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Cylinder Head Info

January 26 2010 at 5:06 PM
Dave O'Hagin  (Login DJOHAGIN)
from IP address

The following information comes from many sources, and different forums.  I wish to thank all the individuals who gave their time and experience to share.

This info was last revised 1/16/2010.

This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:14 PM

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General Information

January 26 2010, 5:08 PM 

Port Measurements

These measurements are of the minimum height and width of the respective intake ports. This represents the choke point in the port.

Courtesy of ScottJ.


Iron CJ and P.I.-------------------------- 1.75" x 1.93"

395 cfm AR 1st gen aluminum CJ----- 1.84" x 1.74"

Stock D0VE------------------------------- 1.66" x 1.80"

365 cfm D0VE---------------------------- 1.74" x 1.85"

380 cfm D0VE---------------------------- 1.79" x 1.87"

Fuelie E7TE------------------------------- 1.75" x 1.52"

Stock D3VE------------------------------- 1.70" x 1.80"

Useful links:

B.F. Evans Ford Dealer (Lem Evans):


DSC Motorsports:




Eliminator Products:


Ford Racing Parts:


High Flow Dynamics (Paul Kane):


Jon Kaase Racing Engines:


MPG Head Service:


Price Motorsport Engineering:


"Pro-Filer" Performance Products


Rein"Car"nation High Performance (Scott J):




Machined Surface Finish

The factory Ford engine shop manual (460 engine) specifies a head gasket surface finish of RMS 90-150 on the block and RMS 60-110 on the cylinder head. (RMS values are outdated measures.) RA is the modern method of surface analyzing, and has been designated by the International Standards Organizations (ISO) as the correct practice for measuring the roughness of a machined surface. RA is roughly 90% of RMS. Multiplying RA value times 1.11 will give you an approximate RMS value. A great link explaining all of this much better than I can:


Valve Info

S.I. and REV are the same valves. They are different companies, but they share their inventory. They will make valves to your specs if you provide a print. They are made in

REV finishes their valve a little nicer than an S-I, but the SI valves are just fine.


SI has a catalog that's sort of confusing, but if you call them they will point you in the right direction. The PortFlow and Silverline valves will work with fine results in all sorts of racing and street applications.  You have to remember that they have several levels of quality depending upon the intended application. The Portflow valves, for instance, are an inexpensive swirl polished stainless valve that's intended for mild applications, something with a solid flat tappet cam etc.   They have been used them in circle track engines with fine results, but on two barrel stuff, it is better to use their premium valves in the exhaust side.

Their SilverLine valves are very nice quality and they are suitable for racing roller applications. When you talk to them be sure to ask a few questions, tell them about your application and they will sell you the right stuff. Their valve seats are good too.

Titanium Valves

Backcutting titanium valves is dependent on the manufacter. Ferrea valves are usually a non-issue where as some Manley valves have such a thin head thickness, that you can hardly get a backcut. You have to check to see if there is enough margin thickness, like around .070" to .075" and then enough seat width, in order to have something to backcut.

Often individuals want titanium valves for their street engines, which is do-able, but titanium does not provide a good "wear" surface.  You need to moly coat the stems and the tip requires protection. You need either hardened stellite tips installed or lash caps, for race engine use.  In addition to the above, you will need a very expensive DLC coating, or TiAlN coating on the seat contact surface.

Head Bolt Data

This is the measured the height of the various castings at the outside roll of bolt holes, in other words, where the machined surface or flat is for the head bolt washers.

1. Factory D3VE cast iron head = 3.800"
2. Ford SVO A-429 CJ alum. head = 3.945"
3. TFS Street/Strip CJ alum. head = 3.910"
4. Ford Kaase SCJ alum. head = 4.000"

This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:10 PM

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Re: Cylinder Head Info

January 26 2010, 5:12 PM 

Cylinder Head Pecking Order

It helps if you divide all the heads into four major families:

1)  Hemi Heads

2)  Pro Stock Wedge Heads
3)  A-460 Heads
4)  Standard Layout Ford Production Heads

In regards to the head hierarchy, Probably more importantly than the best to worst of the heads is who you choose to do the valve job, the porting and flow testing of the heads. In other words, the quality of the work.  It is possible to have good quality Blue Thunder "B" heads outflow poor quality EX 514 heads, for example.  A head that is lower in the list can surpass a head that is above it due to being properly prepped.

Generally speaking, the aluminum stock layout heads are better than the cast iron heads, because all the aluminum heads have a better exhaust port. They flow more because they are designed better.  The intake ports of our Ford OEM cast iron heads and aftermarket cast alum. Ford heads are much closer in parity than the exhaust ports. Nobody needs to make any apologies for our OEM cast iron intake ports. They are good, specially the DOOE-R CJ head.

