Chalenger v8

[gabedrummin]

I got my plans for the v8 from coles .I have some questions about how the cam lobes are machined are they 90 degress from each other following the fireing order.... Say number 1 cyclinder fires first machine the number one cam lobe at 0 degres .If number 6 was to fire next index to the number six cam lobe location turn cam 90 degres and machine that lobe....Is this thinking correct....one other problem I see is the blower case is dimensioned /////.100 longer than the blower rotor..I think rotor end clearance should be held to .001 or less .Whats you thoughts....? Thanks
Attached is pic of proposed crank.

[stevehuckss396]

Originally Posted by gabedrummin I have some questions about how the cam lobes are machined are they 90 degress from each other following the fireing order.... Say number 1 cyclinder fires first machine the number one cam lobe at 0 degres .If number 6 was to fire next index to the number six cam lobe location turn cam 90 degres and machine that lobe....Is this thinking correct....

That logic would work only if it were a straight 8. Take the Chevy V8 for instance. Firing order is 1-8-4-3-6-5-7-2. You get a fire every 90 degrees. If No1 is at 0 degrees then No8 is 90 degrees behind No1 and 90 degrees behind in firing order so the lobes would need to lag by 180 degrees. The cam spins half as fast as the crank so the lobes would lag by 90 degrees on the shaft.

It gets a little confusing because you need to consider the 2 banks are 90 degrees apart and the cam spins slower than the crank. I have to sit down and figure out the chevy firing order because I am also doing a small V8. We are in the same boat. When my table is complete it will be posted at mickey's website for anybody to use.

See if these help

http://www.mikes-models.com/camarticle.html

http://www.mikes-models.com/camshafts.html

[gabedrummin]

Thanks ./.the crank making two revs to the cam making one is messing me up too. This is based on a crank like the one in my pics. If it is a flat crank that changes thing again correct...?

[stevehuckss396]

Originally Posted by gabedrummin Thanks ./.the crank making two revs to the cam making one is messing me up too. This is based on a crank like the one in my pics. If it is a flat crank that changes thing again correct...?

Not sure a flat crank would work in a V8. The one in your photo is the one I would use.

Also you need to consider the direction of rotation of the cam. Some are clockwise and some are counter clockwise.

[dynosor]

Originally Posted by stevehuckss396 Not sure a flat crank would work in a V8.

Some Ferrari V8 cranks are "flat" for more even power pulses.

http://en.wikipedia.org/wiki/V8_engi...nkshaft_design

YouTube- Flat Plane Crank w/Rods & Pistons

[stevehuckss396]

Originally Posted by dynosor Some Ferrari V8 cranks are "flat" for more even power pulses. http://en.wikipedia.org/wiki/V8_engi...nkshaft_design YouTube- Flat Plane Crank w/Rods & Pistons

I had no idea!! Thanks