i have a ls vtec, possibly around 12.1 compression

itr pistons gs-r head ls block obviously...


was wondering wat would be better power for me spec III or spec iv


lemme kno im trin to search for info not much i can find i dunno

 

i would say the bc4 with that compression, but you may want someone that actually has the cams to answer this.

 

yea bump i dunno wat to get lol

 

are you sure your compression is that high.

just wondering because just ITR pistons in an ls block with gsr head and nothing else wont yield 12:1

 

if ur atleast 11.1 or higher i would go with bc4s.

 

i dunno kus i work at stage2 and the owner built the block and they say its around 11.8-12.1 sum where around there... my head is milled like .10 its like a resurface but makes a lil difference i guess

 

https://honda-tech.com/zerothread?id=1078612

Here you go man they basiclly look the sam down low but the BC4 dominates high end horspower. I was trying to decide between these two cams but i ended up buying the skunk pro1+

 

your no where near 12.1 compression

the resurface head wont really do anything

usdm itr pistons =10.6 cr gsr head =+.2cr ls crank=+.2cr = 11.1

jdm itr pistons =11.1 cr +gsr head +.2cr=11.2 + ls crank +.2cr = 11.4

 

aight i got 11.5 cr

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by riceball777 &raquo;</TD></TR><TR><TD CLASS="quote">your no where near 12.1 compression

the resurface head wont really do anything

usdm itr pistons =10.6 cr gsr head =+.2cr ls crank=+.2cr = 11.1

jdm itr pistons =11.1 cr +gsr head +.2cr=11.2 + ls crank +.2cr = 11.4 </TD></TR></TABLE>

man, dont say that because you really have no idea what he is running.

first off, milling the head will do something, in fact it can make as big a difference as ~0.3 of compression even when you only mill it 0.01...

and second there are many other factors that will keep bumping up the compression. ie valves, thickness of headgasket(can make a huge diff), etc...

but back to the original question, it would be helpful to know your entire setup. but what it is looking like to me is that 3+ will suite you just fine

 

gsr block here, with ls crank and rods, with jdm type r pistions and gsr head comp is like 11.6

 

Well the cams make the same power to 7500 rpm, at that point the 3's start to fall off and the 4's keep climbing.. Na200whp here piced up killer top end on the 4's compared to the 3+

 

Here's na200whp's dyno plot.. Thanks to him for the use of his plot

 

aight my set up is


97 gsr head milled .10
stock cams stock valve train
LS block jdm itr pistons, ls shot peened rods, blueprinted and balanced crank
b16 tranny

oem head gasket
aebs head studs (and rod bolts)
skunk 2manifold
skunk2 t/b not on yet tho
p28 chipped ecu skunk2
dc 4-1 header which im sellin
2/5 inch str8 pipe to apexi n1
str fuel rail

thats about it unless im forgetin sumthin

 

if you have stock valvetrain i dont think you should use the bc spec 4s then

 

i would do BC 3s, but i have to say that your killing your setup with that Skunk2 throttle body----a straight-through 68mm....which is too big. I bet you can find more power with a stock ITR TB with your setup.

 

well if i go bc4s imma get valve train then lol

bc4s are beastly

and i think the 68mm tb should be aight i dunno better than gsr tb

 

Sup Manpaul

ITR tb will work great for your setup, maybe 64mm but thats it. Stage 3 cams are ideal for peak power around 8-8500, if you want to rev higher go with the bc4's. We'll be talking soon

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LsVtec92Hatch &raquo;</TD></TR><TR><TD CLASS="quote">Sup Manpaul

ITR tb will work great for your setup, maybe 64mm but thats it. Stage 3 cams are ideal for peak power around 8-8500, if you want to rev higher go with the bc4's. We'll be talking soon </TD></TR></TABLE>

I agree, even if you go with the BC4's. 64mm-65mm max, but tapered.

 

i've got some new BC III cams for sale... PM me for details...

 

aight well in that ccase skunk2 throttle body brand new for sale... 295 picked up i paid 300 lol