[Skip Fix]

Superflow 110 calibrated using the "pass around" 300@28 and 350@28" plate. Small bench would not pull even the normal 10" at the 300 so we ran it at 5" and used the Superflow conversion chart to get to 28" for comparison . Temp was about 75 and 50% humidity. Some folks will say different numbers using smaller pressure but with 5 of the "pass around plates" it is right on -even after being moved! Clay around intake port to smooth entry no "pipe" on exhaust. No velocity probe Stan. I assumed turbulence at the higher numbers as it made a definite sounds change.

Heads are with their valve job-which is not great. An Autolite 3924 spark plug was perfect fit no excessive threads sticking out.

0.200 Intake 139, Exhaust , 83%

0.300 Intake 209 Exhaust 162, 77%

0.400 Intake 269 Exhaust 190, 70%

0.500 Intake 292-sounded like some turbulence, Exhaust 209, 71%

0.600 Intake 302 turbulence, Exhaust 222, 73%

0.700 Intake 304 turbulence,Exhaust 222, 73%

[Stan Weiss]

Skip,
Thanks for that great information. Did you happen to cc the intake port?

What size bore did you use?

Stan

[Skip Fix]

No cc yet on port or chamber. Bore choice was 4.20 or 4.0 so we used the 4.2 ". Calibration plate straight on bench no adapter.

Figure the KRE or SD CNC heads with a 2.350 entrance are listed as 310-320cfm but I have never verified one on a bench. I knoe KRE used to use a non Superflow I think laminar bench.

[PAUL K]

Thanks Skip... I think your numbers show why there is a lack of flow information for these heads. Until the SM heads I've never seen anyone selling CNC ported heads without providing some type of flow numbers.

[mgarblik]

Appreciate you running those heads on your flow bench. Have to admit a little surprised to see a CNC ported "modern" aluminum head essentially stall at .500 lift and go into tumble/turbulence. Basically, that head as you tested it is done at .550 valve lift. I also find it interesting that a stock Ram Air V I had on my flow bench never went into tumble and continued flowing more and more air until the retainer hit the valve guide at about .950 lift. Guess that big obstructive tube in the intake port wasn't as much of a detriment as a not so great design regular port. Love the flow bench to separate fact from fantasy. Now if there was just a way to translate flow bench results to on track performance! But it's not that simple. Appears the Speedmaster head is a small upgrade from a mildly worked over set of iron heads. At Black Friday prices, a decent option I guess on a large displacement engine. Curious, anyone have "as cast" flow numbers for these heads? The CNC version can't be more than 10% better?

[Murf]

I don’t know anything about flow testing heads. I hung around when the porter flowed my iron heads after porting. I have heard the sound change as they go into turbulence. At least, I think I have. ��
So now for my question
Is it normal for flow to keep increasing when the port is experiencing turbulence? I was surprised to see that happening in Skip’s test. If the flow doesn’t fall off dramatically, what is the main detrimental effect of the turbulence? Is it fuel falling out of suspension or what?

Thanks guys!
Murf

[grivera]

Originally Posted by mgarblik

Appreciate you running those heads on your flow bench. Have to admit a little surprised to see a CNC ported "modern" aluminum head essentially stall at .500 lift and go into tumble/turbulence. Basically, that head as you tested it is done at .550 valve lift. I also find it interesting that a stock Ram Air V I had on my flow bench never went into tumble and continued flowing more and more air until the retainer hit the valve guide at about .950 lift. Guess that big obstructive tube in the intake port wasn't as much of a detriment as a not so great design regular port. Love the flow bench to separate fact from fantasy. Now if there was just a way to translate flow bench results to on track performance! But it's not that simple. Appears the Speedmaster head is a small upgrade from a mildly worked over set of iron heads. At Black Friday prices, a decent option I guess on a large displacement engine. Curious, anyone have "as cast" flow numbers for these heads? The CNC version can't be more than 10% better?

Flow Numbers from Randy Repp: http://forums.maxperformanceinc.com/...0&postcount=16

Full thread: http://forums.maxperformanceinc.com/...ht=speedmaster

[Skip Fix]

I think from feeling the short turn it is smooth but could be "laid back" a little more into the floor of the port and probably do a little better. We'll see what a better valve job and a back cut on the valve does. Port entrance and common wall into short turn and pocket are where most of the CNC work was.

[PAUL K]

Originally Posted by PAUL K

Thanks Skip... I think your numbers show why there is a lack of flow information for these heads. Until the SM heads I've never seen anyone selling CNC ported heads without providing some type of flow numbers.

I stand corrected..... Forgot Fluper sold his AFR CNC heads without flow numbers.... But they actually weren't CNC ported so maybe that doesn't count.

[PAUL K]

Originally Posted by mgarblik

Appreciate you running those heads on your flow bench. Have to admit a little surprised to see a CNC ported "modern" aluminum head essentially stall at .500 lift and go into tumble/turbulence. Basically, that head as you tested it is done at .550 valve lift. I also find it interesting that a stock Ram Air V I had on my flow bench never went into tumble and continued flowing more and more air until the retainer hit the valve guide at about .950 lift. Guess that big obstructive tube in the intake port wasn't as much of a detriment as a not so great design regular port. Love the flow bench to separate fact from fantasy. Now if there was just a way to translate flow bench results to on track performance! But it's not that simple. Appears the Speedmaster head is a small upgrade from a mildly worked over set of iron heads. At Black Friday prices, a decent option I guess on a large displacement engine. Curious, anyone have "as cast" flow numbers for these heads? The CNC version can't be more than 10% better?

