faster and burns more fuel. I would would love to have either of them
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TN is a bit more efficient and will carry power to a higher altitude.
NoHeat
Final Approach
Weilke has good info.
One big difference is just the year of manufacture of the plane.
Both kinds of turbocharging result in shorter longevity than normal aspiration, they say, but advocates say that the normalized version suffers less. It doesn't boost above sea level pressure. OTOH, by installing the Tornado Alley turbonormalizing kit on a new Continental engine, Cirrus voided Continental's warranty, so that during those years Cirrus had to provide its own warranty for the engine. After a few years of that, Cirrus switched to the Continental turbo, which is not normalized but came with a Continental warranty.
One big difference is just the year of manufacture of the plane.
Both kinds of turbocharging result in shorter longevity than normal aspiration, they say, but advocates say that the normalized version suffers less. It doesn't boost above sea level pressure. OTOH, by installing the Tornado Alley turbonormalizing kit on a new Continental engine, Cirrus voided Continental's warranty, so that during those years Cirrus had to provide its own warranty for the engine. After a few years of that, Cirrus switched to the Continental turbo, which is not normalized but came with a Continental warranty.
JasonM
Pattern Altitude
Thanks guys! So when exactly did it go from TN to T?
Dr. O
Pattern Altitude
I have long felt that turbocharging of most GA engines should not be full time. It should be selectable and used mainly for high altitude operation, say 8K to 10K and above, and/or high density altitude takeoffs. Engine life would be greatly improved. Turbo life would be improved. Lower altitude fuel flow would be less. And still give the benefits of high altitude speeds when the boost is on.
roncachamp
Final Approach
The N.
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Checkout_my_Six
Touchdown! Greaser!
So long as those CHTs are remaining low (below 380-400F ish)....those cylinders have not a clue what is attached to them....or pumping air to them. Keep em cool and they will last as long as any other cylinder. BTW there is a total cult following on how do keep those cylinders cool.....LOP vs ROP.
I have the factory turbo variety in my Bonanza, similar but different than the Cirrus engine.....the red headed step child of engines. It's less fuel efficient (about 1-1.5 gph more to drive the turbo), but it puts out at anything above 10,000 feet. Down low its nothing special....but up in the higher altitudes, specially above 10K feet, its a cruiser. The turbo makes my airplane a true 200 kt airplane....
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overdrive148
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overdrive148
PaulS
Touchdown! Greaser!
5...... the answer is 5.
roncachamp
Final Approach
Yup. "Solve for x" would have been better.
That's pretty much how I ran them in my Travelair with manual waste gates.
So long as those CHTs are remaining low (below 380-400F ish)....those cylinders have not a clue what is attached to them....or pumping air to them. Keep em cool and they will last as long as any other cylinder. BTW there is a total cult following on how do keep those cylinders cool.....LOP vs ROP.
I have the factory turbo variety in my Bonanza, similar but different than the Cirrus engine.....the red headed step child of engines. It's less fuel efficient (about 1-1.5 gph more to drive the turbo), but it puts out at anything above 10,000 feet. Down low its nothing special....but up in the higher altitudes, specially above 10K feet, its a cruiser. The turbo makes my airplane a true 200 kt airplane....
While the cylinders don't know from the extra pressure, the induction and exhaust system sure do. I'd want to bump compression ration and lower the waste gate settings for the turbo on your engine. Get some of that wasted fuel back.
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Checkout_my_Six
Touchdown! Greaser!
ya....more compression ratio would be good...but it ain't what we gots.
CMI has a thingy for this low compression configuration.
I suppose one day I could look into upgrading from the TSIO-520 to an TSIO-550....for a real barn burner. But, I suspect that will require $$$$ to purchase someone's STC.
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ya....more compression ratio would be good...but it ain't what we gots.
CMI has a thingy for this low compression configuration.
I suppose one day I could look into upgrading from the TSIO-520 to an TSIO-550....for a real barn burner. But, I suspect that will require $$$$ to purchase someone's STC.
One thing with the low CR, you could detune your waste gate for MoGas.
Checkout_my_Six
Touchdown! Greaser!
not really...It was de-rated using lower compressions (7.3:1) and still required 100LL to pass detonation testing.
This engine needs 32.5 inches of MP to make rated power.
Exactly, you won't be making rated power, turning down the boost will reduce that as well as increase the margin on detonation that I'm sure someone will shortly be along to explain doesn't exist.