Installed Height - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



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

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 06-12-2019, 07:06 AM
Excellenceautosoluti's Avatar
Registered User
 
Last photo:
Join Date: Nov 2016
Location: Pinehurst North Carolina
Posts: 109
Wiki Edits: 0

Thanks: 59
Thanked 14 Times in 14 Posts
Installed Height

Hello fellas. I've got a silly question. As this is my first time setting up heads, I need a little help. I've searched around on the subject, and found each Cam Company will have requirements for spring seat pressure and installed height.
My question is, do i have to pick a cam before I build these heads with the kit from Competition Products?
https://www.competitionproducts.com/...6/#.XFoCH3dFy7

The specs for these springs at 1.75 is 130 pounds.

The root of the question being, how do cylinder heads get set up before being sold to be able to run a specific type of cam? I.E. Hydraulic Roller, Flat Tappet ETC... without knowing exactly what cam will be used in a particular customers engine?

BTW, I know I will have a Hydraulic Roller in the 280ish adv. and .550ish zone.
And the castings are these. .
https://www.ebay.com/itm/2-x-Aluminu....c100903.m5276
Thanks in advance for all your help. And yes I do have the bronze guides soaking in some oil right now as per excellent direction from Tech or Bogie, can't remember which one. But you BOTH are awesome. And thanks Eric for walking me through my purchasing process.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 06-12-2019, 07:51 AM
johnsongrass1's Avatar
Race it, Don't rice it!
 
Last photo:
Join Date: Jul 2002
Location: Columbia, Mo
Age: 42
Posts: 6,798
Wiki Edits: 0

Thanks: 96
Thanked 655 Times in 538 Posts
All pre-assembled heads are set up for typical generic rates. It's why buying pre-assembled heads are worth going through. I've yet too see them ready to go out of the box. Usually its the guides are tight or the springs aren't ideal.
When ever humans are involved they have bad days too and things are built on Mondays and Fridays so it's always worth checking.

Pick the heads first, so you can pick a cam that compliments them.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 06-12-2019, 08:32 AM
Registered User
 
Last photo:
Join Date: Apr 2007
Posts: 12,070
Wiki Edits: 0

Thanks: 150
Thanked 1,025 Times in 816 Posts
Quote:
Originally Posted by Excellenceautosoluti View Post
Hello fellas. I've got a silly question. As this is my first time setting up heads, I need a little help. I've searched around on the subject, and found each Cam Company will have requirements for spring seat pressure and installed height.
My question is, do i have to pick a cam before I build these heads with the kit from Competition Products?
https://www.competitionproducts.com/...6/#.XFoCH3dFy7

The specs for these springs at 1.75 is 130 pounds.

The root of the question being, how do cylinder heads get set up before being sold to be able to run a specific type of cam? I.E. Hydraulic Roller, Flat Tappet ETC... without knowing exactly what cam will be used in a particular customers engine?

BTW, I know I will have a Hydraulic Roller in the 280ish adv. and .550ish zone.
And the castings are these. .
https://www.ebay.com/itm/2-x-Aluminu....c100903.m5276
Thanks in advance for all your help. And yes I do have the bronze guides soaking in some oil right now as per excellent direction from Tech or Bogie, can't remember which one. But you BOTH are awesome. And thanks Eric for walking me through my purchasing process.
The problem is the head manufacturer puts in a generic spring to cover a range of likely cam selections. It may or not be right for the cam you pick. This is a big endorsement for buying heads bare; then purshasing valves, retainers, lock, and seals seperatly from a reliable source. An example is Competition Products who has developed head completion kits at several quality levels or you can buy the individual pieces essentially putting together your own 'kit' the way you want it.

As for springs, unless you are knowledgeable on the subject of matching springs to cams, I highly recommend sticking with the cam manufacturer's recommendation. They have tested the recommended spring and know how it reacts with a typical valve train part selection and their lobe profile. Especially today with flat tappet cam wear this is important to avoid simply having too much spring pressure for the job but having enough to do the job of controlling the valve assembly with incurring undo wear on the tappet and lobe.

