Main cap dowel holes straight through caps?
01-01-2019, 05:38 AM
#1
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Main cap dowel holes straight through caps? Yo, read through the stickies, did searches, couldn't find the specific answer I'm looking for.
Question is, can dowel holes be drilled straight through the main cap between the bolts without compromising strength?
Reason I ask is because I have a ratty old 5.7 Ls1 gen 3 engine lying around. I want to do a mega sloppy back yard build with it, if the main caps can be drilled straight through with them still bolted down I'll just do that.. but if people have already tried and know it just weakens them, I won't bother and maybe just get some studs and hope they hold the crank in line well enough.
I plan to keep the stock block & crank but concrete fill it, throw some pistons/rods in it, cam/valvetrain, diy port/polish the stock heads, maybe some fasteners and cram boost through it with e85, meth, whatever. I know it won't be the most indestructible engine because the cylinder walls of those blocks are fairly weak apparently, but w/e may as well send it.
Question is, can dowel holes be drilled straight through the main cap between the bolts without compromising strength?
Reason I ask is because I have a ratty old 5.7 Ls1 gen 3 engine lying around. I want to do a mega sloppy back yard build with it, if the main caps can be drilled straight through with them still bolted down I'll just do that.. but if people have already tried and know it just weakens them, I won't bother and maybe just get some studs and hope they hold the crank in line well enough.
I plan to keep the stock block & crank but concrete fill it, throw some pistons/rods in it, cam/valvetrain, diy port/polish the stock heads, maybe some fasteners and cram boost through it with e85, meth, whatever. I know it won't be the most indestructible engine because the cylinder walls of those blocks are fairly weak apparently, but w/e may as well send it.
01-01-2019, 10:20 AM
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FormerVendor
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Billet Main Caps with register Hi Z, the LS-1 Powdered Metal Main Caps crack @ 1000+HP.
MY METHOD is to fit billet caps AND register those STEEL caps to the Crankcase as is done between a connecting rod/rod cap. (tube bushing)
When this method is used, you will find the operation easy.
Lance
MY METHOD is to fit billet caps AND register those STEEL caps to the Crankcase as is done between a connecting rod/rod cap. (tube bushing)
When this method is used, you will find the operation easy.
Lance
Last edited by pantera_efi; 01-01-2019 at 11:42 AM.
01-01-2019, 11:14 AM
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thanks for the response! But I don’t quite follow, so like a main girdle type thing made of billet? Or Billet steel main caps installed while the conrods are out?? I’m not sure if your wording is throwing me off or if I’m just an idiot haha
01-01-2019, 11:42 AM
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Steel Main Caps Hi Z, OK. YES, upgrade the Main Caps to a Steel Cap and use studs. (Align Hone Required)
The area in the crankcase where the center stud is placed can be "overbored" (tubind OD)
Then bore the Stud Hole to a depth of 3/8" with the same work done to the Mail Cap.
A "thin wall" bushing/sleeve (S/S tubing) of a length of .700" is then seated into the block.
The stud should fit inside the Sleeve without contact.
Lance
The area in the crankcase where the center stud is placed can be "overbored" (tubind OD)
Then bore the Stud Hole to a depth of 3/8" with the same work done to the Mail Cap.
A "thin wall" bushing/sleeve (S/S tubing) of a length of .700" is then seated into the block.
The stud should fit inside the Sleeve without contact.
Lance
01-01-2019, 05:23 PM
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ModSquad
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We drilled mine straight through the caps between the bolt holes, for my steel pins, but I used billet caps from Katech. I wasn’t keen on the idea at first, but I saw that Kurt Urban was doing it a lot, and he said he was far more worried about the 4 bigger holes for the studs cracking, than the 2 smaller holes he just drilled. Use red loctite to hold the pins into the block. I should have pics in my build thread, in my sig.
01-01-2019, 07:36 PM
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We drilled mine straight through the caps between the bolt holes, for my steel pins, but I used billet caps from Katech. I wasn’t keen on the idea at first, but I saw that Kurt Urban was doing it a lot, and he said he was far more worried about the 4 bigger holes for the studs cracking, than the 2 smaller holes he just drilled. Use red loctite to hold the pins into the block. I should have pics in my build thread, in my sig.