5S-FE block + 3S-GTE head?

[topgear]

Hello guys,

I was just wondering if i could use a 3S-GTE crank on the 5S-FE crank.Using the 5S-FE crank will increase your stroke but it will also increase piston acceleration(stressful on the bottom end).

The advantage on the 5S-FE block is its stock bore is already 87mm(vs. 3S-GTE's 86)meaning to say that 1mm oversize to 88mm will be quite safe.Do they share the same main journal diameter?Is the 5S-FE block taller than the 3S-GTE?I read somewhere that long rods are good?what are the advantages?

Does the 5S-FE share the same sub systems on the short block with the 3S-GTE?

Lastly,how much hp does the stock GT4 tranny will take?Is there any TRD(or cheaper alternative to it)gearsets that can handle huge hps?


Im asking you guys this Qs cause im planning a 3S-GTE project in the near future...



I hope to hear from you guys soon.thanks.

[adam_celica]

First of all, the 3SGTE main journal size is not the same as the 5SFE, and the 5SFE crankshaft has a 91 mm stroke, where the 3SGTE has something like 86mm. When it comes to high-performance, the longer the stroke the better, and that goes for pretty well any application, especially turbo. I don't know where you heard that a longer stroke is bad for the bottom end of an engine, but it's really not true. In fact, a shorter stroke accomodates higher RPM's and so you could say that shorter stroke is actually worse for the bottom end of an engine. I really don't know about deck height from one to the other, but that's irrelevant because a custom piston could be made with the wrist pin height adjusted to wherever it needs to be. Long connecting rods are better than short because you decrease the angle of the rod, lessening the pressure on what's called the thrust side of the piston. This in turn decreases friction and wear, you actually will gain small amounts of horsepower by increasing connecting rod length, but it's more used for longevity purposes. I don't know what you mean by sub-systems, but I imagine it's things like an oil pan and pickup tube. I doubt they do, but I don't know for sure. Most turbo oil pans have a fitting on them to run directly from the turbo, but again, I'm not sure that's the case with the 3SGTE. The trick thing to do would be to stroke the 3SGTE with a 5SFE crankshaft. That's obviously not easy though, you'd need to either machine the crankshaft or have it welded and then machined to fit into the main bores in a 3SGTE block. Then you would have to do a mock assembly and clearance the 3S block, and you'd need to order pistons with a lower pin height, plus, you'd have to now balance the engine to the new crankshaft (and that may not even be possible). Getting more stroke into a turbo engine is ideal because takes up some of the slack that turbo lag can leave, giving you more torque off the line until your turbo spools up. As for the transmission question I really have no idea.