Does anybody know how well these heads flow compared to other years?
If someone can post a flow sheet I would appreciate it.

Are most heads measured with a pipe or without? I have seen head flow numbers for 95 heads but there was no mention of pipe size if any was used and no mention of " H20?

So I guess if someone can post both for comparison that would be great!

 

There is not going to be a huge difference in head flow numbers between years on LT1 heads. The only difference in flow is going to be the aluminum versus iron heads with the iron heads flowing about 20% more. Here is a link showing stock LT1 head flow data. Scroll down

http://chevyhiperformance.com/techar...98/index4.html

 

I thought one Aliminum LT1 head is better than the other for porting.

 

The 561 castings (97 heads ) do in fact flow better than earlier LT1 aluminum heads. The 561 casting flows as well as the LT1 iron heads. The draw back with the 561 casting is they are not as well suited for porting as the earlier aluminum heads

 

yeah, I was told the 561 flow better in stock form but I need the flow numbers for the cam grinder. Maybe Lloyd has a flow sheet for them?

 

I would suggest using a grinder who knows the LT1 well enough to not have to ask for stock head flow numbers. Granted the LT1 is very similar to gen1 motors but the intake in particular moves the powerband and the extra compression helps things as well. If he is accustomed to gen1 stuff and can not take these things into consideration you will not be getting the advantage you should from a more custom cam.