BoostinDC2

is there a difference besides the bigger ports. i hear the lost motion assembly is alot better but can anyone verify that?

3rdShift.org

I am under the impression that the heads are very structurally and geometrically similar. The stock valvetrain of the typeR head is obviously stiffer and ready to handle more revs... but valvetrain does not *make* power, so in theory each head ported similarly w/ the same cams & revving to the limit of the latter should make similar power.

Looose_R

both are p30 cast heads, itr's however reciever mild pocket ports.

Jared

Actually, both are the PR3 casting. ITR is ported to smooth flow in higher RPMs and better flow down low. ITR uses different cams, valve springs, retainers, and LMAs.

BoostinDC2

so the LMA's are different. whts the difference in the LMA's?

bb6h22a

..are shorter in the Type R head than in the regular b16 head. But, I have read of people using itr/ctr cams in b16 head w/b16/gsr LMA's w/out incident.
But, if your doing anyway, why not do it all.
Also, the head is different than the b16 in the following ways:
Port and polish job on the head valve seat angle is 45 degress vs. 60, different valves smaller stem radius w/ larger cone also 12% lighter, intake manifold, valve springs, LMA's, cams, all in all the mass of the valvetrain has been redueced dramatically as well as the inertia of the valvetrain, not as much as roller rockers would, but better than tapets..
If you want to read more about the changes made to the R motor as a whole here is a fairly comprhensive article:
http://integra.vtec.net/carboy.html
Hope that helps........


[Modified by bb6h22a, 7:02 PM 9/18/2001]

rainforest

lma lost motion assemblly.
lighter valve train = free horsepower so it does do a little. every thing counts.

BoostinDC2

is there a difference in the weight of the rocker assembly

BoostinDC2

think its worth changing most of the parts to ITR? im just trying to build a turbo head and will rev out to 9-9500.

bb6h22a

...as far as the 9-9.5K why? Is this a street or race car? Also, beating the **** out of your car like that consistently will quickly erode reliability. However, when I talked to the mechanics for the Realtime ITR's they swore that they revved the cars to 9k all day long on oem itr valvetrain, so you may be ok w/ it? Who knows..
But, you might want to look into Ti retainers and even stiffer valvesprings, something along the lines of Portflow, Toda, Mugen, etc.
If your trying to get the head to flow better, changing the valvetrain, etc, isnt going to make it flow any better at all. The only thing that will change flow and the efficency of the head are the cams, valves, and the geometry of the head.
If you already have the b16 head, just contact either Portflow or AEBS and talk to them about what you want to accomplish, other things you should consider are thermal coating of the combustion chambers, as heat is the # 1 killer of turbo engines.
Honestly, if you get the right sized turbo, you wont need to spin your motor to 9k to make power, much the opposite, you want to be at full boost and the majority of your power after say 3k rpm..