When referring to engines, what does the angle mean?

[lemming303]

Like if you said "a 59 degree W9 engine". What does that mean?

[the_engineers]

It is the lifter angle in the lifter valley.  Stock SB Chrysler lifter angle (59*) puts a tall lifter (roller) almost into the side of the valley, so the fix is the 48* block which straightens out the angle and allows truer valve motion.  The angle change requires a custom cam amongst other issues.

[dodj]

I think it refers to the angle between the left and right bank of cylinders. A 90 degree block would have the left and right bores at right angles to each other. A 60 degree block would be narrower but taller, a 120 degree block would be wide but not very tall.

At least thats what I thought it meant until I read The Engineer's reply. We could be talking about two different things that are both measured in degrees?!?

[tommyg29]

Its like my 12th grade physics teacher once wrote on the board:

After none of us could figure it out, he translated it as:
the angle of the dangle, times the torque of the pork, divided by the mass of the ass = the integral of e to the x. Or, if you've got a juiced big block, you need a Dana 60.

[matt63]

I'm going with the lifter angle answer.    Yes, for V8s the angle between the cylinders is sometimes mentioned when talking about design.  For small block Mopars however, I believe it is the lifter bore center lines because of their poor stock geometry.  The race blocks rectify this deficiency.  That's my theory. 

[dodj]

Its like my 12th grade physics teacher once wrote on the board:

After none of us could figure it out, he translated it as:
the angle of the dangle, times the torque of the pork, divided by the mass of the ass = the integral of e to the x. Or, if you've got a juiced big block, you need a Dana 60.

That pretty much says everything you need to know!

[gkring]

lifter angle is correct in your example. The W9 refers to the type of head. There are W2, 5, 8, 9 and various versions of each.
http://www.moparmusclemagazine.com/techarticles/engine/mopp_0310_340_engine_600_hp/index.html
http://www.moparts.org/Tech/Archive/smallblock/23.html

[71chally416]

The "LA" small block retained the lifter angle of the original Hemi, which is why it is not ideal for a Wedge motor. And not all race blocks have the improved lifter angle.

[lemming303]

So what difference is a Wedge motor? I thought it was just a series of engines, like LA.

[moper]

Yes, lifter angle... "wedge" is a marketing name like Hemi only it means "non-hemi" shaped cylinder heads. Techincally speaking, the small block fords, SB Chevies, and anything else not using a central spark plug and in line valves is a "wedge". LA refers to the head design. So you have LA wedges, 318 Polyshperes, and Magnums(which are also wedges but use a different more modern port/chamber layout) for small blocks.

[Chryco Psycho]

 
 the small block doesn`t have the lifter angle straight with the pushrod , , the lifter leans more outward , the race blocks offer the improved lifter angle keeping the lifter & pushrod straight
 the wedge was just an nickname for the Wedge style head / combustion chamber angle to the piston

[Changin Gears]

But for 99.99% of engine builds this number is meaningless because its a stock block.

[lemming303]

Thanks yall.

ChanginGears, that's a pretty cool pic in your signature line. Looks like that trans completely blew up. Bet that was pretty crazy....

[HP2]

Yes, lifter angle... "wedge" is a marketing name like Hemi only it means "non-hemi" shaped cylinder heads. Techincally speaking, the small block fords, SB Chevies, and anything else not using a central spark plug and in line valves is a "wedge". LA refers to the head design. So you have LA wedges, 318 Polyshperes, and Magnums(which are also wedges but use a different more modern port/chamber layout) for small blocks.

I think you nailed it all except LA. LA was the block designation, or Lightweight A, B  the big block, and RB the Raised Block. All of these used wedge heads.  The later Magnum headed (still a wedge head) engines were still using LA blocks.