My buddy talked to a guy at a dealorship yesterday about a small upper intake leak in his 97 Z71 with LT1. The guy said that if it goes completely that the LT1 is strong enough to handle it. The coolent would just need to get cleaned out and the engine would still be good. He then said that only 3800s seeze up because they are a weaker motor than the LT1. This confuses me when I see 150K LT1s running almost a second more in the quarter than new due to compression loss. Then you have 3800s with 200K running at or better than new times. Not to mention how well do LT1s take to boost? IDK, i'd be curious to see how an LT1 is a much stronger motor. :?

I don't see how being a "stronger motor" has anything to do with anything. Water in the oil is gonna kill any engine. Water on the bearings is bad. It has nothing to do with it.

My thoughts exactly. Bearings between engines are made from the exact same materials, and will be equally affected by the "dip".

i thought Lt1'* had a alum upper? i dont think gm put those in pick-ups

It must have been a Z28, not a Z71, unless he did an engine swap.

I'm more at home with the LT1 than the 3800, as I've owned 7 9C1 LT1 Caprices. They're both good engines, equally succeptable to grenading if they injest coolant. An LT1 has an aluminum 1-piece manifold that doesn't normally give any trouble, but they do loosen up, usually sucking in oil on the #8 cylinder and just fouling the plug. The rears leak along the rear of the manifold, where you don't use a gasket, but a bead of RTV (same as the front). The rear gives way because the EGR brings up the heat from the right-side exhaust manifold and deteriorates the RTV. It'* an easy fix, even easier than just removing the UIM on a 3800.

As far as loosing compression over the years, that'* a load of bunk. They usually slow down due to a poor state of tune, and the valve springs are prone to going weak. Actually, they were weak to begin with in the iron-head LT1s (I don't know about the aluminum head LT1s). Take a 100k+ LT1, throw on some good springs and 1.6rrs, and it will immediately wake up!

Stock LT1s don't take much boost well, due to the 10.0 to 1 compression ratio. But, like any other engine, we find ways to go fast. There are plenty of 4200lb b-bodies running 12s, 11s, and 10s, some using forced induction or nitrous, and others not (strokers).

I had a 140k mile 9C1 that ran a 14.8 at 93. All I did was a cat-back, homemade air intake, and a tune.

Yea, i'm thinkin the dealor just wants my buddy to not repair it so it goes and they can sock him for a new engine.

Nor can most engines withstand trying to compress a cylinder full of coolant (incompressible). If you're lucky, the mass coolant injestion will occur at idle and hopefully just instantly stall the engine. But that is when coolant flow is the least. I'd think it would more likely fail at some speed.

I love how these guys at dealerships think they can BS just about anybody. However, if he really believes that the LT1 won't be damaged then he'* just plain wrong. If I needed a rebuild I wouldn't go to that dealership.

97 Camaro Z28 would be an LT1, but a Silverado Z71 would be a 5.7L Vortec @ 265 HP.