I thought I would start sending off oil for analysis. Naturally, my sample report came back and scared me. It showed a critical level of Silicon. Can anyone help me understand what is Silicon, how important is the test and what steps I might take to investigate why.

This is a 4.3L Chevy with Brodix Aluminum heads running at about 3500 RPM constantly. It runs with Royal Purple 20W50.

Your help is appreciated.

 

F-Hi,

I'm not sure what's in Royal Purple, but if the manufacturers of the oil can't explain the silicon, you might want to know that the aluminum head castings contain silicon as a molecular binding and wear enhancement additive. If these are new heads, I can understand it for the first couple of changes.

Industrial/commercial engine? Air compressor?

 

Thanks for the information. These are relatively new heads from Brodix. The engine is a Chevy V6, 4.3L engine. The heads were put on to reduce weight as the engine runs in my experiemental airplane. I have about 130 hours on the engine, but only about 30 with the new aluminum heads.

 

F-Hi,

Just guessing on the source of the silicon, but I'm thinking it's plausible with new castings.

Incidentally, are you using a Gilmer belt for speed reduction to the prop shaft, or an enclosed drive? I know the belts are a bit lighter.

If you're looking to shave some weight, you may want to consider the LT1-style reduction gear starter.

Other possible weight trimming / distribution ideas:

Aluminum "radiator";

Remote air filter / plastic housing;

CrMo tubing for exhaust instead of soft steel;

Forged crankshaft vs. cast iron;

Aluminum coolant pump vs. cast iron;

Fluid Damper replacing OEM damper;

Alumimum battery / power cables vs. copper (or is that not allowed any longer?);


Then again, I'm guessing you already have more than a couple of bucks in your "project". Kit?

 

Once again, thanks for your input. Here are some answers:

I'm using a belted reduction unit. I like that it seems to reduce vibration and weighs less. No problems so far (see: beltedair.com)

*Got that starter (nice)
*Got that aluminum radiator (real nice)
*Really want to go remote air filter but don't know how. I need to cap off the carb and find some way of routing air to the carb but things are tight under there. Any advice on a scoop. Currently, I have a scoop I bought mounted facing with the opening aft just letting the carb pull air. I sure would like to get some ram air. I am interested if air passing over the scoop is drawn back to the carb or if it is having to pull air in.
*Exhaust is cermachromed headers.
*I am starting a project to build a new engine from scratch. The engine I run is stock with exception of the heads so I want to build a great future engine with super parts. I really want a forged crank and forged pistons but don't know where to get one for the 4.3L. I hope you do. A 4 bolt main block would be nice too?
*Already running aluminum water pump.
*Fluid damper replacing OEM damper? Is it lighter? If so, I need one.
*My battery cables are heavy (real heavy) but I don't mind it in that area.

The airplane has 130 hours on it all with the stock engine (1992) but only about 30 hours with the aluminum heads. I run at 3100-3700 RPM and average 150 - 190 MPH. Fuel is great at 3100 @ 7 GPH and 9 GPH @ 3700. I average 3500 RPM at 8.3 GPH and 170 MPH TAS.

Thanks for all your thoughts on reducing weight. I have found that you can really get light, but mainly in my wallet. Jegs and Summit keep sending the catalogs though.

 

Fluidampr makes a lightweight damper for SBC's, it will probably make your wallet about $300 lighter. I dunno if the 4.3 uses the same damper or not though.

 

Did you use silicone sealant on gaskets/bolts when you put it together? Excess sealant in the oil stream can be picked up by the oil.

In road vehicles, the typical silicon source is dirt.

I'd hope the analysis outfit knows what to expect in Royal Purple (or any other oil).

 

I did use silione on bolts, gaskets, etc and I admit, I tend to go overboard on everything. However, is silicone gasket material and silicon the same or related? When I first saw the report, I read it as silicone and then saw the word silicon. Then I realized that I do not know what silicon is.

 

Silicon is the element, which, in crystaline form, we call "sand". Melted, it's glass.

Silicone contains silicon, but my brain's too fried right now to recall how to define it.

 

F-Hi,

If you hook up with Ede (another of our moderators) he may have some good tips on building the 262, forged parts and all. His email link is at the top of the forum page. ede@thirdgen.org

The four-bolt caps are pretty easy to convert, with the possible exception of the thrust cap on the 262 (dunno for sure).

However, since you mentioned an "all out" build for the next engine, Chevrolet offers the 14011069 and the 10134371 block castings in 356/T6 aluminum. The forst part number has cast-in iron cylinder liners, and they both have four-bolt main bearing caps. The blocks weigh 70 and 75 lbs, respectively. That could save you a few pounds (if not at least from lightening your wallet).