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steelcomp was here
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Discussion Starter #1 (Edited)
I'm just about ready to start building up a few sets of large oval port, open chamber BB Chev heads. I have four sets to start, and they'll be set up as the following:

*Castings cleaned, mag'd and inspected. Completely deburred, sharp edges broken, water passages cleared of casting flash, etc.
*All new bronze liners honed w/ correct stem clearances
*NEW 11/32 stem severe duty stainless valves 2.19 or 2.25 intake/ 1.88 ex
*NEW 1.55" hyd roller or flat tappet, super clean silicone steel "PacAlloy"type valve springs
*NEW Chromoly 10* steel retainers and locks
*NEW 4140 studs and guide plates
*VTO seals
*Custom 5 angle intake valve job, radiused ex (45* or 50*)
*Valve heights equalized
*Bowls blended
Fully assembled w/ proper installed height, chambers cc'd (not matched, checked for volume for compression calculation) and fresh surface on decks.

If anyone might be interested in a set of these, PM me.
I'll have flow numbers available on the first set I do, so we can put to rest any misconceptions on how well these heads will work on engines below 500ci and operating at or below 6000 rpm. These will be quality assemblies mostly with American parts, not cheap Chinese crap.
Stay tuned.
 

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I'm just about ready to start building up a few sets of large oval port, open chamber BB Chev heads. I have four sets to start, and they'll be set up as the following:

*Castings cleaned, mag'd and inspected. Completely deburred, sharp edges broken, water passages cleared of casting flash, etc.
*All new bronze liners honed w/ correct stem clearances
*NEW 11/32 stem severe duty stainless valves
*NEW 2.19 or 2.25 intake/ 1.88 ex
*NEW 1.55" hyd roller or flat tappet, super clean silicone steel "PacAlloy"type valve springs
*NEW Chromoly 10* steel retainers and locks
*NEW 4140 studs and guide plates
*VTO seals
*Custom 5 angle intake valve job, radiused ex (45* or 50*)
*Valve heights equalized
*Bowls blended
Fully assembled w/ proper installed height, chambers cc'd (not matched, checked for volume for compression calculation) and fresh surface on decks.

If anyone might be interested in a set of these, PM me.
I'll have flow numbers available on the first set I do, so we can put to rest any misconceptions on how well these heads will work on engines below 500ci and operating at or below 6000 rpm. These will be quality assemblies mostly with American parts, not cheap Chinese crap.
Stay tuned.
Okay lets see if we can play nice. I, in the past have taken 049 heads and opened the intake to a 291 rectagular intake port, opening in about 1 inch into the port before it gets to thin on the top side to match a large port manifold and have had reasonable gains on smaller motors. Say 440 to 468. Have you done this and done any flow testing. I will add that bowl blending,valve relief,combustion chamber work and porting is involved. Serious question here. Mark
 

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steelcomp was here
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Discussion Starter #4
Okay lets see if we can play nice. I, in the past have taken 049 heads and opened the intake to a 291 rectagular intake port, opening in about 1 inch into the port before it gets to thin on the top side to match a large port manifold and have had reasonable gains on smaller motors. Say 440 to 468. Have you done this and done any flow testing. I will add that bowl blending,valve relief,combustion chamber work and porting is involved. Serious question here. Mark
OK...playing nice...if I disagree with you, don't take it personal.
I don't know of any benefit to opening oval ports to a rectangular shape. The idea behind what I want to accomplish is to take advantage of the oval port size, optomize the head as is by increasing valve size and the quality of the valve job, and keep costs as low as possible in order to pass on a solid performing, professionally assembled, reliable, quality head at a very reasonable price. The oval ports have plenty of potential just the way they are. A rect port intake on these heads without a full port job, and I mean FULL port job would kill runner velocity and carb signal. I would strongly recommend any of the good oval port intakes with these heads. My target use for these heads is engines below 500ci, and up to 6000 rpm. On smaller displacements 6500+rpm, maybe more depending on the rest of the combination. On a 496 spinning 6000rpm, these heads should perform very well. Of course an oval port intake would be the best choice, but if someone was to bolt on a rect port intake, so be it. The performance would still be there. I'll look into the chambers when I get the first flow bench results. If the returns justify the time I may do some work there. There is a ton of room for improvement with the existing port shape and corresponding intake manifold work, keeping the CSA's as small as possible for max velocity and still gaining good flow improvements. There are plenty of options available from the base head package.
 

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OK...playing nice...if I disagree with you, don't take it personal.
I don't know of any benefit to opening oval ports to a rectangular shape. The idea behind what I want to accomplish is to take advantage of the oval port size, optomize the head as is by increasing valve size and the quality of the valve job, and keep costs as low as possible in order to pass on a solid performing, professionally assembled, reliable, quality head at a very reasonable price. The oval ports have plenty of potential just the way they are. A rect port intake on these heads without a full port job, and I mean FULL port job would kill runner velocity and carb signal. I would strongly recommend any of the good oval port intakes with these heads. My target use for these heads is engines below 500ci, and up to 6000 rpm. On smaller displacements 6500+rpm, maybe more depending on the rest of the combination. On a 496 spinning 6000rpm, these heads should perform very well. Of course an oval port intake would be the best choice, but if someone was to bolt on a rect port intake, so be it. The performance would still be there. I'll look into the chambers when I get the first flow bench results. If the returns justify the time I may do some work there. There is a ton of room for improvement with the existing port shape and corresponding intake manifold work, keeping the CSA's as small as possible for max velocity and still gaining good flow improvements. There are plenty of options available from the base head package.
Thank you for your'e response. I fully agree to the potential of the large oval in proper application. The only reason this was brought up was I have done it for budget guys that would stumble onto rec manifolds and want to run them on an existing long block, Me for one. The best case would be, your'e pulling the heads anyway why not shop around. Then the small motor syndrome steps in. Mark
 

