|
MP Hemi head porting, HP improvement?
#2682841
07/30/19 08:14 PM
07/30/19 08:14 PM
|
Joined: Mar 2010
Posts: 984
Tennessee
Hemi ragtop
OP
super stock
|
OP
super stock
Joined: Mar 2010
Posts: 984
Tennessee
|
I have a 540 I HEMI, 4.360” bore, 4.5” stroke. It is a street car, 4,100 lb. 3.54 gear with GV. The cam is 248/254 @ .050 with .580 net lift solid roller 112 lobe separation. 10.5 CR.
cruising rpm is 2,500-3,000.
How much power will a good street port make on a MP aluminum head? the engine made 635 HP @ 5,900 rpm, Teardown revealed horrible bore finish, no way the rings were sealing. Along with other issues. All is fixed, I am keeping the cam etc. Just clean up of the valve pocket of the head, and port match.
I don’t feel the need for the Victor head, I am not after max power. But while we are at it, the heads are getting a “street” port job.
What is your experience?
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: Hemi ragtop]
#2682862
07/30/19 09:06 PM
07/30/19 09:06 PM
|
Joined: Jan 2003
Posts: 11,991
Benton, IL.
DaveRS23
Special needs idiot
|
Special needs idiot
Joined: Jan 2003
Posts: 11,991
Benton, IL.
|
MCH ported my MP Eddy heads several years ago. My engine specs are very similar to yours. I broke my engine in on the local speed shop engine dyno. So here's my combo; 540" Hemi, 10.25cr +/-, 250* sft cam, .565 .547 lift, 2 1/4" headers, Indy single plane intake, and Thumper's 1050 Dominator. Made 697hp @ 6,800 and was pulling vacuum. The single plane made 11 more hp at the top, but lost 30+ lbs of torque through the range to the Indy dual plane back-to-back. So, I am running the dual plane in the car. 70 Cuda, primarily street car, 518od, 4,000 converter, 3.91 gears, 3,850lbs with me and gas. Have made a few passes at the local 1/8 mile track on a test and tune night. Not enough runs to dial it all in and with plenty of spinning, it ran 1.68 60', 7.16 @ 98.5. Clearly high 6s and 100+ is within easy reach with a little suspension tuning and a little practice. ![[Linked Image]](https://i73.photobucket.com/albums/i225/DaveRS23/2017-10-19%2012.43.48_zpsslj7wpfg.jpg) ![[Linked Image]](https://i73.photobucket.com/albums/i225/DaveRS23/2017-10-19%2012.44.05_zpsbkbrjyiv.jpg)
Master, again and still
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: Hemi ragtop]
#2682896
07/30/19 10:07 PM
07/30/19 10:07 PM
|
Joined: May 2004
Posts: 12,383
Taxes & Virus's R-US, NY
Dragula
I Live Here
|
I Live Here
Joined: May 2004
Posts: 12,383
Taxes & Virus's R-US, NY
|
Hemi heads, for a mild engine flow pretty good. Out of the box MP heads usually flow around 375cfm which is more than my EZ1 Indy wedge heads.....Should be able to make over 700hp with them....
Your cam is holding you back more than anything......Port matching helps, what intake and carb?
Last edited by Dragula; 07/30/19 10:13 PM.
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: Dragula]
#2682908
07/30/19 10:21 PM
07/30/19 10:21 PM
|
Joined: Mar 2011
Posts: 3,066
Michigan
A727Tflite
master
|
master
Joined: Mar 2011
Posts: 3,066
Michigan
|
Hemi heads, for a mild engine flow pretty good. Out of the box MP heads usually flow around 375cfm which is more than my EZ1 Indy wedge heads.....Should be able to make over 700hp with them....
Your cam is holding you back more than anything......Port matching helps, what intake and carb? Which head flows this much? WIth the large intake valve or the 2.25” intake ?
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: A727Tflite]
#2682911
07/30/19 10:27 PM
07/30/19 10:27 PM
|
Joined: May 2004
Posts: 12,383
Taxes & Virus's R-US, NY
Dragula
I Live Here
|
I Live Here
Joined: May 2004
Posts: 12,383
Taxes & Virus's R-US, NY
|
Hemi heads, for a mild engine flow pretty good. Out of the box MP heads usually flow around 375cfm which is more than my EZ1 Indy wedge heads.....Should be able to make over 700hp with them....
Your cam is holding you back more than anything......Port matching helps, what intake and carb? Which head flows this much? WIth the large intake valve or the 2.25” intake ? MP 2.25 valve heads should be in that range. My Canfield 2.4 valve heads flow 458cfm....For the money the Eddy heads are pretty good too.....
