ok heres my problem, im building a ls-T and have the chance to get a jdm b20 head, i dont know if its the rare p8r but it is for sure jdm. now my question is, what would be the advantages/disadvatanges or can i even use it at all? thanks in advance..

 

if it's not a p8r, it's the same thing as a regular ls head

 

but if its a p8r head.. can i use it?

 

yes you can. but the cr will be lower due to the p8r's bigger combustion chamber.

 

so i can in turn run more boost then?????

 

Yeah, except you'll still have the same power limit as before. In other words, lower CR on a built engine just gives you a bit more tuning leeway and slightly longer spoolup due to the engine not being as effecient.

I hope you're doing it because you either don't have an LS head, or you're getting the b20 head for free. The difference honestly is like the diff between choosing a z6 or y8 head for a mini-me. Use whats cheapest to save up for cams or vtec.

 

ok so i uderstand this 100%
with a lower comp ratio it will take longer to spool
im running i t3 t4 .63 ar
stock ls motor rebuilt with new honda parts oem bearing etc.
i have no head for it but i can get a jdm b20 head intake manifold and throttle body for 120.00.
so my next ques is if i get that head i want to get it hot tanked and shaved to help spool time?? opinons please

 

?

 

get an aftermarket intake manifold while you have things apart and are piecing it together. your torque above 5000 rpms will thank you

 

k so i can use a jdm b20 head and it will seal ok on the ls block???
should i shave it to make up for the diff in comp??????
help

 

bump

 

it will bolt to the ls block. if it's a regular p75 casting you should have to mill it or anything unless it's warped.

 

what about if its a p8r head?

 

?

 

no help?

 

the p8r will not work unless ur bottom end is a 2.0 or 84mm bottom end. The p8r head has bigger valves like vtec and chambers open to 84mm. So no it wont work unless u have a 2.0 LS bottom end

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AMLS4dr200whp &raquo;</TD></TR><TR><TD CLASS="quote">the p8r will not work unless ur bottom end is a 2.0 or 84mm bottom end. The p8r head has bigger valves like vtec and chambers open to 84mm. So no it wont work unless u have a 2.0 LS bottom end </TD></TR></TABLE>

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