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Does anyone know if it would be possible/how much machining it would take to put the longer stroke 356, 9 main bearing crank into the 327/359 9 main bearing engine block?

I have looked around on some of the specifications documents on this site but can't find anything that gives much evidence to this.

Thanks,

John R.

John, the crankshafts are VERY different and though I have no personal knowledge I doubt they'd interchange even with extensive work. The 356 crank has considerably greater main bearing area (length of journals), the counterweights are bolted to it and overlap the journals. The 359 crank has shorter main bearing length and intergral counterweighting. The length of each of the main bearing journals for each crank is given in the engine specifications, and this may be of some help to you.

Thanks. I haven't been able to find the cylinder bore spacing for the 356 & 327/359. If those aren't the same it definitely wouldn't interchange.

John

You can answer your own question about bore spacing by checking cylinder head or cylinder head gasket interchange. Parts book for the appropriate years is on this site, though a Hollander's may be quicker.

Hollanders will also give you the answer about the crankshaft interchange between a 356 and any of the other postwar 8s - NO. Whether NO can be made a YES by some machining, I don't know.

Founds the 356 heads can be interchanged to 288/327/359. So I guess it still is a maybe.

John

The 359 crank will drop right into a 51-53 9 main block. Can about guarantee the 356 will not. You would also have cam and block clearance issues even with the extra 1/8 stroke of the 356 and be stuck using its incredibly long con rods because of its huge rod journals. I think that would put the wrist pins just about at deck height.

For the ultimate in a 51-54 car, you could just use a 356 and fit it with aluminum head and manifold to bring its weight down to approx that of the original engine. There is no great difference in length, only height.

Just for reference, the revised six of 38(?) set the bore (thru 53) and bore spacing for all the later "new" engines including the 356,288,327,and359.

Dear John:

Lengthening stroke to increase horsepower is highly asymptotic. In the 359 they were claiming almost as much torque as the V-12 and 37 more horsepower. However, the long stroke limits how fast the motor can spin.

Perhaps a better route might be to start with the 288 and hang a supercharger on it. Given it is less undersquare it might be able to spin fast enough to handle the blower.
The ignition system would also have to be highly modified to produce over 35kv in firing line required by the blower.

I'm not much of a hot rodder and am not a student on cams, but I do know that the more stuff you can cram into a cylinder the more power.

This might be a faster way to turn cash into smoke.

I like the 327 motor and think it is under appreciated due to Ultramatic. Without OEM pistons, new carburation, etal, I don't think it is possible to rebuild them to original horsepower.

"I like the 327 motor and think it is under appreciated due to Ultramatic."

I don't quite understand that statement.


"Without OEM pistons, new carburation, etal, I don't think it is possible to rebuild them to original horsepower."


I know several carb rebuilders that can do a carb BETTER than new. Same for machine work, or ignition, or what have you. I would think quality pistons would be a fine replacement for OEM, as are most parts in general. I think, as Ross has pointed out, it's about doing the WHOLE deal, valve job, pistons, rings, and all. I think with a proper rebuild, original horsepower is more than attainable.


Also, let's not forget, these were still mass produced cars, without the attention per unit that we dote on them.

You could make it run BETTER than new if you also cared about cleaning manifolds, deburring edges on port entrances, gasket matching, light cleaning porting, polishing, etc.

But really, when you gain 15hp out of all that, was it worth the time and money, for a car that isn't a race car, and you have no one to race?


As someone here once said, "I've never been in a Packard street race!"

I think of it every time i want to hot rod my Packard; if i want a fast car, there's way better and cheaper ways to go than a Packard.



HOWEVER. if i was going to hotrod a packard, maybe i'd put a supercharger on a Packard V8 after boring it out, then my second vote would be split between blowing a 288 (for the reasons you state) and blowing a 327 (because you can get one with 9 mains.)

Tim: "This might be a faster way to turn cash into smoke."
This is always the case. :) But it is a lot of fun.

It sounds like I am trying to Hot Rod an engine, actually I want to improve the efficiency/fuel economy of a Packard. My first thoughts were a longer stroke engine would produce more torque allowing the car to accelerate more easily and not need to be revved as much, which uses proportionately more fuel and a long stroke engine can't do anyway.

I am thinking I would use a 356 engine at this point.

I was going to use computerized engine management: port fuel injection and distributor-less ignition to get more power from the same amount of fuel.

All flat heads have poor breathing characteristics. My thought is to add low boost (5 psi or less) to counteract this and increase torque as well. I would use 2 twin scroll turbos, the smallest possible that won't choke at redline even if not much extra hp is created there. Looking for the earliest onset of boost and an increase in torque. Intercooling would increase efficiency, too.

Use a ZF 8 speed automatic transmission to further improve fuel economy.

But I want to keep the car looking stock.

Fascinating stuff. Never had any problem with the aftermarket pistons in the twenty plus sets I've installed, but even when screaming at the top of their lungs piston speed doesn't even approach 3000 fpm in these engines. There is plenty of friction from all that bearing area but the plus side is that it keeps the components from migrating to other parts of the engine compartment.

I am something of a skeptic about the nine-main 51-54 engines; I think it was a sales point more than a genuine quality enhancement. I can not tell the difference between say a 51 300 and a 51 Patrician in driving no matter how carefully I listen. And I would point out far as warming up a 51-54 nine main is concerned that the crank is probably not as torsionaly stiff as a five main as evidenced by the fact that Packard fitted them with much larger vibration dampers than the five mainers got.

Cortcomp is correct to note that these were production engines and subject to casting variations. Did a valve job on a 51 recently where 6 of the 8 intake ports lined up with the valve seats quite well, and two were at least 3/32 off making a big speed bump. This is quite typical and why every engine I do here gets at least a rudimentary porting job. Seems to make a nice difference.


The biggest problem with Packard gas mileage is that the cars are so un-aerodynamic and often at cruising speed the engines are turning faster than they need to because of lack of extra ratios.