LS/vtec ? is it true?? I heard that u wont get enough Valve clearance when u swap a b16 head on a ls block with ls pistons is that true? as well as they said i needed to throw in the B16 pistons in place of my LS pistons

 

"they" always seem to be wrong. According to all my research, the piston-valve clearance will be ample. As far as the pistons go. The ls ones will yield a low 9.6:1 cr and the b16a pistons pop the cr up to 11.5+-. They will both work.

However, i'm a "they" too. Do mucho research and talk to lots O people before commiting to somthing expensive like this contraversial engine build.

d

 

i ran stock ls pistons with a b16 head with itr cams. valve clearance was ok. just dont plan on advancing the intake cam. you can always widen the ls valve reliefs, i have heard of a tool that will shave off hundreths of an inch off of the pistons.

 

which would be better ab route to go with ?
Ls pistons or B16 pistons??

 

vtec pistons always

 

I think they say that a full point cr increase will yield 7% more power (or was that 7hp)? More power with the b16 pistons (with higher octane gas too), but more wear and tear. Whatever you want.

d

 

stock bottom end with b16 head will give 9.53:1 compression
ls bottom with standard bore pr3 pistons will give 11.29:1 compression
ls bottom with standard p30 pistons will give 11.51:1
with usdm itr pistons 10.77:1
with jdm itr pistons 11.28:1
pr3 pistons and jdm itr pistons are pretty close in compression. if you are looking for a cheap piston, then get used b16 pistons. i used usdm itr pistons and they made good power over stock ls pistons. i would suggest itr pistons for your ls/vtec.

 

just a curious question. Do vtec pistons have some strength or weight advantage, or is the recommendation just due to increased power?

d

 

they used to increase compression which gives you more horsepower and the valve reliefs on top of the pistons are wider for the vtec valves. vtec valves are bigger than the non vtec ls valves, so you have a chance of hitting the pistons with the vtec valves.