Speedmaster Heads - Valves Any Good?
September 28th, 2021, 02:34 PM
#1
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Speedmaster Heads - Valves Any Good?
On a set of Speedmaster 455 heads. Are the supplied valves any good or are they junk and should be replaced?
The castings are supposedly OK but the springs, valves and other parts included are not the best parts???
Do the Speedmaster heads flow about the same as the last generation Edelbrocks?
The castings are supposedly OK but the springs, valves and other parts included are not the best parts???
Do the Speedmaster heads flow about the same as the last generation Edelbrocks?
September 28th, 2021, 06:32 PM
#2
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Join Date: Nov 2008
Location: Central Fl
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On a set of Speedmaster 455 heads. Are the supplied valves any good or are they junk and should be replaced?
The castings are supposedly OK but the springs, valves and other parts included are not the best parts???
Do the Speedmaster heads flow about the same as the last generation Edelbrocks?
The castings are supposedly OK but the springs, valves and other parts included are not the best parts???
Do the Speedmaster heads flow about the same as the last generation Edelbrocks?
No, the intake side doesn’t flow much better than any big block iron. Out of the box the intake tract needs help, bad casting concentricity vs the CNC’d opening.
I’ll have a full CNC Program available for these very shortly though.
September 29th, 2021, 04:51 AM
#5
I did it with first gen Edelbrock stock hardware. It ate a valve and trashed the engine. I believe it was due to the faster ramps, and the springs couldn't handle it. Cam was puny- 491/510, 236/242.
September 29th, 2021, 05:54 AM
#6
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There's some confusion there, and folks just combining a bunch of stuff into one single statement.
Out of the box, fully assembled, the speedmaster machining isn't the best. The valve guides may be too tight or too loose, the seats may not be cut very well, surfaces may not actually be flat. Note that all of that applies to Edelbrock heads also!
The springs on the speedmaster might be more questionable than most, so they need to be checked for seat and open pressure and it'd be good to make sure they don't weaken quickly.
I don't think the valves are "bad". Heavy, sure, but that's probably not much of an issue for anyone that's looking at one of these assembled heads.
Retainers are, well, retainers. The common quality parts are pretty... common. Same with locks. I will say that I've had experience with cheaper locks being more trouble to work with and more likely to grab and nick the valve when compared to name brand locks.
Make sure the spring installed heights are correct!!
So, with all that in mind, and since bare units are available, shops would prefer to just buy a bare unit and set it up themselves. That then just gets summarized into "out of the box is junk, just buy a shop's package". Many of the parts (valves, springs, locks, seals) have a fairly small price jump to go from "dirt cheap questionable" to "higher quality with a nice feature or two", so shops will emphasize that.
Out of the box *can* be just fine, just has to be thoroughly checked and possibly re-machined. And, well, that goes for Edelbrock castings too. All 6 edelbrock heads I've had my hands on have needed to be resurfaced.
Now, this all still depends on what you're doing with the engine. Stock-ish build, mild flat tappet hydraulic cam, felpro blue head gaskets? Hell, give the heads a good cleaning and throw them on!
Roller cam? Definitely check the springs. I bought the "flat tappet" setup because it was on fire sale with the intention of buying springs. Well, it took 3 sets of springs from Comp to get 16 that had even vaguely similar pressures.
Moral of the story: doesn't matter what it is or who it comes from, parts need to be checked.
Out of the box, fully assembled, the speedmaster machining isn't the best. The valve guides may be too tight or too loose, the seats may not be cut very well, surfaces may not actually be flat. Note that all of that applies to Edelbrock heads also!
The springs on the speedmaster might be more questionable than most, so they need to be checked for seat and open pressure and it'd be good to make sure they don't weaken quickly.
I don't think the valves are "bad". Heavy, sure, but that's probably not much of an issue for anyone that's looking at one of these assembled heads.
Retainers are, well, retainers. The common quality parts are pretty... common. Same with locks. I will say that I've had experience with cheaper locks being more trouble to work with and more likely to grab and nick the valve when compared to name brand locks.
Make sure the spring installed heights are correct!!
So, with all that in mind, and since bare units are available, shops would prefer to just buy a bare unit and set it up themselves. That then just gets summarized into "out of the box is junk, just buy a shop's package". Many of the parts (valves, springs, locks, seals) have a fairly small price jump to go from "dirt cheap questionable" to "higher quality with a nice feature or two", so shops will emphasize that.
Out of the box *can* be just fine, just has to be thoroughly checked and possibly re-machined. And, well, that goes for Edelbrock castings too. All 6 edelbrock heads I've had my hands on have needed to be resurfaced.
Now, this all still depends on what you're doing with the engine. Stock-ish build, mild flat tappet hydraulic cam, felpro blue head gaskets? Hell, give the heads a good cleaning and throw them on!
Roller cam? Definitely check the springs. I bought the "flat tappet" setup because it was on fire sale with the intention of buying springs. Well, it took 3 sets of springs from Comp to get 16 that had even vaguely similar pressures.
Moral of the story: doesn't matter what it is or who it comes from, parts need to be checked.
September 29th, 2021, 06:59 AM
#8
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Join Date: Nov 2008
Location: Central Fl
Posts: 7,863
Actually the valve job on the Speedmasters out of the box is fairly decent, considering.
The only real issue I see is the springs, more specifically the spring rates. They’re not really ideal for a flat tappet or roller.
The only real issue I see is the springs, more specifically the spring rates. They’re not really ideal for a flat tappet or roller.
September 30th, 2021, 03:53 PM
#9
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Join Date: Sep 2013
Posts: 1,945
On set of speedmasters that were run less than a year the guides were shot. that was just one set i got through my shop.
had a few chevy heads withe same problem,,shot within months. google speedmaster valve guide problems. i dont know what kind of material they are but they are more yellow looking than a good bronze guide.
had a few chevy heads withe same problem,,shot within months. google speedmaster valve guide problems. i dont know what kind of material they are but they are more yellow looking than a good bronze guide.
October 18th, 2021, 06:06 AM
#10
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Location: Colorado Springs Colorado/Thousand Oaks Ca
Posts: 1,719
On set of speedmasters that were run less than a year the guides were shot. that was just one set i got through my shop.
had a few chevy heads withe same problem,,shot within months. google speedmaster valve guide problems. i dont know what kind of material they are but they are more yellow looking than a good bronze guide.
had a few chevy heads withe same problem,,shot within months. google speedmaster valve guide problems. i dont know what kind of material they are but they are more yellow looking than a good bronze guide.
October 18th, 2021, 08:00 AM
#11
This guy was asking. Maybe you could help him.
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