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I know that at some point, a few 3.0 liter Montreal V8s were built. Out of curiosity, what is the maximum displacement possible for this block? This assumes both a custom crankshaft (and probably connecting rods) and new pistons and liners.

In other words, what is the maximum stroke and the maximum bore allowable? (As an aside, I'd be curious to find out what the maximum PRACTICAL bore & stroke might be.)

Thanks in advance!

-Joe in SoFla
 

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I know that at some point, a few 3.0 liter Montreal V8s were built. Out of curiosity, what is the maximum displacement possible for this block? This assumes both a custom crankshaft (and probably connecting rods) and new pistons and liners.

In other words, what is the maximum stroke and the maximum bore allowable? (As an aside, I'd be curious to find out what the maximum PRACTICAL bore & stroke might be.)

Thanks in advance!

-Joe in SoFla

I'm not sure of the maximum bore and stroke, but I do know some flat plane crankshafts were made and cars raced with them..
 

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The marine version of the Montreal V8 was taken up to 2997 ccm and used in offshore racing. The enlarged volume, according to Luigi Guiliani, was achieved by an increased stroke only.

I don't have any real numbers, sorry ...
 

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Aren't the heads v similar to the 4-cyl Nord? Does it therefore follow that you could bore and stroke to 4.0L? Or is the center of rotation and/or stroke of the crank a limiting factor?
 

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I thought it would be of interest to look at the bore and stroke of the factory 3Liters. Here the Montreal Boat racing engine having 86X64,5 mm. As one can see the only difference is increased bore from 80mm to 86mm. This engine was the basis of the Alfetta GTV8 engine which was further tuned to 340-350Hp. The bore and stroke of this engine is similar to the Tipo 33 3L engines with 32 valves.

There was another V8 engine of 4L 32V , also used in the Tipo 33, but reportedly it had a longer block. This engine had 90X78 mm BxS =3969cc 520Hp/10.000 rpm.

In my opinion boring the Montreal engine is the most interesting way to make a 3L. Making a longstroke Montreal engine would be contrary to its heritage!
 

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There's a guy in California that does Montreal big bore work and I cannot think of who it is right now. I'll do some research and get back to you but I think he may north of LA.
 

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I thought it would be of interest to look at the bore and stroke of the factory 3Liters. Here the Montreal Boat racing engine having 86X64,5 mm. As one can see the only difference is increased bore from 80mm to 86mm.
Sorry, but a little off topic: I see in the press release that the weight of the 3.0L V8 is 160 kg. Would it be safe to assume that the standard 2.6L V8 also weighs 160 kg?
 

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Yes, I consider the weight og the Montreal engine to be in this region. From my own experience with the GTV8, it seemed to be lighter in the front than with the V6 engine, weighing about 180Kg.

I consider the blue engine as the 3L boat engine. The blue colour because alu engines need special protecrion against salt water.

The other photo is the 3L in the GTV8, being a development of the boat engine.
 

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Very timely thread this one...I'm currently disassembling a Montreal engine, the owners brief being a minimum of 3 litres, and a good useable 300hp.
I'll keep readers informed and post some pics of the build-up.
Vince.
 

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Will pay attention to you project, Vince! I think the key to success(300+Hp) is what is done to the head, porting, valves etc. Doing this right is dependent of close knowledge to the possibilities of the head.

There is a guy here who has done this already, unfortunately the engine is for racing only so its is not so interesting to use these parts for the road..
 

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As far as I know Dawie from Glenwood Motors has built his own Montreal up with 93mm Milano Verde 12 pistons and an OEM stroke crank...
 

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I respectfully doubt that info, JJ, there really is no place for liners that big in that block. Personally I have heard of 88mm liners/pistons from GTV6 2.5, however normally 86mm is used from factory for 3L.

Some photos of 80 mm and 86mm liner holes in the block. Not much left with the 86mm liners!
 

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