when reading the compression charts for LS/vtec I was a little puzzled...
is it true that by using a b18b1 block w/ stock internals and adding a b18c5 head you actually lose compression?? if so.... does this mean the only way to get good power out of this set-up is to build up the whole block???


if this has been covered already i apologize...i must have missed it

 

You do NOT want to use the stock bottom end when building an ls/vtec.

An ls/vtec with a b16 head and a stock bottom end will make about 9.6:1 c/r which is not enuff to make any decent power IMO.

You need to be at about 10.8:1 to 11.5:1 to make decent power

I personally run about 11.6:1 c/r on my setup.

To make a higher c/r you need to run ITR/CTR/p30 pistons etc.

Check out:
http://www.c-speedracing.com/howto/c...c/compcalc.php

http://www.c-speedracing.com/howto/lsvtec/lsvtec.php

My setup:
http://www.phearable.net

Note: Use all new bearings/seals/pumps/belts when doing a build to make it last a long time

 

so basically i have no business...(cost wise) attempting this set-up, despite how bad-azz your's is... it would cost me a small fortune to get up to speed with everything i would need... love the idea .. hate the price.... I think i would be better by buying a jdm type R full swap for 4k and selling my full swap for as much as possible

 

That is correct....
Ls/vtec motors done right cost an arm & a leg.
On average:
$800 in honda parts including pistons
$50 on rod bolts
$250 for machine work (cleaning, rod bolts, piston mod, flywheel resurface)
$1k on your cyl head (b16 head, valve springs, itr cams etc.)
$300 for the ls shortblock
$150 for ls/vtec conversion parts such as line kit & dowels etc...
$200 for a ITR or Aebs intake manifold.

Total cost: $2500-3k plus clutch & tranny (you will want a b16/gsr/itr tranny & a decent clutch).

The list can go on... depending on what you have or dont & what you want :-/

I personally could have spent more by purchasing a block girdle & new oil pan/windage tray & oil pick up etc.. But I opted not to because I didnt want to spend another $500 for mods that I probably wasnt going to use on my daily driven motor.

 

true.. good info.. i think i'm going to try to sell my car and just buy a type R.... i haven't been able to find spec differences on jdm vs usdm type R... do you happen to know where i can find them?? our do you know are there big differences?

 

The jdm spec pistons make a little more compression.

11.1:1 c/r on a jdm b18cR motor
10.6:1 c/r on a usdm b18c5 motor

Also the 98+ spec trannys have a better final drive but the 4th & 5th gear supposedly better on the pre 98 trannys according to spoon

 

Kieth preffers forced induction to a b18c1 via JRSC lol

 

well is a 2001 type R a usdm spec?? may sound dumb..but i don't know..... if so is the pistons really only difference??

 

Pistons & tranny & cam specs thats about it.
The differences are not enuff for the average joe to notice.

Use google.com to do some reasearch

If you are ordering a complete jdm itr swap, I recommend you talk to Steve at hmotorsonline.com he is a good guy