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Old 10-07-2012, 11:56 PM   #23
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Join Date: Feb 2010
Location: NC
Posts: 174
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Originally Posted by HPF Chris View Post
Many of the builds that we've done have sleeved blocks. They are definitely much stronger than a .020" overbored block. Many of the motor failures we see have a small crack in the side of the cylinder wall. What can cause this is the head lifts, coolant flows into the cylinder and the side of the cylinder wall breaks into the water jacket. A sleeved block will handle this scenario much better and we've never seen this occur in any of the sleeved blocks we've done. However that is a condition that shouldn't happen in the first place if the tune is dialed and the head is on tight with ARP L19's. The sleeved block is a much better solution however it is mostly not necessary unless you're wanting really big numbers (over 900rwhp-1000rwhp), have already bored .020" over and need to re-bore, or just want added insurance.

Thanks for the reply Chris. Always a pleasure to read what you have to share on this forum and keep up the awesome work with your kits.

I agree 100% with everything you have written; no reason to disagree.

Although exactly what we understand by "stronger" depends a bit on the subjectivity of our criteria. Regardless, just to clarify, you haven't seen the above mentioned types of failures on unsleeved motors since you when to the L19's, correct?
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