Cylinder Heads - What Matters Most?
#122
TECH Senior Member
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
WOW. Seventeen posts and only one or two breaks from others. And NOTHING but pure rambling DRIVEL! What a waste in such an otherwise great thread.
Smokey, how about FOCUSING FOR ONCE and combining your seventeen posts into one or two? Unless looking to get banned AGAIN is your aim....
You are another reason I have NO room for dopers in my life.
Smokey, how about FOCUSING FOR ONCE and combining your seventeen posts into one or two? Unless looking to get banned AGAIN is your aim....
You are another reason I have NO room for dopers in my life.
#125
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
My personal, real world experience,
When I bought my TMS 370, I opted for the CNC 317s they offered for $750. Static CR was 10.75:1.
Motor went in, tuned it and it ran good.
I felt it could run better.
So I started reading, a lot. I kept reading about port velocity vs port volume and I started wondering if those 23x CNC heads were hindering me?
So I swapped the CNC heads for plain ole 706s, knowing I was going to have to pull the timing back some.
I retuned it and holy damn what a difference. My CR IS about 12.0:1 but it was retuned and I pulled some timing back.
While I was retuning it, I also noticed that it wanted about 10-13% less fuel in the VE table. That’s right, less fuel. But why? Tighter quench? It’s more efficient now?
It’s a night/day difference in a daily driver. If I were boosted it’d be different I’m sure.
For me, port velocity in an everyday NA driver.
(FYI, I am not bashing TMS)
When I bought my TMS 370, I opted for the CNC 317s they offered for $750. Static CR was 10.75:1.
Motor went in, tuned it and it ran good.
I felt it could run better.
So I started reading, a lot. I kept reading about port velocity vs port volume and I started wondering if those 23x CNC heads were hindering me?
So I swapped the CNC heads for plain ole 706s, knowing I was going to have to pull the timing back some.
I retuned it and holy damn what a difference. My CR IS about 12.0:1 but it was retuned and I pulled some timing back.
While I was retuning it, I also noticed that it wanted about 10-13% less fuel in the VE table. That’s right, less fuel. But why? Tighter quench? It’s more efficient now?
It’s a night/day difference in a daily driver. If I were boosted it’d be different I’m sure.
For me, port velocity in an everyday NA driver.
(FYI, I am not bashing TMS)
#126
TECH Senior Member
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
You gained some efficiency via the increased compression, but the increased velocity certainly did not hurt things either.
Now everyone is gonna want to put 706's on their builds! lol
Now everyone is gonna want to put 706's on their builds! lol
#127
TECH Veteran
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Richard Holdener got a test called.... 706 vs the the world. The 706 heads held they own.
#128
TECH Senior Member
iTrader: (4)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
My personal, real world experience,
When I bought my TMS 370, I opted for the CNC 317s they offered for $750. Static CR was 10.75:1.
Motor went in, tuned it and it ran good.
I felt it could run better.
So I started reading, a lot. I kept reading about port velocity vs port volume and I started wondering if those 23x CNC heads were hindering me?
So I swapped the CNC heads for plain ole 706s, knowing I was going to have to pull the timing back some.
I retuned it and holy damn what a difference. My CR IS about 12.0:1 but it was retuned and I pulled some timing back.
While I was retuning it, I also noticed that it wanted about 10-13% less fuel in the VE table. That’s right, less fuel. But why? Tighter quench? It’s more efficient now?
It’s a night/day difference in a daily driver. If I were boosted it’d be different I’m sure.
For me, port velocity in an everyday NA driver.
(FYI, I am not bashing TMS)
When I bought my TMS 370, I opted for the CNC 317s they offered for $750. Static CR was 10.75:1.
Motor went in, tuned it and it ran good.
I felt it could run better.
So I started reading, a lot. I kept reading about port velocity vs port volume and I started wondering if those 23x CNC heads were hindering me?
So I swapped the CNC heads for plain ole 706s, knowing I was going to have to pull the timing back some.
I retuned it and holy damn what a difference. My CR IS about 12.0:1 but it was retuned and I pulled some timing back.
While I was retuning it, I also noticed that it wanted about 10-13% less fuel in the VE table. That’s right, less fuel. But why? Tighter quench? It’s more efficient now?
It’s a night/day difference in a daily driver. If I were boosted it’d be different I’m sure.
For me, port velocity in an everyday NA driver.
(FYI, I am not bashing TMS)
With 706's, more efficient with 12 to 1 compression, better velocity, u definitely believe the engine woke up, more responsive etc.
Back in ~2001-2002 ported 706's were an excellent set up, I guess fears of the "Castec Cracking" issue and inexpensive 243/799's made the 706 less popular over time.
Last edited by 99 Black Bird T/A; 05-28-2019 at 08:47 PM.
#129
ModSquad
iTrader: (6)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
WOW. Seventeen posts and only one or two breaks from others. And NOTHING but pure rambling DRIVEL! What a waste in such an otherwise great thread.
Smokey, how about FOCUSING FOR ONCE and combining your seventeen posts into one or two? Unless looking to get banned AGAIN is your aim....
You are another reason I have NO room for dopers in my life.
Smokey, how about FOCUSING FOR ONCE and combining your seventeen posts into one or two? Unless looking to get banned AGAIN is your aim....
You are another reason I have NO room for dopers in my life.
