Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
GL4x4 Live! GL4x4 Casino







Search
Reply
 
Thread Tools
Old January 3rd, 2012, 02:58 PM   #1
chadcooper55
expert jeep disassembler
 
chadcooper55's Avatar
 
Join Date: 08-28-08
Location: kent city mi
Posts: 8,026
iTrader: (20)
Mentioned: 9 Post(s)
Default 5.3 heads

Are 1999 5.3 heads worth a crap for performance? Will they bolt onto a 6.0? I have a set and was wondering if it was worth porting and polishing to put on a 6.0.
__________________
I hate being bipolar, its great!

jeep turned buggy now back to jeep
http://www.greatlakes4x4.com/showthread.php?t=175584
chadcooper55 is offline   Reply With Quote
Old January 3rd, 2012, 03:11 PM   #2
montecarlo33
The Violator
 
montecarlo33's Avatar
 
Join Date: 08-23-07
Location: Otsego County 49735
Posts: 4,315
iTrader: (18)
Mentioned: 1 Post(s)
Default

862's I imagine? They would bolt up to a 6.0 but Im not sure that it would gain you anything over stock 6.0 heads that would make the money worth the while.
montecarlo33 is online now   Reply With Quote
Old January 3rd, 2012, 03:16 PM   #3
chadcooper55
expert jeep disassembler
 
chadcooper55's Avatar
 
Join Date: 08-28-08
Location: kent city mi
Posts: 8,026
iTrader: (20)
Mentioned: 9 Post(s)
Default

Quote:
Originally Posted by montecarlo33 View Post
862's I imagine? They would bolt up to a 6.0 but Im not sure that it would gain you anything over stock 6.0 heads that would make the money worth the while.
I have never ported and polished heads before but i would like to try it. Just figure if they aren't terrible heads I would do it to them. I'm not out anything if I fukc it up and I could always put the stock heads back on the motor.
__________________
I hate being bipolar, its great!

jeep turned buggy now back to jeep
http://www.greatlakes4x4.com/showthread.php?t=175584
chadcooper55 is offline   Reply With Quote
Old January 3rd, 2012, 09:36 PM   #4
vickiebrian
Senior Member
 
vickiebrian's Avatar
 
Join Date: 03-22-09
Location: delton/mi
Posts: 143
iTrader: (4)
Mentioned: 0 Post(s)
Default

I have a set going on my new motor had the machine shop open up for 6.0 intake valves I believe the added compression is worth more than the flow gained from 6.0 heads in useable power that the motor will see.
vickiebrian is offline   Reply With Quote
Old January 6th, 2012, 11:57 AM   #5
montecarlo33
The Violator
 
montecarlo33's Avatar
 
Join Date: 08-23-07
Location: Otsego County 49735
Posts: 4,315
iTrader: (18)
Mentioned: 1 Post(s)
Default

Quote:
Originally Posted by vickiebrian View Post
I have a set going on my new motor had the machine shop open up for 6.0 intake valves I believe the added compression is worth more than the flow gained from 6.0 heads in useable power that the motor will see.
Probley just like throwing 305 heads on a 350 does the same for a bump in compression.
montecarlo33 is online now   Reply With Quote
Old January 6th, 2012, 12:41 PM   #6
2000_WJ
Senior Member
 
2000_WJ's Avatar
 
Join Date: 04-14-09
Location: Keego Harbor, MI
Posts: 589
iTrader: (10)
Mentioned: 0 Post(s)
Default

They could be 706 castings also. What head castings are on your 6.0L 317?. 5.3L heads dont flow as well as a 243 head, they are similar in flow to a 853 but have smaller combustion chambers. These heads with the LS6 valves, porting and decking used to be the standard for 3rd gen LS cam and head cars.
2000_WJ is offline   Reply With Quote
Old January 6th, 2012, 01:10 PM   #7
chadcooper55
expert jeep disassembler
 
chadcooper55's Avatar
 
Join Date: 08-28-08
Location: kent city mi
Posts: 8,026
iTrader: (20)
Mentioned: 9 Post(s)
Default

I haven't bought the 6.0 yet, I am still researching. I will check the 5.3 heads when I get home, I am in Colorado working right now.
__________________
I hate being bipolar, its great!

jeep turned buggy now back to jeep
http://www.greatlakes4x4.com/showthread.php?t=175584
chadcooper55 is offline   Reply With Quote
Old January 6th, 2012, 02:44 PM   #8
Haggar
Covered in mud...
 
Haggar's Avatar
 
Join Date: 11-06-05
Location: Oxford, MI
Posts: 17,551
iTrader: (54)
Mentioned: 1 Post(s)
Default

Yeah, those are 'standard' 5.3 heads, they'll bump compression. Its a popular option on 6.0s, once ported. A lot of companies sell ported 5.3s as cheap performance heads.

later high output Gen III and Gen IV 5.3s have better heads, the 243 / 799 heads (so called 'LS6' or LS2 heads). They flow better but don't do the same bump in compression.

