Looking for a few tips on porting 351c 4v heads
Moderator: Team
-
- Guru
- Posts: 2858
- Joined: Thu Jan 06, 2011 8:57 am
- Location:
Re: Looking for a few tips on porting 351c 4v heads
[quote="thomas butt"
- Have guys done this with a 4v head? Would be interesting to see power potential of a properly ported 4V with a 2.12 or 2.15 valve and even 1.6 exhaust (if possible)[/quote]
Ford actually made that combination in 1973 or so for some application, a large 4V port, open chamber and the 2V size valves 2.040 1.650. My data on a 4.030 bore is this:
D3ZE head:
INT
.100 59
.200 136
.300 181
.400 226
.500 262
.600 285
.650 289
.700 285
EXH
.100 51
.200 98
.300 135
.400 162
.500 174
.600 182
.700 183
- Have guys done this with a 4v head? Would be interesting to see power potential of a properly ported 4V with a 2.12 or 2.15 valve and even 1.6 exhaust (if possible)[/quote]
Ford actually made that combination in 1973 or so for some application, a large 4V port, open chamber and the 2V size valves 2.040 1.650. My data on a 4.030 bore is this:
D3ZE head:
INT
.100 59
.200 136
.300 181
.400 226
.500 262
.600 285
.650 289
.700 285
EXH
.100 51
.200 98
.300 135
.400 162
.500 174
.600 182
.700 183
-
- Pro
- Posts: 217
- Joined: Sat Mar 08, 2014 12:35 pm
- Location:
Re: Looking for a few tips on porting 351c 4v heads
Ford actually made that combination in 1973 or so for some application, a large 4V port, open chamber and the 2V size valves 2.040 1.650. My data on a 4.030 bore is this:DaveMcLain wrote:[quote="thomas butt"
- Have guys done this with a 4v head? Would be interesting to see power potential of a properly ported 4V with a 2.12 or 2.15 valve and even 1.6 exhaust (if possible)
D3ZE head:
INT
.100 59
.200 136
.300 181
.400 226
.500 262
.600 285
.650 289
.700 285
EXH
.100 51
.200 98
.300 135
.400 162
.500 174
.600 182
.700 183[/quote]
Good info! Looks like the smaller exhuast really helped at .200 &.300. I'd like to see one ported
Seems like intake valve needs to stay big.
Anybody know the details of Ronnie Crawfords 310" boss motor?
Re: Looking for a few tips on porting 351c 4v heads
what intake are you going to run? have you decided on how much stroke you are going to do?
"Anyone who thinks the low RPM engine will be faster just does not have as much experience as the rest of us" -The late, great Joe Sherman.
You wont beat anyone if you do everything the same as everyone.
You wont beat anyone if you do everything the same as everyone.
Re: Looking for a few tips on porting 351c 4v heads
Hi
Where is the intake port minimum cross sectional area in the 4V CC or OC cast iron celevand heads positioned ?
and
What is the minimum cross sectional area measurement ?
thanks
Where is the intake port minimum cross sectional area in the 4V CC or OC cast iron celevand heads positioned ?
and
What is the minimum cross sectional area measurement ?
thanks
-
- Pro
- Posts: 217
- Joined: Sat Mar 08, 2014 12:35 pm
- Location:
Re: Looking for a few tips on porting 351c 4v heads
Intake: Edel 2861. Probably 3.7" using stock crankcab0154 wrote:what intake are you going to run? have you decided on how much stroke you are going to do?
Re: Looking for a few tips on porting 351c 4v heads
Buggar no one knows where the standard 4V CC or OC MCSA is from the factory , I'm about to start improving my 4V CC factory cast irons so as this thread is titled " Re: Looking for a few tips on porting 351c 4v heads".
They ( 4V's ) are definitely are to large for a 351C@7000RPM with a port entrance area of 4.53insq and feeding a 2.19 diameter intake valve.
I have ordered some mold casting rubber and will have to do it the old method cut and slice and graphpaper it. With all the people out there with their new CNC porting machine you would think someone has digitised the a full set of standard factory cast iron 4V's and one could look at prity pictures n 2D/3D and share that information.
Here is my attempt to 3D draw a 4V port , i failed art classes at school , fill in the missing blanks if you know any of the standard port dimensions onto my drawing.
I have done a many simulations in PipeMax - MaxRaceSoftware Larry Meaux's and some very interesting results.
They ( 4V's ) are definitely are to large for a 351C@7000RPM with a port entrance area of 4.53insq and feeding a 2.19 diameter intake valve.
I have ordered some mold casting rubber and will have to do it the old method cut and slice and graphpaper it. With all the people out there with their new CNC porting machine you would think someone has digitised the a full set of standard factory cast iron 4V's and one could look at prity pictures n 2D/3D and share that information.
Here is my attempt to 3D draw a 4V port , i failed art classes at school , fill in the missing blanks if you know any of the standard port dimensions onto my drawing.
I have done a many simulations in PipeMax - MaxRaceSoftware Larry Meaux's and some very interesting results.
You do not have the required permissions to view the files attached to this post.
