T7 head on B204 - The Saab Link Forums

Go Back   The Saab Link Forums > Saab NG900 '94-'98 and 9-3 '99-'02 Forum > Performance Modifications for the NG900 / Old 9-3

Performance Modifications for the NG900 / Old 9-3 This forum contains PERFORMANCE related Q&A's for the NG900 and 9-3. This may also include suspension.

SaabLink.net is the premier Saab Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools
Old 02-29-2008, 08:05 PM   #1
Elder
 
Castor Troy's Avatar
 
Join Date: Nov 2003
Location: Montana
Posts: 3,998
T7 head on B204

My uncle has a spare top end from a 9-5, and after seeing the 16v head flow data, i definitely want to put it on my NG900. I know the exhaust manifolds are the same, but will I have to use the T7 intake manifold on the 900? Is that going to make doing a mailbox tune a nightmare?

another question. i'm gonna start building my new bottom end soon. i have JE pistons; what should i gap the rings to?
__________________
^The preceeding post probably had something to do with Seth Romer.

Last edited by Castor Troy; 02-29-2008 at 08:12 PM.
Castor Troy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 03-01-2008, 04:30 AM   #2
Live, eat, and sleep by TSL
 
Join Date: May 2004
Posts: 1,122
Quote:
Originally Posted by Castor Troy View Post
My uncle has a spare top end from a 9-5, and after seeing the 16v head flow data, i definitely want to put it on my NG900. I know the exhaust manifolds are the same, but will I have to use the T7 intake manifold on the 900? Is that going to make doing a mailbox tune a nightmare?

another question. i'm gonna start building my new bottom end soon. i have JE pistons; what should i gap the rings to?

In case you have missed, your NG900 is already with a 16v head and the difference in flow is not that big between the T5 and T7 head.

But if you wish to mount it anyways, the T7 intake manifold with create problems because the connection to TB is diffent as well as fuel rail mounts and some other nipples. Other option is just to use the T5 inlet manifold thus its port is smaller than the T7's heads, but it works. Other recommended option is to mount the T7 manifold flange to you existing T5, ie. cut and weld.
Vigge is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 03-01-2008, 06:21 AM   #3
Elder
 
amish_geek's Avatar
 
Join Date: Sep 2006
Location: Yumping a Swedish Model
Posts: 4,098
Send a message via AIM to amish_geek Send a message via MSN to amish_geek
The gains in flow between a T7 head and a T5 head are also due to the narrower(weaker) valve stems IIRC. So what you gain in flow, you lose in durability.


IMO, you're better off keeping the T5 head with the beefier valves, and make up for the "poorer" flow with a bigger turbo and more boost.
__________________
DVNO, Four Capital Letters, Written in Gold
amish_geek is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
 
Old 03-01-2008, 07:10 AM   #4
Live, eat, and sleep by TSL
 
Join Date: May 2004
Posts: 1,122
Quote:
Originally Posted by amish_geek View Post
The gains in flow between a T7 head and a T5 head are also due to the narrower(weaker) valve stems IIRC. So what you gain in flow, you lose in durability.


IMO, you're better off keeping the T5 head with the beefier valves, and make up for the "poorer" flow with a bigger turbo and more boost.
Nope it is not just the valves, the ports differ among the two heads. Intake side flow more or less the same, but T7 exhaust side dramatically more (difference in desing principle)
Also the material of the T7 valve is "better" than the T5 so its durability does not scale in direct portion to the diameter. However the springs are with less force in T7 and couple other pieces making it a "poorer" choice if the aim is to rev high etc.
Vigge is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 03-01-2008, 10:20 AM   #5
JZW
Elder
 
Join Date: Oct 2006
Location: Boulder Colorado
Posts: 3,153
Quote:
Originally Posted by Castor Troy View Post
My uncle has a spare top end from a 9-5, and after seeing the 16v head flow data, i definitely want to put it on my NG900. I know the exhaust manifolds are the same, but will I have to use the T7 intake manifold on the 900? Is that going to make doing a mailbox tune a nightmare?

another question. i'm gonna start building my new bottom end soon. i have JE pistons; what should i gap the rings to?

The top compression ring end gap should be set in accordance to the amount of power you plane to make and how you make that power. Turbo vs nitrous and so on.

On my je pistons the minimum distance was .015", no matter what. For high hp and turbo charged, it was around .017" to .021" and for nitrous and circle track racing, constant high reving, it was more like .023-.024".

The end gap is important and there should be a spec sheet with you're pistons that tell you the ballpark range for each hp and power adder set-up.

Having said all that, I set my 450bhp set-up to .018" and Eric set his to .021" and the wider the ring gap, the more blow-bye of oil you will get if you are not making the pressure and power you were setting it up to handle.

On the head, t7 vs t5, many people go back to the t5 head for racing and high hp motors because the larger valve stem size is more durable. There have been quite a few cases of t7 valves bending under extreme racing conditions. Maptun recommends a t5 head for their stage7 470bhp set-up.

