RLD Performance Racing Parts and Services

RLD Performance LS7 cylinder head program meets or beats the competition every time.  These are serious racing heads.  These heads are sold as new GM CNC castings which are further CNC modified for increased flow.  We can use factory or specified parts.  Customers may send their new parts to us or we can quote them our GM price.  There are two port development options available at this time.  The premium CNC/polished intake port flows 401 CFM (49 CFM or 14% more than the GM CNC port).  The exhaust port flows 281 CFM (69 CFM or 27% more than the stock GM CNC port).  With CNC modifications to the factory LS7 head, our full race cylinder head flows 49 CFM more than factory and the exhaust flows 60 CFM more than factory with a very much improved E/I ratio.

The stock GM manifold flows a peak of 347 CFM at .650 lift or within 87% of max flow of the modified intake port or within 99% of the stock intake port.  We now have new dual springs most applications.  These heads are built to order per the customers requests.

We also have a Crower racing 1.8 stainless steel roller rocker arm shaft system available for the LS7 and L92.  The LS7 heads must be machined in order to use this system.  Due to the complexity of the machining process, we only recommend that a machine shop perform this operation or you may accidentally ruin your LS7 heads.

All airflow data is corrected data (Temperature and Atmospheric Pressure) at 28" of water.  Intake is measured with a shaped entry and the exhaust is measured with a stub pipe.  Polishing the runners adds about 6-7 CFM average through the port.

Combustion Chamber=70

Runner = 270   85

Valve=    2.20  1.61

Note-Max flow through stock intake manifold =347CFM

RLD CNC LS7     Vs    Stock GM CNC LS7 Ports

Lift     I      E    E/I             I      E    E/I      

.100   81   61   75%           71    50  70%

.200  172  122  71%          145  120  83% 

.300  252  189  75%          222  158  71%

.400  314  236  75%          271  192  71% 

.500  353  262  74%          315  207  66%  

.550  366  268  73%          332  214  64%       

.600  376  272  72%          348  219  63% 

.650  386  276  72%          350  220  63%

.700  390  281  72%          352  221  63% 

.750  393  281  72%           NA  NA                    
AVG  308  225  73%         276  186  67%