I have a couple of engine cases sitting around that I'd like to build into complete engines while my little old worn powerplant (when the oil's hot the oil light will sometimes turn on at low idle. I'd better do something about that, huh?) will still push me down the road.

(Old east German joke: why is the Trabant's engine in the rear? To keep your hands warm while you push it)

OK, so I need to figure out what to build. I'd like something with a little more go power than the stock 1.6, but it doesn't have to be much. Since I'd like a little more low-end torque, it seems to me that I might build a mostly-stock engine with a 74mm crankshaft. But that would change the compression ratio.  I don' t think that I would want to change the camshaft in it. I'm not looking for a "screamer" engine or a "freeway flyer" or anything. Mild street at most, perhaps.

1. Am I missing something important here? What besides compression ratio (which I'd like to keep basically the same) do I need to consider if I install a stroker crank?

2. How do I lengthen the stroke yet keep the compression ratio at 8:1?


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First off I'd suggets you go with at least a 78mm stroke.  The cost difference is nill and it's actually easier to do.  Using either a 74 or 76 stroke crank will force you to use 'A' pistons which means large spacer.  That in turn means a wide engine,, which means exhaust fits funny, tins fit funny,, everything is gonna need work above and beyond a 'normal' build.

Next, you really want a new case when you're thinking of a performance build.  The only alternaitive is if you know the entire history of your current case and it's been throughly looked over.  For example, I just recently had to junk a case that bought new a few years ago, it was just too far gone to put back into service.

Cam, I'd recommend against a stock cam in a stroker, you will absolutely hate the power band, it'll be over sooner than a stock engine.  The stroker wants more air (displacement) yet you're still providing it with the same amount as you would a stock engine by using a stock cam.  With that comes carbs, duals are the way to go here.  With a mild cam like an Engle 110 (min, I'd actually say a 120 or k8) you could go with dual 40s.  With a larger cam then 44s are a good choice, 48s if you really want to open it up.

Compression ratio depends on way too many things.  Pick a cam, heads, level of port work, carbs, exhaust, etc, and then think about compression ratios.

On the other hand, if you're just looking for a good solid reliable fun to drive, easy to build, low maintanance engine.  It's hard to beat a 1776 with a 110 cam and dual carbs and a 1 1/2" merged header.  Set the compression to 8.0 and you'll be happy.  -Ryan

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