what height do you set your gt40 valve springs to - Ford Mustang Forums : Corral.net Mustang Forum
Go Back   Ford Mustang Forums : Corral.net Mustang Forum > Windsor Tech Forums > 5.0/5.8 Engine Tech

Corral.net is the premier Ford Mustang Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
Old 09-11-2011, 03:02 PM   #1
Registered User

Trader Feedback: (0)
 
Join Date: Apr 2011
Location: San Diego
Posts: 24

Lightbulb what height do you set your gt40 valve springs to

So I have gt40 heads and new valve spring kit from Alex Parts that I want to install. I have been reading a lot about install height, coil bind, and all sort.

I have stock cam with 1.72 rockers so my lift will be around .477

The springs install height @ 1.78 is 120lbs
----------------coil bind @ 1.100
----------------max lift @ .600

So if I install it at 1.78 with my .477 lift I will have .203 before coil bind...

I have the hardened shim kit so am I going to want to bring the install height down to 1.7-1.71 to be closer to .130 before coil bind

or

bring the intall height down more to be closer to .60 range... I have read multiple posts and threads and each one says something different so I would like to get an opinion on here.

I plan on going turbo with these heads in the future so I want to get this right the first time.
dirty2003 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 09-12-2011, 07:49 AM   #2
Registered User

Trader Feedback: (20)
 
Join Date: Nov 2008
Location: BOONDOCKS
Posts: 876

worry more about open and closed pressures, when you get the proper closed pressure on the seat then what ever intalled height it took to get that, so be it...and it may fall within what spec says, but you must check that and have proper stuff to do such, after that coil bind can be checked ,ect ect , knowing the cam to be used is important as well.
85gt66 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 09-12-2011, 09:34 AM   #3
Registered User

Trader Feedback: (13)
 
Join Date: Apr 2003
Location: Utah
Posts: 4,822

what is spring rate.
__________________
2001 Notch 281
Heads, Cam, Intake
Goody_Seven 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 09-13-2011, 01:25 PM   #4
Registered User

Trader Feedback: (0)
 
Join Date: Apr 2011
Location: San Diego
Posts: 24

Its a 120lbs at 1.78" for the seat pressure.
dirty2003 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 09-13-2011, 01:40 PM   #5
Registered User

Trader Feedback: (3)
 
Join Date: Jul 2006
Location: Montana
Posts: 706

Quote:
Originally Posted by dirty2003 View Post
Its a 120lbs at 1.78" for the seat pressure.
Spring rate?
bender4601 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 09-13-2011, 10:21 PM   #6
Registered User

Trader Feedback: (0)
 
Join Date: Apr 2011
Location: San Diego
Posts: 24

sorry about that here are all the specs i have for the springs.

Spring Specifications:

•1.460" Outside Diameter

•.980" Inside Diameter

•120 Lbs @ 1.780" Valve Closed Installed Height

•280 Lbs @ .500" Lift
•310 Lbs @ .600" Lift
•No spring seat machining required
dirty2003 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 09-14-2011, 09:39 AM   #7
Registered User

Trader Feedback: (3)
 
Join Date: Jul 2006
Location: Montana
Posts: 706

Here is what I would do.. Some one please check my math....

coil bind-----1.100
Lift----------0.477
clearance----0.123
----------------------
Installed height 1.700

At 1.700 145lbs (seat)

At 1.223 297lbs (at lift)

320lb rate.
bender4601 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 09-15-2011, 11:56 PM   #8
Registered User

Trader Feedback: (0)
 
Join Date: Apr 2011
Location: San Diego
Posts: 24

Bump.... that sounds about right. Anybody else have some input
dirty2003 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 09-16-2011, 05:10 AM   #9
Registered User
 
tripleblackvert's Avatar

Trader Feedback: (74)
 
Join Date: Jul 2008
Location: mountaintop,pa
Posts: 5,250

You dead set on those springs? The open rates on those Alex springs looks pretty weak, considering stock springs are at 230lbs open..i think the stock rate is like 315lbs/in if my math is correct...i wouldnt run those...i would run from those...

ive been using:
Crane 44308-1
adv. specs:
118Lbs @ 1.950
Coil bind- 1.320"
Open- 375lbs @ 1.380"
457 lb/in rate

Install @ 1.880" will put you .083" from coil bind
~150 on the seat and ~370 at lift
__________________
1987 Notch - N/A stock 302, TFS heads, Holley Systemax, FTI cam, Astro A5
Best so far: 10.92 @ 123mph with a 1.49 60ft

Last edited by tripleblackvert; 09-16-2011 at 08:13 AM.
tripleblackvert 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

Bookmarks

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Mustang Forums : Corral.net Mustang Forum 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:

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.



Thread Tools
Display Modes

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 -4. The time now is 01:31 AM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Friendly URLs by vBSEO 3.5.2
© 2010-2011 Corral.net

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.