As for the letters A, B, C, and etc. on the Ford stock cast iron heads and later aluminum heads, this is just Ford's nomenclature for distinguishing early or original versions of parts from later versions of parts. "A" is generally the first version of a head and then "B" is the second, "C" is the third and so on. Most always the later versions have some design change/upgrade in order to imporve the part.

For example the first Pro Stock wedge head back in the early/mid 80's was the A-460, then we had B-460 heads, and by the mid 90's we had the C-460 head, then D-460 and the current NHRA legal Pro Stock head for Ford is the E-460 head. That's where we are at now.

BBF Head Hierarchy from best to worst

1. C&C C-441 Hemi
2. C&C B-441 Hemi
3. HFD Pentroof Hemi
4. C&C A-441 Hemi
5. Ford Motorsport A-441 Hemi (No longer in production)
6. Indy Cylinder Hemi
7. Ford E-460 Pro Stock
8. Blue Thunder Thor Gen II
9. Blue Thunder Thor Gen I
10. Profiler C-Replacement
11. Ford C-460
12. Ford D-460 Pro Stock (No longer in production)
13. Ford Motorsport bastard Pro Stock (There are various stages) (No longer in production)
14. IDT Eliminator A-460
15. EX514
16. New TFS A-460 18-bolt
18. New TFS A-460
19. EX514 Cast Iron A-460
20. IDT Eliminator Cast Iron A-460
21. Older TFS A-460 (No longer in production)
22. Ford Motorsport A-460 (No longer in production)
23. Ford Motorsport A-460 (Ford exhaust port) (No longer in production)
24. Kaase Hemi
25. Boss 429 Replacement
26. Ford Stock Hemi (No longer in production)
27. TFS B-460 (small port) (No longer in production)
28. Ford Motorsport B-460 (small port) (No longer in production)
29. Kaase P-51
30. Ford Racing Parts SCJ
31. Blue Thunder CJ with Chevy exhaust flange
32. Blue Thunder CJ with raised Ford exhaust port
TFS Street
34. Blue Thunder CJ with stock Ford exhaust port location
35. TFS CJ (No longer in production)
36. Ford A-429 CJ (No longer in production)
37. Edelbrock CJ
38. Ford Cast Iron DOOE-R CJ (No longer in production)
39. Edelbrock 75cc
40. Ford Cast iron PI (No longer in production)
41. ProComp Aluminum 74cc
42. Ford Cast Iron C8VE (No longer in production)
43. Ford Cast Iron C9VE (No longer in production)
44. Ford Cast Iron DOVE (No longer in production)
45. Edelbrock 95cc
46. ProComp Aluminum 95cc
47. Ford Cast iron D3VE (No longer in production)
48. Ford Cast Iron E6TE (No longer in production)
49. Ford Cast Iron F8TE (No longer in production)
50. Ford Cast Iron "Fuelie" F3TE (No longer in production)
51. Ford Cast Iron "Fuelie" E7TE (No longer in production)
52. Ford Cast iron D2VE (No longer in production)
53. Ford Cast Iron D8TE (or E9TE, to be confirmed) (No longer in production)

This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:15 PM

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Re: Cylinder Head Info

January 26 2010, 5:18 PM 

Stock Cast Iron Heads

Head Castings



These heads are basically all the same. Some castings have thermact-air bosses and drilled passages, and some do not. The size of the thermact-air bosses also varies. With-in the three casting, there is also engineering revisions, i.e. DOVE-A, DOVE-B, DOVE-C. Chamber size is about 77 cc, and can vary +/- from that. The stock size valves in these heads are 2.08 for the intake and 1.65 for the exhaust. These heads can have 2.25 intake and 1.76 exhaust valves installed. The exhaust port shape is restricted quite a bit, and porting helps. After proper porting, all three casting flow the same. It should be noted, not only for these factory cast iron heads, that not only should the exhaust be ported, but the intake as well.



These heads are basically all the same. The E6s and F8s were cast as replacements for the D3s. Most of these casting have thermact-air bosses and drilled passages, but a few D3 castings do not drilled thermact-air passages. Chamber size varies from 92  to 100cc, so it is important to cc the heads. The chamber is .100 deeper than the early heads, and the valves are shorted that much as well. When replacing these heads with the early heads, the valves will be .100 closer to the piston, so take that into consideration. The stock size valves in these heads are 2.08 for the intake and 1.65 for the exhaust. These heads can have 2.25 intake and 1.76 exhaust valves installed. The exhaust port shape is restricted the most out of all the factory cast iron heads. After proper porting, all three casting flow the same. The exhaust cannot be make to flow like the early castings due to the short-turn on the exhaust being .100 shorter.


