LLY engine build on a budget

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stlled

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Jan 30, 2014
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Sorry if this is off post, Im guessing I should be around 500 hp, COTN tune with garret 4094, 4" with a 3"DP and a fass 150, s&b intake a TMP on a lly. Anyone care to take a guess of just throw her on the DYNO? sorry for highjacking .....
 
hondarider552

hondarider552

Getting faster
May 28, 2008
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My engine is a good 30 psi low on compression on a few holes. Suspecting rings or few melted pistons. Doesn't surprise me from the amount of spray it's seen. Idles a bit rough. One more local race April 18th and she's comin out.
 
Burn Down

Burn Down

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Sep 14, 2008
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Boise Idaho
stlled said:
Sorry if this is off post, Im guessing I should be around 500 hp, COTN tune with garret 4094, 4" with a 3"DP and a fass 150, s&b intake a TMP on a lly. Anyone care to take a guess of just throw her on the DYNO? sorry for highjacking .....
Click to expand...

No way to know without seeing your pulse width and then its still a guess but better educated...:D
 
cstephens93

cstephens93

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So once again, I may be causing more headaches, but when the time comes, I should buy new pistons to build my engine or I should just have my stock ones machined....All of this if I'm trying to make 700hp at most, safely. I saw in a post once that McRat said

McRat said:
The 3 weak points of a Dmax in my opinion are the rods, pistons, and cam key.

Once you settle those three issues you will be fine.

And after that point, the gain in reliability per dollar goes nuts, as does internal engine power-enchancing mods.
Click to expand...
 
CaptPhil

CaptPhil

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Sep 10, 2011
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I would just have your stock ones de lipped if you are only going for 700hp. Now if you think you might get the itch to go bigger then I would consider going aftermarket.
 
cstephens93

cstephens93

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CaptPhil said:
I would just have your stock ones de lipped if you are only going for 700hp. Now if you think you might get the itch to go bigger then I would consider going aftermarket.
Click to expand...

What do delipping stock pistons even do? Never been able to find a good explanation. All I ever see are people mentioning delipped LB7 pistons
 
Burn Down

Burn Down

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Sep 14, 2008
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cstephens93 said:
What do delipping stock pistons even do? Never been able to find a good explanation. All I ever see are people mentioning delipped LB7 pistons
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De-lipping does two things, one it removes the sharper edge from the piston bowl to reduce the potential of melting, two it lowers compression ratio... Fingers modeling of stock, de-lipped, & oval bowls showed that de-lipped were no stronger than stock and maybe slightly weaker from a cracking stand point.
 
cstephens93

cstephens93

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Burn Down said:
De-lipping does two things, one it removes the sharper edge from the piston bowl to reduce the potential of melting, two it lowers compression ratio... Fingers modeling of stock, de-lipped, & oval bowls showed that de-lipped were no stronger than stock and maybe slightly weaker from a cracking stand point.
Click to expand...

So if it is no stronger than what is the point
 
cstephens93

cstephens93

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Burn Down said:
De-lipping does two things, one it removes the sharper edge from the piston bowl to reduce the potential of melting, two it lowers compression ratio... Fingers modeling of stock, de-lipped, & oval bowls showed that de-lipped were no stronger than stock and maybe slightly weaker from a cracking stand point.
Click to expand...

I see that it lowers compression and reduces melting potential, but is this also making them weaker from a cracking standpoint?
 
Burn Down

Burn Down

Hotrodder
Sep 14, 2008
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Boise Idaho
cstephens93 said:
I see that it lowers compression and reduces melting potential, but is this also making them weaker from a cracking standpoint?
Click to expand...

IIRC, according to Fingers piston modeling program he thought they were weaker than stock, from a cracking stand point. You need to remember though that the LB7/LLY piston isn't known for breaking easily de-lipped and shaved...
 
cstephens93

cstephens93

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Burn Down said:
IIRC, according to Fingers piston modeling program he thought they were weaker than stock, from a cracking stand point. You need to remember though that the LB7/LLY piston isn't known for breaking easily de-lipped and shaved...
Click to expand...

Hmm I see. Thats interesting. I have so much more to learn in regards to building a motor
 
cstephens93

cstephens93

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So in the future, when i plan on building my motor. I cant decide If I should just try to find a motor with some less miles and build that motor, or If I should just use my motor at who knows how many miles by the time I build it and install rods, pistons and such.

Will I need to bore my cylinders? Or even put new heads on it? I just recently did my headgaskets back in Feb with new grade Cs and ARP studs
 
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