The plenum base has integrated velocity stacks so theres no need to use those expensive pieces from Ross Machining. I've used Ross Machining velocity stacks in the past, and they work well, but require more cylinder spacing then the L28 affords.
Thanks for the Payment KJones. I will talk to the machinist hopefully tomorrow and get a final price on the plenum base. I've had a hard time catching him lately. I will post a shopping list for those building these manifolds.
Regards,
Justin