jirwin
Goblin Guru
They are grade 8 M8-1.25x80mm flange bolts if anyone's curious.
jirwin
Goblin Guru
Update on the main bolts... here is some video showing what's going on.
@Desert Sasqwatch I will be contacting OTTP to see what they think of the whole ordeal. One of the bolts has a cracked head too. I had heard bad things about OTTP, but I guess this is what I get for cheaping out and not getting the ARPs.
@Desert Sasqwatch I will be contacting OTTP to see what they think of the whole ordeal. One of the bolts has a cracked head too. I had heard bad things about OTTP, but I guess this is what I get for cheaping out and not getting the ARPs.
Desert Sasqwatch
Goblin Guru
Some of us have had some 'trying' experiences with OTTP from poor quality parts, to parts not being the same as described, to their refusal to accept returns - and then charging an exorbitant restocking fee if they do accept it back. Pretty much the polar opposite of DF in terms of service and honest business. But this is just my highly biased opinion - sorry to ramble on. 
jirwin
Goblin Guru
Gotta learn the hard way I guess. I'm going to see if they'll replace the two I'm having trouble with, or if they'll just take them all back. ZZP doesn't sell the ARP main studs, and I can't find the stock ones on Rock Auto. OTTP does sell the ARP's but how they handle this situation will determine what I do regarding that. I really just wanted reusable ones so I can measure bearing clearances without having to use a new set of TTY bolts the second time.
SmsDetroit
Goblin Guru
Well I just installed one of their clutch kits and I think the slave is leaking
Desert Sasqwatch
Goblin Guru
Maybe use the original bolts for the bearing clearance check? Torque to spec ft.lb. value, then torque 1/2 of the additional degrees of turn - since the yield has stretched the bolts already getting to the ft.lb. value will take up most of the existing stretch. Just trying to think of how to do this without buying 2 sets of brand new bolts - since I will eventually be doing the same thing.
Looks like the main bolts are GM# 11571239 and the Girdle bolts are GM# 11588733. Both seem a little spendy, but I didn't check ARP prices.
Both are available at RockAuto and other places. One odd thing - RockAuto says the girdle bolt length is 80mm, but another website says its 90mm. Weird.
jirwin
Goblin Guru
The center 20 main bolts are M10-1.5x145mm. The outer 10 are M8-1.25x80mm
jirwin
Goblin Guru
Couple updates. Talked to OTTP and it sounds like they're going to take care of my main bolt issue. Gotta call again tomorrow.
In the mean time I started installing ZZP 82# valve springs. Tedious AF, but will be well worth it. I think with that, my already deleted balance shafts, and an ATI super damper I should be able to safely do 8K RPM.
Also on the to do list is to measure combustion chamber volume so I can effectively measure compression ration. Have a couple liquid syringes in the mail so I can use water to do so. Hopefully all said and done I'll be around 9.25:1.
In the mean time I started installing ZZP 82# valve springs. Tedious AF, but will be well worth it. I think with that, my already deleted balance shafts, and an ATI super damper I should be able to safely do 8K RPM.
Also on the to do list is to measure combustion chamber volume so I can effectively measure compression ration. Have a couple liquid syringes in the mail so I can use water to do so. Hopefully all said and done I'll be around 9.25:1.
comegetjoe
Goblin Guru
Hell yeah!!!
jirwin
Goblin Guru
OTTP's going to ship me 3 replacement bolts (2 bent, one head cracked). Hopefully they get to me by the weekend so I can start getting this thing assembled!
In the mean time, I snagged an LS4 TB for $25 bucks. I had to do a shitty port of my M62 inlet to get the butterfly to fit in the inlet. I 3D printed a little adapter doo-dad thats the size of the LS4 TB so I could stencil out the area I needed to grind off. It looks like **** but its fairly smooth. Good enough for me anyway, and the butterfly fits! Glad I didn't try to port my head myself. Not easy! I don't think I'll be trying the "Christmas Tree Port" myself.
