1FZ-FE Cylinder Head Questions
- Thread starter John Goodyear
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The baking of the head to flatten it had to do with a controlled cooling of the head. I've never done it but I have heard of good results.
As for prepping the surface, there is a spec for surface irregularity but very few machine shops actually have an accurate surface irregularity gauge.
My rule of thumb is to make sure the surface is clean of any material or fluids and check for cracks or deck damage. If it checks out then reinstall it. If I need more compression I use a thinner gasket rather than machine the head surface.
As for prepping the surface, there is a spec for surface irregularity but very few machine shops actually have an accurate surface irregularity gauge.
My rule of thumb is to make sure the surface is clean of any material or fluids and check for cracks or deck damage. If it checks out then reinstall it. If I need more compression I use a thinner gasket rather than machine the head surface.
Is there any other process than can be done to further identify cracks or other hidden flaws that can be to an aluminum head other than visual inspection?
Anyone out there have a serious objection or think we are headed for failure if we follow my current inclination to get some arp studs and let them pull the head back down like Chitown mentioned?
Guys we need machine shops. We are not finding to much local. Any know cruiser shops that can do the heating process? Any known shops with the surface irregularity gauges? Any rebuilders to just swap out to a finished ready to bolt on head? Sorry been out of the cruiser scene for a while so we might not know a vendor that everyone here might think is common knowledge.
TNX,
J
I think the machine shops use a dye to determine if there are cracks in the head. You just spray it on and it works its way into any irregularities, making them stand out.
I'd imagine you can find videos, but on other heads I wire wheel any carbon between the valve head and stem then compound on the valve-hand suction cup tool back and forth until even lapping on seat and valve then clean. Would take a fancy spring compressor to dissasemble these. I used a big v-8 compressor and 3/4" pipe coupler as an extension to the retainer.
That only works for combustion chambers the way most machine shops do it.
As for the ARP studs use the 2jz supra kit. Set the stud depth by leaving at least 1 thread above the top of the nut, any more is a waste of possible engagement in the block. Use red thread lock on the block side, let stand to keep the stud from turning while tightening. Torque spec is 80 ft/lbs in three steps in factory sequence.
Thank you very much Chitown! We will get them. How many of these ifzfe heads have you done like this? Ever have one that did not come back to shape causing a second gasket failure? I really want to follow your lead but that nagging feeling keeps coming back to me saying there is no way we want to do this job again.
If you don't want to do the job again then perhaps you should get a head that isn't warped. I'm not saying this won't work, but if you are really worried about it why cut corners ?
Had a 280Z head straightened like this years ago with no problems. I'm sure this technology has been around for decades and is not "experimental" or "shortcutting" . search it or check with the machine shop. Don't neccesarily have to be 1fze head expert for this work.
I have to agree with NLXTACY on this one.
Pay for quality skilled labor to have the head reman'd. I went the "less expensive" route in my past and by the time I was done, it cost me an additional $1500 because the jackhole that did my heads didn't do them correctly and I ended up flooding a cylinder with coolant and hydraulic'd the cylinder, bent the rod, caused me to pull the engine and rebuild and balance it AGAIN in addition to the cost of a new rod and piston, and then new heads (the previous ones were ported, polished, and matched). If the head is warped too much, find a different one. They will still have to clean up the valves and do a crack check. And the proper term is to do a Dye-Penetrant test on an aluminum head as well as pressure test. A pressure test is not always accurate because the head is not at operating temperature and the crack may not be open. That's why a DP test is used.
Pay for quality skilled labor to have the head reman'd. I went the "less expensive" route in my past and by the time I was done, it cost me an additional $1500 because the jackhole that did my heads didn't do them correctly and I ended up flooding a cylinder with coolant and hydraulic'd the cylinder, bent the rod, caused me to pull the engine and rebuild and balance it AGAIN in addition to the cost of a new rod and piston, and then new heads (the previous ones were ported, polished, and matched). If the head is warped too much, find a different one. They will still have to clean up the valves and do a crack check. And the proper term is to do a Dye-Penetrant test on an aluminum head as well as pressure test. A pressure test is not always accurate because the head is not at operating temperature and the crack may not be open. That's why a DP test is used.
He's not talking about heating and bending the head back to flat. He is now talking about using ARP studs or head bolts and trying to force the head back flat by bolting it down hard.
Roughly 3 or 4 dozen (sorry lost exact count over the last 20 years) head gaskets including a few that make in the 4 digit hp range.
There's a reason there is a loosening sequence and a tightening sequence, Toyota knows you can't have a slab of aluminum heat cycled a few million times with out twisting so they wrote the service procedure to take that into account.
As for the ARP studs, I would use them in my lawnmower if they made a set lol. I know the guys at ARP and have had long conversations about how studs don't have to be bottomed out. In fact they make a special stud with a "nub" for those sets that need to be bottomed out. Make sure the threads are clean and allow the thread lock to set up before torquing and use lots of ARP's grease on the washers and nuts and you'll be fine.
There's a reason there is a loosening sequence and a tightening sequence, Toyota knows you can't have a slab of aluminum heat cycled a few million times with out twisting so they wrote the service procedure to take that into account.
As for the ARP studs, I would use them in my lawnmower if they made a set lol. I know the guys at ARP and have had long conversations about how studs don't have to be bottomed out. In fact they make a special stud with a "nub" for those sets that need to be bottomed out. Make sure the threads are clean and allow the thread lock to set up before torquing and use lots of ARP's grease on the washers and nuts and you'll be fine.
Thank you everyone for your commentsand happy 4th of July! We still have not found a machine shop that can handle the described procedure nor a vendor for a fully rebuilt head. We have purchased valve lapping tools and compound should we give up on machine shop / another head.
Are you trying to find a place to try and un-twist the head? They are extremely rare. If that is still your major concern have you thought about purchasing a new head casting and swapping over your valve train?