You can also mill them for more compression. With any of the heads, especially since all of these are smaller valve catherdral port heads.

The 6.0 heads flow well, but have a larger chamber volume. So milling those and doing a P&P might be another option.


The hot ticket (but takes some money) is putting L92 square port heads (about $900 a pair), and matching intake.
Haggar is offline   Reply With Quote
Old January 6th, 2012, 08:19 PM   #9
chadcooper55
expert jeep disassembler
 
chadcooper55's Avatar
 
Join Date: 08-28-08
Location: kent city mi
Posts: 8,026
iTrader: (20)
Mentioned: 9 Post(s)
Default

Quote:
Originally Posted by Haggar View Post
Yeah, those are 'standard' 5.3 heads, they'll bump compression. Its a popular option on 6.0s, once ported. A lot of companies sell ported 5.3s as cheap performance heads.

later high output Gen III and Gen IV 5.3s have better heads, the 243 / 799 heads (so called 'LS6' or LS2 heads). They flow better but don't do the same bump in compression.

You can also mill them for more compression. With any of the heads, especially since all of these are smaller valve catherdral port heads.

The 6.0 heads flow well, but have a larger chamber volume. So milling those and doing a P&P might be another option.


The hot ticket (but takes some money) is putting L92 square port heads (about $900 a pair), and matching intake.
So bang for my buck It would be worth doing a little work on the 5.3 heads? I want to build a budget performance 6.0. Nothing extreme but I would like it to be peppy. Spending less on the motor makes it easier to swallow the price tag for an atlas.
__________________
I hate being bipolar, its great!

jeep turned buggy now back to jeep
http://www.greatlakes4x4.com/showthread.php?t=175584
chadcooper55 is offline   Reply With Quote
Old January 13th, 2012, 09:28 PM   #10
jordanpetruska
Member
 
jordanpetruska's Avatar
 
Join Date: 06-11-10
Location: Kent City, MI
Posts: 46
iTrader: (1)
Mentioned: 0 Post(s)
Default

one of my buddies did this alittle bit ago. alittle higher compression. the porting and polishing is pretty easy to do yourself. we just did the head on my jeep motor just for the hell of it. im sure it wont make a damn bit of difference, but we did it anyway.
jordanpetruska is offline   Reply With Quote
Old January 13th, 2012, 09:33 PM   #11
chadcooper55
expert jeep disassembler
 
chadcooper55's Avatar
 
Join Date: 08-28-08
Location: kent city mi
Posts: 8,026
iTrader: (20)
Mentioned: 9 Post(s)
Default

Quote:
Originally Posted by jordanpetruska View Post
one of my buddies did this alittle bit ago. alittle higher compression. the porting and polishing is pretty easy to do yourself. we just did the head on my jeep motor just for the hell of it. im sure it wont make a damn bit of difference, but we did it anyway.
I'll have to talk to your buddy before I do it jordan. Did you get you jeep running good yet?
__________________
I hate being bipolar, its great!

jeep turned buggy now back to jeep
http://www.greatlakes4x4.com/showthread.php?t=175584
chadcooper55 is offline   Reply With Quote
Old January 14th, 2012, 06:59 AM   #12
ScOoTeR
hoo dat. wat.
 
ScOoTeR's Avatar
 
Join Date: 11-09-05
Location: Howell
Posts: 21,394
iTrader: (35)
Mentioned: 6 Post(s)
Default

Chad, if you want - I can show you how to build a DIY flowbench and give you a few caveats on port shaping. Many heads benefit from material being *added* in addition to removed.
__________________
@clarkstoncracker
ScOoTeR is online now   Reply With Quote
Old January 14th, 2012, 09:29 AM   #13
chadcooper55
expert jeep disassembler
 
chadcooper55's Avatar
 
Join Date: 08-28-08
Location: kent city mi
Posts: 8,026
iTrader: (20)
Mentioned: 9 Post(s)
Default

Quote:
Originally Posted by ScOoTeR View Post
Chad, if you want - I can show you how to build a DIY flowbench and give you a few caveats on port shaping. Many heads benefit from material being *added* in addition to removed.
That would be awesome scooter! I would really appreciate it. I really want to learn how to do it correctly.
__________________
I hate being bipolar, its great!

jeep turned buggy now back to jeep
http://www.greatlakes4x4.com/showthread.php?t=175584
chadcooper55 is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT -5. The time now is 10:50 PM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Copyright 2005 - 2012 Cracker Enterprises - Powered by Linux
vB Ad Management by =RedTyger=
Page generated in 0.15035 seconds with 38 queries