Speedmaster Small block porting tips and results Part 1

[Cudafever]

just to help a little
these are PBR out of the box####

I finally bolted one of my heads down on the flowbench today and got some numbers. I bought mine bare so these numbers are with one used Edelbrock exhaust valve and one used 2.02 Edelbrock intake valve with a 30 degree backcut added. Other than that as out of box

.100——55
.200——131
.300——185
.400——-235
.450——-247
.500——-240. Numbers backing up
.600——-246
.700——-256-262 turbulence
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and these are afterwards.


.100———-68 cfm
.200———-142
.300———-198
.400———-244
.500———-252
.600———-262
.700———-262
.750———-258

UPDATED

just to help a little
these are PBR out of the box####

I finally bolted one of my heads down on the flowbench today and got some numbers. I bought mine bare so these numbers are with one used Edelbrock exhaust valve and one used 2.02 Edelbrock intake valve with a 30 degree backcut added. Other than that as out of box

.100——55
.200——131
.300——185
.400——-235
.450——-247
.500——-240. Numbers backing up
.600——-246
.700——-256-262 turbulence

After that test I added a 30 degree and 15 degree cut to the factory 60 and 30 seat cuts from the factory. I then widened the .930 measurement at the pushrod pinch to the 1.015 measurements given to me from the cnc’d heads from Speedmaster. I then removed the slight overhang right before the seat on the shortside. I then took a 40 grit sanding roll to the whole port and mounted it for my second flow test. Before and after number side by side.
Before—————-after
.100——55——————65
.200——131—————137
.300——185—————-194
.400——235—————-240
.450——247
.500——240—————250
.600——246—————265
.700——256-262———263

ok between a late night last night, bad right side pain again, and getting up for Church I had a bad case of dragging butt today. I watched the first possession of the Steelers and I could read the writing on the wall so I took a nap, watched the news, and hit the shop. I saw on the flowbench what I expected for the work I did and not reshaping the shortside. Just because a head CAN flow more air doesn’t mean it will. I’ll post the numbers and while I eat if you want to take a guess what happened please post up. Then I will show you why.

.100———-68 cfm
.200———-142
.300———-198
.400———-244
.500———-252
.600———-262
.700———-262
.750———-258

 

[Cudafever]

There now you can see how vary little improvement between the seat cut and his last cut.

 

[Cudafever]

One more thing and then i'm going to shut up.
For most people, messing with the ssr will only get you into trouble. Clean casting flaws, and live with what you have.
There is a million reason why and i will give you just one.

You can see the ssr from the valve side.......
You can see it also from the port side......... But the "Taint" you can not.
Taint? the part that you can not see with your eye or see the bur with you eyes and have to feel your your way around to get it consistent, let alone the right shape.
You had better be vary comfortable with your grinder making smooth shapes in the port before you ever attempt to shape the ssr.

 

[MOPAROFFICIAL]

Anytime you unshroud the intake valve at the chamber, you open the flood gates to the common wall. Either do it first and work with it, or do it in very small increments to get where you're going. The turn isnt worked yet , we know that much, but it's ootb better than a factory production head and imo shouldn't take much laying back.

This port PBR is working on has gone into what's called 'saturation' for .100 lift then drops a few cfm... That's telling you the ssr needs work.
What's the cross section at the throat in front of the valve guide, is it bigger than 1.625?
You get that 10-15 cfm by unshrouding, but you know its work after that. And depending on the head.. well ,that's why it costs. The jump from 400-600 to 1000 starts there.

 

[PRH]

You have the port working and the short turn as is can't handle the extra speed and or flow? If that's what's happening then I think for a lot of us that's where the magic happens. Finding that extra up top without losing the low to mid. As I have discovered that's not something the average Joe pulls off.

You guys nailed it. Like I said airspeed can kill a port and a good ear will hear it before we see it. That dog gone air will shoot the shortside and crash the back of the bowl. This re-enforces that for the average guy buying a set of Speedmaster heads and you want 15-20 horsepower a simple buff and shine to remove bad casting spots and a valve job and you are good to go.

