Straight cut cam gear or OEM for my new engine ?

[SMO]

Yes..and same question.. why build  2332cc when you can build 2387cc ? 

Increasing the stroke will lessen the cross section that the main journals and rod journals share, weakening the crankshaft. Also, smaller stroke engines are narrower (closer to stock) so the sheetmetal fits nicely with no gaps, and the pushrods are shorter (lighter and will deflect less... slightly more valve lift). When you go past 82mm it is also advisable to increase rod length so your pistons dont hit the crankshaft and so you have an acceptable rod ratio. Increasing rod length increases the width of the motor even more, not to mention the extra weight of a longer rod. Not to mention the extra clearancing to the case and camshaft that is necessary with extra long strokes.
In my opinion, a 2276 is a perfect engine. Use short and light 5.325" H-beam rods on an 82 chevy journal crank, that gives you a very nice 1.649:1 rod ratio, a stout crank, and an engine that ends up slightly narrower than a stock 1600 with a pump gas friendly compression ratio around 9:1.

Yes 2276 is a very nice engine. 84mm stroke and 5,7" rods will give me a rod ratio 1,723:1 which is also good, You should have rod ratio around 1,7. Long rods give you a better angel when the pistons are in BDC. And long rods give you more torque, less side power on rods and crank.

[Zach Gomulka]

Yes 2276 is a very nice engine. 84mm stroke and 5,7" rods will give me a rod ratio 1,723:1 which is also good, You should have rod ratio around 1,7. Long rods give you a better angel when the pistons are in BDC. And long rods give you more torque, less side power on rods and crank.

Agree to disagree

How accurate and how noisy they become is up to the machining of you engine case. VW and Empi made different gears for different occurring spacing between cam and crank.... nowadays this option is gone. So its now just down to luck.

Check out this box from Empi, thirteen different sizes... talk about a quality product...  today one size fits all...

I dont think that is a straight cut gear. Helicut gears need all the different sizes, just like stock.

[Jon]

I dont think that is a straight cut gear. Helicut gears need all the different sizes, just like stock.

No, Its not a straight cut gear, but this illustrates a point. There are several  different measurement between the crank and the cam. From what little I learnt at school about designing gears, I can't remember a straight-cut gear to be considered a universal fit.  What I´m trying to get across is that the fit doesn't come with the brand, it comes with your case.

[Jordy/DVK]

Yes 2276 is a very nice engine. 84mm stroke and 5,7" rods will give me a rod ratio 1,723:1 which is also good, You should have rod ratio around 1,7. Long rods give you a better angel when the pistons are in BDC. And long rods give you more torque, less side power on rods and crank.

 More important!!! Long rods don't make the piston accellerate as much as short rods do. Long rods make the piston accellerate and brake more smoothly.
 Faster accelleration (also more mass: therefore use the lightest as possible of everything) greatly increases the stresses and strains on bearings and rods and it consumes power.
 Especially when you're running high RPM's... The longer the rods, the smoother the accellerations inside, the smaller the internal forces, the more useful HP out of your engine...