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: Dragula]
#2682963
07/31/19 05:41 AM
07/31/19 05:41 AM
|
Joined: Mar 2010
Posts: 984
Tennessee
Hemi ragtop
OP
super stock
|
OP
super stock
Joined: Mar 2010
Posts: 984
Tennessee
|
Hemi heads, for a mild engine flow pretty good. Out of the box MP heads usually flow around 375cfm which is more than my EZ1 Indy wedge heads.....Should be able to make over 700hp with them....
Your cam is holding you back more than anything......Port matching helps, what intake and carb? I am running an MP “marine” dual carb dual plane with two 750 Hollies
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: Hemi ragtop]
#2682994
07/31/19 09:22 AM
07/31/19 09:22 AM
|
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
|
Out of the box MP heads usually flow around 375cfm Uuuuhhhh........... not even close.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: fast68plymouth]
#2682998
07/31/19 09:35 AM
07/31/19 09:35 AM
|
Joined: Jan 2003
Posts: 13,345
Marion, South Carolina [><]
an8sec70cuda
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 13,345
Marion, South Carolina [><]
|
Out of the box MP heads usually flow around 375cfm Uuuuhhhh........... not even close. I thought they were more in the 330 cfm range? MCH cnc ported my MP heads back in 2006 and they flow right at 430 cfm.
CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: fast68plymouth]
#2683003
07/31/19 09:44 AM
07/31/19 09:44 AM
|
Joined: May 2004
Posts: 12,383
Taxes & Virus's R-US, NY
Dragula
I Live Here
|
I Live Here
Joined: May 2004
Posts: 12,383
Taxes & Virus's R-US, NY
|
Out of the box MP heads usually flow around 375cfm Uuuuhhhh........... not even close. I tested two heads from two different pairs.....355-375 has been our experience with the MP heads. What have you found?
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: fast68plymouth]
#2683027
07/31/19 10:34 AM
07/31/19 10:34 AM
|
Joined: Mar 2011
Posts: 3,066
Michigan
A727Tflite
master
|
master
Joined: Mar 2011
Posts: 3,066
Michigan
|
Out of the box MP heads usually flow around 375cfm Uuuuhhhh........... not even close. I was waiting for you to reply. I had a head flowed - flowed 318 OOTB This is the Eddy head made for and sold through Mopar Performance back a few years ago.
Last edited by Transman; 07/31/19 10:36 AM.
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: A727Tflite]
#2683041
07/31/19 11:05 AM
07/31/19 11:05 AM
|
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
|
I don’t think I’ve ever flowed a pre-Edelbrock MP aluminum Hemi head in its “ootb” form, but with a valve job and bowl blend by Jeff at MCH...... it was 317@.700.
Normal “full porting”, no tubes 365@.700.
Without digging through my notes I want to say the Edelbrock version was right around 320...... ootb.
(Found my notes 317 ootb, 323 with 3 minute blend)
A really nice original 559 head with the seats touched up and Manley valves was 311.
The best of the stock type MP heads I’ve tested was the latest version of the 559-M head, which went 335.
The earlier version had a flatter floor and approach to the bowl/short turn, and ootb it was like 315.
Indy SR head with a valve job and mild bowl blend is 337.
I’d have to really dig deep to find some numbers on a stock type stage V head....... but my recollection is, without porting, they’re right in the mix with these other heads.
The MP Edelbrock head with a basic clean up of the entire port ends up in the 350’s.
A more serious effort, but still no “tubes” gets you another 20cfm.
A normal “full porting”(no tubes) of the later 559-m is also in the 370’s.
Full cnc port job on an original 559 head from MCH, with some tubes, right about 400cfm.
Edelbrock Victor -ootb = 400cfm
Recut seats and blend 420.
Of the “stock type” hemi heads, I like the Ede made MP heads the best.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: fast68plymouth]
#2683063
07/31/19 11:58 AM
07/31/19 11:58 AM
|
Joined: Jan 2003
Posts: 17,836
S.E. Michigan
ZIPPY
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 17,836
S.E. Michigan
|
Here are the OOTB numbers provided to me by Chrysler Engineering circa 2008.
110-M heads are the '06, Edelbrock/MP are the '07.
They seem to agree with the 317-320+ ballpark, right in there....
I expect given the source of this information somebody will throw darts at it, and that's okay with me.
Last edited by ZIPPY; 07/31/19 12:02 PM.
Rich H.