D2OE Police Interceptor Head


These heads were used on only "fleet" vehicles, while not necessarily police cars, but that was their biggest usage by far.  The intake and exhaust ports are halfway in size between a D0VE head and CJ head.  Chamber size varies from 88 to 95cc.  The stock size valves in these heads are 2.19 for the intake and 1.72 for the exhaust.


D0OE-R CJ Head


The D0OE-R heads. The intake port is the largest of all the cast iron castings. Chamber size is listed at 72cc and can vary +/- from that. The stock size valves in these heads are 2.24 for the intake and 1.72 for the exhaust. The exhaust port is also larger than the passenger heads, but the shape is similar, hence it is also restricted quite a bit, and porting helps.

Maximum Valve Lifts With Stock Heads

Courtesy of Randy Malik

Unmachined D3's with production length valves and stock retainers will allow about .560"valve lift MAXIMUM; maybe some heads might allow very slightly more.

Maximum Power with Stock Heads

Courtesy of Scott Johnson

With well worked max effort dove heads you can expect a maximum of about 700 to 725 HP given the intake port flow capabilities of the dove intake port.

On a 557 cubic inch motor, you can get 700 HP at 6K rpm with a Comp Cams XR292R cam and 10.6 to 1 compression ratio.

A 472 can make 718 hp at 7200 rpm with about 20 degrees more duration, higher valve lift and two points more c/r.

This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:19 PM

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Re: Cylinder Head Info

January 26 2010, 5:20 PM 

Stock Cast Iron Head Flow Numbers

E7TE "Fuelie" Head

Courtesy of Scott Johnson





F3TE "Fuelie" Head

Courtesy of Scott Johnson

2.19 x 1.76



D3VE Head

Courtesy of Scott Johnson



Ported Stage 2 standard flange on intake and Stage 2 on exhaust


DOVE Head (C8 and C9 heads will be similar)

Courtesy of Scott Johnson



Ported Stage 2 standard flange on intake and Stage 2 on exhaust


Maximum effort porting with blazing on intake and exhaust with Victor match
2.2 Intake and 1.8 Exhaust Valves


D2OE Police Interceptor Head

Ported D20E PI heads. Intake port and bowl opened up to 310cc. Exhaust just cleaned up with minor grinding. Intake valve used was Ferrea F5031 (2.25). Exhaust valve used was Ford Motorsport tulip A429 (1.76). 45 degree seats with back cut on intake valve. Hardened exhaust seats are a little big ID - about 1.588" - so might have hurt flow. Intake valve is unshrouded.

No pipe.

.800=348/199 <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />


Cast Iron D0OE-R

Courtesy of PullinBret

2.250 x 1.75


.100 - 72/55 76%
.200 - 137/109 79%
.300 - 200/134 67%
.400 - 266/149 56%
.500 - 289/157 54%
.600 - 317/161 50%
.700 - 337/163 48%
.800 - 350/???

Courtesy of Mike R.

2.245 x 1.725


.100 - 81/57 70%
.200 - 156/112 71%
.300 - 227/151 66%
.400 - 277/175 63%
.500 - 310/192 62%
.600 - 343/203 59%
.650 - 352/206 58%
.700 - 362/209 57%
.800 - 375/211 56%

Courtesy of Scott Johnson



Ported Stage 3 on intake and Stage 2 on exhaust


Courtesy of Charlie Evans

This is with 28 H2O, no test pipe on the exhaust, and numbers rounded off:

Lift Intake Exhaust
.100 71 59
.200 138 102
.300 206 129
.400 265 156
.500 310 175
.600 342 184
.700 364 188
.750 371 191

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Re: Cylinder Head Info

January 26 2010, 5:22 PM 

Aluminum Stock Layout Heads

Edelbrock Head

Differences Between Victor Jr, Performer RPM CJ, And Performer RPM Heads.

Victor Jr.

CJ cnc'ed CJ port match
Better springs and valves for a roller cam
75 cc chamber

Performer RPM CJ

CJ cnc'ed port match
Springs for hydraulic cam
75 cc chamber

Performer RPM

Standard size ports
Springs for hydraulic cam
Chamber sizes in 75cc and 95cc

All the above heads have the same exhaust port.

Trick Flow Street Head

Basic specs:

290cc intake runners and and 130cc exhaust ports raised .270 in. from the stock location
74cc combustion chambers
2.200 in. intake/1.760 in. exhaust size valves

Flow Number Tests

Courtesy of Charlie Evans

This post is about flow data with the Trick Flow Street Heads, they are in what I call the CJ Family of heads. Mike's heads have worked their way through here and will be shipped out Monday. They were assembled heads and the casting quality is excellent. The valve job to bowl transition was done by a CNC machine, not a bowl cutter, so that transition is really smooth. Intake valves are 2.200" and exhausts are 1.760". Chamber cc's were 72.

