This info was taken from a compilation of posts that Jon Kaase made while he was develping his Ford 429/460-series P-51 cylinder head 10+ years ago. It was edited by the person who compiled them originally to reflect just the info Kasse was gathering from his dyno tests and his opinions. Not Mopar, but contains some interesting info & test data, IMO.

Also of interest is how Kaase was posting this stuff on a Ford enthusiast web site and getting feedback from the potential customer base, rather than just doing it behind the scenes and then dropping it on the pubic.


Info on P-51 heads

We have been testing a new set of heads (P-51) on a 514 crate engine. The engine has Diamond flat tops, with 2 sets of valve pockets (CJ&SCJ), and a Comp Cams 265/269@.050, .788 lift, 106 LSA roller cam. It has about .015 to .020 deck clearance. We redid the valve job a few times and the heads are 77 cc right now. It figures to 11.95 to 1 compression. It has stock Ford truck rods since it is an early built 514. The heads are as delivered, with CNC chambers and short turns. I'll check flow soon but would guess 400 on the intake. All of the following tests are on race gas. The best so far is 782HP at 6700 with 725 FT/LBS at 5200. These heads are exactly the way we plan to sell them. The manifold has been a stock Victor 460 with a 1150 cfm Demon carb. We have also been working on our own manifold and right now it is a little better than the Victor. Tomorrow we plan to run a stock set of new Ford SCJ's. It will be a fair test, but I'm hoping they're not as good as the P-51's.

Years ago we did make 781 with the first SCJ test heads. I think the difference was that those heads were ported and rubbed on for months, and it had a real good box-type pan. It was also a different dyno. We did however, dyno this engine today with a new set of SCJ's. It had a best of 751 HP with 717 ft lbs. (about 30 less than the P-51's)


2nd update, P-51 heads

As discussed before, we have been running our new heads on a 514 crate motor, with a best of 782 HP. We then took a new set of Ford Motorsport SCJ's off the shelf, robbed the springs and retainers from our heads, and ran them on the dyno. The best was 751. This was as fair a test as we could do. Same weather,etc., the only difference was the head castings with valves. The tough part about this is the fact that we are trying to improve on a head that is really good. I have one more cam to try, maybe tomorrow. My goal is to make 800HP with this head on a motor this size, as delivered. I will try to answer some questions I've seen here:

1. The chamber is CNC ported with a slightly better design.

2. The valve bowls are CNC ported to the top of the short turn.

3. The intake short turn approach to the seat and port width at the short turn have been modified to help eliminate the turbulence that is common with high airflow and low port entries.

4. The water jacket has been changed to allow for more agressive porting at the intake short turn floor and side.

5. The intake rocker stud has had an angle and location change. This will help accomidate a larger selection of rocker arm brands. It will also help keep the geometry right when longer valves are used. We are looking at assembling these heads with .100" longer valves.

6. Valve pockets and locations are the same a SCJ's.

7. Pricing should be in line with or slightly less than brand F.


3rd update, P-51 heads

We changed cams today, from the 265 cam to a 272/280@.050, .788 lift, 106 LSA roller cam, installed our heads (P-51) back and made a best of 807HP@6600. I'm getting a little scared of the stock truck rods! This is with unported heads and unported victor intake. We have a homemade intake that peaks the same as the Victor, but has a little more downstairs. If and when we get this manifold a good bit better than anything else, we will try to put it into production. I'm out of my element with the single 4-bbl intakes, but I'm learning. We will be working on manifolds for a while because I don't want to port on the heads yet. We're trying to offer packages that will not require porting. Eventually I want to port on the ex ports some and see how much it's worth. If anyone has something they want to see us try on this engine, respond here and we'll see if we can do it. Also, any advice on intakes would be well received.

We have a 460 Motorsport short block and I plan to change it with the 514 assembly.