In a nutshell....... what he did for the first few steps...... that’s where the good “bang for the buck” ends.

 

[318willrun]

This is why, for the average Joe without a bench flow and factory cast heads, I suggest to work the bowl under the seat, remove casting burrs, and work the push rod area and remove the valve cover bolt hump on the intake side. Mild porting, modest gains, and really can't go wrong.

 

[gzig5]

The turn isnt worked yet , we know that much, but it's ootb better than a factory production head and imo shouldn't take much laying back.

Any chance you can edit 318willrun's drawing to illustrate the "laying back"? Having a hard time envisioning what would be happening there.
My intuition is that you would want to start that turn on the short side earlier in order to give the air more time/distance to get around the corner. The shape of the radius would be important too. That would mean moving the beginning of the curve towards the entrance of the intake port, but there is usually water under there and you can only go so far. Am I even in the ball park?

 

[pittsburghracer]

My point was to show how nice a port can look but give you a kick in the nuts on a Flowbench. Lots of sleepless nights and ruined heads cutting down the shortside in search of area.(the wrong move) 280-285 is what I expect to see before I’m done with a 2.02 valve. On topic that hasn’t been touched on much and I would like to hear more on is throat sizing. I think it was 318 that gave me his throat sizing on his cnc’d heads and it was a lot bigger than my bare heads. Did anyone else do anymore checking on this. I may flow the stock exhaust if I get some shop time today but it’s a total waste of time. The exhaust port is just plain ugly out of the box.

 

[12swinger]

I used to rough in heads for a reputable race engine builder. He’d never let me do the short turn.
I was showed where on the roof, outside wall, etc.. He did the short turn and chamber work normally.
There pretty secretive about some areas, plus it’s pretty easy to screw up the short side.
What used to blow me away was all the work involved to get a 906 head flowing 290cfm maybe 300 max wedge window, raised roof, blowing through the roof of everyone of them, and epoxy it. Done.
Now their is a ton of aftermarket choices.

 

[PRH]

I have some cnc heads here.
The throat is flat out too big for the 2.02 valve at 1.890(93.5%).
That’s a big part of why the mid-lift numbers with those heads aren’t great(frankly, with the ootb vj the low/mid-lift numbers are rather poor. The intake port doesn’t wake up til about .600 lift).

They cnc the bowl right to the 45.

 

[318willrun]

I think it was 318 that gave me his throat sizing on his cnc’d heads and it was a lot bigger than my bare heads. .

I have some cnc heads here.
The throat is flat out too big for the 2.02 valve at 1.890(93.5%).
That’s a big part of why the mid-lift numbers with those heads aren’t great(frankly, with the ootb vj the low/mid-lift numbers are rather poor).

They cnc the bowl right to the 45.

View attachment 1715445145

My heads were not CNC'd. I bought the regular SM heads fully loaded. I think the bowl and throat are big for 2.02's as they are, so I agree with PRH that the CNC ported heads would be best with larger valves and better valve job

 

[pittsburghracer]

This is off topic some but this used to be my favorite post to check into at least once a week. Photobucket really ruined it with how they make your pictures fuzzy if you don'y pay for their service but it still has some good tech. Take a rainy day and check it out.

Cylinder Head Show and Tell

 

[MOPAROFFICIAL]

280-285 is what I expect to see before I’m done with a 2.02 valve. On topic that hasn’t been touched on much and I would like to hear more on is throat sizing.

That's what I asked you.
A couple things I asked but never heard back on. But I know you're busy , no worries.
What size is it now?
You can see [email protected] & 260's @.500 that stick around..with a 1.625 throat width in production heads. Ime.
So im curious to know.

 

[PRH]

I think he said the throat diameter for the unported head was 1.830.

