#1  
Old 03-09-2021, 10:50 PM
PAUL K's Avatar
PAUL K PAUL K is online now
Ultimate Warrior
 
Join Date: Feb 2004
Location: Sugar Grove IL USA
Posts: 6,283
Default Speedmaster cylinder heads

While waiting for a return phone call today I realized I had a pair of 72cc Edelbrock heads and Speedmasters waiting in line for some work. I studied them a bit side by side and thought I'd share a few observations.

Intake ports are CNC matched from both manufacturers. The Edelbrock in the first picture is blended and smoothed with a sanding roll. The second picture is the Speedmaster which is not blended or smoothed and leaves some large ridges which will have a negative effect on performance.

The exhaust ports on the Edelbrocks are CNC matched (to a specific size) and the Speedmasters are as cast.
Attached Thumbnails
Click image for larger version

Name:	20210309_150657_HDR.jpg
Views:	829
Size:	47.5 KB
ID:	562377   Click image for larger version

Name:	20210309_150708_HDR.jpg
Views:	870
Size:	38.3 KB
ID:	562378   Click image for larger version

Name:	20210309_150927_HDR.jpg
Views:	795
Size:	42.6 KB
ID:	562379   Click image for larger version

Name:	20210309_150939_HDR.jpg
Views:	736
Size:	38.9 KB
ID:	562380  

__________________
Go fast, see Elvis!
www.facebook.com/PaulKnippensMuscleMotors
The Following 4 Users Say Thank You to PAUL K For This Useful Post:
  #2  
Old 03-09-2021, 10:55 PM
PAUL K's Avatar
PAUL K PAUL K is online now
Ultimate Warrior
 
Join Date: Feb 2004
Location: Sugar Grove IL USA
Posts: 6,283
Default

Both chambers are CNC machined and point the spark plug towards the exhaust valve. The Edelbrock chamber un-shrouds the plug and smooths out any exposed plug threads in the chamber.

Edelbrock head is on the right
Attached Thumbnails
Click image for larger version

Name:	20210309_160323.jpg
Views:	786
Size:	48.8 KB
ID:	562381   Click image for larger version

Name:	20210309_160223.jpg
Views:	791
Size:	40.3 KB
ID:	562382  

__________________
Go fast, see Elvis!
www.facebook.com/PaulKnippensMuscleMotors

Last edited by PAUL K; 03-09-2021 at 11:32 PM.
The Following User Says Thank You to PAUL K For This Useful Post:
  #3  
Old 03-09-2021, 11:02 PM
PAUL K's Avatar
PAUL K PAUL K is online now
Ultimate Warrior
 
Join Date: Feb 2004
Location: Sugar Grove IL USA
Posts: 6,283
Default

The Speedmaster head's valve job was cut using a radius cutter on the intake and exhaust seats. The Edelbrock uses your basic multi-angle cutter on both.

The Edelbrock has the bowls blended and smoothed. The Speedmasters are not and they have sharp edges that need to be smoothed or some of their performance potential will be negatively affected.

The Edelbrock head is on the left.
Attached Thumbnails
Click image for larger version

Name:	20210309_150724.jpg
Views:	758
Size:	58.4 KB
ID:	562383   Click image for larger version

Name:	20210309_150906_HDR.jpg
Views:	730
Size:	51.7 KB
ID:	562384  

__________________
Go fast, see Elvis!
www.facebook.com/PaulKnippensMuscleMotors

Last edited by PAUL K; 03-09-2021 at 11:39 PM.
The Following User Says Thank You to PAUL K For This Useful Post:
  #4  
Old 03-09-2021, 11:21 PM
PAUL K's Avatar
PAUL K PAUL K is online now
Ultimate Warrior
 
Join Date: Feb 2004
Location: Sugar Grove IL USA
Posts: 6,283
Default

This picture has the SM valve on the left and Edelbrock on the right. The dye shows where the valve seat is located in relation the the valve face. Both intake seats had good placement. The exhaust seat on the E was good but for some reason the exhaust seat on the SM is located at the bottom of the face (closer to the valve stem).
Attached Thumbnails
Click image for larger version

Name:	20210309_203528.jpg
Views:	624
Size:	51.8 KB
ID:	562387  

__________________
Go fast, see Elvis!
www.facebook.com/PaulKnippensMuscleMotors

Last edited by PAUL K; 03-09-2021 at 11:46 PM.
The Following 2 Users Say Thank You to PAUL K For This Useful Post:
  #5  
Old 03-09-2021, 11:25 PM
PAUL K's Avatar
PAUL K PAUL K is online now
Ultimate Warrior
 
Join Date: Feb 2004
Location: Sugar Grove IL USA
Posts: 6,283
Default

This picture shows an area of concern with the SM head. The intake bowl in this area is approximately .050 smaller that the valve insert. This is the area if you start chasing big power and open up the bowl it may cause the seat insert to fall out. It also causes an issue with shaping the bowl in relation to the valve job.
Attached Thumbnails
Click image for larger version

