Reworking LS6 shortblock...I have questions.
04-03-2011, 07:17 AM
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Reworking LS6 shortblock...I have questions. I recently acquired an LS6 shortblock out of an '02 Z06. Motor has 15k miles on and seems to be in perfect shape. It will be going into my '98 Z28 this fall. I originally planned on ONLY replacing the rod bolts with Katech's, but I recently changed my mind. I have a mid 230's cam currently, and would like to go bigger with this motor.
Therefore, instead of cutting valve reliefs myself, and the pistons being the next weak link (I believe) after the rod bolts, I looked into getting a set of forged pistons. This is where I need help. I really do not want to disassemble the shortblock and spend the extra money to have to taken to 3.905" as most aftermarket pistons require. I found these:
http://www.texas-speed.com/shop/item...d=119&catid=38
Would I simply be able to swap these out with the old pistons and be on my way? Or would the engine still need taken apart and balanced? I do have a budget, and I'm trying to save every dollar I can so I can afford TFS 215's
Do those pistons have valve reliefs? It says -4cc dish, but can someone explain that? Or point me in another direction? I know if I go to 3.905 I have a ton more choices, but I'm just worried about the machining bill...and if I would need new bearings if it were to be honed...etc.
Again, I do apologize for the long read but I hope SOMEONE can help me out.
Allen
Therefore, instead of cutting valve reliefs myself, and the pistons being the next weak link (I believe) after the rod bolts, I looked into getting a set of forged pistons. This is where I need help. I really do not want to disassemble the shortblock and spend the extra money to have to taken to 3.905" as most aftermarket pistons require. I found these:
http://www.texas-speed.com/shop/item...d=119&catid=38
Would I simply be able to swap these out with the old pistons and be on my way? Or would the engine still need taken apart and balanced? I do have a budget, and I'm trying to save every dollar I can so I can afford TFS 215's
Do those pistons have valve reliefs? It says -4cc dish, but can someone explain that? Or point me in another direction? I know if I go to 3.905 I have a ton more choices, but I'm just worried about the machining bill...and if I would need new bearings if it were to be honed...etc.
Again, I do apologize for the long read but I hope SOMEONE can help me out.
Allen
04-03-2011, 07:30 AM
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The stock LS6 shortblock will make more power as is. Bigger is not always better, overall planning and matching of parts to complement each other is the way to do it.
Just changing rod bolts is sufficient, one at a time, without removing caps. Katech bolts are same as stock but in higher tensile strength, so they do not require any work on the rods.
With that mod you'll be able to spin to 7K rpm with no issues and have a cam as big as T-Rex.
With the 215s, I would go with a Vengeance cam. Proven combo, over and over.
Just changing rod bolts is sufficient, one at a time, without removing caps. Katech bolts are same as stock but in higher tensile strength, so they do not require any work on the rods.
With that mod you'll be able to spin to 7K rpm with no issues and have a cam as big as T-Rex.
With the 215s, I would go with a Vengeance cam. Proven combo, over and over.
04-03-2011, 07:52 AM
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Ok Predator, I appreciate your input very much. My current 243's are 62cc's and I was going to run these with Cometic .40's OR wait until I can afford the TF's. If I stay 243's for a while, should I rent a Lindy and just cut what is necessary for the cam I choose?
04-03-2011, 11:43 AM
#5
I'm pretty sure you'ld need to rebalance w/that piston. Factory slugs are like
434grams. I didnt see a weight on that Mahle. Also the block would need
honing unless you planned on swapping the rings over and keeping them in
the same cylinder. If you were going big on the cam ^240 and say .600 lift
then just notch the stock ones. Also FWIW Trick Flows 13deg valve angle
and Mast 11deg heads offer the ability to fit a larger cam without notching
because of the rolled over geometry.
434grams. I didnt see a weight on that Mahle. Also the block would need
honing unless you planned on swapping the rings over and keeping them in
the same cylinder. If you were going big on the cam ^240 and say .600 lift
then just notch the stock ones. Also FWIW Trick Flows 13deg valve angle
and Mast 11deg heads offer the ability to fit a larger cam without notching
because of the rolled over geometry.
