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P8R b20 head vs VTEC head

Discussion in 'Engine Building' started by Dark93DX, May 27, 2007.

  1. Dark93DX

    Dark93DX New Member

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    From what I've been able to gather from searching around is that some B20's came with a P8R Non-vtec head that has an 84mm bore, with larger ports and vtec sized 33mm valves.

    Other then the fact that the vtec head comes with more aggressive cams/valve train wouldn't it be pretty close to the P8R head in terms of flow measurements?

    Would a b20 with a P8R head & more aggressive cams be basically the same thing as a b20/vtec? or am I missing something here?


    Cheers,
  2. Dark93DX

    Dark93DX New Member

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    ya sorry, i was refering only to the upper part of the powerband, but you're right with the two cams profiles VTEC's got the best of both worlds, across the power band.

    I was looking into the P8R head's as they had the bigger valves and ports as it would be a much better starting point then a regular ls head and as a cheaper alternative from going b20/vtec.

    I thought I read somewhere that it can flow up to 220cfm/min vs the type r 's 245cfm/min, but don't quote me on that.
  3. phunky.buddha

    phunky.buddha Admin with a big stick Admin

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    The P8R head flows really well. If you can get one and are willing to tune for the bigger cams, go for it. It's a pretty sweet setup.
  4. Dark93DX

    Dark93DX New Member

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    Initally I'll just use an LS ECU, but evenually when i go to bigger cams I was thinking of using a chipped p28.

    Do you know if there are any valve clearence issues on the b20's when using bigger cams like 403's or 404's?
  5. phunky.buddha

    phunky.buddha Admin with a big stick Admin

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    Not sure... the guys on nonvtec.com know the P8R head pretty well though. I don't think you're going to have problems with the 404s.

    With the bigger cams, you don't want to go to a VTEC ECU- just tune the LS ECU.
  6. Dark93DX

    Dark93DX New Member

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    thanks, I'm not even sure what pistons come with a b20 w/ P8R since its compression is listed as 9.2:1. It's supposed to off of some odd ball JDM only Orthia or something like that.
  7. erebunicrx

    erebunicrx my name is Dale

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    i had problem with the springs coilbinding with the 404's and crower retainers for the ls. also comparing the ports to a ls head they were identical. not sure where people come up with they flow better. only differance was that the intake valves were 1mm bigger than the ls valves.
  8. Dark93DX

    Dark93DX New Member

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    I thought the ls head had 31mm vavles and the P8R had 33mm valves.

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