Started eating away at the little hump between both valve guides. First got cylinder 2 then went to 1. Was caught up most of the day so I didn't have the time I would have liked to work on the head.
Unleashing The Beast... (56K Beware!)
- Thread starter MA70witBoost
- Start date
Beals;1615358 said:
Patience you say? Heh, I don't think I'm patient, I'm just hard headed and don't know when to give up.
Ok.. Got all 6 ports done.
Gasket matched the ports, removed the humps between both valve guide humps, then removed the flat spot in the part that separates the valve seats.
Before:
After:
Gasket matched the ports, removed the humps between both valve guide humps, then removed the flat spot in the part that separates the valve seats.
Before:
After:
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On vacation this week. Means no air tools and a lot of free time. Outside at the moment taking measurements for each of the cylinders. Using the pistons to keep my telescoping gauge level as I let it expand. I then lock it in place and measure with my micrometer.
The trick for getting accurate reading is keeping the telescoping gauge straight when measuring with the micrometer. The slightest tilt and the reading are off a couple thousandth.
Cyl 1
T12 - 83.45mm
T3 - 83.5mm
M12 - 83.55mm
M3 - 83.57mm
B12 - 83.5mm
B3 - 83.49mm
Cyl 2
T12 - 83.53mm
T3 83.52mm
M12 - 83.46mm
M3 - 83.53mm
B12 - 83.52mm
B3 - 83.53mm
Cyl 3
T12 - 83.51mm
T3 - 83.53mm
M12 - 83.45mm
M3 - 83.53mm
B12 - 83.5mm
B3 - 83.51mm
Cyl 4
T12 - 83.51mm
T3 - 83.55mm
M12 - 83.55mm
M3 - 83.56mm
B12 - 83.5mm
B3 - 83.55mm
Cyl 5
T12 - 83.49mm
T3 - 83.55mm
M12 - 83.54mm
M3 - 83.55mm
B12 - 83.52mm
B3 - 83.52mm
Cyl 6
T12 - 83.53mm
T3 - 83.46mm
M12 - 83.5mm
M3 - 83.53mm
B12 - 83.54mm
B3 - 83.51mm
Maximum Cylinder Bore Diameter:
O/S 0.50 - 83.74mm (3.2968 in)
The trick for getting accurate reading is keeping the telescoping gauge straight when measuring with the micrometer. The slightest tilt and the reading are off a couple thousandth.
Cyl 1
T12 - 83.45mm
T3 - 83.5mm
M12 - 83.55mm
M3 - 83.57mm
B12 - 83.5mm
B3 - 83.49mm
Cyl 2
T12 - 83.53mm
T3 83.52mm
M12 - 83.46mm
M3 - 83.53mm
B12 - 83.52mm
B3 - 83.53mm
Cyl 3
T12 - 83.51mm
T3 - 83.53mm
M12 - 83.45mm
M3 - 83.53mm
B12 - 83.5mm
B3 - 83.51mm
Cyl 4
T12 - 83.51mm
T3 - 83.55mm
M12 - 83.55mm
M3 - 83.56mm
B12 - 83.5mm
B3 - 83.55mm
Cyl 5
T12 - 83.49mm
T3 - 83.55mm
M12 - 83.54mm
M3 - 83.55mm
B12 - 83.52mm
B3 - 83.52mm
Cyl 6
T12 - 83.53mm
T3 - 83.46mm
M12 - 83.5mm
M3 - 83.53mm
B12 - 83.54mm
B3 - 83.51mm
Maximum Cylinder Bore Diameter:
O/S 0.50 - 83.74mm (3.2968 in)
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Ok, It seems the cylinder bores are within specs. Got to see when I have the chance to pull the short block and disassemble so i can measure the pistons and make sure they are also within specs. All measurements updated up top.
nice dude. looks like you did a great job with that head. wish i had the patience for all of that lol
Looking great. Lots of effort and love in this thread just read the whole 31 pics. Seems like now it will be a bigger beast. Keep up the good work. 
Ok, been talking to Adjuster, and he said that on his motor he took the liberty to remove the valve guide humps. So for the past two days I've been working on that.
Got all 6 ports looking good at the moment, but I'm going to finish up things on the intake side tomorrow.
Taking the exhaust manifold to work tomorrow so I can port that 2mm's then port the exhaust ports on the head 2mm's then polish.
Got all 6 ports looking good at the moment, but I'm going to finish up things on the intake side tomorrow.
Taking the exhaust manifold to work tomorrow so I can port that 2mm's then port the exhaust ports on the head 2mm's then polish.
Ok, intake side is done.
Yesterday:
Today:
Made an outline around the ports on the exhaust side about 2mm out.
Going to start eating away on the exhaust side then port out the turbo manifold in order to keep the reversion dam and maintain the ability to scavenge.