 

[MOPAROFFICIAL]

In a nutshell....... what he did for the first few steps...... that’s where the good “bang for the buck” ends.

As I’ve mentioned in other threads........ getting these into the 260cfm range, at a reasonable/usable lift...... should be pretty straightforward.
Recut the seats, blend bowls, back cut valves.

That’s where the cheap n easy gains end.

My attempt at the next step up from there, which would strictly be aimed at improving the numbers through .500-.550 lift or so, and might even cost a cfm or two at the top end(for the same reason that PBR had his last test do it)...... I’d go to the 2.055 intake valve(I’d buy bare heads if this was the plan from the beginning).
In all likelyhood though, even that change would probably require a bit of short turn work to make it worthwhile.

My goal would be to get into that 260 range with even less actual grinding than PBR did.
No(or at least less)work at the pinch and bolt boss..... and hardly anything in the bowl....... and little to no sanding.
I’d be relying on the bigger valve to relieve me from more grinding.

If you would have said this at the beginning, it wouldn't come off funny, to me at least.
Im getting the ..Watch it till the end and then be critical... vibe. I ,like others, are fine watching without jumping from the front row onto the stage to "show'em how to do it", he already knows and has done a good job not eluding to his ability for almost the entire time I've been on the board. Humble. This guy is good. I dont do a lot of sharing as often as I'd like... because of critical replies or replies that just crowd the stage...so when I get that vibe in this guys thread in the replies I'm reading...it pokes a nerve.
The author can say that at the end if he feels the same way...as well as the intelligent people of this board...can come to their own conclusions.
That aside..besides j par... there are 3 other posts that come off spoken from a mountain top...cracking me up. Same ones who dont wanna give it away... but cant let anyone have their show without an attempt to 'show up'. Take this as ball busting, cause it is. Start your own thread on them so we can tell the end before you get there. Right? lol

 

[MOPAROFFICIAL]

I think he said the throat diameter for the unported head was 1.830.

Interesting. Thanks

 

[yellow rose]

If you would have said this at the beginning, it come off funny.
Im getting the ..Watch it till the end and then be critical... vibe. I like others are fine watching without jumping from the front row onto the stage to show'em how to do it, he already knows and has done a good job not eluding to his ability for almost the entire time I've been on the board. Humble. This guy is good. I dont do a lot of sharing often as I'd like because of that kind of post.
The author can say that at the end if he feels the same way...as would the intelligent people of this board...can come to their own conclusions.
That aside..besides j pars there are 3 other posts that come off spoken from a mountain top...cracking me up. Dont wanna give it away but cant let anyone have their show without an attempt to 'show up'. Take this as ball busting, cause it is. Start your own thread on them so we can tell the end before you get there. Right?

No reason to say much when PBR is nailing it. That's why I said it's time to sit back and listen (read what he's doing) because he is giving a lesson most guys can't afford to pay for.

Take notes.

 

[PRH]

The author can say that at the end if he feels the same way..

He did say it....... and I quoted it..... then just reiterated/expanded on it.

I’m not being critical at all.
I’ve already stated that he’s gotten more out of those style heads than I have.

 

[MOPAROFFICIAL]

He did say it....... and I quoted it..... then just reiterated/expanded on it.

I’m not being critical at all.
I’ve already stated that he’s gotten more out of those style heads than I have.

I respect what you can do as well, just want to read it from the author.
I think... or I'd like to hope...there is mutual respect between the cyl head porters on here... but then.. too many times I read 'translated to'.. "my bench is better" "i would have done this better" "or that different" or "id have used another head". I believe you get what I'm saying. I'm not laying all that on you, just tired of seeing any of it. Sideways threads and backseat drivers...burn'em.
If more **** was phrased as a question.. it would really help the respect level go up. That's for sure.
You give the person a chance to answer for themselves. I can read and look and have it figured out too sometimes... but it's not my thread or experiment.
I dont give cookies for ADD episodes where someone talks over the speaker and finishes his every sentence before he does.
Now I've used up all my time in this thread.
Thanks for sharing.