TFS gives the flowing flow numbers in there spec sheet.
Intakes; .100=72, .200=152, .300=219, .400=280, .500=320, .600=344, .700=350 cfm @ 28" H2O
Exhaust; .100=60, .200=110, .300=145, .400=180, .500=204, .600=225, .700=240 cfm @ 28" H2O

My baseline numbers on the heads out of the box were.
Intakes; .100=66.5, .200=143.8, .300=211.3, .400=274.8, .500=325.3, .600=351, .700=351.3, .750=351.8 cfm @ 28" H2O.

Exhaust; .100=50.5, .200=99.8, .300=138, .400=168.5, .500=193.3, .600=211.3, .700=222.5, .750=226.8 cfm @ 28" H2O.

After "Superbowl" blending and polished chambers we have.
Intakes; .100=67.7, .200=146, .300=214, .400=279, .500=328.4, .600=356, .700=354, .750=354 cfm @ 28" H2O.

Exhaust; .100=54, .200=104, .300=143, .400=178, .500=206, .600=227, .700=235, .750=235 cfm @ 28" H2O.

Fully ported we have.
Intakes; .100=69, .200=148, .300=233, .400=301, .500=335, .600=357, .700=373, .750=378 cfm.

Exhaust; .100=64, .200=116, .300=147, .400=178, .500=208, .600=228, .700=240, .750=240 cfm.

Generally bowl blending with most heads is more beneficial than it was with these heads. That's just a testimony as to how nice these heads are out of the box. The greatest gains seemed to be in the mid-range on the exhaust ports.

We think these heads represent a very good value for the dollar. My biggest complaint is that the spring seat cup is a stamped "cheap" piece that doesn't really stop any valve spring wiggle because it doesn't locate on either the guide or the machined aluminum on the outside. I'd recommend changing that for race engines, but it will be okay for street/strip engines.

Port Size

Courtesy of Scott Johnson

The TFS intake ports are all offset looking to match the Victor intake port centers. When this is done, are the ports the same size or is the TFS port slightly larger that the Victor intake port, and then, do you open up the Victor side some? I'm planning to use TFS streets on a large cube motor. Are the TFS different that the old A429 heads? A bunch of people use mildly ported A429 heads on 545 and 557 motors with good results.

The TFS streets have a Dove sized intake port on Dove port centers. The victor intake has dove sized port exits on the cj centers. When matching the tfs streets to the victor intake the ports are raised with 1 and 3 going left and 2 and 4 more straight up.

TFS streets will support 800 HP and after I port them the passange is pretty good sized. I have sold many pair to clients with 521 and 545 inch stroker combos. One client with a propane powered 545 with a blow through super charger is making 1050 HP.

Dont let the small port cross section fool you. The TFS streets are a very very good cylinder head. The TFS streets minimum intake port cross sections are quite similar to the first gen aluminum cj's which are not nearly as large as the iron cjs are.

Every pair of TFS streets I have done beat my ported first gen aluminum cj's by 15 cfm at .600", 7 to 10 cfm at .700" and 5 to 10 CFM at .800" The streets have a highly active, very efficient and well engineered intake port.

This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:26 PM

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Re: Cylinder Head Info

January 26 2010, 5:28 PM 

Blue Thunder CJ Heads

Blue Thunder "B" Heads - Flow Development Stages


Courtesy of Charlie Evans


I thought I'd post the stages of development that Lem and I went through on a set of Blue Thunder heads that we did for a friend of ours. He's using these heads on a pump gas engine. We did them last year.

The "B" heads are the ones with the Chevy style exhaust port, and as most of you know, it is a stock Cobra Jet style intake port. The valve sizes were 2.300" on the intake and 1.820" on the exhaust. All flow numbers are from our SuperFlow SFC 600 bench and are on a 4.625" bore and are @ 28" H2O. This data may be beneficial for some of you guys and Scott J. if you want to include them on your web site, for informational purposes you may. I'm not bragging or saying these are the best out there, because I'm sure they are not. I will say they are very good numbers and that they are good heads. These are an average of all 8 ports, with the decimals rounded off to the nearest whole number.