Sometimes the real challenge is to see how good you can make a cylinder head and still have it remain exactly stock in appearence and outside dimention. Raising the exhaust port would have been the easy way out. The intake is the same way. I never thought about it much until Larry Olson (EPD Cylinder heads) told me that anyone can get a race type head to flow good, but it takes a real man to get one with the port entry down on the deck to flow well. After we run Scott's ported Victor, I may port the exhausts just to see what is's worth. Then again we could take the easy road and raise it up.


4th update, P-51 heads

Today I flowed as delivered SCJ and P-51 heads. It was on a 4.390" bore and with a Ford Motorsport exhaust valve. The P-51's dynoed about 30 better than the SCJ's a few weeks ago.

Intake - SCJ / P-51

100 - 104 / 105
200 - 166 / 175
300 - 215 / 258
400 - 285 / 330
500 - 321 / 375
600 - 337 / 401
700 - 346 / 412

Exhaust - SCJ / P-51
100 - 98 / 103
200 - 126 / 137
300 - 158 / 170
400 - 186 / 199
500 - 210 / 223
600 - 224 / 242
700 - 234 / 254

When the heads leave our shop I will have already hand blended the casting with the machine marks in the valve bowl and short turn. The heads we've been testing and flowing have been done this way. In all fairness, (espically to those who have already bought Ford's SCJ head) the SCJ's can be ported to flow every bit as good as the P-51. The difference is that our head is already about as good as you can port one. Also, there is more aluminum under the short turn floor and left side wall, where we have been known get the swim fins and mask out. We are now porting on the exhaust ports and will dyno test it with this being the only change.


5th update, P-51 heads

I wanted to find out how responsive the exhaust side of the head is to porting. When I started, the unported exhausts flowed around 253 @ .700". We ground the left wall to be a straight line from the bowl to the exit, grinding through the bolt boss and leaving the stud exposed. Also, we streamlined around the guide and completely ported and polished and made a max effort. It flowed about 265 when finished. When we dynoed it, the power was exactly the same with no other changes to the motor. (still a little over 800HP) I was surprised it didn't help at least a little. It could be with the seat ID of 1.56" and 1.76" valve; that is the limiting factor. Still, 800 is pertty good for unported intake ports. Then we ran two days of manifold tests.

Manifold tests

We have been trying our best to come up with an intake manifold that is better than anything you can buy. We have run four different intakes, all within a few hours of each other. The bottom line at this point is that a stock victor 460 is about as good as anything you can do. We tried a port matched Victor, but it was only a little better than a stock one. If you grind out the carb hole square, like the dominator gasket, and run a 2" square open spacer it helps 8-10 HP. I was real excited to get the new TFS R-series 460 intake. It's made to fit their street head, so the port location is low on the SCJ or P-51 head. As it came, it made 50 HP less than the stock Victor 460. I couldn't believe it. With that behind us, I ground the port exits to match the SCJ gasket, going up the runners as far as possible. This helped quite a bit as it made 790. Then we cut the carb hole out to fit a dominator and changed the carb bolt pattern. ( we had been using an adaptor) This brought the power to 805. It was about as good as a Victor 460, only a lot more work. Then I decided to fill the floor of the exits to look like a Victor, going in 4-5". It was about 1/4" at the gasket, tapering to 0 up inside. All this and it made no difference. Not anywhere. What does all this mean? Don't run the TFS on anything but their head or any base iron head. With enough work it may be better than anything out there, but I have not found the sweet spot on it for the P-51 head. Randy Malik is working on his own design manifold and I hope to run it soon.

We will try a tunnel ram next week. A Weiand and our own. On manifolds; the Trick Flow is larger than the Victor, at the port entries and in the middle of the port. It looks really good and is easy to port. It's just not any better anywhere than the victor, at least on this motor. This makes me think that porting the victor and making it overall larger would not help much, if at all. The best overall intake we've tried is a homemade one that is real small in the midsection of the runner. The thing that keeps bothering me is that my Enginemasters 507 Pontiac is 40 ft/lbs and 50 HP better than the Ford. The short block and heads are no better than the Ford, and I think the big difference is the manifold. That's why I've been working in intakes so hard. I think we'll get there but it won't resemble anything you've seen before.

