griffin versus merlin

[Paynts]

having been newly bitten by the unlimited air racing bug I have a few questions I was hoping some of you knowledgeable guys could answer, do any racers use the larger Rolls royce griffin engine in their mustangs? and if not is there a reason -ie power to weight not so good? I know the griffin has a fair bit bigger displacement and during the WW2 it made alot more HP than a Merlin
second question, does anyone race a spitfire unlimited or standard?

thanks in advance for your replies

Simon

[David E. Wells]

Re: griffin versus merlin

Although a Merlin is 800cu in Less than a Griffon, the Merlin and Mustang have a Much smaller frontal area, but, more importantly, there were Very Few of the 2-speed, 2-stage supercharger units built for the Griffon, unlike the Merlin. On top of that, many, many of these parts, Merlin and Griffon have already been Destroyed through Racing efforts in Unlimited Hydroplanes and Aircraft, the units that do survive are Treasured and Valuable! You can read the American Allison into this equation also...D.

[mustang5151]

Re: griffin versus merlin

There have been some very successful Griffon-powered Mustangs at Reno over the years. Red Baron won 2 back to back Unlimited championships in 1977 and 1978. Miss Ashley was a beautiful hybrid Mustang that used a Griffon engine, and currently(and historically) Precious Metal(formerly World Jet) can be seen rounding the pylons at Reno. The potential is definitely there for the larger Griffon to out-perform the smaller cid Merlin, but it seems most Mustang teams prefer the Merlin to power their racer. I suppose parts are more readily available and there is more information and people to get the maximum out of the Merlin, but, as the Red Baron team showed us, the right combination of work, determination, money and luck.....you just never know!!!

[Paynts]

Re: griffin versus merlin

Mm interesting! after my intial post I spent a bit of time researching the griffin and discovered that the Budweiser unlimited hydrplane team of the 80s used a griffin wound up to 4000 +hp but that used turbo chargers and NOS as well as ADI
apparently the griffins limitation on power is running higher revs due to piston speeds. It seems that its displacement was larger mainly due to longer stroke. Although the engine wasn't just a stretched merlin it was purpose designed for carrier borne planes

Anyone know any more?

[Paynts]

Re: griffin versus merlin

I seem to be having a problem with posting on here so will try again

I hear what you say mustang 5151 and David about the lack of 2 speed 2 stage supercharger versions, what about the last Griffin engines as fitted to Shackelton maritime search planes?
I also did a bit of research and it seems that the griffin probably has problems pulling the much higher revs to get more HP
Although in the 1980s a griffin engine budweiser hydroplane boat was giving 4000 + hp all be it with NOS and turbos rather than a supercharger
regards Simon

[r_willy]

Re: griffin versus merlin

"Griffon-Powered Mustangs" by Grantham and Veronico is a great book on the subject - http://tinyurl.com/2xa7yd - Google or Amazon should be able to find you a copy.

[Paynts]

Re: griffin versus merlin

thanks for that R willy!
I actually found it on Amazon- think I might invest!

[number17fan]

Re: griffin versus merlin

Way back in the day there was a Griffon Spit (mk19?) from Canada

[W J Pearce]

Re: griffin versus merlin

Since Speed is just lurking, I'll post some info in the hopes that he will chime in with the real truth, rather than my memory of it.

The hydroplane stuff was mostly non-airworthy stuff. Hydroplaners would trade good stuff for non-airworthy stuff. Yes a lot of parts were used up but probably less than we think.

The Merlin got more air racing development that did the Griffon. Several air racers including Strega were thinking of switching to the Griffon, but that never happened. Most of, if not all the the Griffons that are out there today are from a Shackleton patrol bomber.

The props from the Shackleton are the dual rotation units that Red Baron, Miss Ashley II, and Precious Metal use. They are set for cruising more than speed. There are NO spare 5 blade Rotol props for the Griffon. The few that exist are on Griffon Spits.

With a Griffon you get a heavier, slightly larger engine, with more displacement and perhapses more potential, that has not benefited form the post WWII racing development that the Merlin has. Add to that a less than ideal propeller setup and the added weight and complexity of the dual unit, and you get why the Merlin is still the inline king.

All info above has been obtained vicariously.

[spacegrrrl]

Re: griffin versus merlin

Its my understanding there are a couple of issues that have held the Griffon back. The supercharger is one of them. In general it can't generate the boost levels to match the Merlin. The Red Baron was engine failure was due to the failure of custom blower gears that were made to try and address that problem (at least I think that's what I remember). I've been told Griffons are easier to come by as there aren't any planes that use them anymore and the British were using them till relatively recently. (Well, there are a couple of privately owned flying Fireflys that use Griffons) The last military use was the Avro Shackleton bomber. I believe that Bill Rogers got his engine and prop from England as surplused Shackleton spares.

The Griffon is heavier as well. I've no doubt that if someone put the years of serious development into a Griffon that has gone into the Merlins used in the races today that something could be competitive.

By the way, there is an intact (well, it was when they left it) Shackleton out in the middle of the Sahara desert. It was forced down out there by a sand storm. There are 4 Griffons right there! ;-)

Michele

[W J Pearce]

Re: griffin versus merlin

Now there was the 2 stage, 3 speed Griffon 101 that propelled the Spiteful XVI to 494. But there were only a few 101s made. They did make good superchargers for the Griffon, just not on the Shackleton.

I think the Griff would be better than the Merlin if the parts/time/money was there. I still dream of a Doc built RAT 101 in Stiletto!

[spacegrrrl]

Re: griffin versus merlin

Actually on other thing I forgot. The 5 bladed prop used on the Spitfire would likely be better than the counter rotating ones everyone has used so far. However I understand they are insanely rare.

Michele

[ebutner]

Re: griffin versus merlin

Didn't Clay Lacy run a 5 blade?... Long time ago, but I think I remember it that way. Purple 64 Mutang..He kept it at Van Nyes.

[RichH]

Re: griffin versus merlin

Its my understanding there are a couple of issues that have held the Griffon back. The supercharger is one of them. In general it can't generate the boost levels to match the Merlin. Michele

Along those lines, and something I haven't seen discussed, is that Packard did not license build the Griffon. From what I understand, Packard made significant changes to the blower section, as opposed to the British built engines.

[Paynts]

Re: griffin versus merlin

so what kind of power is a race merlin producing? somewhere near 4000, or more? or is no one going to tell?