Stencil:
LS4 vs LSJ TB
Shitty port:
In the mean time, I snagged an LS4 TB for $25 bucks. I had to do a shitty port of my M62 inlet to get the butterfly to fit in the inlet. I 3D printed a little adapter doo-dad thats the size of the LS4 TB so I could stencil out the area I needed to grind off. It looks like **** but its fairly smooth. Good enough for me anyway, and the butterfly fits! Glad I didn't try to port my head myself. Not easy! I don't think I'll be trying the "Christmas Tree Port" myself.
Stencil:
LS4 vs LSJ TB
Shitty port:
jirwin
Goblin Guru
@snirtman I don't think the 10 girdle bolts GM# 11588733 is right. The RockAuto description says 0.9" of thread. Here is a picture with one of the actual bolts (right) and with one that I tried to replace it with that's grade 10 (left). The grade 10 doesn't have enough thread. The one you listed also looks like it would be around the same size. Where did you find the part number?
Attachments
A couple of OEM parts websites call out the part number, but neither calls out the length:
1. GM Parts Direct shows only a generic image of a bolt
2. GM Parts Giant shows an actual bolt
A listing on Amazon says its a M8 x 1.25 x 80.8., same as Rock Auto, and both picture a bolt that appears to be the same as the GM Parts Giant bolt.
However a listing on Crate Engine Depot says its M8 x 1.25 x 90.5, with 21.6mm of thread, so not sure what to make of that.
Hope that helps?
Ross
Goblin Guru
You are asking if you can replace the Engine Crankshaft Main Bearing Cap Bolts with grade 8 all thread bolts?
The Engine Crankshaft Main Bearing Cap Bolts is not one area I would cut corners.
Can you even find all thread bolts in grade 8? Grade 8 is standard, and your engine is metric.
There are several grades of bolts but the three common grades for SAE are 2, 5 and 8.
The common class (grades) for metric are 5.8, 8.8, 10.9 and 12.9.
The Engine Crankshaft Main Bearing Cap Bolts is not one area I would cut corners.
Can you even find all thread bolts in grade 8? Grade 8 is standard, and your engine is metric.
There are several grades of bolts but the three common grades for SAE are 2, 5 and 8.
The common class (grades) for metric are 5.8, 8.8, 10.9 and 12.9.
Which bolts are we talking about at this point? If they are true TTY on something that needs a particular clamping load, the only way to obtain that particular load is to use bolts of the correct material and have the correct diameter over a particular length. These can be different from one companies design to the next, but hopefully they are actually designing them, and just not selling bolts that “fit”.
Typically, a true TTY bolt will have a reduced section above the threads to control the stretch of the bolts. If the proper stretch isn’t obtained, the bolts will fatigue and fall.
Typically, a true TTY bolt will have a reduced section above the threads to control the stretch of the bolts. If the proper stretch isn’t obtained, the bolts will fatigue and fall.
jirwin
Goblin Guru
Sorry, just the 10 outer main girdle bolts. Not the 20 "main cap" bolts. The ones numbered in the attached picture. @Ross I didn't know there was a difference, but yes Grade 8.8 is what I sourced. I don't think these outer ones are as important as the inners. The outer ones I was having trouble sourcing as you can read. The partial thread 8.8s I sourced don't have enough thread. The full threads today do (though they are not flanged, but I have a washer). The GM part number that @snirtman provided I'm skeptical of based off of RockAutos description, which is the only reason I'm even considering going this route.
@Gtstorey yeah, being full thread and not having any "reduced section" is what worries me. I just looked up the torque spec again and its only 18ft lbs, no extra degrees after. Probably not a concern?
@Gtstorey yeah, being full thread and not having any "reduced section" is what worries me. I just looked up the torque spec again and its only 18ft lbs, no extra degrees after. Probably not a concern?
