P8R b20 head vs VTEC head

[Dark93DX]

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,

 

[Dark93DX]

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.

 

[phunky.buddha]

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.

 

[Dark93DX]

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?

 

[phunky.buddha]

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.

 

[Dark93DX]

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.

 

[erebunicrx]

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.

 

[Dark93DX]

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