BB vs. Czech Mate...

[Blue Foam]

A little bird recently sent me a link to an article about the Pratt test engineer who invented ADI. Among other fascinating things, he reliably got 3400+ HP from an R2800 and used this to diss the 4360 engineers. This is about the same or slightly higher power level than the Bear used this year. This begs a question:

Put this 3400 HP into BB and Czech Mate.

Who's on first?

[GeeBeeZ1931]

Re: BB vs. Czech Mate...

Hi Eric;

Please pardon my ignorance, but.......It was my understanding that The Bears engine was rated at 4000+ hp. Is that past history?

VERY interesting stats on the venerable R2800. Very interesting.

A few years back when Sherm blew the engine in the Yak(maybe his first year)I asked him if he was going to get a new 2800 HP motor as I think that was what Bob Yancy had been running, and he said he was going to do 2500 HP. I wonder if he's leery of too much power in the Yak because of its size?????? Maybe its speed because of the fabric covered tail.

As Sandy Sanders said: the Yak looks every inch the historic air racer. And I LOVE it and can't wait to see it back!

BIll Kohler

[Air Race Addict]

Re: BB vs. Czech Mate...

BB

BB????? OMG!!!!!
ME PLEEEZE! I'm having a brain freeze!!!!!
Yeah, it's me

[Apteryx]

Re: BB vs. Czech Mate...

BB????? OMG!!!!!
ME PLEEEZE! I'm having a brain freeze!!!!!
Yeah, it's me

Big Bossman ? (F7F's used R2800's)

[aflyer]

Re: BB vs. Czech Mate...

A little bird recently sent me a link to an article about the Pratt test engineer who invented ADI. Among other fascinating things, he reliably got 3400+ HP from an R2800 and used this to diss the 4360 engineers. This is about the same or slightly higher power level than the Bear used this year. This begs a question:

Put this 3400 HP into BB and Czech Mate.

Who's on first?

Eric, what is the link? I would like to read that article.

Thanks, John

[Peashooter]

Re: BB vs. Czech Mate...

I'd put two slow-nosecase 3350s in BB before hotting up R-2800s. It's all about reliability. Imagine BB with P-3 props and a race canopy. No wing clips necessary -- it came that way! Imagine the sound!

Hey Victor, I gotta Photoshop job for ya!

[matt]

Re: BB vs. Czech Mate...

i dunno peas, daryl greenameyers held up pretty good, i understand that it wasn't very modified but it was still pulling a lot of power quite often.

[Air Race Addict]

Re: BB vs. Czech Mate...

Big Bossman ? (F7F's used R2800's)

Thanks Man! Okay, now I'm back amongst the coherent. HAH! Not sure what happened, but that sure felt stupid.

[Peashooter]

Re: BB vs. Czech Mate...

i dunno peas, daryl greenameyers held up pretty good, i understand that it wasn't very modified but it was still pulling a lot of power quite often.

But Matt, you know that the Bear is a LOT faster that Conquest ever was. As much as I'll always love Conquest 1 and respect its place in air racing history, it's all about cubic inches! Peas

[Tin Man]

Re: BB vs. Czech Mate...

But Matt, you know that the Bear is a LOT faster that Conquest ever was. As much as I'll always love Conquest 1 and respect its place in air racing history, it's all about cubic inches! Peas

Don't forget aerodynamic and cooling drag.

[Low-n-Slow]

Re: BB vs. Czech Mate...

Eric, what is the link? I would like to read that article.

Thanks, John

hi John

I assume Eric is referring to Frank Walkers bio on the Aircraft Engine Historical Society site:

http://www.enginehistory.org/Frank%20WalkerWeb1.pdf

A truly great engineer.

cheers
Low

[MustangFan]

Re: BB vs. Czech Mate...

I'd put two slow-nosecase 3350s in BB before hotting up R-2800s. It's all about reliability. Imagine BB with P-3 props and a race canopy. No wing clips necessary -- it came that way! Imagine the sound!

Hey Victor, I gotta Photoshop job for ya!