1. Out of the box - Unported - with a valve job.

Intake; .100=67,.200=129, .300=188, .400=251, .500=301, .600=322, .700=331, .750=335 total=1924
Exhaust .100=60,.200=114, .300=148, .400=176, .500=194,
.600=207, .700=215, .750=219 total=1333

2. "Super" Bowl Work/Blending

Intake; .100=71,.200=150, .300=209, .400=273, .500=329, .600=340, .700=343, .750=346 total=2061
Exhaust .100=61,.200=118, .300=158, .400=188, .500=213, .600=237, .700=258, .750=266 total=1499

3. Fully Ported Street/Strip

Intake; .100=72,.200=148, .300=213, .400=277, .500=331, .600=351, .700=356, .750=359 total=2107
Exhaust .100=67,.200=122, .300=163, .400=191, .500=215, .600=241, .700=265, .750=276 total=1540

4. Fully Race Ported. This past month we re-worked them again and Lem and I flowed them this morning.

Intake; .100=73, .200=152, .300=216, .400=281, .500=335, .600=363, .700=377, 750=380 total=2176
Exhaust .100=67, .200=122, .300=163, .400=198, .500=227. .600=251, .700=271, .750=280 total=1579

Dyno Results From These Heads

We've got some good dyno results from the heads that I gave you flow numbers on in the above post. Bob sent some pictures also and I'll see if we can get them up.

The engine is a pump gas 572 CID and with a flat tappet cam and a single 4 barrel we got 718 lbs. ft. @ 4900 rpm and 743 Hp @ 6100 rpm.

With a tunnel ram and 2 X 4 we got 746 lbs. ft. @ 4900 rpm and 779 Hp @ 6300 rpm.

IMO this is some of the best information we've put up on the forum. I'm surprised you all aren't tripping all over it. I've given you flow numbers on Blue Thunder heads and then I've given you dyno numbers from the 572 CID Pump Gas engine they were used on. Back to back numbers between a 1X4 single plane and a 2X4 tunnel ram. We've got pictures of the engine on the dyno and then in a boat. Sorry that it's taking a long time to load, but just bear with it.

The engine made over well over 700 lbs. ft. of torque from the start of the pulls which was 4800 rpm through 5700 rpm, and then was still making 649 lbs. at 6300. We didn't necessarily build it seeking peak horsepower numbers, but we tried to build a "safe" torque monster that can run all day. We believe we succeeded in doing that. Questions or comments?

It looks like you guys have been working your butts off. You better put some wings on that boat, because it looks like its going to fly away. Thanks for the flow numbers, I've been looking at aluminum heads and comparing all the numbers I can get my grubby mitts on.

I think this an awesome combo. Would this engine combo work as well in a drag car as it will in the boat?
Would the cam be compatible with a bracket car?
What are the details of the combo? I have a set of B heads very similar to your street/strip combo (currently damaged from a piston to valve mishap that took out most of the bottom end) and will be putting together a stroker one day when I can afford it. I like the combo you have put together, not too many revs so it will last.
I will be repairing the heads and getting them ported to race specs.

Engine Data

The cam was 270* - 278* @ .050" The lobe separation angle was 110* and it had a ground in 4* advance. So the intake lobe centerline was 106* and the exhaust was 114*. In open 29*, In close 67*, Ex open 73*, Ex close 25*. Lobe lift was .400" so it was .692" gross at the valve.

The compression ratio was a "safe" 10.25 to 1 with JE dished pistons on a 6.800" long Eagle rod. Bore was 4.605" and stroke was 4.300" using a cast steel Scat crank, Milodon pan and windage tray with just an external belt driven oil pump, not a dry sump. Timing was at 37 - 38*

We could have upped the compression ratio some and certainly made more power, but we really wanted to keep it safe for piss poor pump gas that came from Poldunk Hollow.

The single plane Victor SVO manifold had an 1150 cfm Dominator on it and the tunnel ram is one that Jet Boat Bob made himself. It had a pair of Quick Fuel reworked 1050 Dominators on it.

Yes, it would "work" in a drag car and be a safe dependable engine. There at one time the timing got accidentally bumped up to 46 degrees and the engine never pinged during a pull. (Always bring a spare timing light to your dyno sessions, so when you're high dollar light goes bad, you'll have a spare!)

I was thinking of upping the compression to about 13:1 and converting over to alcohol with my Pro Systems 1170. I have a Victor ported to the heads and custom headers.
How would that go with the rest of your combo? I really do like keeping the revs down so it will have a long life. I don't mind spending some money to get the right parts. What block did you use?

Answers to questions:

We used a Ford A-460 block. That will accept the big bore of 4.605".

As for how would your upgrade plans "fit" with the rest of our combo? Okay - BUT - you'll be exceeding the 850 Hp limit of the Scat cast steel (9000) crank. Therefore you'll need to upgrade the crankshaft to be able to safely handle the horsepower upgrades such as compression & etc. You will need a good forged crank or a billet for your intended application.