A good portion of the allure of the Pontiac for the Enginemasters was the manifold and the need for the 1" spacer. The center four runners on the Pontiac, when you include the spacer, were about 4" longer than the Ford. That's the battle we're facing right now.

We have bought an Edelbrock Torquer II and will dyno it tomorrow. Also we will be running a Weiand tunnel ram and also one we had cast up.


6th update, P-51 heads/ Torker II intake

After several requests, we bought an Edelbrock Torker II intake and dyno tested it today. The best this 514 Ford crate motor has been is 806HP/ 720 Ft/Lbs. This was with two different Edelbrock Victor 460s, and a modified Trick Flow R series 460. They were all about the same. The Torker II, out of the box was not bad as it made 746HP/700 Ft/Lbs. It was about the same as the un-modified Trickflow. Both were made to fit the low port base type head but they will bolt onto the SCJ and P-51 head. Then we ported the Torker II to match the P-51 head at the roof. It looked like a tall racetrack pattern port. I didn't make it any wider than the casting, just taller by about 3/8". You don't have to port in too far, about 1 1/4" in. It took 40 minutes. The result was 766HP/710 Ft/Lbs. The average power 4500-6500 was 20 less than the best runs ever with the other race manifolds. This intake is 2 1/2" lower than the Victor. Not bad for a $250 street intake that will clear most hoods! A tunnel ram will be next.

We ran the same 1150 King Demon in all tests thus far. With the TorkerII, I used a Wilson funnel down type 2" adaptor. This setup has shown to be 10HP less than our best 2" open dominator spacer with a 4 hole shear plate on top. If we were to cut out the carb pad on the TorkerII, to a dominator size and change the bolt pattern, I think it would be 10HP better yet. The trick flow picked up 10 when we did this.


7th update, P-51 heads on 466

Today I changed the 514 Ford short block (really 521") to a 466 Ford Motorsport assembled short block. Besides the stroke difference, 4.3 to 3.85, the compression on this one was 10.2 to 1. The 514 is 12 to 1. It has cast pistons but I doubt they would hurt the power. With a 256/262@.050, .761 lift, 108 LSA roller cam the 466 made a best of 678 HP and 598 Ft/Lbs. I changed the cam to the 272/280@.050, .788 lift, 106 LSA roller cam, the one that was the best in the 514. It then made 701HP, 596 Ft/Lbs. The 466 was about 100 HP less, 55"less and 2 points of compression less. Still it's not bad for a passenger car short block. You have to figure that compression would have helped a ton with the bigger cam. The cast pistons were .010" deck clearance, plus 16cc dish and valve pocket. They already had the SCJ intake relief. I used the unported Victor intake with a 1150 King Demon. All and all, not bad. It took a load good at 2300 rpm with both cams, a little better with the 256-262 cam. Peak power was at 6500, peak torque was at 5000. It was around 450 Ft/Lbs at 2500 rpm. The 256-262 cam fell off 80 HP more than the 272-280 cam at 6800rpm. It would be a pretty good street engine with the smaller one.

Tunnel ram on the 514

Last week we did run a tunnel ram. It was an old Weiand that had a 4500 two peice top. I had built it in 1986 and ran it on the original A-429 heads. I was a little shocked as it was only a slightly better than the Victor 4-bbl. Peak power was 815. There were a lot more numbers above 800 than with the 4-bbl though. The torque was about 10 better than the 4-bbl. We have another tunnel ram to run soon. This one we designed and had cast.


