SPEEDMASTER HEADS

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Amata Bene

Amata Bene

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Let me start by stating I have read A LOT of the "Speed Master Heads" sticky and am looking for some time and miles update. I ask because after about 30hrs of hand porting work on a set of J-heads (PSA - Don't just be cautious of the water areas, also be mindful of the valve cover bolt bosses.) and making arrangements to drop off at the machine shop for a Hughes hardware upgrade. I happened across a set of "in the box" bare Speed Master heads. My Hughes upgrades consist of rocker set 15063, springs 1129 installed press: 145# 425# @ .700, Int. 1006 11/32 stem 2.02 , Ex. 1013 11/32 stem 1.6, with retaining hardware. Not to mention cam, lifters, and push rods. Will these heads respond well and last with the upgrades? The advantages of the head are obvious lighter weight, tighter comb. chamber, and most importantly PRETTY, lol, paints pretty too. I, like the rest of you would like to only build this once by choice. Some feedback on similar set ups would be nice. The vehicle will spend the majority of it's life on the streets getting tickets, lol. My guess is roughly 75/25 street/strip. It will see some hard hits. It will let the smoke out. It will show off. Or, rather, I'll be doing all that and paying fines :).
 
A member that passed away (Pittsburgh Racer) made several posts on many different small block heads.
Speedmaster was one that he thought was not that bad for the money.
Maybe find some of his old posts here.
 
@Earlie A has sort of taken up the mantel and done a lot of work with the SM heads. Lots of great info from both @pittsburghracer and him on these heads. If I recall they would flow around 250 or just shy out of the box and peak around .500 lift? Someone is sure to correct me if I'm wrong. Springs etc really depend on the cam so I can't speak to that but the heads are a solid choice and I'm sure you'll be happy with them.
 
Still reading through all the post in the SPEEDMASTER index thread. Seems to be more approval of the heads than disappointment. A lot of people beating on them at the track also. I think for the money it will be a good option. Cost wise it will be a wash by the time all the work is done to the what were stock J-heads. Check & cut spring lands for level, cut new seat in the ex. and increase the In. to 2.02 and and cut seats, bowl cuts on both, check and mill for flatness, replace guides and drill.... Yeah, probably a wash. They will inspect these heads (fingers crossed) make all necessary corrections and load them up for me. All the fine adjustments will be left to me when I put the engine together. If anything gets screwed up that's probably where it will happen. And then I still have a set of completely ported J-heads waiting to be finished and put on something in the future. Can never have to many old MOPAR engine parts in storage. Their just like Harley parts. Lord knows I got a butt-load of those. Just ask my wife.
 
Off topic but... COULD SOMEBODY PLEASE STOP THE F__ING RAINING !!! It's been raining since Sunday :mad:
 
@Cuda416 is right on with the flow specs. My testing has a stock Speedmaster at high 240s/low 250s at 0.500 on the flow bench. Should be pretty good for a 340/360 on the street. Head would be a little small for a 400 ci+ motor.

At a minimum I would clean/wash the heads good, check valve to guide clearance and make sure the valves seal well on the seats either by vacuum (preferred) or by lapping. If you have a good straight edge check the deck diagonally for flatness. It is a Chinese head after all. My preference on aftermarket SBM heads is Trick Flow then ProMaxx then Speedmaster. Of those the SM is the least expensive and is probably a good value.

I've done a good bit of testing, but assembled only a few engines and I've done no racing. There's lots of guys here with more valuable info the me, so take my advice for what it's worth, lol.
 
Earlie A said:
@Cuda416 is right on with the flow specs. My testing has a stock Speedmaster at high 240s/low 250s at 0.500 on the flow bench. Should be pretty good for a 340/360 on the street. Head would be a little small for a 400 ci+ motor.

At a minimum I would clean/wash the heads good, check valve to guide clearance and make sure the valves seal well on the seats either by vacuum (preferred) or by lapping. If you have a good straight edge check the deck diagonally for flatness. It is a Chinese head after all. My preference on aftermarket SBM heads is Trick Flow then ProMaxx then Speedmaster. Of those the SM is the least expensive and is probably a good value.

I've done a good bit of testing, but assembled only a few engines and I've done no racing. There's lots of guys here with more valuable info the me, so take my advice for what it's worth, lol.
Click to expand...
Reading through the Dyno Head Shootout thread right now. You know...Cuz it's still flipping raining. I should mention this is a 340 build with 1.6 rockers and more than likely the 232/236 @ .050 Hughes cam. Haven't pulled the trigger yet on the cam. Freshly machined block @.040, KB slugs, full float rods and all balance on a steel forged crank.
 