Esse Quam Videri
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: ZIPPY]
#2683077
07/31/19 12:21 PM
07/31/19 12:21 PM
|
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
|
One thing I’ve noticed with hemi heads more than anything else I’ve tested...... on a flow bench that has a “back wall” (like the SF-600), if you don’t turn the head around when you flow the ex ports, the numbers will be noticeably lower.
Most of the stuff I’ve tested, turning the head around does almost nothing.
Also........ the Hemi heads seem to pick up noticeably with a flow tube on the exhaust.
That being said, the ootb numbers for the Ede made MP head, ex facing the wall and no tube is around 185 on my bench, and like in the graphs...... it gets there at a pretty low lift.
With the normal full port, ex port facing out, 2-1/8” flow tube attached, you’re in the 260 range by about .500 lift...... then it just stays there as the lift increases.
The victor with the valve job and bowl blend, also with the ex facing out and flow tube attached is in the 300@.700 lift range.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: fast68plymouth]
#2683203
07/31/19 08:11 PM
07/31/19 08:11 PM
|
Joined: Jan 2003
Posts: 3,504
DFW
mr_340
master
|
master
Joined: Jan 2003
Posts: 3,504
DFW
|
Anyone ever try a BBC 2.25" valve in a Hemi? It killed the flow up to around .700" lift and then it was about the same. I tried it just to see how it would work. It didn't.
Last edited by mr_340; 08/02/19 02:27 PM. Reason: Misspelling.
Floyd Lippencott IV
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: fast68plymouth]
#2683205
07/31/19 08:20 PM
07/31/19 08:20 PM
|
Joined: Mar 2011
Posts: 3,066
Michigan
A727Tflite
master
|
master
Joined: Mar 2011
Posts: 3,066
Michigan
|
I don’t think I’ve ever flowed a pre-Edelbrock MP aluminum Hemi head in its “ootb” form, but with a valve job and bowl blend by Jeff at MCH...... it was 317@.700.
Normal “full porting”, no tubes 365@.700.
Without digging through my notes I want to say the Edelbrock version was right around 320...... ootb.
(Found my notes 317 ootb, 323 with 3 minute blend)
A really nice original 559 head with the seats touched up and Manley valves was 311.
The best of the stock type MP heads I’ve tested was the latest version of the 559-M head, which went 335.
The earlier version had a flatter floor and approach to the bowl/short turn, and ootb it was like 315.
Indy SR head with a valve job and mild bowl blend is 337.
I’d have to really dig deep to find some numbers on a stock type stage V head....... but my recollection is, without porting, they’re right in the mix with these other heads.
The MP Edelbrock head with a basic clean up of the entire port ends up in the 350’s.
A more serious effort, but still no “tubes” gets you another 20cfm.
A normal “full porting”(no tubes) of the later 559-m is also in the 370’s.
Full cnc port job on an original 559 head from MCH, with some tubes, right about 400cfm.
Edelbrock Victor -ootb = 400cfm
Recut seats and blend 420.
Of the “stock type” hemi heads, I like the Ede made MP heads the best. Which head is the MP P5153875 in you comments above?
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: A727Tflite]
#2683219
07/31/19 08:47 PM
07/31/19 08:47 PM
|
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
|
Which head is the MP P5153875 in you comments above?
These: Without digging through my notes I want to say the Edelbrock version was right around 320...... ootb.
(Found my notes 317 ootb, 323 with 3 minute blend)
The MP Edelbrock head with a basic clean up of the entire port ends up in the 350’s.
A more serious effort, but still no “tubes” gets you another 20cfm. One of the 370cfm sets I did went on a 12.5:1 496 and made right around 800hp.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
|
|
|
Re: MP Hemi head porting, HP improvement?
[Re: fast68plymouth]
#2683222
07/31/19 08:57 PM
07/31/19 08:57 PM
|
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
fast68plymouth
I Live Here
|
I Live Here
Joined: Jan 2003
Posts: 14,491
So. Burlington, Vt.
|
IMO the Hi-Po heads will make at least 100 more hp than my 426 SR's but for my current package they aren't a very good fit. They have poor port velocity down low and my torque numbers suffer drastically. They want lots of rpm to work and the hp peak was north of 7000.
You’re around 600 cubes too, right? Just proves that not every combo benefits from “bigger” heads.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
|
|
|
|
|
![[Linked Image]](https://s73.photobucket.com/user/DaveRS23/media/2017-10-19%2012.43.48_zpsslj7wpfg.jpg.html)
![[Linked Image]](https://s73.photobucket.com/user/DaveRS23/media/2017-10-19%2012.44.05_zpsbkbrjyiv.jpg.html)