Stepping out on my own spring selection a common set up I had used for cams that support a 400 to 420 hp output for a street 350 as an example I used the Howards electro-polished beehive with good result, mind you this is not a recommendation for any cam. It worked well on flat tappet cams in the range you would see with the Comp XE268H flat tappet or the GMPP LT4HOT roller tappet cam. This covered heads with GM factory valve sizes of 1.94x1.5 inch through aftermarket 2.05x1.6 inch; using steel retainers , usually with Comp's 787 and standard 7 degree locks, with positive stem seals.

With aftermarket heads you need to know the needed valve stem length, many heads require a valve with an additional .1 (sometimes .2) inch of additional stem length, you also need to be aware of differences in heights of bare stem above the lock grooves as there are some variables out there when you step into aftermarket valves. Basically for stem length what has happened is the head manufacturer raised the spring deck height for manufacturing reasons so the spring pocket in relation to the valve seat sits higher, this dictates a longer stem so that standard length dimension springs can be used. Aside from the longer stem the rest of the valve assembly uses standard parts. This can change when you move into serious racing heads and parts so you can't get complacent about dimensions and their effects on parts. Keep in mind, especially with beehives, that these are often wound for metric dimension valves so the GM factory retainer is sized for an 8 mm valve stem where the common aftermarket valve stem and SBC production through the L31 Vortec use an 11/32 stem. Metric and US sizes do not interchange around the 8mm to 11/32nds stems, so you must be aware when shopping for these parts whether you look at standard barrel shaped springs, beehives, or conical springs you have got to get the info whether it is in the fine print or by calling their techhelp line. This is a good place for dumb questions so as to avoid wasting money on parts that dont fit together or having an operating failure from this cause.

Bogie

Last edited by BogiesAnnex1; 06-12-2019 at 08:41 AM.
Reply With Quote Quick reply to this message
 
  #4 (permalink)  
Old 06-12-2019, 09:03 AM
Excellenceautosoluti's Avatar
Registered User
 
Last photo:
Join Date: Nov 2016
Location: Pinehurst North Carolina
Posts: 109
Wiki Edits: 0

Thanks: 59
Thanked 14 Times in 14 Posts
Thanks for the speedy replies.
Just to be clear, I have already purchased and am building a set of heads. I have purchased the above kit from Competition Products and the pair of bare heads this cylinder head upgrade kit is going in.
This kit supplies the necessary hardware for Hydraulic Roller setup with the proper valves and all components already together.

I am wondering what do I set the installed height at for the springs?

Sorry for the confusing question.

Thanks again.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 06-12-2019, 09:04 AM
Registered User
 
Join Date: Jun 2010
Location: TX
Posts: 3,739
Wiki Edits: 0

Thanks: 36
Thanked 426 Times in 397 Posts
Today, aftermarket high performance flat tappet camshafts should be wlimited to less than 110 lb. seat pressure and 290 lb open pressure due to no lead gasoline and oil.

Roller tappet camshafts are required for seat pressures over 125 lb. The risky area is between 110 lb and 125 lb seat pressure and more than 290 lb. open pressure.

If you have valve seat pressure over 110 lb. and more than 290 lb open pressure, use those springs and a flat tappet camshaft at your own risk and pay particular attention to a proper break in.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 06-12-2019, 09:25 AM
Registered User
 
Last photo:
Join Date: Jan 2018
Location: Laurel, De.
Posts: 354
Wiki Edits: 0

Thanks: 197
Thanked 149 Times in 111 Posts
Quote:
Originally Posted by Excellenceautosoluti View Post
Thanks for the speedy replies.
Just to be clear, I have already purchased and am building a set of heads. I have purchased the above kit from Competition Products and the pair of bare heads this cylinder head upgrade kit is going in.
This kit supplies the necessary hardware for Hydraulic Roller setup with the proper valves and all components already together.

I am wondering what do I set the installed height at for the springs?

Sorry for the confusing question.

