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One being 2v and the other 4v doesn't relate to valves per cylinder does it? What do they actually refer to?????
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4v have large ports
351 ZH |
351 ZH |
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so if you were to port a 2v head to the same ports it should be the same?
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4 valves per cylinder and 2 valves per cylinder
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unless you are goin to build a engine of 500 horsepower or more 4v heads are the go, thats why they are putting stainless tongues into 4v intake ports to improve the flow because they are to big for a street engine to perform properly I am told. 4v intake |
351 ZH |
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must have been tired when I posted the last one, check out: http://www.performancefo...ndex.php/t-67134999.html
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Yea mate , my 351 was a 4v on vehicle id but that only meant it was a 4 venturi carb.
351 ZH |
351 ZH |
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thanks guys I've got at 2v heads now not sure whether i just work them or go 4v I'm just going to have a mild streeter.
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2V is the best way to go unless you are pulling very high consistent revs on a track. If you want to change heads these days, Ali is the only way to go. 4V heads are really out dated in design, and if your car is just a streeter, 2V or alloy heads will gi
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2v reco heads to suit unleaded, port n polish, good set valve springs. Get a quote on price and compare with set alloy heads, take it from there
351 ZH |
351 ZH |
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Cool thats a great idea I think the heads were done for unleaded cause the guy that I bought the motor off said that it was done for LPG and the valves might of been done. Now I just have to find out do the valves look different if I pull the heads off.
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The heads should be alright if they are to suit LPG, should have hardened seats, inserts for the valve guides and possibly something like stellite valves from memory. I do not think you would be able to identify these items, would probably be a machine sh
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I think I'll just drive it for now and until I'm ready to work the heads or until something happens to the valves. then I have to look at everything all you guys have said tlike pricing alloy heads or just working these or getting 4v heads I dont know. I
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My understanding: 2V heads means its fitted with a 2 Venturi manifold - head, and same with 4V heads. In early models, the intake manifold was casted part of the head, so could only be fitted with the orig venturi carb. to upgrade to a 2V head means u
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anyway so far I've got the 2v heads and an edelbrock performer manifold and 650 holley to go on. well see how they go
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4v heads have bigger inlet & exhaust ports, also have bigger valves(exhaust ports are too big). I have ported 302 2V heads on mine & that's the way to go as they have the closed chamber design which raises the compression ratio. A stock 2v head won't flow
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One thing that confuses a lot of people in regards to 2V and 4V with the clevo engines that on the XCs with the clevos they have 4V on the compliance plate. In this case it means 4 venturis, or to put it in simpler terms, a 4 barrel thermoquad carby. Th
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Guys thanks so much for that I think that now i will price up porting the 2v heads and new alloy heads and go that route just have to work out a good street cam to go with my edelbrock performer and 650 holly. thanks again this really helped
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I found crane F238 cam shaft to be very good that's what i'm running in mine, makes good power & torque from about 2800rpm to 6000rpm, not overly lumpy, very good street cam but it is a solid cam so you would need screw in studs, guide plates, solid lifte
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does that mean with solid cam it becomes something you have to maintain. if you leave it hydraulic is that ok?
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