Head advice on BBC
#42
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Originally Posted by jeffswav
My wife shot down the new heads. I need to keep my cost down.
Jeff
Jeff
![Drink](/forums/images/smilies/drink.gif)
ITS BETTER TO ASK FOR FORGIVENESS THAN ASKING FOR PERMISSION
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Go for it and let us know the power results
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#43
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Originally Posted by jeffswav
...my machinist has a set of 3993820's and 353049's. Thanks,
Jeff
Jeff
Anyway, you'll be much farther ahead with the larger 049 oval port heads vs the peanut ports. Also, if I remember correctly "JimV' told me that the 049's don't flow much past .550" lift---even after porting so, you obviously don't want to cam it much beyond that.
#44
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Originally Posted by KAAMA
Jeff, I'd snatch up those "049" castings from your machinist!!! I didn't originally see this when you posted it, but the 353049 castings from GM (we call them "049" castings) are an excellent head for your engine.
I do know Gen VI heads work on Gen IV blocks. Gen V blocks have real big core holes at the head surface. I'm thinking that combo will leak...
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Patrick
Patrick
#45
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Originally Posted by Pat McPherson
Will Gen IV head castings work on a Gen V engine block???
I do know Gen VI heads work on Gen IV blocks. Gen V blocks have real big core holes at the head surface. I'm thinking that combo will leak...
I do know Gen VI heads work on Gen IV blocks. Gen V blocks have real big core holes at the head surface. I'm thinking that combo will leak...
#46
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Originally Posted by KAAMA
Pat, I really don't know! I know you brought that up before and I completely forgot---good point!!! My bad. Are you sure there isn't a gasket that will allow them to mate without leaks? I'm going to ask around.
When GM retooled for the Gen VI block and head castings they fixed a lot of the incompatibility issues that exist with the Gen V castings. The after-market companies have designed their heads to work on all generations of blocks.
It sounds like we have a good topic to start another thread...
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Patrick
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#47
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Just wanted to keep you guys updated. My machine shop had a set of 820's from a 71 454. I am having new hardened seats installed on the exhaust, severe duty valves, 2.19 & 1.88 and I am using the guild plates, rockers and studs from my other heads. I am going to do some port & bowl work and I should be ready to go. As far as the Mark IV Gen V compatibility goes, I have been told a Mark IV head will fit a Gen V block with Gen V gaskets. A Gen V head will not fit on a Mark IV. Should have about $850 in the heads with me doing the port work. I will let you guys know how it turns out.
Thanks,
Jeff
Thanks,
Jeff
#48
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Originally Posted by hondatv
amer3 : can I get a copy of the flow chart? I'm thinking about buying a set for my 540.
#49
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Originally Posted by jeffswav
After doing more reserch I am probably going to find a set of L29 vortec castings, I already have rockers, studs, valve guides and springs. All I need are the castings. If anyone has a good deal on a set let me know. I am located in the St Louis MO area.
Thanks,
Jeff
Thanks,
Jeff