Thanks again.
Use the specs that the manufacture provides for the springs. Too much height and you have less then the listed pressures. Too little height and you have to much pressure or can run into coil bind. Spring shims and/or + or - locks can get you dialed in. If you're using self aligning rockers, tip protrusion above the retainer is important. I use a hardened shim under the spring to prevent galling of the seat pocket or a spring cup if the springs are smaller diameter than the machined pocket.There's usually plenty of room on aftermarket heads but I still verify retainer to guide clearance taking into account the height of the seal. Some spring makers list .030 as a figure to stay away from coil bind. I like to see more and .050 or more on the guide to retainer clearance.

Last edited by Hipster_G; 06-12-2019 at 09:42 AM.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 06-12-2019, 09:26 AM
Registered User
 
Join Date: Jun 2010
Location: TX
Posts: 3,739
Wiki Edits: 0

Thanks: 36
Thanked 426 Times in 397 Posts
I am using the GM “068” (Z-28 and stock V8) valve springs set up with 80 lb seat pressure and 280 lb open pressure using a GM “151” hydraulic lifter camshaft with .447” valve lift. That set up in a 1968 350 CI SB Chevrolet engine in my 1962 Bel Air has more than 65, 000 miles on it and I can shift at 5,000 to 5,200 RPM with 4.11:1 positraction, 29” rear tires, without any valve float and power loss.

Factory GM camshafts have lobes with slow acceleration ramps which will extend the life of their camshafts in daily drivers. The factory GM camshafts will last well beyond the 50,000 mile drive line warranty.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 06-12-2019, 01:29 PM
Excellenceautosoluti's Avatar
Registered User
 
Last photo:
Join Date: Nov 2016
Location: Pinehurst North Carolina
Posts: 109
Wiki Edits: 0

Thanks: 59
Thanked 14 Times in 14 Posts
1.7500000 in case anyone was wondering...
It helps to call the source. Thanks to all who participated.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 06-12-2019, 02:01 PM
2001Blazer4x4's Avatar
Redneck Professional
 
Last photo:
Join Date: Jan 2015
Location: Indiana
Posts: 771
Wiki Edits: 0

Thanks: 97
Thanked 165 Times in 140 Posts
Quote:
Originally Posted by Excellenceautosoluti View Post
1.7500000 in case anyone was wondering...
It helps to call the source. Thanks to all who participated.
Getcha one of these! https://www.jegs.com/i/Proform/778/66902/10002/-1
Reply With Quote Quick reply to this message
The Following User Says Thank You to 2001Blazer4x4 For This Useful Post:
Excellenceautosoluti (06-12-2019)
  #10 (permalink)  
Old 06-12-2019, 02:35 PM
Excellenceautosoluti's Avatar
Registered User
 
Last photo:
Join Date: Nov 2016
Location: Pinehurst North Carolina
Posts: 109
Wiki Edits: 0

Thanks: 59
Thanked 14 Times in 14 Posts
Got one. I pretty much have everything I need for the heads already. Just had one question, but Competition Products answered it in about 45 seconds. I'm excited about this build, picking up a block next week to send out and get started on.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 06-12-2019, 02:48 PM
2001Blazer4x4's Avatar
Redneck Professional
 
Last photo:
Join Date: Jan 2015
Location: Indiana
Posts: 771
Wiki Edits: 0

Thanks: 97
Thanked 165 Times in 140 Posts
Quote:
Originally Posted by Excellenceautosoluti View Post
Got one. I pretty much have everything I need for the heads already. Just had one question, but Competition Products answered it in about 45 seconds. I'm excited about this build, picking up a block next week to send out and get started on.
good luck and have a good time building it. I've always thought that learning to build the engine yourself was one of the things to be proud of. Anyone with money can buy one.
Reply With Quote Quick reply to this message
The Following 2 Users Say Thank You to 2001Blazer4x4 For This Useful Post:
55 Tony (06-12-2019), Excellenceautosoluti (06-12-2019)
  #12 (permalink)  
Old 06-12-2019, 04:55 PM
55 Tony's Avatar
Registered User
 
Join Date: Nov 2018
Location: Cocke County, TN
Posts: 882
Wiki Edits: 0

Thanks: 120
Thanked 136 Times in 119 Posts
Quote:
Originally Posted by 2001Blazer4x4 View Post
good luck and have a good time building it. I've always thought that learning to build the engine yourself was one of the things to be proud of. Anyone with money can buy one.

