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What does ARP say? All the studs I have worked with were only installed finger tight? I did not think they were suppose to bottom out in the hole?
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ARP doesn't really care as long as you maintain the 2.5:1 thread length to width rule of thumb for steel studs in aluminum. In this case, the I have 10MM in stud width and 24.5mm in thread engagement length on the stud. I'm calling that close enough as far as the rule of thumb goes.
I'm just not sure from an overall structural integrity viewpoint which would be stronger and more reliable. That said, I'm leaning toward the ARP studs. Especially since the M11 head studs only have 29mm of thread engagement length. FYI, as I understand it, ARP's "standard" engagement lengths are typically either 1" or 1.25" on their studs in these size ranges. (It may be different for other sizes, I don't know)
I did not have the block machined for the M10 main studs. Honestly I didn't put much thought into it beyond those being the studs that ARP recommended - which apparently aren't available any more anyway.
I must confess at this point I'm like it runs great, including when being truly spanked, so if the thread engagement isn't enough I feel like I would've found out by now
I did not have the block machined for the M10 main studs. Honestly I didn't put much thought into it beyond those being the studs that ARP recommended - which apparently aren't available any more anyway.
I must confess at this point I'm like it runs great, including when being truly spanked, so if the thread engagement isn't enough I feel like I would've found out by now
I really can't argue with your logic! With a little luck I too will look back and say, "It sure runs great!"
Hey @davetibbs I've got another "curiosity" question for ya!
While my engine is down at the machine shop, I needed to put the rotating assembly together for balancing. After reading the piston orientation portion of the manual, I got confused. Full disclosure, like an idiot, I only took pictures of the pistons on one bank of the engine, and not the other.
According to the manual, the pistons always orient the arrow pointing forward. The problem I have is the fact that if the arrow is always pointing to the front of the engine, the pistons in one bank will basically be 180 degrees out from the other bank.
While the pistons are for the most part symmetrical, they're not. The valve grooves on each side are different. I can only assume one set of grooves is machined for the intake valves, and one set is machined for the exhaust valves. By keeping the arrow pointing forward, the valve grooves invert from one bank to the other.....unless I missed something.
New piston with markings
Another full disclosure, I purchased these from Apex auto in the UK, who sourced them from China. They say "Genuine Parts" but I have my doubts. lol!
This is the one of the pics I took of the engine before I removed the rotating assemble. (FYI its the right bank with the front of the engine located at the bottom of the pic.
Right bank, front of engine is down
I feel like I have to be crazy and am over thinking this....but I REALLY don't want to slap a valve!
Oh yeah, one other silly question, has anyone found part numbers/where to buy new valve guides? I have new valve seals, but can't track down the valve guide part numbers.
Interesting question. Yes, the engine manual states all arrows point forward, and IIRC I reassembled mine following this. My suggestion would be searching google images/ebay to see if you can find any other pictures of short blocks (incuding Range Rover Sport Supercharged etc), although these can often be tough to find with decent resolution/close up etc.
I wasn't able to source valve guides - I assume a decent enough engine shop might be able to.
Pistons always are fitted with arrows to the engine front. Your pistons look like mine did and look symmetrical to me. Here are a couple of pics of one of my assembled engines. I think you are overthinking it, these are clearance pockets after all. It is important to get the rods fitted the correct way in each bank though. And yes,some of the pistons had already touched in the blowup.
You won't get valve guides but there is a guide available from a different engine that is the same ID and OD but slightly longer. It can be shortened. Nolands cylinder head shop (816-471-5167) in Kansas City sold me some. They do all the repairs for the local Jag dealer and have fixed a bunch of 5.0 heads.
One of my heads before and after.......
Last edited by kansanbrit; Feb 20, 2022 at 07:58 AM.
Nice pics. While we're on the subject of heads, is it me, or is finding used supercharged heads with cams for an even vaguely reasonable price quite a challenge? At least on eBay etc. I quite fancied getting a spare set to have ported and flowed but at that price I may as well just do it to my existing ones and have the car off the road for a bit.
OMG what a mess!
That ain't gonna grow back...
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it runs great, including when being truly spanked, so if the thread engagement isn't enough I feel like I would've found out by now 
