My home inspection of Speedmaster heads
- Thread starter 318willrun
- Start date
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As best as I can tell, the versions with CNC chambers is only available in a bare head.
Seat pictures attached, someone with more knowledge than me can comment on them.
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PRH
Well-Known Member
Seats look just like the unported ones I had here.
The porting option for that head during the last sale was a smoking deal.
The porting option for that head during the last sale was a smoking deal.
lead69
hopeless car junkie
I couldn't help it, by now I would have been going at them with a cartridge roll!
Need to finish talking them apart, do my dimensional checks first, but then I'll clean up there little bit that needs it before they go off for flow and valve job.
A side note here, I'm still ahead of the game vs trick flows, but for anyone who doesn't plan to run them out of the box, the deal is much closer than the sale price would indicate.
Shipping both ways to PRH, valve job, valve seals, and the b3 kit, all of which should be unneeded with the TF heads, all of it adds up.
lead69
hopeless car junkie
I agree it adds up quick. I looked at all the ways to make the hp I wanted to make but when the trickflows finally came out and I could get them for $1800 to my door I hit the easy button.
Now I have some bare speedmaster heads sitting on the shelf as well and cannot decide if I want to break out the grinder or not, (I actually do but I am fighting the temptation lol) we shall see.
How big of a cam are you planning to run Turbo.
Now that's the question isn't it.
For the sake of getting things running for the spring (I'm installing a pro flo 4 and and all new fuel system as well this winter) I'm going to keep the Comp 305H that's currently in the car.
I'm sitting on a new set of Johnson mech roller lifters, so next I'm hoping to have pick out a new cam and install it/springs next winter.
I’ll have to check those cam specs out as I’m not familiar with it. I take it the Pro Flow 4 is injection.
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Ok since I no longer have access to a ProMaxx Head I went back to my pictures that I posted in my Edelbrock to ProMaxx comparison post. Hard to really tell from pictures but it looks like the ProMaxx heads had a 3 angle valve job compared to a two for Speedmaster. Not sure way they would cut a cost corner there because there is zero labor costs involved in the two. ProMaxx heads also have some cfm gaining attention to detail in the valve seat installation as it looks like the were flapper wheel sanded and cleaned up a lot nicer after being pressed in. Athe shortside was nicely blended instead of stepped. If I were a betting man these will be in the 248-258 cfm area max. The valve job sucks but I’m still sticking with it will flow better than an Edelbrock
gzig5
Well-Known Member
What does a stock Edelbrock SBM flow on your bench before you violate it with the burr?
yellow rose
Overnight Sensation
If you polish out those spots in the picture you'll be making the port bigger than it already is. Are you sure it wants to be bigger there?
Not sure about anything yet. Plan is to check the cross section of the clean port with a snap gauge and compare vs the ones with some as cast surface.
I'm smart enough to know what I don't know, so feel free to give me any feedback. I planned mostly a light polish vs any real material removal.
lead69
hopeless car junkie
I'm not sure if it's core shift or the ports just aren't truly 190 but either way you are smart to measure them. Just by looking at it I would think it could go a touch bigger by cleaning up the cnc work throughout the entire port and the step at the bowl and be more uniform/pickup some flow. But what the hell do I know lol, YR,PBR,PRH???
Just keep in mind that cnc ridges won’t bother a thing and may help. When I port my own heads it’s a double flute burr finish on every intake side. I would take a semi rough sanding roll to customers ports because people like smooth.
yellow rose
Overnight Sensation
You have two options as to why you have bald spots in a port.
Tool defection or the casting is big there already.
yellow rose
Overnight Sensation
This time I'm going to spend some time with surface finish. I'm with the crowd that says when the airspeed is high, you polish the surface and when it's slow (or not there at all) you burr finish. Or use a 40 grit paper roll.
It's been so long since I've done some W2 heads I can't remember if the center exhaust ports have air going in both directions at the same time at .200-.400 or so lift numbers. I know a bunch of bow tie exhaust ports will do it. Can't remember if the W2 does it or not.
Heads are going to work with me on Monday to check guide dimensions and clearance, I'll take some measurements at the spots we're discussing and post my findings.
PRH
Well-Known Member
Prettying up the drop outs left from CNC porting is one of those tried and true DIY operations.
No....... it won’t make the car go any faster, but it makes the owner feel better when the whole port is shiny.
I’ve done it to new cnc ported heads that I’ve sold...... but solely to ward off those “hey, what about those parts that got missed during porting” questions.
I’d just run a burr over that area to shine it up a little.
No....... it won’t make the car go any faster, but it makes the owner feel better when the whole port is shiny.
I’ve done it to new cnc ported heads that I’ve sold...... but solely to ward off those “hey, what about those parts that got missed during porting” questions.
I’d just run a burr over that area to shine it up a little.
lead69
hopeless car junkie
I guess my question was are they really 190 ports?. If you look at the flow numbers posted they are not great for being a 190 port, I realize other things can affect that but it seems possible they are smallish in size. When compared to a trickflow they seem to have allot of unfinished area as mentioned and I agree they could be big already in those areas due to the castings, really the only way to know for sure is to cc one. As far as the cnc work I was simply thinking of making the port bigger if needed not so much the finish.
It seems there are two schools of thought on surface finish depending on the application but I only have second hand knowledge of it and have no actual testing to back up either. I have for the most part left my intake ports carbide rough and semi polished the exhaust but I use a an electric die grinder with allot of speed and the ports are pretty smooth as finished. YR has chastised me for it a few times but I don't like messing with air any more!.
It seems there are two schools of thought on surface finish depending on the application but I only have second hand knowledge of it and have no actual testing to back up either. I have for the most part left my intake ports carbide rough and semi polished the exhaust but I use a an electric die grinder with allot of speed and the ports are pretty smooth as finished. YR has chastised me for it a few times but I don't like messing with air any more!.
PRH
Well-Known Member
Cc-ing a runner or two is a good idea.
The BB cnc “325” I checked was 301cc.
The BB cnc “325” I checked was 301cc.
Took some time to pin gauge the guides and mic the valve stems. Everything was very consistent, and looks good.
All guides were 0.3422-.3431 (0.342 on my + size pin gauge fit, .343 doesn't)
Measured all valves in four places, top and bottom, 90deg offset from each other (12/6 and 3/9) to check for taper and out of round (egg shaped)
All valves were round and straight within .0002, max measurements for each listed below
Intake:
0.3403
0.3405
0.3404
0.3406
Exhaust:
0.3406
0.3408
0.3404
0.3405
All guides were 0.3422-.3431 (0.342 on my + size pin gauge fit, .343 doesn't)
Measured all valves in four places, top and bottom, 90deg offset from each other (12/6 and 3/9) to check for taper and out of round (egg shaped)
All valves were round and straight within .0002, max measurements for each listed below
Intake:
0.3403
0.3405
0.3404
0.3406
Exhaust:
0.3406
0.3408
0.3404
0.3405
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