What's the difference in porting and milling heads?

Reply Subscribe

Thread Tools

Search this Thread

Jun 3, 2010 | 08:22 AM

Blue_GTO1199

Thread Starter

Teching In

iTrader: (1)

Joined: Aug 2009

Posts: 15

Likes: 0

What's the difference in porting and milling heads?

I found a set of milled 243's on craigslist for $300. I'm interested, but what exactly IS milling? Is it better than porting?

Jun 3, 2010 | 08:30 AM

ttranssam

TECH Fanatic

iTrader: (10)

Joined: Oct 2007

Posts: 1,388

Likes: 0

From: plainfield,IL

Milling is shaving the whole bottom where the head meets the deck of the block. It lowers the compression adding a lol power. Porting heads is the inside runners and chambers getting cleaned and smoothend for better air flow

Jun 3, 2010 | 08:34 AM

Blue_GTO1199

Thread Starter

Teching In

iTrader: (1)

Joined: Aug 2009

Posts: 15

Likes: 0

Quote:

Originally Posted by ttranssam

so if heads are milled, will they fit right on to my block, or do i need to do something else?

Also, is milling better than porting then?

Jun 3, 2010 | 08:40 AM

smg267

TECH Resident

iTrader: (23)

Joined: Apr 2006

Posts: 986

Likes: 1

From: PA

I would be careful and ask what they are milled to. You could run into PTV problems.

Jun 3, 2010 | 08:41 AM

ttranssam

TECH Fanatic

iTrader: (10)

Joined: Oct 2007

Posts: 1,388

Likes: 0

From: plainfield,IL

milling will yeild some hp but porting i think will get you more. and yes they will fit fine...milling trues the surface area too.

Jun 3, 2010 | 08:42 AM

ttranssam

TECH Fanatic

iTrader: (10)

Joined: Oct 2007

Posts: 1,388

Likes: 0

From: plainfield,IL

oh yea^^^ if you go with any aftermarket cam you have to watch your PTV pistion to valve clearance due to the heads being milled.

Jun 3, 2010 | 08:43 AM

Blue_GTO1199

Thread Starter

Teching In

iTrader: (1)

Joined: Aug 2009

Posts: 15

Likes: 0

Quote:

Originally Posted by ttranssam

oh yea^^^ if you go with any aftermarket cam you have to watch your PTV pistion to valve clearance due to the heads being milled.

That's what i'm worried about...

Trending Topics

LT1 camero. Fastest stock NA pony car ever?

927

23.8k
650/700 RWHP how streetable is it with a PD Super Charger?

11

254
Conical air filters

8

166
Parts blow out!!! Ls1 ls2 ls3 ls7

9

433
Oil pan sucking Dry?

23

724

Jun 3, 2010 | 08:45 AM

Blue_GTO1199

Thread Starter

Teching In

iTrader: (1)

Joined: Aug 2009

Posts: 15

Likes: 0

ok, it says they were milled to 59cc

i'll have a comp 228/230 .571/.573 112lsa cam in there.
will that work?

Jun 3, 2010 | 08:46 AM

snake95

Staging Lane

Joined: Aug 2009

Posts: 84

Likes: 42

From: Rent Free in Hio's Mind

Quote:

Originally Posted by ttranssam

I'm sure it was just a typo, but milling raises your compression.

Jun 3, 2010 | 08:48 AM

#10

ttranssam

TECH Fanatic

iTrader: (10)

Joined: Oct 2007

Posts: 1,388

Likes: 0

From: plainfield,IL

your going to need to get them checked...you can do a play-doh job on it...put the heads on with two small strips of play-doh over the piston where the valves would hit and turn the motor over...thats the gettho way...

Jun 3, 2010 | 08:50 AM

#11

ttranssam

TECH Fanatic

iTrader: (10)

Joined: Oct 2007

Posts: 1,388

Likes: 0

From: plainfield,IL

^^^woops my bad. im buildin a turbo car so the last few weeks for me everything is about lowering my compression...lol sorry

Jun 3, 2010 | 08:52 AM

#12

Blue_GTO1199

Thread Starter

Teching In

iTrader: (1)

Joined: Aug 2009

Posts: 15

Likes: 0

there's also a guy selling ported and milled 853's for the same price.

he says they were milled .015 and ported to add 50cfm as proven on the superflow 600 flow bench

Jun 3, 2010 | 08:55 AM

#13

ttranssam

TECH Fanatic

iTrader: (10)

Joined: Oct 2007

Posts: 1,388

Likes: 0

From: plainfield,IL

853s are kind of junk...there the second worse head you can get. id shoot for some 243s or 799s them in stock form are way better then 806-853-241s...

Reply Subscribe