Amata Bene said:
Off topic but... COULD SOMEBODY PLEASE STOP THE F__ING RAINING !!! It's been raining since Sunday :mad:
Click to expand...
We wish for rain. Last year Southern Nevada went 214 days without any measurable rain.
HOT HOT ! here now...
 
Let's swap for a year. I'll need a car hauler to come home though. Y'all ain't got no rust problems in the desert.

:lol:

On second thought... I'm good. I love the ocean and some great fishing.
 
What's the rest of your build? Like intakes, aftermarket heads have their place where they work well and not so well, but its all in the intent use.

I have a hand ported set with 2.05/1.60 valves, all aftermarket hardware installed. They seem to drive well on the street.
 
Amata Bene said:
Off topic but... COULD SOMEBODY PLEASE STOP THE F__ING RAINING !!! It's been raining since Sunday :mad:
Click to expand...
CCR asked the same, who'll stop the rain. I wish we had some instead of our weekly dose of ten drop mud rain. It's hard to keep the vehicles clean
 
dano said:
What's the rest of your build? Like intakes, aftermarket heads have their place where they work well and not so well, but its all in the intent use.

I have a hand ported set with 2.05/1.60 valves, all aftermarket hardware installed. They seem to drive well on the street.
Click to expand...
On top will be an Eddy RPM AG with a 750 air sucker. My short coming is in the exhaust. Right now all I have is 1 5/8 NOS Doug Thorley SS headers. I'm doing my best to keep this on the cheap. Engine internals and what not are new but externally trying to get from swap meet and deals on the web and sort. This is not the engine I was planning on building for this car. I have a 400/727 that all this money was suppose go into. It all started with "it just isn't running right". Broken valve spring is how the snowball got formed. Been rolling down hill since. I can see the bottom of the hill now, so that's good.
 
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I was working under my car in the outdoors and we had rain for a week. Some dems are blaming the ICE guys for all the water.
 
Amata Bene said:
Let me start by stating I have read A LOT of the "Speed Master Heads" sticky and am looking for some time and miles update. I ask because after about 30hrs of hand porting work on a set of J-heads (PSA - Don't just be cautious of the water areas, also be mindful of the valve cover bolt bosses.) and making arrangements to drop off at the machine shop for a Hughes hardware upgrade. I happened across a set of "in the box" bare Speed Master heads. My Hughes upgrades consist of rocker set 15063, springs 1129 installed press: 145# 425# @ .700, Int. 1006 11/32 stem 2.02 , Ex. 1013 11/32 stem 1.6, with retaining hardware. Not to mention cam, lifters, and push rods. Will these heads respond well and last with the upgrades? The advantages of the head are obvious lighter weight, tighter comb. chamber, and most importantly PRETTY, lol, paints pretty too. I, like the rest of you would like to only build this once by choice. Some feedback on similar set ups would be nice. The vehicle will spend the majority of it's life on the streets getting tickets, lol. My guess is roughly 75/25 street/strip. It will see some hard hits. It will let the smoke out. It will show off. Or, rather, I'll be doing all that and paying fines :).
Click to expand...
On your J-heads, did you only get into the valve cover rail bolt holes or also into water? The valve cover bolts can get a little sealer applied and that will seal up perfectly good. Breaking into those is not really a problem, so your old heads may still be good and that will save a bunch of money if you already have the parts for them.
 
@Bobzilla the heads are fine. Just the valve bolt boss in one port. Cleaned it up, ran a bolt in the hole, filled in with JB weld. After it set up for a while I gently removed the bolt, let it finish curing and carried on. Couple days later I ran a tap in it, all good. So one pair of fully diy ported J-heads and another set all freshened up collecting dust. Swap meet deal at a great price. Couldn't pass them up. That's also where I picked up the RPM AG dirt cheap. Gotta love a blast cabinet.
 
I built a race only motor for a buddy of mine about 4 years ago that I put SM unported heads on. I did clean up some the flashing in the port, it wasn't much at all. 360 flat top pistons .508 292 comp hydraulic on a 108 LSA installed straight up. Air gap intake and 1 3/4 hooker super comps headers. Has went 11.80s at 112 in a 70 Duster with 140lbs in the trunk. I bet that thing has 1000 runs on it.
 
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Amata Bene said:
Reading through the Dyno Head Shootout thread right now. You know...Cuz it's still flipping raining. I should mention this is a 340 build with 1.6 rockers and more than likely the 232/236 @ .050 Hughes cam. Haven't pulled the trigger yet on the cam. Freshly machined block @.040, KB slugs, full float rods and all balance on a steel forged crank.
Click to expand...
Good thing it's raining,. It is giving you time to get some studying done. :poke: :lol:
 
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