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My na motor is going bad so I'm planning on pulling it out soon. My plan is to build the 5S from top to bottom, but what i want to do is use stronger internals so the motor can take a beating for the next 100k+ miles. Power is not important because I like to take the curves. Can someone give me recommendations on what internals to use and also any machine work needed to the block and head. Thanks.

Rui.
 

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What is your budget cause we could sit here all day telling you things you need for durabuility...What TomsMR2 said it correct for a low budget semi reliable rebuild. To make it more "durable" so to speak you would need to add some sort of EMS.
 

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Also what are the symptoms your engine has that tell you it's about gone? For durability the stock components were designed to go 200,000+ if you don't abuse them and change the oil regularly.

When rebuilding with durability in mind make sure you use moly rings, they are ~$80, it's what the motor came with from the factory and alot of aftermarkets rings are crap and will only go 50,000 miles before wearing out. Have the block tanked and thuroughly cleaned and then bored out 0.020" over to take out any previous wear. They don't need to use a torque plate on the 5sfe because the head bolt holes are far enough away from the cylinders that it doesn't deform more then about 0.001" but if the shop has one that fits, do it. Then you will need 0.020" oversized pistons. You can get 0.020" oversized idenitcal to the stock ones for ~$60. Next have them grind the crank, rods and caps to whatever it takes to remove any previous wear. Get oversized bearings and new thrust washers. Get new rod bolts from Toyota. When the shop machines the rods they will need the bolts to do it but ask them not to torque them all the way down. The stock bolts are torque to yield so you crank them down to like 24lbs then 90 degrees more and they stretch. You don't want to do the second step and stretch them until final installation. Pretty much all the bolts and studs are this way in the 5s block. You can use 3sgte ARP main studs and 3sgte ARP head studs in the 5sfe but one of the head studs needs to be shortened. These are not torque to yield so they will need to be retorqued after the engine has been warmed up and things settle in but they are stronger bolts.

For the head, verify that all the mating surfaces are true and have them machined if not. Have a 3 angle valve job done and replace all the valves seals. Go through the BGB and check all the clearances and spring pressures. Oversized valves and CAMs will give you more power and more into the higher RPMs but really aren't going to make it more durable. Replace all the seals and gaskets on the head. You can buy kits that have everything included.

Lastly replace anything that is known to fail over time like timing belt, water pump and oil pump. For the oil pump use one made for a 97+ 5sfe because the have better flow.

I'm sure there's something I forgot but that should be a good start. :)
 

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For the oil pump use one made for a 97+ 5sfe because the have better flow.
interesting.. i know the 3sgte pump flows.. but im reluctant to put a pump intended for a motor with a turbo hanging off it on an na... is the later 5s pump the same part as the 3s pump, or is it kinda a happy medium? it would be nice to have a bit more flow, just incase.
 

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The oil pumps are interchangable. It's funny because many of the 3sgte guys are putting the 97+ 5sfe pump in their cars and shimming the relief valve by 1.25mm to get even more flow. :) This info comes from mister3 and chrisK so if you want more details do a search on "high volume oil pump".
 

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Wow, thats pretty good information Mrturrari. I'm a little disappointed I didn't know about the ARP bolt option when I did my rebuild.
 
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