Aluminum vs stamped breathers

[fxstdavew]

I don't remember why the aluminum ones were changed to stamped steel but there is there a benefit to one over the other

[Ohio HD]

I honesty think that the stamped steel units were a cost savings part. Cheaper than a casting then machined part. I don't know that there's any functional difference.

[kink04fxd]

When I did my top end I used the stamped units. IMO, I think they work better than the alum ones.

[Rockout Rocker Products]

If you go from cast to stamped make sure you get the whole kit with the shorter bolts. Using the longer original bolts with stamped breathers can crack your heads. Along the same line... completely blow or swab out any oil from the holes or it will have nowhere to go.... 

[fbn ent]

If you go from cast to stamped make sure you get the whole kit with the shorter bolts. Using the longer original bolts with stamped breathers can crack your heads. Along the same line... completely blow or swab out any oil from the holes or it will have nowhere to go.... 

Hmm...now you have me wondering. Can you remember the length of either the old ones or the new ones?

[billbuilds]

If you go from cast to stamped make sure you get the whole kit with the shorter bolts. Using the longer original bolts with stamped breathers can crack your heads. Along the same line... completely blow or swab out any oil from the holes or it will have nowhere to go.... 

Hmm...now you have me wondering. Can you remember the length of either the old ones or the new ones?

     I have an unopened packaged of the stamped ones and they're 1-5/8" in length.

[Rockout Rocker Products]

Google shows 2-1/4 for the old style.

[Rockout Rocker Products]

Another caution...

I'll just leave this right here.

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[Ohio HD]

4400
late bolt
1/4-20 X 1-11/16 hex flange head grade 8


3746A
early bolt
1/4-20 X 2-1/4 hex flange head grade 8

[itsafatboy]

this company makes great breathers ,  i use their comp releases and they are best,

https://secure.vulcanworks.net/store/

i ended up getting the SS die cast rocker covers for two reasons they have a simple breather setup, and the hole in middle of rocker box releases a lot of heat from heads, then i use two crank vents off heads and breath to a little KN filter works great.