I have absolutely no idea was he’s trying to say here, and usually I can somewhat decipher a little bit of the lingo. Need a translator in here, STAT!
#131
TECH Addict
iTrader: (3)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
His crap is annoying and really annoying. Im new to alot of this technical stuff. I was following this thread and even rereading it a few times. Great discussions, than he shows up n ruins it. Can someone please ban his dumb ***, at least from posting anything that isnt in plain english??? Im serious, it never gets better and clutters up GOOD threads, it brings nothing to the table but headaches. It reminds me of yellow bullet and why im over here more than there.
#133
LS1Tech Premium Sponsor
iTrader: (2)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I think you saw the most difference from the compression ratio and MAYBE the smaller port but more likely that 23x port just had poor design.
Youd likely have better luck with those heads cncd on like a tsp 2.5 program where they are still in the 22x port but have much better flow or an aftermarket casting.
Normally i only like 23xcc for 408 or larger or for 5k+ builds. The 220-227 are better for 4.030 or smaller and stock stroke especially on skreet stuff. Smaller chambers also up to a point.
I haven't heard much good from anything tms either.
Youd likely have better luck with those heads cncd on like a tsp 2.5 program where they are still in the 22x port but have much better flow or an aftermarket casting.
Normally i only like 23xcc for 408 or larger or for 5k+ builds. The 220-227 are better for 4.030 or smaller and stock stroke especially on skreet stuff. Smaller chambers also up to a point.
I haven't heard much good from anything tms either.
#134
Super Hulk Smash
iTrader: (7)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
My personal, real world experience,
When I bought my TMS 370, I opted for the CNC 317s they offered for $750. Static CR was 10.75:1.
Motor went in, tuned it and it ran good.
I felt it could run better.
So I started reading, a lot. I kept reading about port velocity vs port volume and I started wondering if those 23x CNC heads were hindering me?
So I swapped the CNC heads for plain ole 706s, knowing I was going to have to pull the timing back some.
I retuned it and holy damn what a difference. My CR IS about 12.0:1 but it was retuned and I pulled some timing back.
While I was retuning it, I also noticed that it wanted about 10-13% less fuel in the VE table. That’s right, less fuel. But why? Tighter quench? It’s more efficient now?
It’s a night/day difference in a daily driver. If I were boosted it’d be different I’m sure.
For me, port velocity in an everyday NA driver.
(FYI, I am not bashing TMS)
When I bought my TMS 370, I opted for the CNC 317s they offered for $750. Static CR was 10.75:1.
Motor went in, tuned it and it ran good.
I felt it could run better.
So I started reading, a lot. I kept reading about port velocity vs port volume and I started wondering if those 23x CNC heads were hindering me?
So I swapped the CNC heads for plain ole 706s, knowing I was going to have to pull the timing back some.
I retuned it and holy damn what a difference. My CR IS about 12.0:1 but it was retuned and I pulled some timing back.
While I was retuning it, I also noticed that it wanted about 10-13% less fuel in the VE table. That’s right, less fuel. But why? Tighter quench? It’s more efficient now?
It’s a night/day difference in a daily driver. If I were boosted it’d be different I’m sure.
For me, port velocity in an everyday NA driver.
(FYI, I am not bashing TMS)
#136
Moderator
Thread Starter
iTrader: (4)
Join Date: Jul 2014
Location: My own internal universe
Posts: 10,452
Received 1,852 Likes
on
1,152 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
My gut tells me 706 heads are too small for your build. But 23x was too big. Agree with tech and others on that.
Imo a decent raised 220 cc port and a good valve size like a 2.05 would be about right for that 370.
Personally I like 317 heads for boost but not NA. Basically big chamber 243 heads. By the time you mill down the valves are way close. Good head for boost but not my favorite NA.
Rather than porting the 317s could just slap on some ls3 heads honestly.
Imo a decent raised 220 cc port and a good valve size like a 2.05 would be about right for that 370.
Personally I like 317 heads for boost but not NA. Basically big chamber 243 heads. By the time you mill down the valves are way close. Good head for boost but not my favorite NA.
Rather than porting the 317s could just slap on some ls3 heads honestly.
#137
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Smokey needs to go to rehab for a while and cleanse his system.
The rambling really distracts me from focusing on all the other useful information here.
I do not understand how he can be bothered doing what he does.
Anyway, compression ratio is another interesting topic.
Say you have an LS7 with a large camshaft with 25 degrees of overlap.
If you have the stock compression vs 13:1 for example would there be any power gains if you were using e85 for both?
Would your fuel efficiency also better with the higher compression?
I know engines run hotter with more compression too.
The rambling really distracts me from focusing on all the other useful information here.
I do not understand how he can be bothered doing what he does.
Anyway, compression ratio is another interesting topic.
Say you have an LS7 with a large camshaft with 25 degrees of overlap.
If you have the stock compression vs 13:1 for example would there be any power gains if you were using e85 for both?
Would your fuel efficiency also better with the higher compression?
I know engines run hotter with more compression too.
#138
TECH Addict
iTrader: (3)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Is it safe to assume most of you tune your own cars too? I like the knowledge on here, its just crazy how much opinions can vary in different aspects of the build. I had a hard time pickn who to use for a tq converter. Seemd like Circle D and FTI had different opinions for my set up. Yet both are well respected vendors in the game...and thats just tq converters