P8R head on LS block

[LoweredDC4]

I was wondering if this is a legit setup. i know that the p8r head is 84mm and the ls block is 81mm but i have read that some people have this setup and ive read that it will not work because of the different sizes. Does anybody have any first hand experience with this? I have my head off my ls because im replacing the headgasket and while its off i wanna upgrade to get a little more horse power. im too broke to go lsvtec.

 

[klutchDb7]

A b20 head will not up power

 

[TheCrimsonStar]

A b20 head will not up power

Right, it'll give a little more low end torque for takeoff but that's about it.

Sent from my GameBoy Color using Tapatalk.

 

[LoweredDC4]

oh :/ well does anybody know if it will work anyways? i hear its a better flowing head than a LS. it might not increase power but i want a little better flow. Has anybody done this?

 

[klutchDb7]

There is next to no difference stock from my understanding, just give your current head a port and polish and call it good in my opinion

 

[LoweredDC4]

but i hear that the p8r head flows better than a port and polished ls head, there has to be some kind of increase. there might be drop in compression though..

 

[klutchDb7]

Uh, who said that? I feel that's a load of crap

 

[LoweredDC4]

well p8r heads do have better flow, comparable to vtec heads

 

[klutchDb7]

Source? I highly doubt that, otherwise everyone would do a p8r head swap

 

[LoweredDC4]

well thats what i thought too, but p8r heads are rare and hard to come by. i cant find an intial source but on my readings i keep coming across that the head flows really well.

 

[ramatan]

i know that they work on b20 but not sure about b18b or a and the reason why p8r head makes more power is because it has bigger size valve the same size has a vtec engine but i don't think the grains or great enough personally

 

[LoweredDC4]

yeah i hear the intake valves are biggers. this probably would be an awesome build for someone who dont/cant go lsvtec. but i cant find a definite answer if there would be a problem installing the head on teh ls block. i know there will be overlap. so im asking if anybody has had any first hand experience with this?

 

[72Spitfire]

Both the B20 and B18B came with the P-75 head. Some B20's came with the more rare P8R head. You can bolt a P8R to a B18 with no issues except a drop in compression as the B20 had higher compression pistons. The P8R has bigger exhaust valves than the P75, it does flow slightly better also. There are charts floating around the internets if you do some digging. I would for you, but I must leave for work in a few minutes.

 

[LoweredDC4]

so i can put a p8r head on a ls block. i might consider doing this sometime. higher compression pistons with the p8r head.