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steelcomp was here
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Discussion Starter #6
Thank you for your'e response. I fully agree to the potential of the large oval in proper application. The only reason this was brought up was I have done it for budget guys that would stumble onto rec manifolds and want to run them on an existing long block, Me for one. The best case would be, your'e pulling the heads anyway why not shop around. Then the small motor syndrome steps in. Mark
There are several thoughts on the big intake/oval port deal. The consensus among those way more experienced than myself is that opening up the ports to match the intake has no benefits, where in some cases, the mismatch does. Some will intentionally mismatch the floor (intake larger) thinking the step will allow some turbulence to keep heavier fuel in suspension and help prevent puddling/streaming in the intake. Others will say the air will pack against the head intake flange surface and create a boundary layer of it's own providing a smooth transition. Some will go the other way o a set of rect port heads and use an oval port intake in an attempt to increase port velocity, and it works pretty well. Also when an intake is smaller than the port, the edges of the port on the intake flange can act as a shear against reversion.
 

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"The" masheenist
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Will these fit on a 440 Dodge?

If so, I would take a set.

Brian
 

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"The" masheenist
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There are several thoughts on the big intake/oval port deal. The consensus among those way more experienced than myself is that opening up the ports to match the intake has no benefits, where in some cases, the mismatch does. Some will intentionally mismatch the floor (intake larger) thinking the step will allow some turbulence to keep heavier fuel in suspension and help prevent puddling/streaming in the intake. Others will say the air will pack against the head intake flange surface and create a boundary layer of it's own providing a smooth transition. Some will go the other way o a set of rect port heads and use an oval port intake in an attempt to increase port velocity, and it works pretty well. Also when an intake is smaller than the port, the edges of the port on the intake flange can act as a shear against reversion.
Agreed, turbulence and atomizing of the feul is a way to look at port diameters on the head vs the manifold. Personally I thought that to go from a rec manifold to an oval large port head would create a problem with feul puddling and create a idle tune nightmare and on the other hand a smoother transition to a smaller runner would help atomizing without to much reversion but I geuss that would depend on the cam and the amount of low RPM vacuum being developed. I geuss it's all test and try to see what works for the combo. I am in the starting stages of doing a small motor 781 head 9.5 motor with a rec t/r and a pair of baby carbs and small cam for feul economy and alittle rompability. We shall see. Mark
 

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steelcomp was here
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Discussion Starter #11
Agreed, turbulence and atomizing of the feul is a way to look at port diameters on the head vs the manifold. Personally I thought that to go from a rec manifold to an oval large port head would create a problem with feul puddling and create a idle tune nightmare and on the other hand a smoother transition to a smaller runner would help atomizing without to much reversion but I geuss that would depend on the cam and the amount of low RPM vacuum being developed. I geuss it's all test and try to see what works for the combo. I am in the starting stages of doing a small motor 781 head 9.5 motor with a rec t/r and a pair of baby carbs and small cam for feul economy and alittle rompability. We shall see. Mark
Bottom line with all that is now days there's no reason to put a rect port intake on oval ports unless it's all you have.
 

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Bottom line with all that is now days there's no reason to put a rect port intake on oval ports unless it's all you have.
Steel comp, That was the point I was trying to make!! At times it comes down to what you have to get where you can go. Just wanted your'e input on combos for the not so rich and homeless. At times you take what you have and make it better rather than spend a b-load of money and watch your'e toy ferment in the garage cause now you can't afford to see the water. M
 

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Hey now, I know you wouldn't say that to my face! :|err

I know you were writing about your POS and not my POS.

Just kidding with ya'.
Rod, Your'e boat is DEFFINETLY no P.O.S. I see a 100 mph boat that will get there with time in the seat and tune. Sorry if you got that idea. Mark
 

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I'm just about ready to start building up a few sets of large oval port, open chamber BB Chev heads. I have four sets to start, and they'll be set up as the following:

*Castings cleaned, mag'd and inspected. Completely deburred, sharp edges broken, water passages cleared of casting flash, etc.
*All new bronze liners honed w/ correct stem clearances
*NEW 11/32 stem severe duty stainless valves 2.19 or 2.25 intake/ 1.88 ex
*NEW 1.55" hyd roller or flat tappet, super clean silicone steel "PacAlloy"type valve springs
*NEW Chromoly 10* steel retainers and locks
*NEW 4140 studs and guide plates
*VTO seals
*Custom 5 angle intake valve job, radiused ex (45* or 50*)
*Valve heights equalized
*Bowls blended
Fully assembled w/ proper installed height, chambers cc'd (not matched, checked for volume for compression calculation) and fresh surface on decks.

If anyone might be interested in a set of these, PM me.
I'll have flow numbers available on the first set I do, so we can put to rest any misconceptions on how well these heads will work on engines below 500ci and operating at or below 6000 rpm. These will be quality assemblies mostly with American parts, not cheap Chinese crap.
Stay tuned.
There is a machine shop here in colorado springs that does a 505 ci bbc build; that is also the only engine he builds. He only uses fully ported 049 heads. He wont sell just ported heads. He easily gets 650 hp with a .600 lift roller. It is amazing what can be done with an 049. I have seen his dyno and shop. I wish I could post a pic of the ports;especially the exhaust ports!
 
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