Charlie. I didn't see it or I missed it you are running a shorter stroke crank than 4.5. If so I would have thought the HP numbers would have come in at a little higher rpm? Or is it because the cam is 4 degrees advance? Or is it that T-ram with its long runners?

Good questions. Yes we are running a 4.300" stroke crankshaft with this pump gas deal.

Pull # 10 gave the following results with pump gas and 36.5 degrees timing.
I'm just giving the upper numbers:

5600 = 755 Hp
5700 = 758
5800 = 764
5900 = 771
6000 = 773
6100 = 770
6200 = 776
6300 = 779
6400 = 774
6500 = 772

6500 rpm was where we stopped the pulls. Last thing we did was throw some Torco 116 race gas in it. As Phillip said this was the wrong application, meaning 110 would have been good enough, but here are the results with the timing bumped to 38.5 degrees

5600 = 750 Hp
5700 = 759
5800 = 765
5900 = 771
6000 = 771
6100 = 773
6200 = 778
6300 = 780
6400 = 781
6500 = 781

So we see the engine peaked out just a little bit higher as you thought it might Bobby. Remember our objective was to build a safe pump gas engine that would be good for riding around and drinking beer and eating fried chicken. This engine has dished JE pistons and one thing Lem said was that; "This engine is just a set of flat tops and a roller cam way from being a good race engine!"

What Octane was the Pump gas? Do you think that the 110 would give more HP than the 116?

92 pump octane and yes.

What is the cut of at what compression would you go to the 116, or may be what is the most compression would run on the 110?

Torco 110 is good for 13/13.5 easy enough.

Here's some more BLUE THUNDER info with the Ford exhaust port

514, 13.93com., 40 degree timing, roller cam, victor w1300 cfm Pro Sytem carb.

7200 rpm 779.5 HP/ 616.2 TQ (peak of 7 pulls on Sunoco Supreme)

Heads 2.250 intake/ 1.880 exhaust on 4.5 bore @28"

.100 75 cfm 63 cfm
.200 142 113
.300 210 151
.400 275 184
.500 307 214
.600 341 239
.700 367 256
.800 380 270

How much more do you think a set of "a" heads would make on this engine?

The peak intake flow numbers would go from 380cfm to 450 cfm. That's 70 cfm at peak and should be around 100 Hp.

Exhaust Flow Test Results by Charlie Evans

Here's some data that I thought might be interesting to you.

#1. Bruce's new assembled Blue Thunder heads cam in here for some Pocket Porting. They already had a valve job done on them, and a set of no-name valves. I do not know who did the valve job, but that's besides the point. I always try to tell the guys that even though you may have new heads with a brand new valve job, it may not be good enough and I may have to redo the valve job.

Again his heads were new B.T.'s and they had the standard Ford exhaust port location, with the floor of the port filled and raised. Also you need to remember that these heads have a 1.880" exhaust valve.

His out of the box, baseline numbers were;

.100=65.5, .200=107, .300=144, .400=172, .500=189, .600=194.3, .700=193.7, .750=192.3 cfm.

After pocket porting we made some big gains at the high end of the spectrum, here are the numbers;

.100=61.5, .200=113.1 ,.300=147.5, .400=172.6, .500=193.6, .600=213.5, .700=228.4, .750=235.8 cfm.

I still wasn't satisfied and I called Bruce and told him we needed to redo the generic valve job that these exhausts had on them. So with no additional porting, just a change in valve job, here are the numbers;

.100=63, .200=112.4, .300=145, .400=173.8, .500=200.5, .600=225.3, .700=244.4, .750=252.4 cfm.

Now I'm all happy. We gained 7 cfm @ .500, 12 cfm @ .600, 16 cfm @ .700 and 17 cfm @ .750", just by redoing the valve job. Important things to remember are; 1. All my numbers are WITHOUT a flow test pipe. 2. These heads were POCKET PORTED, not fully ported. Although fully ported heads would have flowed more, pocket porting is the best bang for the buck. 3. The Blue Thunder heads have the valve centers spread and have a big 1.880" exhaust valve in them.

Please don't go comparing these flow numbers to a set of ported this, that and another type of heads and start bashing one set or the other. The point I'm trying to make is; that if a Mom and Pop machine shop have been doing good basic 3 angle valve jobs for 20 years, but they don't have a flow bench and/or are unwilling to do R&D in order to find out what makes a good competition valve job, you are leaving a lot of flow potential on the table by getting a generic valve job from them.