Name:	20210309_160103.jpg
Views:	678
Size:	42.0 KB
ID:	562388  

__________________
Go fast, see Elvis!
www.facebook.com/PaulKnippensMuscleMotors
The Following User Says Thank You to PAUL K For This Useful Post:
  #6  
Old 03-09-2021, 11:30 PM
PAUL K's Avatar
PAUL K PAUL K is online now
Ultimate Warrior
 
Join Date: Feb 2004
Location: Sugar Grove IL USA
Posts: 6,283
Default

FWIW

__________________
Go fast, see Elvis!
www.facebook.com/PaulKnippensMuscleMotors
  #7  
Old 03-09-2021, 11:55 PM
ID67goat's Avatar
ID67goat ID67goat is offline
Senior Chief
 
Join Date: Nov 2007
Posts: 411
Default

Paul,

Good info, thanks for sharing!

With as side by side comparison, it clearly looks like the Edelbrock head is more refined than the SpeedMaster based on your pictures..

Please keep us posted on any other findings as you set these heads up.

  #8  
Old 03-10-2021, 12:43 AM
Dragncar Dragncar is offline
Ultimate Warrior
 
Join Date: Mar 2004
Location: Humbolt County California
Posts: 8,284
Default

Well, if there is not enough materiel under that seat to prevent them from falling out if one chooses to for big power, welding required.
Thats not good.
Those Gabby E heads I have, under the area under the seat opened up is huge.
The SM heads need some finish work. Those tests done by their manufacturer showing they flowed a bit more than the E heads, was that intake port blended ? You would think it had to be to outflow the E head.

  #9  
Old 03-10-2021, 05:51 AM
Murf Murf is offline
Ultimate Warrior
 
Join Date: Aug 2000
Location: St. Marys Ks. U.S.A.
Posts: 1,486
Default

Quote:
Originally Posted by PAUL K View Post
While waiting for a return phone call today I realized I had a pair of 72cc Edelbrock heads and Speedmasters waiting in line for some work. I studied them a bit side by side and thought I'd share a few observations.



Intake ports are CNC matched from both manufacturers. The Edelbrock in the first picture is blended and smoothed with a sanding roll. The second picture is the Speedmaster which is not blended or smoothed and leaves some large ridges which will have a negative effect on performance.



The exhaust ports on the Edelbrocks are CNC matched (to a specific size) and the Speedmasters are as cast.


Paul, first off thanks for posting this!

Are the Edelbrock’s intakes roll sanded from the factory or had you already work on them?

Do you have any plans to compare the flow of these heads?

Thanks
Murf


Sent from my iPhone using Tapatalk Pro

  #10  
Old 03-10-2021, 06:43 AM
RUDOLFSSON's Avatar
RUDOLFSSON RUDOLFSSON is offline
Chief Ponti-yacker
 
Join Date: Mar 2002
Location: Kopavogur, Iceland
Posts: 990
Default

Thanks for posting.... glad I bought the originals ;-)

__________________
*** THE BIG BRACE is here ***
The Following User Says Thank You to RUDOLFSSON For This Useful Post:
  #11  
Old 03-10-2021, 08:41 AM
grivera's Avatar
grivera grivera is offline
Ultimate Warrior
 
Join Date: Feb 2005
Location: Just south of Baltimore
Posts: 4,891
Default

Thanks for posing Paul - always nice to get first hand accounts of relatively new products.

Quote:
Originally Posted by Murf View Post
Paul, first off thanks for posting this!

Are the Edelbrock’s intakes roll sanded from the factory or had you already work on them?

Do you have any plans to compare the flow of these heads?

Thanks
Murf


Sent from my iPhone using Tapatalk Pro

Murf - I assume you've seen Randy's (Goatzilla) thread on the SM heads and comparison to E-Heads

https://forums.maxperformanceinc.com...0&postcount=16


That being said it would be nice to see another test.

__________________
Will Rivera

'69 Firebird 400/461, 290+ E D-Ports, HR 230/236, 4l80E, 8.5 Rear, 3.55 gears
'64 LeMans 400/461, #16 Heads, HR 230/236, TKO600, 9inch Rear, 3.89 gears
'69 LeMans Vert, 350, #47 heads: Non-running project
The Following User Says Thank You to grivera For This Useful Post:
  #12  
Old 03-10-2021, 10:03 AM
pontbil pontbil is offline
Senior Member
 
Join Date: Aug 2004
Location: Maryland
Posts: 109
Default

The first set of E heads I purchased when they first came out were great here is a pic of the new ones I bought last year when they went on sale and and was very disappointed
Attached Thumbnails
Click image for larger version

Name:	e head.JPG
Views:	603
Size:	86.3 KB
ID:	562404  

  #13  
Old 03-10-2021, 10:21 AM
P@blo's Avatar
P@blo P@blo is offline
Ultimate Warrior
 
Join Date: Aug 2005
Location: Manitoba
Posts: 1,519
Default

Thanks Paul for sharing. I was very close to picking these SM up on sale last November but realized it was only the price that was attractive. Glad I didn't and that was before you posted your thread.

