How big will the holes for the thermocouples need to be, and will they 4 holes compromise the strength of the manifold?

I don't know in general but mine are about 1/4". I have about 30k on my cast mani and it's fine so far.

His mani comes with a lifetime warrantee from cracks. Or at least until I disappear from the internet or sell my welder.

EDIT: my ktype EGT probe uses a 1/8NPT adapter. It shouldn't adversely affect it...hmmmm.

I would think you could wire a safety thing like that into, say, a knock signal. So, you'll get a light, and it'll pull timing (on low oil pressure)...

I have the 4 channel aircraft EGT unit mentioned in this thread mounted in the left center vent position. The price is really very reasonable for what you get and the digital output with color-coded bar graph blows the Westach away.

M.

M: A few questions---

What manifold do you have?

Got a coolant reroute?

Duel feed fuel rail?

Turbod and if so, what injectors?


And lastly-- the biggie: What temperature variance have you seen between your cylinders? What's the max you've ever seen?

All the previous questions make the answer to the last question useful :)

thanks

Incredible how I missed this thread, since I have quad EGTs and quad LC-1s. My advice, don't try unless you know you need them. Costly, and for most builds, unnecessary.

Jim

Looking at your signature... wow. If you could make a build thread... that would be awesome. Pics/details/how/why/whatfor/uses/data... anything would rock.

Built 99 engine, 0.5 over.

Manifold: The semi-new cast manfold. gihttp://www.bellengineering.net/product_info.php?products_id=36

Coolant re-route: Yes.

Duel fuel-rail: I never duel with a fuel rail - they spray fuel in my eyes and I always lose. But I do have a dual-feed rail that I never duel with. <grin>

T28 turbo, oversize valves headwork, 550 injectors.

#2 and #3 consistently about 100 F (about 50C) higher than #1 and #4. I don't have a cam sensor so I no sequential injection, i.e.. can't tune it out with fuel.

You wee asking such specific questions -- do you have specific experience with this?

A picture depicting:

- a drop of blood
- a bowl of tears
- a shirt full of summer sweat
- and some fresh bile

will have to do for now.

Jim

Any turboe?

Any trouble getting the LC-1s to work right at the exhaust ports? I thought that was supposed to be impossible even NA.

M.

The copper heat sinks did the trick nicely. I *was* expecting trouble, but everything went ok.

Jim

Yes, in my previous car but not on this one, sorry.

Jim

Multi cylinder EGT/CHT engine analyzers are fairly common in high performance piston aircraft BUT they are anything but cheap. A multi channel (6 EGT/6 CHT/2 TIT/RPM/MAP) JPI EDM 800 analyzer lists for about $3,700. Single cylinder/multi cylinder aircraft EGT gauges are relatively cheap (a cheap Westech single cylinder EGT can be found for under $100) but the multi-cylinder analog gauges are very hard to monitor/interpret in a busy cockpit (aircraft or "race car").

It is important to note that many of the older EGT probes (aircraft and automotive) are slow reacting to EGT changes. JPI was one of the first to use modern fast reacting EGT probes. I've flown EGT equipped aircraft with both the old Westech style probes and the new JPI style fast reacting probes and there is NO comparison.

I think one may be able to find a fairly robust EGT analyzer (e.g., fast reacting probes with data logging) by looking at the niche manufacturers for the experimental aircraft market. This equipment does not need to meet FAA specs/require FAA certification. Accordingly, "experimental" engine instrumentation/analyzers are cheaper and often have more features than the certified versions.