I always used a STD bearing in my engine.

I see there is some trick narrowed bearings. Why should i stay with STD or stay away from Std clevlites?

Going into a 1000hp (on N20) 468 engine. Streetracing only.

Are those narrowed bearings for cranks with big fillets? Do you have one of those cranks?

Im pretty sure it has to do with your crankshaft. Most after market cranks have a different radii, needing the different bearing. Your crankshaft manafactuer should recomend the proper bearing.

i have a Crower Pro stock crank from the mid 70:is

They dont have any facts on them. I have to ask my machinist. But i used stock for 5 years now. Hope thats the right one ;)

It has a "T0721" stamped on it?

bring it to a machinist who grinds cranks and have him measure the radii.

Narrowed bearings are for cranks with large fillet radii.

I would suggest you have a professional engine builder, with a history of good work, put this motor together for you.

I have.

But i order the stuff and he assembles. And if i order wrong stuff he just send it back to me and i have to send more things overseas.

,)

If you are using the std P type Clevite bearings & they are not showing signs of rubbing on the outside edges & you are not "flaking" the surfaces then you should be fine except I don't believe the std P style was ever designed to handle 1000hp. :D
The performance bearings from Clevite like the H style bearing is chamfered for a larger radius in the crank & is also a better meterial for a performance engine as are the Fed Mog Performance bearings. They are designed to take more load & are probably what you should be using because of the power level you are planning

If you go to the H style or the Federal Mogul bearing be aware that they are "ugly" out of the box. This is the way they are supposed to look so don't be alarmed ;)
There are other performance bearings like King & I believe ACL has some but I haven't used them so I can't really comment except to say I have not heard anything bad about them & that always seems to be the first thing you hear :(

Cant be that good using chamfered bearings on a crank that not ground for that?

It is no problem at all, the chamfer doesn't effect the bearing. It is quite small & the rods are still what sets side clearance.

What about the bearings with performance coatings? Worth it?

Jeff,
Coatings on bearings look awesome, but there has been no benefit found in our testing. Depending upon the coating, there may (theoretically) be some very slight benefit when the engine is first started, before oil pressure is built up. Once the engine has oil pressure, there is a "wedge" of oil between the crank pins and the bearing surface, therefore coatings are of no consequence at this point. Testing many variations of engines through repeated dry starts has not resulted in any improvement in bearing life when a coated bearing is used, but there are many people who are very emphatic about using coated bearings.

You guys have right. Again... I used wrong bearings the 2 last times. ;(

But nothing has wrecked ,)

Thanks again...