Last week I talked to Advance Motor Mechanics (they'll be doing the rebuild) and I asked them to pull the engine out and strip it down when they get a chance, then they'll let me know the condition of my block, pistons, rods, etc. I realised that I shouldn't commit to anything until this happens.
If the existing internals need to be replaced anyway for whatever reason, then I'll definitely do the full 5S-GTE upgrade, but if they're still OK then I'll be able to make a choice of how far to go with it.
I'm just going to put some summary notes here for my own info, but it will be beneficial to others as well.
Standard 3S-GTE crank/block/pistons:
86mm bore, 86mm stroke = 1998cc displacement
3S-GTE crank/block/pistons (with 0.5mm overbore) (this is what I have now):
86.5mm bore, 86mm stroke = 2021cc displacement
Standard 5S-FE crank/block/pistons:
87mm bore, 91mm stroke = 2164cc displacement
5S-FE crank/block/pistons (with 0.5mm overbore):
87.5mm bore, 91mm stroke = 2189cc displacement
Hybrid with 5S-FE crank, 3S-GTE block, and custom pistons to suit 5S stroke and 3S bore (with 0.5mm overbore):
86.5mm bore, 91mm stroke = 2139cc displacement
^This is a 'middle ground' with ~120cc increase in displacement due to the 5S stroke, but without the increased bore of the 5S block.
- 3S and 5S blocks have the same height from the crank centre line to the top of the block, but 3S and 5S rods have the same centre-to-centre length of 138mm, therefore the wrist pin is 2.5mm higher in the piston when using a 5S crank.
- 3S rods have a smaller big end diameter than 5S rods, so the crank has to be machined accordingly if using 3S rods with a 5S crank. Not a big deal.
Displacement is one factor, but another is block strength.
Cost if obviously a major factor too, but its flexibility will depend on the condition of my existing internals.
The consensus seems to be that the 97-98 5S-FE block is the strongest. However, apart from the reinforcement of the block near the water pump, wouldn't the 5S block be weaker than the 3S block in other places due to the bigger cylinder bores?
post edited by robk - 2017/12/12 15:49:53