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VVT Head removal

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Old 05-10-2018, 08:46 PM
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Default VVT Head removal

I just picked up an '02 VVT engine which died due to overheating. I'd like to build this engine so as not to take my car out of service while,I build. Not my daily driver and I'm in no hurry.

My my first concern due to the overheating, is the head. I have never removed a VVT head and don't want to do anything out of sequence with respect to the VVT actuator. Can it be pulled off together with the valve cover? Pull it first? Is it all obvious as I do it? Recommended procedure for testing, then servicing the head. My power goals are in the ballpark of 250-275 rwhp with serious reliability. I have an FM2 kit managed with a Hydra 2.7.

Build ideas are:
Forged pistons and rods 8.5:1 compression ratio.
Coolant reroute with pre VVT head gasket.
Head to remain essentially stock? I don't feel the need for 7400 + rpm.
Oil pump and damper? If not revving higher than 7400 ish will new OEM serve me? Do I need to go Boundary oil pump Supertech damper?
Goal is stated power with long life expectancy for fast street driven and autocrossed car.

Returning to first question, anything I can screw up with valve cover and head removal?

Thanks,
Paul
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Old 05-10-2018, 10:55 PM
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Originally Posted by pmhellings
I just picked up an '02 VVT engine which died due to overheating. I'd like to build this engine so as not to take my car out of service while,I build. Not my daily driver and I'm in no hurry.

My my first concern due to the overheating, is the head. I have never removed a VVT head and don't want to do anything out of sequence with respect to the VVT actuator. Can it be pulled off together with the valve cover? Pull it first? Is it all obvious as I do it? Recommended procedure for testing, then servicing the head. My power goals are in the ballpark of 250-275 rwhp with serious reliability. I have an FM2 kit managed with a Hydra 2.7.

Build ideas are:
Forged pistons and rods 8.5:1 compression ratio.
Coolant reroute with pre VVT head gasket.
Head to remain essentially stock? I don't feel the need for 7400 + rpm.
Oil pump and damper? If not revving higher than 7400 ish will new OEM serve me? Do I need to go Boundary oil pump Supertech damper?
Goal is stated power with long life expectancy for fast street driven and autocrossed car.

Returning to first question, anything I can screw up with valve cover and head removal?

Thanks,
Paul
nothing special, remove vvt solenoid, remove valve cover, unbolt head with the correct bolt sequence.

make sure to have a machine shop check head for flatness and deck it if needed, due to overheating.

the rest of the build sounds good to me.
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Old 05-10-2018, 11:04 PM
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I go one step further and only remove the banjo bolt in the back. Takes a little force to get the housing off the 2 o-rings, but that's like saying 5-30 oil is significantly different than...5-31
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Old 05-11-2018, 12:36 AM
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Originally Posted by pmhellings
I just picked up an '02 VVT engine which died due to overheating.
50/50 shot the head is trash. You cannot simply deck the head back to flatness, and if you try to heat and straighten, it will be highly susceptible to warping in the future.

Our built motor program rejects zero-compression overheated cores. I would not even use one in my own car.
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Old 05-11-2018, 12:47 AM
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Good to know. Avoid overheated cores. Thanks Andrew.

Edit: is there any obvious visual sign that the engine has overheated if you're buying an engine already out of car from CL ?
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Old 05-11-2018, 07:02 AM
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Originally Posted by Savington
50/50 shot the head is trash. You cannot simply deck the head back to flatness, and if you try to heat and straighten, it will be highly susceptible to warping in the future.

Our built motor program rejects zero-compression overheated cores. I would not even use one in my own car.
Thanks for the info. Will a decent shop be able to tell me if the head is usable?

Paul
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Old 05-11-2018, 07:05 AM
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Originally Posted by phocup
Good to know. Avoid overheated cores. Thanks Andrew.

Edit: is there any obvious visual sign that the engine has overheated if you're buying an engine already out of car from CL ?
I got the engine from someone in my local Miata Club. He told me about the overheating. One sign might be pulling the Coil pack / plug wires. The one on #4 is deformed.. I'm hoping this head isn't a loss, but I didn't put much $ into the engine.

Paul
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Old 05-11-2018, 09:24 AM
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A decent machine shop should tell you. With mine unbolted, the cams had spots that were difficult to rotate, indicating the bores were warped. That head is now aidan’s Manifold jig
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