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Starting this thread here as I'm going to have a alot of question and need some fellow tech members input as I go. Went with ARP main studs this time around. Yes machine shop align honed the block with the new studs.
Got the block back from machine shop and it was decked, honed to 4.070 and mains align honed. K1 crank with king main bearings. Main bearing clearances are between. 0020-.0021. Little loose but i think id rather have lower oil pressure than having a chance of oil break down and grabbing a bearing and spinning. Wiseco -8cc pistons where selected to help keep compression under control with the 61cc heads. Piston specs
Rod bearings are coming out to .0020-.0021. Im thinking about swaping to a different bearing. These are king xp. I think I need .0025 rod bearing clearance. Its a street strip car that has a loose converter and will live between 6000-7000 rpms at WOT for 9-10 sec at a time. (hard on bearings)
Could always run a thicker oil if you're not liking the pressure you are seeing. I believe my engine is setup just a tad looser than that. I run 20-50 VR1. Also, my rings are gapped slightly wider because I had planned to spray nitrous with my build. Still made pretty great power, NA.
Anything north of 600, I like to see .0025 mains and rods, even with aluminum block builds. I’ve seen .0045 on extreme duty endurance builds. I think you’ll be ok here as it’s a street/strip build. Make sure you open up your thrust to ,007-.008. That converter will balloon and you’ll need more thrust clearance. I’ve personally gone as big as .010 on thrust for auto builds with loose converters. At your final assembly, cleanliness is absolutely a must. Wash all your parts 2-3 times. You can not get them clean enough.
Anything north of 600, I like to see .0025 mains and rods, even with aluminum block builds. I’ve seen .0045 on extreme duty endurance builds. I think you’ll be ok here as it’s a street/strip build. Make sure you open up your thrust to ,007-.008. That converter will balloon and you’ll need more thrust clearance. I’ve personally gone as big as .010 on thrust for auto builds with loose converters. At your final assembly, cleanliness is absolutely a must. Wash all your parts 2-3 times. You can not get them clean enough.
My builder puts a little bevel in the back side (I believe) thrust bearing to "help" counteract any issues with the converter, etc... Have you ever seen that done, or done it?
My builder puts a little bevel in the back side (I believe) thrust bearing to "help" counteract any issues with the converter, etc... Have you ever seen that done, or done it?
I have done the bevel. I’ve also drilled an oil feed hole horizontally through the main saddle bulkhead, directly into the oil feed for the thrust main (depends on the type of engine), to directly pressure feed the thrust…thrust bearing surface itself had a .028 hole drilled in it to get the oil to the area.
But for 99.9% of LS builds, simply opening up the oil grooves with a fine round file after setting up the thrust clearance is plenty, as long as it has enough oil pump and viscosity is correct.
That is a good suggestion, Scott, about pressure feeding the thrust. I know Kurt Urban also does that for certain apps. But you guys know where to drill. IIRC, theres a jig offered by some vendors to do what you're saying. I'd probably recommend most home garage mechanics not try it without that fixture. A .028" drill is mighty small, and easy to break off. Assuming a larger diameter is drilled in the saddle itself, maybe 3/32"-1/8"?
Anything north of 600, I like to see .0025 mains and rods, even with aluminum block builds. I’ve seen .0045 on extreme duty endurance builds. I think you’ll be ok here as it’s a street/strip build. Make sure you open up your thrust to ,007-.008. That converter will balloon and you’ll need more thrust clearance. I’ve personally gone as big as .010 on thrust for auto builds with loose converters. At your final assembly, cleanliness is absolutely a must. Wash all your parts 2-3 times. You can not get them clean enough.
Crank tapped forward with dead blow hammer and zeroed out on dial indicator. Pushed back with small screw driver looks like .007. I think thats pretty good.
Question.....I installed #1 piston and rotated the crank over expecting for the rod bolts to hit the bottom of the cylinders. It had a ton of clearance....is that normal????
also have some x bearings coming for the rods to try and get that clearance opened up closer to .0025
Question.....I installed #1 piston and rotated the crank over expecting for the rod bolts to hit the bottom of the cylinders. It had a ton of clearance....is that normal????
also have some x bearings coming for the rods to try and get that clearance opened up closer to .0025
It depends on the rod and the block. I like to use Compstars quite a bit for this reason, they always have plenty of clearance. The blocks can vary though too, so make sure to check them all. I've built a handful of 416s and haven't had to rod clearance them.
That is a good suggestion, Scott, about pressure feeding the thrust. I know Kurt Urban also does that for certain apps. But you guys know where to drill. IIRC, theres a jig offered by some vendors to do what you're saying. I'd probably recommend most home garage mechanics not try it without that fixture. A .028" drill is mighty small, and easy to break off. Assuming a larger diameter is drilled in the saddle itself, maybe 3/32"-1/8"?
Mike, the .028 is only in the bearing shell thrust surface. The saddle gets a .100 hole when I do it, but you could go a little larger I suppose. I keep it all as small as possible for strength/cracking reasons.
01-19-2024, 10:56 AM
Home built 416 