Yesterday:
Today:
Made an outline around the ports on the exhaust side about 2mm out.
Going to start eating away on the exhaust side then port out the turbo manifold in order to keep the reversion dam and maintain the ability to scavenge.
Ok, done porting the intake, exhaust and turbo manifold.
Exhaust manifold before:
After:
Exhaust port diameter:
Before: 31.5mm
After: 33.5mm
Turbo manifold diameter:
Before: 36.3mm
After: 39mm
Gasket diameter: 37.5
Exhaust manifold before:
After:
Exhaust port diameter:
Before: 31.5mm
After: 33.5mm
Turbo manifold diameter:
Before: 36.3mm
After: 39mm
Gasket diameter: 37.5
Been talking to Adjuster and he says he cut the lower part of the valve guides out of the intake ports to keep the ports the same diameter all around.
So that's currently what I'm doing. Progress might be slowed down a bit here at work. My service manager wants me to clock out when I want to work on my head since things are slow. Doesn't want me getting paid hourly for working on my own motor. So more valve guide reduction during lunch.
So that's currently what I'm doing. Progress might be slowed down a bit here at work. My service manager wants me to clock out when I want to work on my head since things are slow. Doesn't want me getting paid hourly for working on my own motor. So more valve guide reduction during lunch.
Ok. Ports are even. Can barely see the valve guides from the manifold side of the intake.
Just a little more cleaning up and exhaust port polishing and were good. =)
Just a little more cleaning up and exhaust port polishing and were good. =)
I've been keeping up with your build thread awhile, good to see some hands on head work.
Its like your cooking up a recipe I've never had before with the level of head work your doing.
I can't wait to see how it turns out!!
Its like your cooking up a recipe I've never had before with the level of head work your doing.
I can't wait to see how it turns out!!
thedave925;1621016 said:
Well im guessing the motor I got from 5Leater had a bottom end rebuild only. No head work was ever done. Hence the valve stem seal problem. I really didn't want to have to deal with a machine shop. Wanted to do all the work myself. But there ya go. Since I have to disassemble the motor to fix the bearing problem I figured "why not build the head and have a fully built motor?"
That being said, I was stumbling around SM today and ran into a thread that mentioned the factory head thickness being 116mm's. It got me curiouse. Seeing as i still dont fully know the history of this motor, I decided to borrow my co-worker Alain's Matco Micrometer to measure the height of the head. It measured out to 115.48mm's. I was asking around and as per the other techs the head gets resurfaced more than the bottom end does. So it leads me to think that this 7M hasn't seem much machine work. Maybe the one bottom end rebuild and thats it. Im hopeing that means it'll be easy to maintain factory compression. Also, hopefuly with this next rebuild I shouldn't have anymore problems.
Ok, I couldn't resist myself. It's been a while since I've bought anything for the supra and I had some money burning a hole in my pocket. Nothing out of this world but ordered a set of Beech Quick Disconnect Sway Bar Links for the rear sway bar on my car. The first set I got (wich was from MDC Motorsports I think it was) had all broken. I got a set of the Beech ones and tested em on the front of the supra for a bit. Fortunately they haven't broken so I figured it was about time for a set of links for the rear instead of not having anything back there. Also took the liberty to order a set of machined EGR Block-Off plates to replace the crummy looking piece of metal and silicone that's on the back of my head and side of the intake manifold.
Looking to purchace a set of 1mm+ Ferrea Valves hopefuly this friday if the pay is there and going to find out about sending my cams to get reground to 264's. More info on this later.
Looking to purchace a set of 1mm+ Ferrea Valves hopefuly this friday if the pay is there and going to find out about sending my cams to get reground to 264's. More info on this later.
MA70witBoost;1620611 said:Been talking to Adjuster and he says he cut the lower part of the valve guides out of the intake ports to keep the ports the same diameter all around.
So that's currently what I'm doing. Progress might be slowed down a bit here at work. My service manager wants me to clock out when I want to work on my head since things are slow. Doesn't want me getting paid hourly for working on my own motor. So more valve guide reduction during lunch.
Hope you DIDN'T take Greg's advice on this one.....
What are you talking about Ian? If you are talking about cutting the valve stems, yes i did. What did i F@$K up now?IJ.;1622501 said:
IJ. said:
Ok... Didn't really mess anything up, just slightly shortened the life of the valve seats...
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Ok, port and polish are roughly done. Things have been a bit hectic for the past week or so. I was laid off in the end of October and the same day I was laid off the head gasket finished going on my Nissan 240SX. Applied for unemployment and am waiting for that. Been busy with disassembling the KA24, fought with the intake manifold a bit and pretty much almost got the head off. The daily driver has to come first altho I hate working on the 240 and not the Supra. Pending the repair of the DD and some money I'll get to ordering parts for the 7M.
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