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Discussion Starter · #1 ·
Rotomaster turbos, PFM or PMF? On the manifolds.

Whats it capable of performance wise? Thinking small big block, 396/427...

just looked too too cool to pass up!
 

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Discussion Starter · #3 ·
What size turbos?
This is the part number off them. When I google it, all that comes up is cummins diesel stuff. Rotomaster part#600586-05. They don't seem very big for a big block, I assume this kit was a bolt on for a stock motor? It was from a jet boat so probably only designed to run 5000 rpm. I just liked the vintage cool factor, but would like to know what I can get out of it. As we know, v-drive's love RPM!
 

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Discussion Starter · #5 ·
Ya might get ahold of steveo143 on the board he,s pretty sharp on the turbo stuff!
Thanks. I'd be interested in any literature on it or what it's original application was, or most interesting, if anyone's run this setup... It seems like a Banks kit but doesn't say banks anywhere on it. My guess is that it's early 70's?

Is Steveo the guy with that 1800hp v drive tunnel?
 

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PFM stands for Performance First Marine. They made a Turbo kit in the 70's. The intercooler was severely lacking and the boost limiting device in the tubes going to the manifold weren't great either.
Here is some info on them: PFM Eliminator Turbo

We Ran a PFM set up on my son's Campbell with a Bank's intercooler. It had two Holly $ barrel carbs and the manifold was not inter connected. The carbs were boost referenced, but it was very hard to tune, wanted to run like two separate 4 cylinder engines and was always way too rich at low speed, but ok at high speed.

When my son sold the boat the new owner took it to AZ Speed and Marine and they put on EFI with a closed loop O2 sensors and it really came to life, no longer too rich and makes a ton of HP.

Here is what someone else said from the link above: PFM made a bunch of different turbo set ups...I am running a modified version on my 468, my uncle is running one on his 580 chevy. I run 6 lbs of boost, he runs 22lbs. You can set that thing up how ever you want...is it a single carb set up or dual carb? Intercooled or not? Wastegates?Pictures would be very helpful. The general rule of thumb is unless it is built for it run 8 lbs or less. My unle runs an MSD ignition on his and has no problem....I opted for a bit of insurance and got a Mallory BTC...it takes timing out as boost rises.

You should be able to make it run, but I would look into getting a better intercooler.
Dave
 

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Thanks. I'd be interested in any literature on it or what it's original application was, or most interesting, if anyone's run this setup... It seems like a Banks kit but doesn't say banks anywhere on it. My guess is that it's early 70's?

Is Steveo the guy with that 1800hp v drive tunnel?
You can see the PFM markings on your kit, Banks had his name all over his pieces. I believe the Rotomaster turbos were replacements, I seem to recall that PFM originally used the same Rajay turbos that Banks and Race Aero did, but not positive about that fact.

Steveo143 has a couple of turbo engines that I built for him. Actually I rebuilt the 496 that's in his green Schiada, and I also built a 621 cubic inch all aluminum engine for him that has yet to run. He waited a really long time for some special parts to be made for his turbo kit.

Back in the late 70's when I worked for Gale Banks, there was some disagreement as to who copied who. The PFM setup was very similar to the Banks turbo kits. Banks used a little box on the intake like the PFM piece in your photo only on his low horsepower engines, maybe 5 psi boost and 550 hp. They simply run cool water through the housing of the aluminum box, and don't do much about cooling the mixture.

PFM also had some intercoolers that used the same radiators as the Banks kit. The PFM intercooler was finned similar to some of their other components.
 

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Looks like single 4150. So I would say 650h.p. max
The carburetor is actually not the determining factor on horsepower output from the old turbo kits. Banks had one that was sold as 850 HP with a single 850 Holley carb.

There is a direct correlation between boost and horsepower. The simple way of looking at it is that more boost makes more power, with other factors influencing the power output. You could make more boost with those turbos than the engine would like with that little box. One difference with the PFM setup to the others is there is some sort of valve in between the turbo and "the box",, unless it has been removed as many do with that setup. Banks and Race Aero used a bypass hole drilled in the turbo exhaust housing to limit boost, but of course that also killed bottom end power.
 

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Thanks Barry for jumping in on here. IMHO PFM was copying Banks all of the time. The subject system of this thread is like what Banks made for Mercruiser, 5/7 lbs. boost. The Rotomaster turbos are the same as Ray Jay 301's. If I were to run the OP system I would use the large intercooler and add wastegates.
 

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Discussion Starter · #11 ·
Wow thanks guys! I've not had any luck finding ANYONE who even has a clue what this kit is! I bought the kit after seeing a pic a friend sent me. I probably spent about as much time with it in my physical presence as it took to wind the 4 bolts in that are holding it to an beat 396 in that pic. I had to head to work for the next couple months... So bear with me as I can't take any more detailed pics atm...
Briefly, some of the points mentioned, there is some sort of Venturi in those tubes (someone said "boost limiting valves") they are still there, the intake "hat" has no aftercooler as such, just a water jacket. The one thing I found odd was that the carburetor base (it's 4150) is jacketed as well but it seems that it was plumbed for engine oil to pass through there, to the turbos, then drain to the sump???? WTF? Someone also mentioned Ray-jay, best I could find on line, Rotomaster bought out ray-jay or vise versa,.. there are no waste gates, however I have not inspected close enough to verify a drilled bypass in the housing.

What I would like to do, is build something to work with this setup, it doesn't have to be crazy, this will be the third combination in this boat. There's a carburated 489, a hilborn injected 598 and now this turbo setup... I'm thinking this engine should be a driver... A hot driver, but a driver that doesn't eat valve springs for breakfast! That's why I was thinking 396/427. Leaning towards 427 for the bore size, maybe solid flat tappet cam and pump gas compression. I am hoping to spin 7000 RPM. I have no idea if I'm out to lunch on my expectations/desires! I have LOTS of in depth Holley tuning experience, boost referencing is no problem I just wonder how temperamental a combo such as this will be?

thanks guys
 
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