If you wanted to run the t7 head, I would put in the t5 valves and then port/polish the t5 intake manifold to make it as close as possible to the t7 intake port, ie port match! Then flow the exhaust side and spend the most time in the bowls and the short radi side.

Good Luck,

John
__________________
b234r ng900, E-85 Holset Super [email protected] mph a mile high 645whp/650wtrq Sae Denver
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
JZW is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-28-2008, 04:38 AM   #6
Elder
 
NickTurbo900's Avatar
 
Join Date: Sep 2005
Location: Greater Burlington, Vermont
Posts: 4,023
This is a great thread! As I'm mating up my B234 to the T7 head for the 9-5 motor I was wondering if there was any difference whatsoever between the T5 heads of a B204L and the B234R/L, the 900 vs the 9k... They appear to my eyes to be identical. TIA.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
NickTurbo900 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-28-2008, 05:41 AM   #7
Nick Taliaferro
Elder
 
GenuineSaab's Avatar
 
Join Date: Feb 2004
Location: Springfield, MO USA
Posts: 3,232
Send a message via MSN to GenuineSaab Send a message via Skype™ to GenuineSaab
I have been running 7000 to 7200 rev limit on the stock head on my Vig.. Some of that with bigger cams.. Not a big worry for me since most saabs do not make power up that high anyway.

I saw light gains switching the B234 head with a Bx5 head on the NA car.. Most of that was from gaining a little compression by using the B2x5 thin head gasket.
__________________
Nicholas Taliaferro

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
|
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
|
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

2.0 GOOSE 500whp + 8500rpm = 11.06 @125 E85
Viggen 439whp / 447tq 12.43 @114 on Gt2871.64, (Now 511whp Gt3076)
Nordic E85 9-3 SS Aero 320hp / 350ftlbs
GenuineSaab is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-28-2008, 07:10 AM   #8
JZW
Elder
 
Join Date: Oct 2006
Location: Boulder Colorado
Posts: 3,153
Quote:
Originally Posted by Castor Troy View Post
My uncle has a spare top end from a 9-5, and after seeing the 16v head flow data, i definitely want to put it on my NG900. I know the exhaust manifolds are the same, but will I have to use the T7 intake manifold on the 900? Is that going to make doing a mailbox tune a nightmare?

another question. i'm gonna start building my new bottom end soon. i have JE pistons; what should i gap the rings to?

I know someone that just had the t5 head flow tested against the t7 head and there was absolutely no difference in flow

John
__________________
b234r ng900, E-85 Holset Super [email protected] mph a mile high 645whp/650wtrq Sae Denver
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
JZW is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-28-2008, 07:12 AM   #9
JZW
Elder
 
Join Date: Oct 2006
Location: Boulder Colorado
Posts: 3,153
Quote:
Originally Posted by Vigge View Post
In case you have missed, your NG900 is already with a 16v head and the difference in flow is not that big between the T5 and T7 head.

But if you wish to mount it anyways, the T7 intake manifold with create problems because the connection to TB is diffent as well as fuel rail mounts and some other nipples. Other option is just to use the T5 inlet manifold thus its port is smaller than the T7's heads, but it works. Other recommended option is to mount the T7 manifold flange to you existing T5, ie. cut and weld.
Wondering where you have received you're information? I know a person that just had the t7 head flow tested against the t5 head and they saw no difference in flow at all.....

John
__________________
b234r ng900, E-85 Holset Super [email protected] mph a mile high 645whp/650wtrq Sae Denver
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
JZW is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 05-29-2008, 01:30 AM   #10
Live, eat, and sleep by TSL
 
Join Date: May 2004
Posts: 1,122
Quote:
Originally Posted by JZW View Post
Wondering where you have received you're information? I know a person that just had the t7 head flow tested against the t5 head and they saw no difference in flow at all.....

John
Can you post both the intake and exhaust flow results for different valve lifts?
I base my commnets on the flow bench results I have, and note that I have stated a few times that the intake sides flow more or less the same.
Vigge is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 06-01-2008, 01:04 AM   #11
JZW
Elder
 
Join Date: Oct 2006
Location: Boulder Colorado
Posts: 3,153
I am hoping that information is available. We shall see. I was also told there seems to be two styles of t7 heads. One that has the same style intake ports as the t5 head, but has the smaller t7 valves and weaker valve springs.

Then there is the "other" t7 head, like on the viggen with taller intake side and the smaller t7 valve stems. You would think with that head and the t7 intake, there would be better flow.

I am now wondering which t7 head was flow tested against the t5 head, the one that is almost the same or the one with taller intake.

John
__________________
b234r ng900, E-85 Holset Super [email protected] mph a mile high 645whp/650wtrq Sae Denver
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
JZW is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the The Saab Link Forums forums, you must first register.
Please enter your desired user 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:
Vehicle Info.
Enter your vehicle information (year, model, mods)
Insurance
Please select your insurance company (Optional)

Log-in


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 -8. The time now is 04:57 AM.


Powered by vBulletin® Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Friendly URLs by vBSEO 3.5.2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
All content is copyright The Saab Link and it's original authors.


 

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.