Chevy LT1 Head Questions - Performance Q&A

Kevin McClelland Jun 1, 2009 0 Comment(s)
0906chp_02_z Chevy_lt1_engine_performance_questions Chevy_small_block_engine 1/2

Neglected Tools
If you're like most of us, servicing your vehicle isn't way up there on the to-do list. It's more fun installing a set of headers, swapping out the latest intake manifold, or if you like to keep your hands clean-and need instant gratification-blowing in a new program into your PCM. There's one tool many of us have that I know gets neglected. How about the wheel bearings and brakes on your trailer? Many of us have trailers, and some have more than one. What if you lost a wheel bearing going down the road with your prized possession on its back? This is what happened to a good friend of mine on his way to Las Vegas with his triple-axle, gooseneck Pace trailer! As he came to a stop, the axle in question was up in flames! His trailer even had the self-lubricating bearings that were submerged in a bath of gear oil! The point I'm trying to make here is that we all do it. We come home from the races or whatever activity and unload our cars, then stash the trailer until next time.

With my family's move to Southern California coming up this month, I decided to service the bearings on both my trailers before we struck off. I couldn't afford to be stuck on the side of the road trying to find bearings or, worse yet, needing a new axle. I've had one of the trailers, a 24-foot Pace Shadow, for 10 years and 40,000 miles. I've been very nice to the electric brakes, using up the tow vehicle's brakes more than the trailer's. I've heard horror stories about electric trailer brakes and the expense of replacing them.

Popping off the wheels and drum, I came to find that the bearings were just fine. The axles and brakes are made by Dexter and have a nice feature that allows you to inject grease into the axle, which packs the hub assembly full of grease. My problem wasn't neglecting the bearings; it was the brakes. At first glance, everything looked great. The lining was about half worn, but there was cracking in the lining throughout the shoe.

Next I found that because I had not kept up on the brake adjustment, the electromagnet that rides on the brake drum when engaged had overshot its mating surface. This had worn the magnet excessively but luckily had not damaged the drum. So I'm off to the brake store for shoes and electromagnets! Again, if I would have stayed up on the adjustment I wouldn't have been looking at this expense! Think of this the next time you dump your car off the trailer and park it for next time.

As for the move down south, I have found a place to hang my shingle. K&N Engineering has taken me in as Special Project Manager. I'll be looking for new opportunities for K&N to apply its filter technologies. Also, I'll be digging around for groundbreaking uses within our industry. It really feels good to finally move from the dirty end of the car up to the clean end! Stay tuned for new adventures.

Round? Who Needs Round?
Q: I got an engine block from a friend who didn't want it because it had water damage to the cylinders. Well, after a few hours of sanding and a honing tool, this block ended up looking great! The casting number is 10125327, confirming it's an LT1. Can I put any heads on this engine, or do they have to be LT1 heads?
Freddy Reyes
Santa Ana, CA

A: Taking sandpaper to cylinder walls can be very dangerous. If you used very fine (1,000-grit) sandpaper to clean a little surface rust off the cylinders, I wouldn't worry. However, sanding for a few hours and then using a honing tool is what worries me. Was the honing tool a bottle-brush glaze breaker or a true shoe type-stone hone? If you take 400-grit sandpaper to a cylinder wall and track the damage with a micrometer, it will surprise you how much material you can remove easily. This creates an out-of-round condition that the rings will never have a chance to seal.

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