Did the RAIV head keep gaining flow? There is a big difference from the original RAIV heads and the over the counter SR heads. One usually levels out but stays steady, the other usually takes a nose dive around .500. I've been able to study and port many sets of 614's. Unfortunately I have less experience with the 722's. Most of the 722's we worked on were done earlier, before the Edelbrock heads. Back then we were just concerned with improving flow. I went through a pair of virgin heads (722) for a 69 TA a couple years ago. We did flow them, but barely found the time to do that, let alone start mapping them out. I recall those peaked around .500 and leveled out.

[mgarblik]

Originally Posted by PAUL K

Did the RAIV head keep gaining flow? There is a big difference from the original RAIV heads and the over the counter SR heads. One usually levels out but stays steady, the other usually takes a nose dive around .500. I've been able to study and port many sets of 614's. Unfortunately I have less experience with the 722's. Most of the 722's we worked on were done earlier, before the Edelbrock heads. Back then we were just concerned with improving flow. I went through a pair of virgin heads (722) for a 69 TA a couple years ago. We did flow them, but barely found the time to do that, let alone start mapping them out. I recall those peaked around .500 and leveled out.

Sorry Paul. I should not have confused this thread with a Ram Air V comment. I could not go back and remove it. Just comparing the Tunnel port head with the giant restrictive tube in the middle of the port to the CNC Speedmaster. Apples to oranges really, carry on.

[mgarblik]

Thanks for the specs. non-CNC Ported. so here is the comparison:

lift INTAKE Stock INTAKE CNC EXHAUST STOCK EXHAUST CNC

.200 147 139 124 139
.300 213 209 156 162
.400 258 269 177 190
.500 269 292 195 209
.600 289 302 202 222

So there is a gain, nothing dramatic. With the right camshaft, there is likely some HP with the CNC port. A lazy, stock style slow opening camshaft won't gain you much of anything IMO. A fast opening cam that can get you to .300 lift quickly and stay in the .300-.550 zone a long time would be the ticket with these heads as presented. Probably be pretty rough on the valve train. Like everything, always a compromise. Low intake lift flow is pretty weak with the CNC version. Exhaust side is much better. Wonder if they would just do the exhaust side and leave the intake alone? That combination would improve the intake/exhaust ratio and let you play with the cam design more. Interesting stuff.

[Jay S]

The picture on the previous thread about the CNC speedmaster’s showed most all the CNC work was on the ceiling, and little to nothing on the floor or short turn, with very little work in the bowl. I thought there was a good chance that was going to make the flow stall pretty early. Stalling at .5” surprises me a bit, but I guess it shouldn’t, that is what has happened nearly every time I have done something similar were the work is concentrated only on the ceiling, making the port bigger.

Probably the only way you can really fix that is to turn the air sooner into the short side radius and install some bigger valves. That or epoxy the ceiling and work on the short side so the CSA of the throat can move more air, without loosing velocity.

At least the exhaust port cnc work had some improvement. They would have been better off leaving the intake port stock and only having the CNC work done on the exhaust side. They made a mess on the intake.

[PAUL K]

Originally Posted by mgarblik

Sorry Paul. I should not have confused this thread with a Ram Air V comment. I could not go back and remove it. Just comparing the Tunnel port head with the giant restrictive tube in the middle of the port to the CNC Speedmaster. Apples to oranges really, carry on.

That's makes sense but thought it might be of interest to compare the characteristics of the RAIV heads and the SM. After all the SM is a copy of the aluminum RAIV replacement head.. When I have a chance I was going to post a thread in regards to the differences between the Service RAIV heads and the OEM. I misread your post that it was a RA V head you flowed.... Yes those will continue to flow forever.

[PAUL K]

Originally Posted by Jay S

The picture on the previous thread about the CNC speedmaster’s showed most all the CNC work was on the ceiling, and little to nothing on the floor or short turn, with very little work in the bowl. I thought there was a good chance that was going to make the flow stall pretty early. Stalling at .5” surprises me a bit, but I guess it shouldn’t, that is what has happened nearly every time I have done something similar were the work is concentrated only on the ceiling, making the port bigger.

Probably the only way you can really fix that is to turn the air sooner into the short side radius and install some bigger valves. That or epoxy the ceiling and work on the short side so the CSA of the throat can move more air, without loosing velocity.

At least the exhaust port cnc work had some improvement. They would have been better off leaving the intake port stock and only having the CNC work done on the exhaust side. They made a mess on the intake.

I'm guessing they copied a commercially ported head and had to back off in the bowl area because of the issues in their bowl..... I'm thinking the non ported casting with just a basic clean up would make for a better head.

[mgarblik]

Originally Posted by PAUL K

I'm guessing they copied a commercially ported head and had to back off in the bowl area because of the issues in their bowl..... I'm thinking the non ported casting with just a basic clean up would make for a better head.

I agree with you. No idea what they charge for the CNC work. But spending a little time by hand working the short turn a little, minor bowl work, and a better valve job would probably give you a better finished head. The exhaust program is far better than the intake as mentioned.

[Skip Fix]

Jay there is CNC work on floor and short turn you can feel, just hard to get a picture.

[Skip Fix]

Shot turn hard to get focused

[Jay S]

Originally Posted by Skip Fix

Shot turn hard to get focused

Thanks Skip. That was a good photo. It appears they turned the short turn way to sharply. Then made it even more of an issue making the top of port bigger. I think that short turn should have been pulled back and started the turn sooner. Looks like there is room too do that? Maybe Paul will say otherwise. I recall it the sides closer too the wall and btw the valves where those heads are lacking the material to hold the seats in?

[Skip Fix]

I think that short turn should have been pulled back and started the turn sooner

I agree.

Seats have plenty of material around them.