During the development stage, Trick Flow engineers determined that
the valve angles needed to change from 15* to 13.5*. This change 
decreased valve shrouding,increased mid-lift airflow,and increased 
rocker arm-to-valve cover clearance.Testing also proved that relo-
cating the spark plug position in the combustion chamber further
enhanced combustion along with mid lift airflow and improved the 
integrity of the casting in the chamber area. Trick Flow also added
additional material to the decks (.600") and to the rocker arm 
mounting pads to improve high rpm valve train stability. 

These new fully CNC-ported heads feature 215cc intake runners,
80cc exhaust runners,64cc combustion chambers,2.040" intake valves,
1.575"exhaust valves,bronze valve guides,and ductile iron intake
and exhaust seat inserts.

Assembled heads come equipped with stainless steel intake and
exhaust valves, 1.300"dual extreme pressure (150# seat 450# open)
valve springs for lifts up to .650",viton seals,machined spring 
locators, 7 degree titanium retainers and machined steel locks.

One last important feature of this 13.5* head design is the valve
drop.This head features a .155" valve drop on the intake, a stock
5.7 head with 2.00" valves has around .150". What this means is you 
can run this head on stock pistons with large camshafts and still
have more piston to valve clearance than a stock head and also 
more compression.


Note:Flow numbers are based off of an average of 5 heads tested.
All flow numbers are tested on a 3.900" fixture @28"h20, using
clay intake radius,and a 4"x 1-7/8"pipe on exhaust.