Lots of snow so starting porting some heads

[efnfast]

Do we know this helps, or do we (like the way I say we?) figure it can't hurt?
Thanks for the education. -Steve

[LGAFF]

Probably 10hp maybe alittle more

[efnfast]

Originally Posted by LGAFF

Probably 10hp maybe alittle more

Just from unshrouding?

[LGAFF]

yes

[Paul Workman]

Originally Posted by LGAFF

Basically the the edges of the combustion chamber(clover leaf) sit too close to the valve edges, this impedes flow, removing material from the edges allows more flow, although it also reduces compression somewhat.

The question is, is the clover leaf design the most efficient or is a hemi design better. Not sure if the clover leaf was more about meeting CAFE and running 87 octane or performance

Hemi's don't lend themselves to more than 2 valves, for one thing. 4-valve chambers use the "pentroof" design: small = less heat loss, higher compression, faster flame front...

http://www.howstuffworks.com/hemi2.htm



P.

[LGAFF]

Intake ports are pretty much done, need to smooth out a few things; exhaust should be done tomorrow:

[LGAFF]

[LGAFF]

[LGAFF]

[LGAFF]

As stated, this is a head I picked up for about $200 a few years ago, so I thought I would learn the ins and outs with this one. Porting these is like tiptoeing through a minefield, at least for a beginner(me). Traditionally, the neck behind the valve bowl is an area to work..in the LT-5 I found out the material is thin. In my first port I hit a water jacket that in the normal head would not have been an issue....this will be easy to fix with welding. After that the porting was uneventful until the 2nd to last runner.

I marked this area on the photo below as "thin"....this is the transition from the thick Aluminum flange were the IH bolts, into the area the opens ups for the valve train. As I was porting, I hit this area...what was odd is that the material around it was very thick still, almost as if I hit a small defect or void. I can access the runner from the backside and it opens to oil vapor, should be an easy fix. This area was well before and off to the side of the area were the lifter sits.

I had no issues avoiding the lifter area....