Not to mention the wake turbulence! Imagine trying to PASS that beast...

[Blue Foam]

Re: BB vs. Czech Mate...

Imagine the sound!

Here's the link, quite the interesting engineer...

http://enginehistory.org/Frank%20WalkerWeb1.pdf

Yes, 3350's could be better; they are also heavier, bigger, and would require a lot of money and work. The idea of the 2800's mentioned in this article is that BB and CM already run them. So cost would be limited to finding out what Walker did and applying it along with whatever we could throw at it from today's perspective.

The Bear's 3350 is currently max'd somewhere just above 4000 HP, however the aircraft has flown many of its fastest laps on less. There is not a huge difference in the displacement: the 3350 is 20% larger than the 2800. Yes, there is no replacement for displacement, but remember that the Merlin is only 1650, half of a 3350 and 60% of a 2800. Merlins make quite the power density (best of any Unlimited), so apply that same density to the roundies and we would have 5800 and 6950 HP. Of course, neither engine would exist for more than a few revolutions at that power level since they were never made for it (neither was the Merlin, but for its size it's a better engine).

For reference, the 1945 production wartime-emergency-power on the 2800 was 3000 HP. This would give both BB and CM better power to weight than the Bear currently has. As the article states, Pratt typically tested its engines for long periods of time (longer than a race week) at WEP. As my friend pointed out, this was done on new production parts and with all the engineering of war-era Pratt and Whitney behind it. It's just something to think about.

[First time Juke]

Re: BB vs. Czech Mate...

Dudes,

No no intent to hijack a thread. Just to remind about the different sizes of RR Merlins. Here is a link:

http://freespace.virgin.net/john.dell/meandgr.htm

One thing I just realized was that Me 109 K-4 flew 441 mph tops with a Griffon sized engine. Merlins on Mustangs were only 27 litre displacements and still flew 440 mph ( and Griffon was 36+ litres and DB 605L right about 36 litres ).

DB 605L data; http://en.wikipedia.org/wiki/Daimler-Benz_DB_605

rgds,

Juke

[Peashooter]

Re: BB vs. Czech Mate...

Here's the link, quite the interesting engineer...

http://enginehistory.org/Frank%20WalkerWeb1.pdf

Yes, 3350's could be better; they are also heavier, bigger, and would require a lot of money and work. The idea of the 2800's mentioned in this article is that BB and CM already run them. So cost would be limited to finding out what Walker did and applying it along with whatever we could throw at it from today's perspective.

The Bear's 3350 is currently max'd somewhere just above 4000 HP, however the aircraft has flown many of its fastest laps on less. There is not a huge difference in the displacement: the 3350 is 20% larger than the 2800. Yes, there is no replacement for displacement, but remember that the Merlin is only 1650, half of a 3350 and 60% of a 2800. Merlins make quite the power density (best of any Unlimited), so apply that same density to the roundies and we would have 5800 and 6950 HP. Of course, neither engine would exist for more than a few revolutions at that power level since they were never made for it (neither was the Merlin, but for its size it's a better engine).

For reference, the 1945 production wartime-emergency-power on the 2800 was 3000 HP. This would give both BB and CM better power to weight than the Bear currently has. As the article states, Pratt typically tested its engines for long periods of time (longer than a race week) at WEP. As my friend pointed out, this was done on new production parts and with all the engineering of war-era Pratt and Whitney behind it. It's just something to think about.

Good points. I'm in for easy and cheap(er) -- just can't have it fast(soon).

Imagining 3350s on Bossman is like fantacizing about Mia Ham with double Ds. "Start me up!" (Sorry ladies, but you have your fantasies, too. And don't start with the Buick! )

A good friend who flew Thuderbolts out of Duxford said that with a full load of bombs, gas & ammo, they'd pull 80" from their R-2800s on takeoff.

Then post-war Republic gave him heavy, straight-wing F-84s. Those even had rpm guages on the main wheels to assure adequate rotation speed. Those jets were not for girls. 'Course, they kinda threw nukes like a girl...i.e., lobbed delivery.

All's fair in love and war...