Rebuilding stock bottom end question.
3.898. Is the 3.905 to accomodate a cleanup hone for a rebuild?
Also looking at some piston specs gotten from Thunders website
Diamond Pistons LS1 Forged Flat Top Piston set w/ -2cc Valve Reliefs, 3.905" BORE / 3.622" Stroke / 6.098" Rods / 1.340" Comp Height / .945 x 2.500 Wrist Pins Included
Can somebody run down the list of what each spec means? the first two I get cause they seem to be referring to the stock bore(with cleanup hone?) and stroke.
But this I am not sure of
/ 6.098" Rods / 1.340" Comp Height / .945 x 2.500 Wrist Pins
Any explanations would be nice as I may try to rebuild the motor myself if it turns out that a ring is bad and as you can probably tell this will be my first motor rebuild. Just trying to learn here.
3.663" is the stock stroke
6.098" is the stock LS1 rod length. When replaced with an aftermarket forged rod, a 6.100" SBC rod is usually used (much cheaper than having custom rods made) as the large end of the rods (both LS1 and SBC) use a 2.1" bearing (both the same).
1.340" compression height is the distance from the center of the pin to the top of the piston. The thicker the CH, the stronger the piston will be. The CH is reduced (pin is moved higher in the piston) as stroke and/or rod length increase to keep the top of the piston at the same distance from the crank (deck height).
-2cc is a how much "space" the valve reliefs in the pistons will add to the overall cc (how it will effect compression).
.945" wrist pin is the size of the stock LS1's rod wrist pin (if you are reusing the stock rods). If you go with a forged SBC rod, you will use a .927" wrist pin.
In order the swap rings, you (and I) will HAVE to rehone the cylinder (the motor will have to come out of the car) to make the new rings seal. With that in mind, you might as well have the motor bored 0.010" (usually ~$600 for a FULL block work over.....line bore, deck, cylinder bore, and hone) and install forged pistons.
I don't know what to tell you on rods.....some people say the stock rods will do wonders (someone said they got 550+ rwhp through ARP bolted stock rods at 7300RPM) while others say they won't go much past 450 rwhp so......
I personally am going to go with Eagle forged 6.125" rods as they are $400 from Summit/Jegs/etc. and are good for 700 crank hp (must more than I will EVER do).
BTW - I spoke to Paul @ Thunder and Chris @ Diamond about what I wanted from the car and took their suggestions on which set up to go with. Great people to deal with.
6.098" is the stock LS1 rod length. When replaced with an aftermarket forged rod, a 6.100" SBC rod is usually used (much cheaper than having custom rods made) as the large end of the rods (both LS1 and SBC) use a 2.1" bearing (both the same).
The new Eagle cranks hitting the market also call for 6.100" rods.
I'm a little confused here..
The new Eagle cranks hitting the market also call for 6.100" rods.
I'm a little confused here..
A 6.125" rod is used with stroker cranks in order to keep a good rod length to stroke ratio (thus the Lunati rods that are used in their 382 stroker kit are 6.125"). At the same time, adding a longer rod to a stock stroke crank will only make the ratio that much better. The only think to watch out for (going longer) is that you don’t make the rod too long so that the compression height gets so small that:
a) the pin gets into the oil control ring (you burn more oil)
b) the compression height gets so short that lots of nitrous or FI (cylinder pressures) could crack the top ring land
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Also has anybody heard more about those eagle rods. Thats a good price.
And help a brother out. What is an SBC rod?
yep.....I will use a 6.125" rod in whatever I do

a lot of people seem to be using the Eagle rods without any problems. There is a limit to what they will take (Eagle says 700 HP max and I would not run past 7500RPM) but considering the next step up is $800 for Lunati Pro rods.......I think they will do for what I want (especially since there are people pushing ARP bolted stock LS1 rods to 575+ RWHP
).SBC = Small Block Chevy.....DOHHHHH
Also has anybody heard more about those eagle rods. Thats a good price.
And help a brother out. What is an SBC rod?
IMO if your going to spray - it probably depends on how much you want to spray. If you going to do big shots go forged. I'd have to go forged if I sprayed at all so I wouldn't worry about it.
SBC = Small Block Chevy.....DOHHHHH

Damn is all I can say about that.
Do you guys think that the JE pistons are the Diamond pistons are better?
Like T/A said, coating is a good deal. It keeps the heat in the combustion chamber and does not let it saturate the pistons (more power and longer parts life). I plan to having the piston tops and the CC chambers on my heads done when I rebuild (here is one place http://www.swaintech.com/price.html ) as it’s not that expensive and every little bit helps.