This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:29 PM

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Re: Cylinder Head Info

January 26 2010, 5:33 PM 

Aluminum Stock Layout Head Flow Numbers

Edelbrock Standard Port Head

Courtesy of Charlie Evans

2.19 x 1.75

Unported, out of the box with no test pipe on the exhaust:


Fully ported with Victor port match


TFS Street Head

Courtesy of Charlie Evans

2.20 x 1.75

Unported, out of the box with no test pipe on exhaust


Fully ported with Victor port match



Edelbrock RPM CJ Head

Courtesy of ScottJ

Out of the box

.100 - 82/64 78%
.200 - 156/110 70%
.300 - 225/155 68%
.400 - 279/182 65%
.500 - 323/200 61%
.600 - 341/214 62%
.700 - 347/212 61%
.800 - 350/212 60%

Stage 2 intake and exhaust port

.100 - 79/64 81%
.200 - 153/114 74%
.300 - 225/161 71%
.400 - 278/192 69%
.500 - 324/215 66%
.600 - 353/240 67%
.700 - 365/248 67%
.800 - 380/250 65%

Ford A429 Aluminum CJ Heads Flow Numbers

Courtesy of Brenden Howe

These are from my old style TFS CJ heads that Kaase did a few years ago.

2.25 Intake, 1.75 Exhaust


Courtesy of David S

2.25 Intake, 1.76 Exhaust

Lift=Valve lift while testing
Previous CFM = Original flow
Current CFM = Flow after porting % Gain=flow improvement in percent
Exhaust/Intake = Relationship between intake & exhaust flow

Intake Port Test Results

Lift Previous CFM Current CFM % Gain Exhaust/Intake Ratio

0.050 50.3 49.6 -1.4 69.0
0.100 88.2 82.3 -6.8 80.4
0.200 143.6 142.6 -0.7 85.5
0.300 199.1 202.0 1.5 87.1
0.400 254.0 264.4 4.1 76.2
0.500 291.2 317.1 8.9 72.6
0.600 308.2 348.4 13.0 72.6
0.650 317.1 361.8 14.1 70.7
0.700 321.6 370.7 15.3 69.0
0.750 321.6 379.7 18.3 67.4

Exhaust Port Test Results

Lift Previous CFM Current CFM % Gain Exhaust/Intake

0.050...40.6 34.2 -15.7 69.0
0.100...72.5 66.1 -8.8 80.4
0.200..115.5 122.8 5.6 85.4
0.300..158.9 176.0 10.8 87.1
0.400..166.4 201.6 21.2 76.2
0.500..188.8 230.4 22.0 72.6
0.600..193.6 252.8 30.6 72.6
0.650..195.2 256.0 31.1 70.7
0.700..195.2 256.0 31.1 69.0
0.750..195.2 256.0 31.1 67.4

Blue Thunder Heads With Chevy Exhaust Port

Courtesy of Charlie Evans

Out of the box - Unported - with a valve job

.100 - 67/60 89%
.200 - 129/114 88%
.300 - 188/148 78%
.400 - 251/176 70%
.500 - 301/194 64%
.600 - 322/207 64%
.700 - 331/215 64%
.750 - 335/219 65%

"Super" Bowl Work/Blending

.100 - 71/61 85%
.200 - 150/118 78%
.300 - 209/158 75%
.400 - 273/188 68%
.500 - 329/213 64%
.600 - 340/237 69%
.700 - 343/258 75%
.750 - 346/266 76%

Fully Ported Street/Strip

.100 - 72/67 93%
.200 - 148/122 82%
.300 - 213/163 76%
.400 - 277/191 68%
.500 - 331/215 64%
.600 - 351/241 68%
.700 - 356/265 74%
.750 - 359/276 76%

Fully Race Ported

.100 - 73/67 91%
.200 - 152/122 80%
.300 - 216/163 75%
.400 - 281/198 70%
.500 - 335/227 67%
.600 - 363/251 69%
.700 - 377/271 71%
.750 - 380/280 73%

Courtesy of ???

Done by Todd Macinzie who worked for Ken Duttweiler with decent clean-up. No exhaust tube.

Intake Exhaust

This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:34 PM

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Re: Cylinder Head Info

January 26 2010, 5:36 PM 

Aluminum Stock Modified Layout Heads


Ford Aluminum SCJ Heads

Aluminum SCJ flow numbers from Team 385 Build in 2003

Courtesy of ScottJ

Cylinder head castings SCJ-B. Jon Kaase's "Super Cobra Jet" castings ported Stage 3 and bench tested by yours truly at RHP. 315 cc intake ports and 110 cc exhaust ports. Expected flow rates are 385 cfm @ .800" intake and 250 cfm @ .800" exhaust. The valve sizes are the as delivered 2.2" /1.76".

