ProComp/Speedmaster aluminum heads

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Sometimes all they’re here for is to make sure there won’t be any “problems” that could have been easily corrected before they were installed.
And the one set of SM SBM heads I had here fell into that category.
That set got nothing but new valve seals and a couple of springs shimmed up.
The big wide seats aren’t the best for performance, but as long the the runout is decent, it’s not going to cause any problems.
Guide clearance was a tick over .002”.
Again, not fantastic for new aluminum heads with bronze guides, but it won’t cause problems.

Sometimes they're here for a check over as well as some minor(or not so minor) enhancements........ sometimes not.

Ootb assembled head:
Lift———in/ex
.100—- 61/49
.200—-120/97
.300—-176/134
.400—-221/153
.500—-240/164
.600—-250/168
.700—-253/168

With a proper valve job and a basic bowl blend I’d expect to see a gain of somewhere in the 10-15cfm range from about .400 lift on up.
 
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pittsburghracer said:
When I see those numbers I just shake my head. If it can’t flow 200 cfm by .300 it’s junk.
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This is where I keep leading back to these heads as a possibility for someone with reasonable expectations from a cheap aftermarket head. Not trying to set the world on fire at the dragstrip, but yet getting some of the benefits of an aluminum head and here's the big one doing it while not falling apart and ruining the motor!..
 
I don’t know if it can or “can’t”.....but in ootb unported form, it doesn’t.

200cfm by .300 lift with any unported SB head with a 2.02 valve isn’t going to be very common...... for any brand of motor.
 
My mistake. I kinda read this on the run packing to go racing. I thought this was the cnc’d heads numbers. Sorry.
 
j par said:
This is where I keep leading back to these heads as a possibility for someone with reasonable expectations from a cheap aftermarket head. Not trying to set the world on fire at the dragstrip, but yet getting some of the benefits of an aluminum head and here's the big one doing it while not falling apart and ruining the motor!..
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Other than weight and relative ease to repair, what are the other benefits to aluminum?
 
I put myself out there as an example of a reasonable expectation...
"IF" I can run pretty much out of the box I would expect to lose around 50 lb of weight off the front of the car? I think a reasonable expectation LOL
I would expect better heat dissipation and distribution and with a tall enough gasket be able to possibly use a little less octane in my fuel?
And the performance enhancement I would hope for but not completely expect this to gain a couple two 3 miles an hour in the quarter mile over the stock iron heads?
 
pittsburghracer said:
My mistake. I kinda read this on the run packing to go racing. I thought this was the cnc’d heads numbers. Sorry.
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It's more of a what can we expect reasonably out of a pair of these heads thread? Are they going to destroy a motor because one didn't spend a little extra money?
 
My budget now zero! LOL this is where you do a lot of research cross your fingers and save your money all the way up till Black Friday to get 35% off the cheapest heads made! And keep your fingers crossed! LOL....












Backup Plan B have the credit card paid down Enough by then.....
 
j par said:
It's more of a what can we expect reasonably out of a pair of these heads thread? Are they going to destroy a motor because one didn't spend a little extra money?
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Only if one of the cheap parts that go into making cheap heads fails. Do ya feel lucky. Lol. I am a budget racer but even on a budget I shy away from bottom shelf items. At 1000.00 to machine a block and balance an assembly, damaged parts, lost races, I just can’t afford it.
 
pittsburghracer said:
Only if one of the cheap parts that go into making cheap heads fails. Do ya feel lucky. Lol. I am a budget racer but even on a budget I shy away from bottom shelf items. At 1000.00 to machine a block and balance an assembly, damaged parts, lost races, I just can’t afford it.
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100% agree in your case this would be a terrible mistake. You're a dedicated racer racing many times a year likely.
I've went twice and have 10 passes this year so far. I would like to get 30 more passes in by the end of the year and I'll be glad to get 10 more passes. I went for one small trip an hour away and quite a few other drives as well. 500 miles? I'd like to easily double all that by the end of the summer but probably won't...
With all that said at the other end of the spectrum with that amount of driving and with my want for just the slightest more performance it really becomes a battle if one should step up to the Edelbrocks? Certainly for my intentions and definitely my budget but even given that my intentions I don't think trickflow is necessary?
 
j par said:
I put myself out there as an example of a reasonable expectation...
"IF" I can run pretty much out of the box I would expect to lose around 50 lb of weight off the front of the car? I think a reasonable expectation LOL

50 pounds is not unreasonable.






I would expect better heat dissipation and distribution and with a tall enough gasket be able to possibly use a little less octane in my fuel?


Aluminum won't do a thing for knock resistance. If you plan on lowering the compression with a thicker gasket, you can do that with your heads. The case can be made that aluminum will lose some power to cast iron.




And the performance enhancement I would hope for but not completely expect this to gain a couple two 3 miles an hour in the quarter mile over the stock iron heads?
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I doubt you will find 2-3 MPH from that head change.
 
PRH said:

Only one way to know for sure.
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Somehow I would think that the unported Speedmaster would be equal or a little better flow over very lightly home ported 596 heads?
Also when I was referring to this mile per hour gain I was really referring to the CNC heads.
 
Also when I was referring to this mile per hour gain I was really referring to the CNC heads.
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Still only one way to know for sure.

Bolt ‘em on and see what happens.

Anything else is just “woulda, coulda, shoulda”.
 
j par said:
Somehow I would think that the unported Speedmaster would be equal or a little better flow over very lightly home ported 596 heads?
Also when I was referring to this mile per hour gain I was really referring to the CNC heads.
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Spend 60 bucks and have 'in your opinion' the best port of your 596 flow tested.
That's how you make your decision.
Any other way is like doing it blind folded..
of which many big name builders love selling **** to guys like you.
 
I think an interesting test would be a set of cnc ported SM heads vs a set of the TF heads...... both run literally right ootb, on some stroker short block that should make solidly over 500hp....... and something closer to 550hp would be better.

I doubt it’ll happen....... but I’d still like to see it.
 
MOPAROFFICIAL said:
Spend 60 bucks and have 'in your opinion' the best port of your 596 flow tested.
That's how you make your decision.
Any other way is like doing it blind folded..
of which many big name builders love selling **** to guys like you.
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LOL...
 
Just buy ProMaxx..... fully assembled..... That will net ya some power
 
318willrun said:
Just buy ProMaxx..... fully assembled..... That will net ya some power
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And probably check them too. lol
More times than not, the heads reveal their hindermant to the combo. How about one port 242cfm @.450 and the rest 218 cfm or so..
All the time.
 
MOPAROFFICIAL said:
And probably check them too. lol
More times than not, the heads reveal their hindermant to the combo. How about one port 242cfm @.450 and the rest 218 cfm or so..
All the time.
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That's probably about one of my home port jobs... LOL
:rofl:
 
j par said:
LOL...
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That's IF you fit that bill.
Anyone can hand you a set of AM heads to toss on and 'better chance than not' you'll go faster... but whats the difference between the heads, beats the **** outta you, right? Not just formulas ...I'd rather learn 'with my combo' what amount 'more' airflow did i need to raise the mph to.. ? and lower et to..? etc and did i just waste a set of heads and hurt myself or did do decent and can build upon that knowledge.
 
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