Rebuild it or swap it out?

V12-Engine
21

Driving up The Sunshine Skyway Bridge or other long steep bridge would limit excess speed of an ITU.

22

Every time I hear of someone ready to make a huge decision based on compression readings, I wonder how they are checking their compression. I thought I had lousy compression until I realized my compression gauge was not being used properly (by me!). It is the 2-piece type that has a short adapter hose with spark plug threads and o-ring on one end and a standard air supply fitting on the other end. The gauge head has a hose with a mating coupler for the adapter hose. You hand-tighten the adapter hose in as far as it’ll go, and then couple the gauge hose to it then take your reading. That’s the easy way!

Now, the kit came with an optional screw-in spark plug adapter that has no hose. It is about the size of the spark plug and can be wrench-tightened into the plug hole. Since it is much shorter than the hose adapter, it’s not as easy to use, especially on the V12. However, I found that on my engine, this short adapter-not the easy hose adapter -must be used for accurate readings! Before, I had been screwing the hose adapter in as tight as it would go but that is limited by the torsional stiffness of the hose and apparently it was not fully seating sometimes. I was getting 100-120 psi (warm engine) using the hose adapter. Now, with the short adapter I could wrench-tighten, I got 115-120psi. The latter readings are very satisfying since past compression tests were lower and variable which added to my perceptions of this V12 being a very enigmatic engine. Well, anyway, one mystery solved!

Cheers,
Tony H

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23

No, it wouldn’t. You still need to get to redline. It might take longer, and you might not have to repeat it so many times, but you’d still need to attain the same speed.

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24

I had never heard of an ITU. Funny how normal driving can be discribed :rofl: At least that might explain why I never had any trouble with stuck piston rings :thinking:

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25

I used to use ITUs a lot, back in the day: I had customers who regularly "gramma-ed’ their car: I take them for a hard blast, up I70 to Evergreen, and voila!

Nice-running engine, again!