Building a 1fz-fe for light boost dd. Need advice (1 Viewer)

[cruiserbrandon]

Hey Mud guys, been on here for a coupe years and built a 60 that is still in progress as well as lurked and commented where I could, now I need some advice.

So I bought an lx450 for a family rig/daily driver/tow rig with a rod hanging out of it and bought a donor motor to build. I am a lead tech and have plenty of complete builds under my belt but there are some inherent questions I have about the 1fz.

Main bearing cap bolts and rod cap bolts both are a torque to yield (torque to spec then stretch 90 degrees) now all my experience with tty head bolts are replace them, or some manufactures have a 2nd and 3rd time torque to yield spec for already stretched. No info in Mithel or alldata has any specs nor do they say to replace the bolts. What is protocol for these bolts, Replace or just torque and call it good? If I reuse them, how many times can they be stretched?

Second question is about cometic head gaskets. I had the machine shop bore the block and machine the head but he was hesitant about decking the block because he could not find specs and didnt want a piston sticking out too far so he wouldnt touch it. My mistake was I installed the bottom end before inspecting the block surface and when I went to clean up I notice some pretty deep corrosion around water jacket behind 6 and in front of 1. Research said to take a flat block or something to keep the surface flat and lightly sand with emry cloth, I did a couple test runs with this trying to take off very little at a time and really watch what I am doing but it just doesnt feel right, plus all the contaminants are gonna end up in my brand new bottom end. Hence the question in the first paragraph about the mains and rods being torque multiple times. I dont want to cheap out and want it done right. As I sand I keep taking a straight edge and checking down to .002 and so far its going very well it just doesnt feel right. Maybe someone has specs of how much can be taken off the block in case things go south I can give the machine shop a number to ease his mind.

Thoughts and suggestions? Any interest in seeing the build? I figure there are butt loads of 1fz builds on here so I wasnt too worried but I can throw some stuff up here if anybody wants.

 

[scottryana]

If you are building for boost. Replace the TTY head and main bolts with ARP studs. You will need to trim a couple of the studs to clear the oil pan when used as main bolts.

Do not use a Cometic head gasket unless both the block and the head have been machined to an almost mirror like shine it just won't seal properly. It sounds like you definitely need to have your block cleaned up. If you can feel the problems in the block surface with your fingers, usually catching a fingernail it needs to be surfaced regardless.

I would either find another machine shop that could examine the block and tell you how much would need to be taken off the block to clean it up or if you really want to proceed the way you are, you would have the most luck with an OEM head gasket since it will have a little give in the sealing surface but I wouldn't be surprised if the longevity is slightly compromised.

 

[cruiserbrandon]

Im talking 5-7 lbs of boost, nothing crazy, is it still necessary to go main bearing studs instead of reuse the bolts for something that minor?

The only other machine shop is 2 hours away one way. Not much to choose from around here.

The cleanup that I need to do is probabaly less than .004 to get perfectly smooth, If I continue to do the emry cloth and can get it mirror like finish would that be acceptable? What is the rule for cometic in terms of block being true, would within 2 thousands be ok like I shoot for on block cleanup head gasket jobs I do?

Finally when I pull it back apart will I need to replace the main bearing bolts if they are ok for light boost applications as well as rod studs. Or can they be torqued multiple times?

 

[scottryana]

No it isn't necessary but I think the ARP studs are cheaper than new TTY Toyota bolts. Choose your poison. Usually I recommend OEM parts, but with ARP studs being cheaper I would lean that way. But if you had it machined with bolts you need to stick to bolts.

Cometic recommends completely flat surfaces with an RA finish less than 50RA.

Im talking 5-7 lbs of boost, nothing crazy, is it still necessary to go main bearing studs instead of reuse the bolts for something that minor?

The only other machine shop is 2 hours away one way. Not much to choose from around here.

The cleanup that I need to do is probabaly less than .004 to get perfectly smooth, If I continue to do the emry cloth and can get it mirror like finish would that be acceptable? What is the rule for cometic in terms of block being true, would within 2 thousands be ok like I shoot for on block cleanup head gasket jobs I do?

Finally when I pull it back apart will I need to replace the main bearing bolts if they are ok for light boost applications as well as rod studs. Or can they be torqued multiple times?

 

[cruiserbrandon]

Bottom end did not get machined, everything was like brand new, just polished crank and new bearings. I may look into studs then for the bottom end, as for the top since I already have the bottom end In I never considered just spinning it to tdc and measuring to see how much could be taken off the block and just report that to the builder, make sure its dont right. I already have arp head studs and cometic head gasket so I really want to go that route.

 

[cruiserbrandon]

Well after measuring the piston to block clearance and realizing there are so many thicknesses of head gaskets I talked to the local machine shop and we came to agreement there is plenty of meat on the block to have it decked. In fact I have over .020 that could be taken off with the head gasket that I already purchased and still have the .035 required clearance for expansion and contraction from heat. So took it back apart yesterday and gonna have it decked so its done right, then I can clean up the bottom end again real well and get some studs for the lower caps. I talked with Brian Crower and they said the factory bolts are acutally more than strong enough to handle about anything you can throw at them but since they have been installed already they suggested I replace them and then informed me of $20 a piece for new factory bolts, when the studs are like 140 for an entire set. Obviously the logical choice is put studs.

One more question if anyone knows, where can I look up the compression ratio and amount of change that taking .005 off the head, probably .005 off the block and a .040 compressed head gasket will be?