| Re: Top end swap on my 92 LT1 to the LT4 (fresh start) |
Subject: Re: Top end swap on my 92 LT1 to the LT4 (fresh start) by biggrizzly on 2011/8/10 12:42:27 Any plans to freshen the bottom end? I'm not being a Debbie Downer... just relaying some good honest first hand experience. I once scoffed at people that told me this very thing and thought that I would beat the odds; but I didn't Only reason I ask you about your bottom end plans, is that in 2007 I did a top end rebuild on my motor. At that time it had about 150k miles on it. It was well taken care of up to that point with regular oil changes and service. It was not burning oil or other issues; matter of fact when the heads came off the cylinder bores looked great, as did the cam and lifters. The engine also was clean as a whistle on the inside with just a bit of carbon build up on the valves. I had a bad water pump, some oil leaks and an Opti-Spark with 150k miles on it. I only had enough money to do a H&C swap and a small one car garage that really gave me no room to extract the motor. So, I decided to just do H&C. I probably spent nearly enough doing the top end only to do the whole damn thing if I had planned better too. Once completed it held together fine and gave me more power and grins for about 18 months or so. I was a happy camper. However, at my first trip to the drag strip ever with this car, I toasted every bearing on the crank assembly on my second run of the day. This was just over a year ago. When the engine was disassembled my builder said that it appeared that this damage was taking place over time and that the run at the track was just the straw that broke the camels back. Matter of fact I didn't even throw a rod, just spun a few bearings and heated things up real good!! Good enough to initially freeze up the bottom end. After it cooled, it would crank and try to run but you could hear the bearings just grinding away. I wish I had a video tape of that sound... it would convince a lot of folks to check that bottom end real good before just doing the top. With all this said, I know that there are good reasons to just do top end rebuilds and your plans sound good and solid. I just wanted to relay my experiences as they are not told third person or about a friend of a friend. It happened to me. |
