Welcome to Modern Mopar Forum

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more! This message will be removed once you have signed in.

Sign in to follow this  
Followers 0
Teddyp

Difference In Valve Size?

Anybody know the size difference in the valves between stock Apache heads and the HEMI Big Gas Heads? Also the flow numbers between the two?

 

 

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

I think there the same size and flow, The big gas truck head is made out of better aluminum (356)and have harder valve seats, and sodium filled valves.

Share this post


Link to post
Share on other sites

Not to say your not-but a reliable source told me the big gas heads have larger valves, along with other improvements, which you already pointed out. I figured IF the valves are larger then it must flow more than the Apaches. I've scoured the forums, Internet, and manufactures-short of making phone calls-I don't want to waste their valuable time, trying to find out what the numbers are, and I can't find anything. Just wondering, IF they are bigger, by how much.

 

 

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

Not to say your not-but a reliable source told me the big gas heads have larger valves, along with other improvements, which you already pointed out. I figured IF the valves are larger then it must flow more than the Apaches. I've scoured the forums, Internet, and manufactures-short of making phone calls-I don't want to waste their valuable time, trying to find out what the numbers are, and I can't find anything. Just wondering, IF they are bigger, by how much.

 

 

Sent from my iPhone using Tapatalk

Nope, same size 2.14 (54.3mm) and 1.65 (42.mm). Have a pair sitting right here. There a better choice for boosted applications IMO. 

Share this post


Link to post
Share on other sites

Nope, same size 2.14 (54.3mm) and 1.65 (42.mm). Have a pair sitting right here. There a better choice for boosted applications IMO.

Thank you. That being said, they come from Modern Muscle with the heads ported, multi angle cuts on the valves, and the seats blended. That would have to increase the head flow, correct??

 

 

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

The same, stock and ported.

i don't understand, if ones ported, and ones not, they flow the same? Can you elaborate and teach me something? Post #6 I thought you said they flowed more, (Big gas heads)? I'm confused.

 

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

i don't understand, if ones ported, and ones not, they flow the same? Can you elaborate and teach me something? Post #6 I thought you said they flowed more, (Big gas heads)? I'm confused.

 

Sent from my iPhone using Tapatalk

The port shape and geometry are the same as Apache. Stock for stock, they flow the same. You can run the same CNC program through both heads so they will flow the same in a ported form as well. If you have a ported Big gas head, it will outflow a non ported head, either big gas or Apache.

 

As for what they flow, ask your shop who did the porting. They will be able to tell you. Not all ported heads flow the same.

Share this post


Link to post
Share on other sites

The port shape and geometry are the same as Apache. Stock for stock, they flow the same. You can run the same CNC program through both heads so they will flow the same in a ported form as well. If you have a ported Big gas head, it will outflow a non ported head, either big gas or Apache.

 

As for what they flow, ask your shop who did the porting. They will be able to tell you. Not all ported heads flow the same.

Gotcha. Thanks for the explanation.

 

 

Sent from my iPhone using Tapatalk

Share this post


Link to post
Share on other sites

i wanna bump this.  as ive got biggas heads as well.  they are smoother casting stock for stock umported vs apachies.  biggas outflow the apachies in unported numbers by 15-25cfm@.600lift.   265>245 respectively.   

i have heard somebody say they reach 420@.600 lift ported.  i want proof or i call bs.  

i also want to know and will see if they need the same opening up behind the valve seat like the rest of the gen3 heads that gives 20-30+cfm by a valve job.<<---- anyone know this answer?

Share this post


Link to post
Share on other sites

well i have gotten my answer.   YES. there is 30cfm left inside the valve seat by getting a cheap valve job on these heads across the board.  fyi for all you who didnt know but would like to know or looking to find out.  this type of work shohld be cheap and under 250 bucks to get done and can be done fairly easily by anybody that van do a standard valve job.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0