-
- Guru
- Posts: 1980
- Joined: Sat Mar 08, 2008 3:08 pm
- Location: Minneapolis
Re: Looking for a few tips on porting 351c 4v heads
What the actual number is I can't even remotely remember.. but the MCSA is at or just dropping over the apex of the SSR. Unfortunately there is just not enough material to fix it completely with a big valve size and stay out of water. You can really help port stall and turbulence issues with very small valvestems/guides/and additional guide boss streamlining. Many just cut out the factory iron guide bosses altogether for max effect.
A smaller valve can help matters because then you have more lattitude to build a more efficient shape on the short side. Valve curtain area gets smaller but the port gets better to more than make up for the loss in valve size. Hope that helps at all.
A smaller valve can help matters because then you have more lattitude to build a more efficient shape on the short side. Valve curtain area gets smaller but the port gets better to more than make up for the loss in valve size. Hope that helps at all.
-
- Pro
- Posts: 217
- Joined: Sat Mar 08, 2014 12:35 pm
- Location:
Re: Looking for a few tips on porting 351c 4v heads
Awesome info. Thanks. Here is a pic of a D3 intake port where the floor is angled. Why the angle? Better swirl?groberts101 wrote:What the actual number is I can't even remotely remember.. but the MCSA is at or just dropping over the apex of the SSR. Unfortunately there is just not enough material to fix it completely with a big valve size and stay out of water. You can really help port stall and turbulence issues with very small valvestems/guides/and additional guide boss streamlining. Many just cut out the factory iron guide bosses altogether for max effect.
A smaller valve can help matters because then you have more lattitude to build a more efficient shape on the short side. Valve curtain area gets smaller but the port gets better to more than make up for the loss in valve size. Hope that helps at all.
You do not have the required permissions to view the files attached to this post.
Re: Looking for a few tips on porting 351c 4v heads
What is that a spy photo taken with an 80's cuff link camera?
-
- Pro
- Posts: 217
- Joined: Sat Mar 08, 2014 12:35 pm
- Location:
Re: Looking for a few tips on porting 351c 4v heads
If you look at a 4v port it makes a turn around the pushrod and widens to the left a great deal (port get shorter yet wider before the bowl). it seems like none of the port fillers, tongues, take the widened section into consideration? They fill the front part of the port but taper by the time the floor starts the short turn...
-
- Guru
- Posts: 1029
- Joined: Mon Sep 10, 2012 1:55 pm
- Location: Anaheim, CA
-
- Pro
- Posts: 217
- Joined: Sat Mar 08, 2014 12:35 pm
- Location:
Re: Looking for a few tips on porting 351c 4v heads
I am talking about a 351c 4v port onlypiston guy wrote:Totally different ports.
-
- Guru
- Posts: 1029
- Joined: Mon Sep 10, 2012 1:55 pm
- Location: Anaheim, CA
Re: Looking for a few tips on porting 351c 4v heads
The head began life in late '67. While they did have flowbenches to test with , the ports left alot to be desired. Race versions of the head( Trans Am heads) had the ports rewroked over "production" versions and made more power accordingly. Most of these heads were used up in Nascar engines and Pro Stock racers were left with the production heads. Lots of "Devcon" was used to make them flow. Ford's series of aluminum high port castings were superior almost out of the box.
Iron heads have always been very exhaust system dependent and require split duration camshafts to help the extreme flow bias. High port plates helped but didn't eliminate the problem.
Iron heads have always been very exhaust system dependent and require split duration camshafts to help the extreme flow bias. High port plates helped but didn't eliminate the problem.
-
- Guru
- Posts: 1029
- Joined: Mon Sep 10, 2012 1:55 pm
- Location: Anaheim, CA
Re: Looking for a few tips on porting 351c 4v heads
Kazoom wrote:in 69-70 Ford Indy designed removable/changeable intake port inserts for the 4V head for Trans-Am racing for more velocity with the Small 302ci eng...
http://www.ponysite.de/transam_stevens3.htm
Port inserts were not SCCA legal. The heads pictured are T/A heads and as I mentioned far different than production heads. There was also a "small port" head created for 1970/71 use that featured "filled" intake ports. I have Bud Moore engine build sheets that note their use and the comments are not great. Power was down on them and few were used. Some raw castings are "floating around" and may never finish machined.
-
- New Member
- Posts: 3
- Joined: Mon Sep 12, 2011 10:29 pm
- Location:
Re: Looking for a few tips on porting 351c 4v heads
Why does the port shape here http://www.ebay.com/itm/Ford-302-351C-C ... 1935937328 look drastically different then what you have pictured? I understand it's the "speedmaster" brand but AFAIK speedmaster and procomp are one in the same.
Here's a question for you, what ever happened to the procomp electronics website?
More importantly, why is it that most professional builders won't reccomend using those brands versus other options, and a large number would reject using them altogether? Why does it seem that there are more horror stories regarding the use of those brands then praise/achievements? Also, why is it that you find everybody who contradicts you as a troll?
Here's a question for you, what ever happened to the procomp electronics website?
More importantly, why is it that most professional builders won't reccomend using those brands versus other options, and a large number would reject using them altogether? Why does it seem that there are more horror stories regarding the use of those brands then praise/achievements? Also, why is it that you find everybody who contradicts you as a troll?