I think to much some slap me, 3s < 5s Options

[macavely]

Ok so toyota has the 3s block which is a great one we all know this .. but see as its te 3th make of the S block wouldn't the 5S be a better block ? ... why would toyota make the 5 th version of the block weeker then that of the 3rd? .... and while at it why would the internals be weaker ? it just would make any senne for toyota to not move up .. and keep there "toyota is for ever " thing going ... and then why would they put the 5S in so many cars and in the one that they sell the most ? unless it can take abuse like a pro ? then i'm thinkin my eingine has 221,XXX K miles on it and she is still strong ... and doesn't burn oil ? now what i want to try is doing is fine and camary with the SS and boost it the right way and see how much before it will blow up ....

[Galcobar]

The block is determined by the second digit in the engine code: S block, M block, etc.

The preceeding number is the generation of the engine using that block. The 5SFE is therefore the fifth engine type to use the S block.

The reason the 3SGE is better than the 5SFE has nothing to do with the block per se. It is the head geometry, reflected by the F or G. F is a narrow valve-angle head aimed at producing a more torque-oriented engine with low-end power for drivability and fuel economy. The G head is a wider angle, encouraging higher RPMs and thus higher HP peaks, with a greater overall output.

The internals in the F-head engines are always lighter than in the G-head engines because they don't have to handle as much stress and, being lighter, encourage fuel economy. They last just as long as the internals of a G-head engine because their lighter build is matched to a lighter load. This would be why a 5SFE can never match a 3SGE's potential, particularly under boost, even though it has greater displacement -- it would break.

I would, however, love for someone to explain how replacing a crank increases displacement, since it's the size of the combustion chambers contained in the head which determine displacement.

[bigblock261]

I would, however, love for someone to explain how replacing a crank increases displacement, since it's the size of the combustion chambers contained in the head which determine displacement.
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Just for the record, plain and simple, the displacement of an engine is determined by the volume of the cylinders that are swept by the pistons. Bore and stroke. Pistons and crankshaft. For 4 cylinders the formula is: bore x bore x stroke x 3.141592654 (pi).

As has been discussed, changing to a crank with a longer stroke will increase displacement, but the pistons and/or rods also have to be changed to address piston height dimension conditions, meaning the piston can travel lower into the bore but not higher than stock. A stroker kit solves all these issues.

Now, compression ratio IS determined by the size of the combustion chamber. Small chambers equal high compression.