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Dec. 2, 2010 6:36 p.m. MrBenjamonkey HalfDork

I've finally found a good motor to swap into the Nubira. It's a 1.8L DOHC Opel/Aveo/Daewoo style E-tech. This is not the same engine as the Ecotech, and as far as I know they share no parts. I want to take the entire thing apart for educational purposes, so the rods, mains, pistons, head, etc are coming out. I'm just going to buy a Daewoo rebuild kit, so new bearings/gaskets/waterpump/timing belt type stuff.

The ideas I have so far:

Using scales stolen from the science department and a dremel tool to polish and balance the rods.

De-burring the block, again, just a dremel tool.

Porting the intake and exhaust manifolds. Port matching everything. Depending on which intake manifold I get (aluminum or plastic), I might try cutting down the runners and shortening it.

Building a baffling system for the oil tank to prevent starvation. I was thinking I'd just use scrap metal and a welder for this. I was also considering opening up the drainage holes in the cylinder head since the 1.5L version of this engine pushes too much oil up there in racing conditions.

Polish the combustion chambers, unshroud the valves.

Maybe some mild cams. Maybe.

Is there anything else I could do cost effectively? Anything I should look out for? Anything patently stupid in what I'm planning?
Dec. 2, 2010 6:51 p.m. Tom Suddard SonDork

I don't see anything wrong, it looks good. How accurate are the balances you have access to?
Dec. 2, 2010 6:53 p.m. Nashco SuperDork

Don't bother with a baffle, you'll only be teaching them how to waste time on things that are unnecessary for the application (IMO).

I think the most important things they could learn about rebuilding an engine are:

1 - Catalog everything well while they take it apart (pictures, ziploc bags, notes!).
2 - Clean everything extremely well before rebuilding (machine shops can hot tank parts for very little money and they look like new).
3 - Make sure you have all the parts you need before you start taking things apart. Stalled projects waiting for parts are the hardest ones to finish!
4 - Have a service manual and a torque wrench and use them constantly!

Note that these are all very cost effective and will teach good habits for life in general, not just working on cars. Documentation, thoroughness, research, following instructions for critical work, etc.

Other good practice notes: Use assembly lube for all bearing surfaces (except new cams, which require special break in procedures) and make sure you get good oil pressure cranking it over before you hook up the fuel and ignition.

Bryce
Dec. 2, 2010 7:06 p.m. MrBenjamonkey HalfDork

Tom Suddard wrote:

I don't see anything wrong, it looks good. How accurate are the balances you have access to?

I don't have a balance. I have scales.

I was planning to hang one end of the rod from a fixed height relative to the scale and weigh the other end. I would then swap ends, record both weights and make them all match.

Like this:
Dec. 2, 2010 7:09 p.m. MrBenjamonkey HalfDork

Nashco wrote:

Don't bother with a baffle, you'll only be teaching them how to waste time on things that are unnecessary for the application (IMO).

I think the most important things they could learn about rebuilding an engine are:

1 - Catalog everything well while they take it apart (pictures, ziploc bags, notes!).
2 - Clean everything extremely well before rebuilding (machine shops can hot tank parts for very little money and they look like new).
3 - Make sure you have all the parts you need before you start taking things apart. Stalled projects waiting for parts are the hardest ones to finish!
4 - Have a service manual and a torque wrench and use them constantly!

Note that these are all very cost effective and will teach good habits for life in general, not just working on cars. Documentation, thoroughness, research, following instructions for critical work, etc.

Other good practice notes: Use assembly lube for all bearing surfaces (except new cams, which require special break in procedures) and make sure you get good oil pressure cranking it over before you hook up the fuel and ignition.

Bryce

Out of curiosity, why are you anti-baffle?
Dec. 2, 2010 7:50 p.m. chknhwk Reader

I disagree on the anti-baffle sentiment, the kids could learn a lot in general. After all, that's the purpose of the entire project, isn't it?
Dec. 2, 2010 9:01 p.m. Nashco SuperDork

Thousands of people autocross their mostly-stock cars every year with stock oil pans and the engine doesn't mind a bit. If you were putting some R-comps on it and taking it on a road race course for 30 minutes, then a baffle might be necessary...but you're not.

Bryce
Dec. 2, 2010 9:44 p.m. MrBenjamonkey HalfDork

Nashco wrote:

Thousands of people autocross their mostly-stock cars every year with stock oil pans and the engine doesn't mind a bit. If you were putting some R-comps on it and taking it on a road race course for 30 minutes, then a baffle might be necessary...but you're not.

Bryce

Actually I am ...
Dec. 2, 2010 9:46 p.m. MrBenjamonkey HalfDork

chknhwk wrote:

I disagree on the anti-baffle sentiment, the kids could learn a lot in general. After all, that's the purpose of the entire project, isn't it?

I'd be lying if I said there wasn't a small desire somewhere in the back of my head to make a cool track car in the process, but yes, you're absolutely right.

I'm going to try and keep the 1.5L. Maybe next year we can build it into a turbo motor.
Dec. 3, 2010 5:17 a.m. tuna55 Dork

Sounds like a good plan. Make sure they are there for the inevitable dirty grimey greasy disassembly too. Make them get their hands dirty and make them scrape gaskets. It's all part of how much you want them to appreciate it when it starts up again.

And I am total pro-baffle. A dyno operator told me once that he has seen more gains from oil pans than a bunch of more likely stuff.
Dec. 3, 2010 5:25 a.m. Tom Suddard SonDork

MrBenjamonkey wrote:

Tom Suddard wrote:

I don't see anything wrong, it looks good. How accurate are the balances you have access to?

I don't have a balance. I have scales.

I was planning to hang one end of the rod from a fixed height relative to the scale and weigh the other end. I would then swap ends, record both weights and make them all match.

Like this:

That's what I thought you were doing. I assumed you were talking about this kind of balance:
Dec. 3, 2010 8:39 a.m. iceracer Dork

Fab up a windage tray while doing the baffles. Restrict the oil supply to the head.