Question about 4v B-Heads - MustangForums.com


4.6L (1996-2004 Modular) Mustang Technical discussions on 1996-2004 4.6 Liter Modular Motors (2V and 4V) within.

Reply
 
 
 
Thread Tools Search this Thread
Old 06-02-2011, 09:07 AM   #1
98SN95
2nd Gear Member
Thread Starter
 
Join Date: Nov 2007
Location: New Orleans, LA
Posts: 362
Default Question about 4v B-Heads

I am trying to get everything together to do a 4v swap, i have a compltete 93 mark 8 motor, i have purchased a 98 cobra intake, but now im hearing things about the valve springs, can i put 98 cobra beehive valve springs on 93 mark 8 heads, and if so whats involved?
98SN95 is offline   Reply With Quote
Old 06-02-2011, 10:15 AM   #2
Bmitchell373
2nd Gear Member
 
Bmitchell373's Avatar
 
Join Date: Sep 2010
Location: Phoenix, AZ
Posts: 395
Default

Should be a direct cross over.
Bmitchell373 is offline   Reply With Quote
Old 06-02-2011, 11:06 AM   #3
sn95_331_GT_ yellow
5th Gear Member
 
sn95_331_GT_ yellow's Avatar
 
Join Date: Mar 2008
Location: CT
Posts: 2,394
Default

shouldnt make a difference theyre all B heads, they didnt go to the C heads until '99
sn95_331_GT_ yellow is offline   Reply With Quote
Old 06-02-2011, 11:17 AM   #4
SVTeeshirt
5th Gear Member
 
Join Date: Nov 2007
Location: Maryland
Posts: 4,950
Default

they are the same heads.... cams may be different not 100%.
SVTeeshirt is offline   Reply With Quote
Old 06-02-2011, 12:52 PM   #5
BlackMage
5th Gear Member
 
BlackMage's Avatar
 
Join Date: Oct 2003
Location: Northern Wisconsin
Posts: 2,010
Default

cams are the same from 93-98 in the Mark VIII's.. the only difference is in the 96-98 cobra the intake camshaft was different, and is the ones u want. the rest of the camshafts from other 4v motors i wouldn't even bother with.
BlackMage is offline   Reply With Quote
Old 06-02-2011, 08:04 PM   #6
98SN95
2nd Gear Member
Thread Starter
 
Join Date: Nov 2007
Location: New Orleans, LA
Posts: 362
Default

I read a post from another site that said the valve stem seals were different, I confirmed this with Ford, but I'm wondering if as long as I change seals and valves I'll be OK, if anyone knows anyone who has done this first hand please ask if I'm right
98SN95 is offline   Reply With Quote
Old 06-03-2011, 03:34 PM   #7
nickmckinney
3rd Gear Member
 
nickmckinney's Avatar
 
Join Date: Jan 2009
Location: Florida
Posts: 570
Default

Quote:
Originally Posted by SVTeeshirt View Post
they are the same heads.... cams may be different not 100%.


They are NOT the same heads. The 93-95 B heads have a swirl dam in the combustion chamber between the 2 intake valves. The intake flow is much lower if left stock.

The valve seals are different as the guide tops are different.

You will need to swap both the springs and retainers from a 96 or newer set of heads. All 4V heads other than the 5.4 Cobra/Shelby used the same parts.

To be completely honest, its a very disappointing swap. A stock PI motor with cams will make the same HP with a ton more torque. Early B heads are the same as later once ported, but stock they leave a lot to be desired. If you are intent on a 4V swap then get a set of 03 or newer heads with a Mach intake (its better than the 99-01 cobra intake) and a set of 96-98 Cobra cams. Thats worth about 50RWHP over the Mark motor.
nickmckinney is offline   Reply With Quote
Old 06-03-2011, 06:03 PM   #8
JC316
4th Gear Member
 
JC316's Avatar
 
Join Date: May 2009
Location: DFW, TX
Posts: 1,925
Default

Quote:
Originally Posted by nickmckinney View Post
They are NOT the same heads. The 93-95 B heads have a swirl dam in the combustion chamber between the 2 intake valves. The intake flow is much lower if left stock.

The valve seals are different as the guide tops are different.

You will need to swap both the springs and retainers from a 96 or newer set of heads. All 4V heads other than the 5.4 Cobra/Shelby used the same parts.

To be completely honest, its a very disappointing swap. A stock PI motor with cams will make the same HP with a ton more torque. Early B heads are the same as later once ported, but stock they leave a lot to be desired. If you are intent on a 4V swap then get a set of 03 or newer heads with a Mach intake (its better than the 99-01 cobra intake) and a set of 96-98 Cobra cams. Thats worth about 50RWHP over the Mark motor.
He is right about the heads, they are just slightly different. Not sure how much it actually impedes the flow of air, especially since the 93 Mark VIII is known to be the strongest from the factory.

Now, the stock PI/cammed motor, I am not so sure about. I had a Mark VIII swapped 96 GT and a bolt on, pi swapped 98 GT.

The 96 was bone stock down to the exhaust. The 98 had LT headers, ORH, flows, 3.73's, UDP's, and a CAI. The 96 absolutely smoked the 98.
JC316 is offline   Reply With Quote
Old 06-03-2011, 08:50 PM   #9
nickmckinney
3rd Gear Member
 
nickmckinney's Avatar
 
Join Date: Jan 2009
Location: Florida
Posts: 570
Default

The 93-95 Mark intake manifold makes more power than the 96-98 Mark intake, but it won't fit in a Mustang. Trust me on the cammed PI 2V smoking a stock Mark B motor, been there done that (and I probably own more B heads than anyone else on the planet)

BTW - working up a set of early B heads right now for 8500RPM and 35lbs of boost on straight alcohol. Heads got Timeserts on all 8 cylinders, Manley beadlock valves, and a set of $700 valve springs to handle the abuse.

Last edited by nickmckinney; 06-03-2011 at 08:54 PM.
nickmckinney is offline   Reply With Quote
Old 06-03-2011, 10:45 PM   #10
98SN95
2nd Gear Member
Thread Starter
 
Join Date: Nov 2007
Location: New Orleans, LA
Posts: 362
Default

I already have purchased a 98 Cobra intake, got the heads back from the machine shop today, now I need to get a valvetrain together
98SN95 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Beheading the B-head crysalis_01 SVT Forums 21 07-01-2011 06:45 PM
Looking to line out a build plan crysalis_01 SVT Forums 5 04-15-2011 07:20 PM
B headed S/Sers come in!!!! silverstang1996 Street/Strip 10 09-23-2008 01:29 AM
IMRCs? B-heads? 97snakebite SVT Forums 5 03-04-2008 09:49 PM


Tags
4v, 95, beehive, cobra, heads, install, long, mark, modular, mustang, spring, springs, strongest, swap, valve, viii

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump


All times are GMT -5. The time now is 10:14 AM.