 

[PRH]

Perhaps what I post comes across differently than how it’s intended.
From my perspective, I’m just trying to add to the conversation.

If PBR takes any offense to what I said in any part of this..... his.....thread...... I’ll happily delete the offending posts.
He can just PM me to keep it out of public view.
No hard feelings whatsoever.

 

[pittsburghracer]

First off this is OUR post. There is this one guy that goes off-track once in awhile but like I said we all do. I gotta go back and reread a few posts because yesterday between Church (1.5 hours) showering, driving to Church, eating, football, and a nap yesterday, I kinda got behind. That Jpar guy can post rather quickly at times. I will try to fill in some gaps. Lol. Early Happy New Year to all. I gotta run out to get my pork, kelby, sauerkraut, and cat supplies. Like Arnold always says. I’ll be back.

 

[IQ52]

I had to dig pretty far back in my notes.
There can be a noticeable spread between the 4 ports on these heads. I usually test the #1 cylinder.
It’s been a while since I flowed an ootb E head(60779).....
4.00 bore, no tube on ex:

Lift———in/ex
.100—— 64/49
.200——126/97
.300——185/133
.400——227/156
.500——250/166

Same here, I had to go many years back for my flows on a 60779. These were OOTB used heads that came in for porting.

.100.....61/53
.200.....126/106
.300.....175/142
.400.....223/157
.500.....248/165

This is a heck of a nice thread by PBR!

 

[IQ52]

I started porting heads before I worked at a shop, or had a flow bench...... based on what I was reading in magazines at the time.

I was always pretty good at avoiding mishaps when putting stuff together, but really didn’t “know” anything about what it took to make power or go fast.
For the most part I copied what others with more experience were doing.
I felt my car ran pretty good for what it was....... especially when I look back at how little I really knew about what I was doing.

PBR has a few years on me, was in an area where there was way more car stuff going on, and probably got an earlier start on it than I did.
I think some of his stuff from the 80’s ran real well considering how much harder information was to come by back then.

In about ‘85, I had my street/strip Satellite running 11.50’s in full street trim, minus an exhaust system.
It also had slicks.
But, no fresh air, no “fuel system”, battery still up front, full interior, heater, wipers.
There weren’t many cars like that running those times at my local track back then.

That motor had some 906’s on it that I reworked using info and looking at pictures from a build in a Car Craft magazine that had come out about a year earlier.

The point being....... someone who has the desire to “improve” their own SM heads should certainly be able to go through a thread like this and gather enough info to do just that.
No machine shop or flow bench required.

Man, my dad learned porting from an old guy that smoked, and his 'flow bench' was cigarette smoke that he blew into the port.

Dad never smoked so he was under a real handicap.

My first attempt at porting was in 1962 with dad's old gigantic electric grinder. What was it called......a Dumore? Oh yeah and no burrs, just old stones that dad had tossed out. Any polishing was done with a 1/4" rod, a slot cut lengthwise in the end and crocus cloth wrapped through the slot. First time you wrap the cloth in the wrong direction ya'll got a shock coming as the crocus cloth splatters in all directions.

 

[PRH]

1962 huh?
You have a pretty big “head” start.
It was about 23-24 years after that for me.
I too started out with stones.
“Polishing” was just running the stones slower.

 

[j par]

He did say it....... and I quoted it..... then just reiterated/expanded on it.

I’m not being critical at all.
I’ve already stated that he’s gotten more out of those style heads than I have.

Making trouble!!??....
You don't have to explain yourself to the internet superhero he'll have another beer and forget about...
So I leave this thread alone and how many times was my name mentioned and referred to?... I feel like Donald Trump nobody likes what I say, but nobody can stop talking about me...
It should be tips and results for the people who already know how to do this stuff... Again more terminology and things need to be explained for the not knowing... it's not like we're all going to run out and buy a flow benches for the one or two sets of heads we have...