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temperacerguy
07-30-2011, 10:19 AM
OK, I've searched the net and there's a whole bunch of "Internet experts" giving incorrect and opposing data out there...

Does anyone know the actual real, bottom dollar, 100% correct TRUE answer for these?

1st:What are the Deck Heights for the 3S and the 5S blocks?

2nd: Does the 5S block have the same location for the cross block oil gallery that the 3S has for the piston oil squirters? IE, can the 5S Block be machined to include these?

Thank you,

Sang
07-30-2011, 02:16 PM
Totenkopf (or maybe it was Bob Hatton?) is doing the same thing you want it seems. He machined, drilled and tapped for oil quirters on his 5S block. Detailed pics are on mr2oc.com. And I've never done an actual measurement on deck height, but they are the same for both 3S and 5S

Sang
07-30-2011, 02:18 PM
http://mr2oc.com/showthread.php?t=426064&highlight=oil+squirters

temperacerguy
07-30-2011, 04:22 PM
Thanks for the link to the oil squirters....

here are threads saying the deck heights are different again, why I want numbers:

http://www.toyotanation.com/forum/archive/index.php/t-32543.html
http://www.alltrac.net/phpBB2/viewtopic.php?f=7&t=41176
http://www.6gc.net/forums/lofiversion/index.php?t42830.html
http://mr2oc.com/showthread.php?t=427462&highlight=5s+deck+height

Sang
07-30-2011, 11:38 PM
That last link actually says they are the same.

If you notice, all the links that say it is not the same are not from mr2oc. No offense to other forums, but as far as good technical information is concerned, mr2oc.com is the place to go. The mr2 board isn't nearly as far a long as other car communities as far innovation, but the OC is the furthest along of the 3sgte based message boards.

Especially toyotanation...I used to go there but every other thread I read was just a facepalm.

temperacerguy
07-31-2011, 06:20 AM
cool, ok, so what's the deck height? I'm looking for numbers

klapa
07-31-2011, 06:42 PM
I know what deck height IS - but where is the reference point for the measurement?

Is it the distance from the center of the crank to the top of the deck?

temperacerguy
07-31-2011, 10:27 PM
Deck height is always measured from the centerline of the crank to the mating surface of the head. (BTW) in the last thread listed there (on MR2oc), he's not measuring deck height, he's measuring crank CL to top of piston. This is not the deck height, it's also done with aftermarket rods/pistons which it has been proven in the aftermarket that there is variance in rod length and compression height of the pistons from their stock counterparts.

klapa
07-31-2011, 11:27 PM
Deck height is always measured from the centerline of the crank to the mating surface of the head. (BTW) in the last thread listed there (on MR2oc), he's not measuring deck height, he's measuring crank CL to top of piston. This is not the deck height, it's also done with aftermarket rods/pistons which it has been proven in the aftermarket that there is variance in rod length and compression height of the pistons from their stock counterparts.

Thanks for the info - I knew that the "top of the deck" IS the mating surface for the head on the block - just did not know for sure the reference point (centerline of the crank) for the measurement. I had thought about the fact that perhaps you could calculate the deck height based on the stroke. Surely - different pistons will have different heights to the crown for the same stroke - so that would be a "variable" while the deck height for any specific engine would always be the same.

temperacerguy
07-31-2011, 11:42 PM
The reason I stated "mating surface for the head" instead of "top of deck" is because while for an Inline engine like this, they are synonymous, however with a flat, or V engine, the deck height is not the top of the block.

ChrisD
08-02-2011, 04:17 AM
Are you looking to have custom rods done or something? There's a tonne of info on what parts make the combo work. You could always call ATS and ask what to use for your setup, and just get the parts through them.

MrTurrari
08-02-2011, 05:24 AM
Every reliable source I have talked to has always measured deck height as the distance from the top of the piston when it is balanced in the cylinder to the top of the deck of the block. I suppose there could be other people out there who use that description for something else but I haven't ever seen it. For both 5s and 3s engines this will depend on how much the block has been machined to eliminate low spots or warpage. They start very close to zero from the factory though. Last one I measured was within 0.005".

If you need the crank centerline to deck distance you will need to find the piston pin height or also called the compression height. On a 5sfe that is about 1.275" or 32.36mm. If you take half the stroke plus the rod length plus the compression height you get the distance from the centerline of the crank to the deck (within a few thousandths). I do know that the 3sgte and 5sfe share the same rod length within 0.005" so if you can get a 3sgte piston to measure you can figure it out. The rods are both about 5.433" or 138mm.

So why do you need to know this?

Sang
08-03-2011, 02:12 PM
Every reliable source I have talked to has always measured deck height as the distance from the top of the piston when it is balanced in the cylinder to the top of the deck of the block

This is how I know deck height to be as well.

temperacerguy
08-04-2011, 05:19 AM
I'm going to be building a custom stroker engine. I need to know what the deck height is so I can figure the quench clearance for the custom pistons I am having made. I am also looking if I can reduce the compression height of the piston further to get a longer rod for a slightly better rod ratio.

MrTurrari
08-10-2011, 06:44 PM
I would keep the quench height right around 1mm like stock (thickness of the head gasket basically). The amount you could move up before risking contact under high RPMs is so small it won't make much of a difference in the rod ratio.

For increasing the rod ratio you have a couple of choices. Have the pistons made with the pin higher up, they can even make pistons where the oil rings go over the pin location, or use a thicker head gasket and have a positive deck height keeping your quench still at about 1mm. I would have a talk with whoever is going to be making your pistons and see what they can do. If you want a recommendation then I would talk to Nick Arias at atomicspeedware.com. You are also going to need a custom rod but I assume you have already thought of that. :)