Super Chevy comes through again...

[Ken]

The October issue of Super Chevy magazine has a tech article entitled: "12 Engine Building Tips" by Wayne Scraba.

I'm only going to pass on a few of 'em, because I suggest you go out and buy a copy (Better yet, subscribe - it's cheaper .

Grumpy, if you see this, what do you think of the following: (Bear in mind it's talking about race engines, more or less)

Fresh Firing Orders

A typical Chevy firing order is 1-8-4-3-6-5-7-2 9 (aside from the late-model LS-series engines). For the vast majority of applications, this firing order works very, very well. So well, there's likely no need to change it. But in high performance (race or otherwise) application, there may be sufficient power available from different firing orders to warrant a change. For example, there are seven other firing order arrangements that can be used without changing the crankshaft layout. These firing orders include the following:

• 1-8-4-2-6-5-7-3
• 1-8-7-2-6-5-4-3
• 1-8-7-3-6-5-4-2
• 1-5-4-3-6-8-7-2
• 1-5-7-3-6-8-4-2
• 1-5-7-2-6-8-8-3
• 1-5-4-2-6-8-7-3

Reher-Morrison has tested the various combinations, and has found some interesting results. When the firing order is revised to 1-8-7-3-6-5-4-2, you'll find some power and reliability. Now, if you race a Pro Stock car, this is no secret since the revised order has been in vogue for some time, but to the little guys it's also important. You see, with the revised firing order, fuel distribution dilemmas are resolved. The engine tends to run cooler, and perhaps just as important, the engine is actually smoother. How much extra power is there? Anywhere between 8-10 measureable horsepower. In a well-sorted engine, that's a bunch. There was once a caveat here though: The average racer couldn't easily get a cam with the revised lobe positions. Not so today. Reher-Morrison sells such a package ("Big Stick Cams") for Chevy big-block/Big Chief head combinations.

I learn something new every day. :gap

They also have these tid-bits which I find interesting:

Blue By You

According to the folks at Fel-Pro, the Blue Stripe on Fel-Pro gaskets is a registered trademark and does not indicate the top or bottom of the gasket. Make sure to follow directional stamps and/or the instruction sheet for proper gasket positioning.

Plug Heat

In a Chevy engine that is modified (and particularly if the engine has an increased compression ratio) more heat is a byproduct of the added power. That should be no secret. But what's the correct spark plug heat range for something like this? Here's a simple rule of thumb: Use one heat range colder for every 75-100 hp you add, or when you significantly raise the compression ratio.

Filter Folly

Spinning off a used oil filter on your Chevy almost always creates a major mess. One way to stop the mess is to slip a plastic bag over the old filter after breaking it loose with a filter wrench. Then with one hand, hold the neck of the bag tight against the engine block, and use the other hand to unscrew the filter. The dirty, hot oil will be contained within the plastic bag, and it won't run down your sleeve.

Super Chevy magazine has a lot of good stuff every month. Check it out y'all.

 

[MaineShark]

Lots of interesting stuff...

Particularly the 7/4 firing order swap. Does anyone make SBC cams with that change?

Joe

 

[Ken]

Can't answer that one - don't know. That was the first I heard of the firing order changes being possible, but then, I discovered today through my mechanic (he's had a few hot Fords) that Ford does that with some of their V-8s.

_ken