Yellow Bullet Forums banner

1 - 16 of 16 Posts

·
Registered
Joined
·
2,435 Posts
Discussion Starter #1
So I was curious if you could angle mill 23* heads down if so how far. I would think you could mill the head surface down some to make some more power but then take intake and exhaust back to correct angle so not to mess with intake or headers.

Is this possible or not worth the work?
 

·
Registered
Joined
·
7,657 Posts
I have had 2 sets of SBC factory heads angle milled, one @ 0-0.080" & the other 0-0.125".I would think with all the extra deck thickness claimed currently by manufacturers that this figure may be able to be exceeded. Yes this is possible as to whether it is worth the work I can't really say as everyone has a different view. Mark
 

·
Registered
Joined
·
1,196 Posts
With welding I have seen 0-.200
 

·
Registered
Joined
·
508 Posts
Its a great way to reduce chamber volume quickly for higher CR. Its very common to angle mill a high effort set of chevy heads 1*. Depending on the int valve size. If using a 2.125"valve, sometimes your limited to only a 1/2* then an additional .020"or so flat milled.
You only need to correct the intake fact, not the exh.

Mike Theroux
www.mikesportingservice.com
 

·
Registered
Joined
·
2,700 Posts
My Dart Pro1 CNC heads were angle milled .100. Then the intake side had to be squared up. And I had pistons specifically designed to match. Had to use thick intake gaskets due to spacing issues.

But it makes and difference.
 

·
Registered
Joined
·
35 Posts
you can open a can of worms angle milling heads,my alum bowties i had to re drill head bolt holes and reface the bolt head surface,valve train geometry,push rods,had to mill intake face and ends also slot intake bolt holes.
the worst part is try and resell this kind of work when you want to upgrade,just kills the resale value,
best of luck however you decide,
 

·
Registered
Joined
·
6,312 Posts
The dirt tracks around here all require flat top pistons in the fast full bodied classes but they have no CC rule on heads. We have been angle milling the SBC heads .125 for years. Just spot face the bolts and redrill the pushrod holes. They do tend to crack with time. It costs alot to do this and I often ask why not just allow pop top pistons and do a CC rule. But guess who techs the motors and makes the rules? The motor builders and who makes money angle milling heads?
 

·
Registered
Joined
·
2,435 Posts
Discussion Starter #10
Thanks guys I was not sure if the gain was worth the work. Sounds like your better off to just buy a set of pistons and good heads to start
 

·
Registered
Joined
·
373 Posts
Thanks guys I was not sure if the gain was worth the work. Sounds like your better off to just buy a set of pistons and good heads to start
Doesnt the flat top burn alot cleaner and the shallower chamber make for a better quench? PLUS a fresh set of pistons will cost more in the long run due to possible rebalance along with a extra 800.00 for pistons which might be heavier..:mad:
 

·
Registered
Joined
·
22 Posts
There is a circle track engine builder in Rutherfordton NC that angle mills the dart iron eagle heads 0 to .385.He says the chambers are around the 33 to 34 cc range.Last time I seen a post about it he said it took around 40 hrs just to mill them.His name is Bill Hendren of Hendrens Racing Engines.
 

·
Registered
Joined
·
4,501 Posts
The AFR 227 heads we have done were 0-.125 then .040 flat milled for a 57cc chamber. With more flat milling over time we get down to 53cc.

Our SB2 heads have big chambers (Truck Heads) and have 46cc chambers.
 

·
Registered
Joined
·
126 Posts
i think my heads have already been done like this because my intake leaks on the bottom of the ports i have have had it cut .035at the top and it still leaks should i notch the bolt holes and try it or cut it again
 

·
Registered
Joined
·
1,643 Posts
you can open a can of worms angle milling heads,my alum bowties i had to re drill head bolt holes and reface the bolt head surface,valve train geometry,push rods,had to mill intake face and ends also slot intake bolt holes.
the worst part is try and resell this kind of work when you want to upgrade,just kills the resale value,
best of luck however you decide,
any experianced machine shop would not just angle cut the heads and say the rest is on your own. we angle cut them then cut the intake side and end by spot facing the bolt holes. the intake is still in the correct location as long as the intake rail/head surface was cut correctly.
 

·
Registered
Joined
·
7,657 Posts
Question to those who say that they have noticed a performance difference. I would like to ask How much difference improvement or not? Also exactly how was the testing performed so as to isolate this to the angle milling other than the obvious gain through increased compression?
 
1 - 16 of 16 Posts
Top