Here are the preliminary flow numbers for the SCJ's as cast...


Final flow numbers were...


A cross check with Daves bench showed 370 cfm max intake and 250 max exhaust. The exhaust figures were 275 cfm with pipe. My bench is a bit optimistic intake and conservative exhaust flow wise. The intakes peaked at 390 CFM at .560" lift. The port began to get rough at .600" lift when the short turn was more square. Laying back the short turn helped the high lift numbers by reducing break away but mid lift numbers began to fall off. The castings were ported differently one to focus on high lift numbers and the other for mid lift flow.

The SCJ head rocks as delivered and is a great street head especially on a 500 inch or bigger combo. I feel that the smaller intake port cross section of the RPM head would be better on the smaller displacement engine providing better average numbers.

Ford Kaase SCJ Info

Courtesy of Charlie Evans

Ford Kaase SCJ Flow Numbers

Out of Box;

Intakes; .100=73, .200=167, .300=250, .400=318, .500=340, .600=328, .700=328 cfm

Exhaust; .100=57, .200=102, .300=144, .400=175, .500=186, .600=196, .700=202 cfm

SuperBowl Blend;

Intakes; .100=73, .200=167, .300=252, .400=323, .500=371, .600=349, .700=344 cfm

Exhaust: .100=58, .200=103, .300=145, .400=177, .500=190, .600=207, .700=218 cfm

Fully Ported;

Intakes; .100=72, .200=154, .300=252, .400=336, .500=393, .550=401 .600=366, .700=362, .750=360 cfm

Exhaust; .100=61, .200=114, .300=157, .400=185, .500=204, .600=225, .700=233, .750=234 cfm

Exhausts were flowed WITHOUT a test pipe.

The above flow data was with Ford valves M-6507-B429 intakes and M-6505-A429 exhausts.

Testing With Different Valves

Our next test was to try different valves. We tried 4 different intake valves. The Ford valve and a Ferrea #F1228P were both 2.200". With a proper backcut of 30* and about .080" wide, we got basically identical flow numbers. These are the ones I've given in the other post for intake flow. Next we had a couple of 2.250" valves. I had a S-I #1652SG + 100 and a REV # CL1742. The REV was better than the S-I and here are the intake flow numbers with the 2.250" REV.

Intakes; .100=70, .200-154, .300=253, .400=335, .500=392 (that's right), .600=363, .700=356, .750=356 cfm @ 28" H2O. Notice that the intake flow was hurt some below .400 as compared to the smaller 2.200" valve, but that the intake flow gained some at .500 and above.

Exhausts; Five different exhaust valves were tried. They are the Ford M-6505-A429 which is very much a tulip shaped exhaust, and a REV CL 1832, a S-I 6005 SG these are both 1.77 Pontiac valves. Also a REV 1.800" #1834 and a custom Manley titanium valve that is 1.75". Thus far the Ford valve is the "winner" and the Manley custom titanium is in second place. I think it will be hard to beat the Ford exhaust valve, but still more testing will be done.

Data For Valve Length, Tip Length And Installed Height

Lem and I spent some time this afternoon mocking up and checking about nine different brands and lengths of valves in the SCJ heads. I'll try to give it to you.

Intake valves

1. 2.250" REV #CL1742 1.975" installed height with standard keepers,
5.375" long w/.250" tip.

2. 2.200" Ford M-6507-B-429 1.893" installed height with standard keepers, 5.265" long w/.250" tip.

3. 2.250" S-I #1652SG 1.888" installed height with standard keepers,
5.285" long w/.260" tip.

4. 2.200" Ferrea #F6196 1.888" installed height with standard keepers,
5.271" long w/.250" tip.

Exhaust valves

1. 1.770" S-I #6005SG 2.081" installed height with standard keepers,
5.210" long w/.220" tip.

2. 1.770" REV #HP4004 2.045" installed height with standard keepers,
5.220" long w/.250" tip.

3. 1.800" REV #CL1834 1.965" installed height with standard keepers,
5.155" long w/.250" tip.

4. 1.760" Ford M-6505-A-429 1.935" installed height with standard keepers, 5.060" long w/.260" tip.

5. 1.760" Ferrea #F6258 1.876" installed height with standard keepers,
5.055" long w/.250" tip.

Valve Train Geometry

Courtesy of Randy Malik

The SCJ geometry is good with "stock" length valves. Problems with the geometry can develop on the intake side when "longer" valves are installed. The P-51 head's rocker geometry was changed slightly and ".100" longer" valves are intended to be used with that head.

This message has been edited by DJOHAGIN from IP address on Jan 26, 2010 5:38 PM

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