So much for the SpeedMaster being the same as the Edelbrock and wonder if the advertised flow is on an as-sold head.

The Following User Says Thank You to P@blo For This Useful Post:
  #14  
Old 03-10-2021, 11:08 AM
Region Warrior's Avatar
Region Warrior Region Warrior is offline
Ultimate Warrior
 
Join Date: Apr 2004
Location: NW Indiana
Posts: 6,544
Default

Got a set of E-heads 2nd year they 1st came out. Where boxed as cast. Looked perfect everywhere.

__________________
If you cant drive from gas pump to gas pump across the map, its not a street car.


http://s207.photobucket.com/albums/b...hop/?start=100
  #15  
Old 03-10-2021, 11:25 AM
1968GTO421's Avatar
1968GTO421 1968GTO421 is offline
Ultimate Warrior
 
Join Date: May 2014
Location: Travelers Rest, SC
Posts: 1,285
Default

Thanks Paul for posting the info and pics. Food for thought. Reminds you that you get what you pay for.

__________________


"No replacement for displacement!"

GTOAA--https://www.gtoaa.org/
The Following User Says Thank You to 1968GTO421 For This Useful Post:
  #16  
Old 03-10-2021, 12:03 PM
grivera's Avatar
grivera grivera is offline
Ultimate Warrior
 
Join Date: Feb 2005
Location: Just south of Baltimore
Posts: 4,891
Default

Quote:
Originally Posted by P@blo View Post
Thanks Paul for sharing. I was very close to picking these SM up on sale last November but realized it was only the price that was attractive. Glad I didn't and that was before you posted your thread.

So much for the SpeedMaster being the same as the Edelbrock and wonder if the advertised flow is on an as-sold head.
Goatzilla flowed both heads as cast:

https://forums.maxperformanceinc.com...0&postcount=16

__________________
Will Rivera

'69 Firebird 400/461, 290+ E D-Ports, HR 230/236, 4l80E, 8.5 Rear, 3.55 gears
'64 LeMans 400/461, #16 Heads, HR 230/236, TKO600, 9inch Rear, 3.89 gears
'69 LeMans Vert, 350, #47 heads: Non-running project
  #17  
Old 03-10-2021, 12:33 PM
rohrt rohrt is offline
Ultimate Warrior
 
Join Date: May 2004
Location: Cedar Rapids, IA
Posts: 4,125
Default

Paul,

I don't see anything that is a deal breaker there for me. Not that I'm shopping for heads or anything. But If I did I guess I would do some blending of the bowls. Seem like a couple hours of work to save $1200. However looking at the flow numbers it may not even be all that necessary.

How significant is the exhaust seat alignment and the intake seat placement?

  #18  
Old 03-10-2021, 12:35 PM
napster's Avatar
napster napster is offline
Chief Ponti-yacker
 
Join Date: Sep 2005
Posts: 719
Default

Paul K,

Thanks for posting this information. This will help in making decisions since it seems it is getting harder to get Edelbrock heads. Seems some things will need to be done on the Speedmaster heads to take them up to standards we would all want. Nice to know there is an alternative.

Thanks,

Jim

The Following User Says Thank You to napster For This Useful Post:
  #19  
Old 03-10-2021, 01:11 PM
P@blo's Avatar
P@blo P@blo is offline
Ultimate Warrior
 
Join Date: Aug 2005
Location: Manitoba
Posts: 1,519
Default

Quote:
Originally Posted by grivera View Post
Goatzilla flowed both heads as cast:

https://forums.maxperformanceinc.com...0&postcount=16
Oh okay thanks Will. I wouldn't expect a chinaman communist head head to be as nice as something made in the USA. Like mentioned we get what we pay for and the SM customer service sucks to top it.

Too bad the aftermarket cast iron heads never happened.

  #20  
Old 03-10-2021, 01:56 PM
78w72 78w72 is offline
Ultimate Warrior
 
Join Date: Nov 2007
Location: iowa
Posts: 4,683
Default

Quote:
Originally Posted by rohrt View Post
Paul,

I don't see anything that is a deal breaker there for me. Not that I'm shopping for heads or anything. But If I did I guess I would do some blending of the bowls. Seem like a couple hours of work to save $1200. However looking at the flow numbers it may not even be all that necessary.

How significant is the exhaust seat alignment and the intake seat placement?
where are you seeing $1200 difference? summit shows the speedmasters are like $1900/pr assembled, E-heads are $1069ea, 2140/pr assembled, they are both 72cc round port heads. or am i missing something on that $1200??

The Following User Says Thank You to 78w72 For This Useful Post:
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Forum Jump


All times are GMT -4. The time now is 09:13 AM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017