8th update, P-51 heads. Questions this time

We are trying to get parts ready for the upcoming cylinder heads. We're having 2000 valves made. They are the same supplier as Ford Motorsport, with a few design changes being made. They'll be .100" longer and the intake valve will come with a 30 degree backcut. Guide plates are being made and ARP studs are on the way. For assembled heads, we're trying to come up with good quality components, but keeping the price low is difficult when using top shelf parts. Ford's assembled heads are $400 more than the bare ones (per pair). Figure $240 for valves, $30 for guide plates, $32 for studs, $20 for seals. That only gives us $78 for the springs, retainers, locks and spring locaters. You can see the problem. Also, since we're planning on 2.00" installed height, the springs may be priced higher just because they are taller.

So here are my questions: I need to come up with 3 or 4 affordable spring types to offer with these heads, along with retainers and locaters. Along with that, I would like to get some opinions on what the most popular rocker arms people will be using on these heads. I would like to be able to hit a guy's pushrod needs dead on if I knew what kind of rocker he has and what the valve lift is. A Harland Sharp rocker may need a different pushrod length than a Crane. We will try to work out all these combinations.


9th update, P-51 heads

We sent one of the heads to Jomar to have a new stud girdle designed, since the rocker studs have been moved to a more friendly position and angle. Before disassembly, we ran the 466 again and made a best of 722HP, 600 ft lbs. This is a stock +.030, 460 Ford short block with cast pistons, 10.2 compression and never been apart. If we run it to 7200 a few more times it may come apart on its own. Thanks to all who responded to my questions on the #8 post. We are machining heads this week and hope to have them ready within 10 days

Brad, lots of good information there, if I were a BB Ford guy, I know who would be in line to get my money! Communication and flexibility are key components for success, can you imagine Indy being so open and helpful? Good for the Blue Oval guys and good on to Kaase!

Here is another very good detailed write up on some Ford FE cylinder head development.

http://fepower.net/simplemachinesforum/index.php?topic=6987.0

Thank you, I really enjoy reading Kaase tech info. He is one of the reason I like the 385 series.

I'm helping with a Ford 509 build right now so the information is useful. This engine isn't making much power with Edelbrock RPM heads and a flat tappet cam so the owner is looking to improve things. He would love to have 700 hp with 10:1 compression but I have a feeling it isn't quite as simple as Kaase says!

Good reading, thanks for posting.

Good read Brad. Thanks for putting that up as it gives me a couple ideas as far as cam and intake on my 511.

That is a great read.......
Here’s what stood out the most to me......

Look at these intake port flow differences(57cfm avg gain from .400-.700) .........and then digest that on a 12:1 514” motor with a decent sized roller cam...... the power difference was only 30hp in a true back-to-back dyno test.


Pretty noticeable change in cam duration(on a combo that really seemed like it could use it) was worth 20hp.

Fully ported Ex port worth zero gain.


Does it continue on?
I was hoping to see what happened with their new TR.


Years ago when I was working with a builder trying to come up with a nice package for a couple of the local oval track classes....... and we tried all kinds of stuff that didn’t make any difference.

Very smart guy.
My choice to replace Smokey in the "when they wrote the rules they didn't think of THIS" category, read his EMC stuff.

I would welcome 25-30hp with a cam swap. I will have to check, but I think my flow numbers on my victors are similar to the SCJ head.

Here are my flow numbers again. They are not far off from the SCJ head. I too am interested in the tunnel ram results. Good stuff.
.100-75.1
.200-164.7
.300-222
.400-278.6
.500-324.2
.600-347.8
.700-356

There wasn't any more info than what I posted above from the Kaase P51 posts I came across.

After you read all the Kaase info on his P51 heads then you need to read the EngineLabs dyno test where the AFR heads eat the P51 for lunch. I don't know the truth of all of this since I don't spend all day on the dyno with a 460 Ford, but the back and forth is interesting. I'm helping out with a mud bogger engine build right now that is getting the AFR heads rather than the P51 and some of it is due to this article. Guess we'll see if it really works or not.

https://www.enginelabs.com/engine-t...d-with-air-flow-researchs-bullitt-heads/

I’m gonna say(without even reading the article)...... this will def fall into that “it depends” category.