I agree. Built mine a few years ago with help on the internet and help on the phone. Just today it rolled over 10,000 miles. Still working on it though, put new heads on and trying to get the most out of them.


Not to say that there is anything wrong with someone who lacks the know how or urge to do it, just saying that it makes me feel proud to know I did it, and it's still running!
__________________
Young enough to learn ... too old to remember.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 06-12-2019, 07:22 PM
Registered User
 
Last photo:
Join Date: Apr 2007
Posts: 12,070
Wiki Edits: 0

Thanks: 150
Thanked 1,025 Times in 816 Posts
Quote:
Originally Posted by Excellenceautosoluti View Post
Thanks for the speedy replies.
Just to be clear, I have already purchased and am building a set of heads. I have purchased the above kit from Competition Products and the pair of bare heads this cylinder head upgrade kit is going in.
This kit supplies the necessary hardware for Hydraulic Roller setup with the proper valves and all components already together.

I am wondering what do I set the installed height at for the springs?

Sorry for the confusing question.

Thanks again.
If an aluminum head there must be a spacer, often referred to as a spring cup, placed between the head and spring otherwise the steel spring will chew up the aluminum. Since o the extent that springs are somewhat generic in lenght considering head material, the installed spring length on an aluminum head will be less than the same spring installed to an iron head. This will affect pressure the aluminum head seeing more than the iron head.

Chewing up the installed spring's length this way adds to the need to check coil bind.

The cam manufacturer specified a spring in terms of force per unit measure of length. For a performance engine his needs to be tested for every spring i.e. installed length and open valve length for each spring then those found short of specification need to be replaced or "shimmed". I put shimmed in quotes as there are a couple ways to do this. The most common is with shims under the spring (which you essentially have do do this for an aluminum head in order to protect the head, if aluminum that's your starting point period) the other method is to use off set locks which move the groove step up or down be some dimension generally .050 inch from its nominal position. This raises or lowers the spring retainer thus lengthing or shortening the springs installed height which affects its installed pressure.

This is a problem that gets even more complex once the head is subject to a valve job, double so when not done on a Serdi machine which is set up to cut all the head seats to a common depth so at least with new valves the stems project the same height above the spring seats.

This is the knd of stuff where your money goes when building a performance engine

If you're looking for a simple answer that would be 'put it together and hope for the best'. I'm not recommending that, but a lot of guys do it.

Bogie
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 06-13-2019, 06:35 AM
Excellenceautosoluti's Avatar
Registered User
 
Last photo:
Join Date: Nov 2016
Location: Pinehurst North Carolina
Posts: 109
Wiki Edits: 0

Thanks: 59
Thanked 14 Times in 14 Posts
Thanks again guys.
I'm grateful for this site. Here is where I have gleaned the information to have the courage to go for my second build. The first motor I built was 2 years ago and it is still going strong. This one will have a little more twist to it.
If I had been more informed on my last one I would have done it differently. Last one was started with an L31 Vortec from a 99 model truck. I had the heads upgraded to beehive springs, and surfaced to make flat. We decked the block .02. But HERE is where I went wrong... I wanted to keep it a budget build and kept all stock internals with only a hone and new rings, and bearings. Now this motor does just fine, 13.9 @96. But I missed out on the benefits a 383 with forged internals would have given my 4000 pound truck. 4020 with me in it.
This time around we have the good foreign bare head castings and a Competition Products head improvement kit [as stated in the very first post here] find links above. I'm happy this combination of parts has come highly recommended from several members on this site, and I'm confident there will be no shots in the dark here. I'm sure there will be more questions as I go through this process, and I know with all of Y'alls help around here I can make this happen.
You can follow my build thread here. https://www.hotrodders.com/forum/638-block-521539.html
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:
Insurance
Please select your insurance company (Optional)

Log-in



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 01:35 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.