049 oval versus zz502 #390 oval heads - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 10-07-2004, 10:54 PM
Member
 

Last journal entry: pro systems carb
Last photo:
Join Date: Jun 2004
Location: StThomas Ont
Posts: 51
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
049 oval versus zz502 #390 oval heads

Ok Im seeing a trend everywhere to switch from rec port heads to oval ports. I have a crate ls6 and saw an ad for 049 heads for 100 bucks, I'm not sure what it would cost to have these heads rebuilt to hot rod specs (can funds) but I noticed the gm aluminum #390's will cost me about 2000.00 Can. funds by the time they get to the great white north, so I'm looking for direction, can the 049's make great power without breaking the 2k dollar mark ? will they outflow the 390's with a port and polish? or are the new heads superior no matter what is done to the 049's because of the passage of time and technology? Thanks for the keystrokes

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 10-08-2004, 12:16 AM
Member
 
Join Date: Apr 2004
Location: carmichael, CA
Age: 39
Posts: 91
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
don`t know the flow rates of the aluminum heads but they must be pretty good if GM is using them on their performance motors. The 049 heads are very good. You can install the bigger valves, do a little bowl work and gasket match and they will be great performing heads. I don`t think the 049 would out flow the alunimun heads, at least not without some professional porting with a flow bench. I could be wrong though since I`m not familyar with the aluminum heads.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-08-2004, 11:31 AM
firestone's Avatar
http://teamrfc.gospelcom.net
 
Last photo:
Join Date: Nov 2003
Location: Fenton MI
Age: 32
Posts: 1,743
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
I know of two cars where I live that have 468's with ported 049's. Both of the cars are pump gas. One is a late 70's malibu with a solid roller cam, and 10.5:1 compression. It is an all steel car with a full interior and it runs 10.80 in the 1/4. The other guy has not yet taken the car to the track, but he has a hydraulic roller with around 9.5:1 compression and his motor dynoed at 550 hp and 550 tq. My point is that 049's are good heads. I am not sure how much you are going to spend on a good port/bigger valve job, but I would think you could do it for under $2000. As far as flow goes, if you did up the 049's they would probably outflow the unported GMPP aluminum heads, but the big deal is that they would have a smaller runner which mean that you would have much higher port velocity which makes more hp and torque, that is why so many people with motors in the 454-477 range are going with oval port heads. If you have a 500+ cubic inch motor, I would recommend the GMPP heads just because of the size of the motor. Although if you have an extra $1000 to spend over the GMPP heads, and you are building a 496 or something, you can get a set of 315cc CNC ported AFR heads for $3000 and be looking at 700 hp with a really streetable pump gas combonation.

Adam

Here is a site where you can compare the stock small valve 049's to a set of GMPP heads. The GMPP heasd win here, but notice how the 049's keep up with the GMPP heads in the mid lift area. this is very important for hp. You can imagine what would happen if you put a set of 2.19 1.88 valves in the 049's and gave them a little port job.

http://chevyhiperformance.com/techar...98/index8.html

Good luck
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 10-08-2004, 12:21 PM
Member
 

Last journal entry: pro systems carb
Last photo:
Join Date: Jun 2004
Location: StThomas Ont
Posts: 51
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks firestone, thats all I needed to make up my mind. Right now I have an extreme energy hyd cam in the stock bore 454 its about 240/246 @50 and 550 - 575 lift the motor is about 10.5 to one , not sure but I have good cyl. pressure (about 185 to 200 across the board), my 55 chevy has a 10inch -4000 convertor , ladder/bar c/o's rear , 373 gears . 325/50 drag radials, 3.5 inch mufflers/ex , the car has only gone 112 mph with ported ls6 heads, (too little cam ,too much head, not enough cubes, I'm guessing), so I will save the heads for a 540 in the future, and go with and air gap intake and 850 holley , and get the 049s upgraded with valves and a port job, then cam? solid this time but what size I'm not sure
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 10-08-2004, 01:50 PM
firestone's Avatar
http://teamrfc.gospelcom.net
 
Last photo:
Join Date: Nov 2003
Location: Fenton MI
Age: 32
Posts: 1,743
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
I am building almost the exact same motor, and I am going with the XR280R (242 248 @.050 .646 .653 lift). It seemed just about perfect to me with a 2500-6500 RPM band.

Adam
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 10-08-2004, 04:57 PM
Member
 

Last journal entry: pro systems carb
Last photo:
Join Date: Jun 2004
Location: StThomas Ont
Posts: 51
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Hmmm, one thing I dont have a clue about is if my "popup" dome style ls6 pistons will be ok with the 049 heads, any answers guys
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 10-08-2004, 06:02 PM
Member
 
Join Date: Apr 2004
Location: carmichael, CA
Age: 39
Posts: 91
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
You can run closed chamber pistons with open chamber heads but you`ll lose about 1 point of compression. You should also check all clearances. Head to piston, piston to valve, ect.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 10-14-2004, 05:51 PM
Member
 

Last journal entry: pro systems carb
Last photo:
Join Date: Jun 2004
Location: StThomas Ont
Posts: 51
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
hmmm. both the 188 ls6 head and the 049 oval port heads are open chamber, what conflicts will I run into with my ls6 pistons ? I thought that the guidelines would be to look out for closed chamber heads on a motor that came with open chamber ? Isn't the valve to piston clearance the next priority? I'm a little confused wouldnt my pistons be open chamber compatible. Next question is how much would a typical "performance rebuild " be for these heads (049 ovals) this would be comparible to the bolt on heads of the zz502, so valves, pocket port, guides, springs, ect.. all the accesories that come with the 502 ovals , are these heads in the same "ballpark" as the 502 heads after they come back from the typical machine shop? Thanks
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 10-16-2004, 12:40 PM
Member
 

Last journal entry: pro systems carb
Last photo:
Join Date: Jun 2004
Location: StThomas Ont
Posts: 51
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Anybody use the Dart iron eagle BBC 308 heads?
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 06:36 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.