| Been working on these babies since the beginning of the year - countless hours of CAD work, flow simulation, flowbench testing, and this is the result. At this point the foundry is a go on producing the tooling and manufacture of a batch of these units. The final kit will come with the head and turbine gaskets, new fasteners, and a new dipstick tube (not shown). The new route for the tube will come between the #2 and #4 runner and use the OEM dipstick. These manifolds DO NOT REQUIRE CUSTOM DOWNPIPES.
There is a minor amount of shaving necessary at the small bosses on the head at the valve cover plane but it took no more than just a couple of minutes to carve those down. This is a small price to pay for the low profile design and the improved flow characteristics of these manifolds. The two rear studs must be replaced with shorter pieces for proper fitment and those will come with the kits. These manifolds will fit everything from stock turbos up to GT30 turbochargers. GTX30 turbos will also fit but I will have to make a custom set for you as that turbo is not available with a T2 turbine flange housing - I have produced many sets of GTX30 turbos with a T2 turbine flange housing. GT30 sized turbos will require a little massaging to the passenger framing rail, not much, but about 1/8" of space needs to be made. I did not want to reorient the turbo on that side to make it fit as it would require custom downpipes. Flowtest results for the new manifold design.
Driver Front: 279.3 cfm
Driver Center: 284.7 cfm
Driver Rear: 281.5 cfm
Passenger Front: 284.4 cfm
Passenger Center: 286.5 cfm
Passenger Rear: 285.7 cfm
Maximum deviation between any two cylinders: 7.2 cfm, 2.6%. Mike Smith manifolds:
Driver Front: 241.6 cfm
Driver Center: 237.1 cfm
Driver Rear: 238.6 cfm
Passenger Front: 219.1 cfm
Passener Center: 231.1 cfm
Passenger Rear: 228.1 cfm
Maximum deviation between any two cylinders: 19.5cfm, 7.2%. Total average flow of AshSPEC manifolds: 283.7 cfm
Total average flow of MS manifolds: 232.6 cfm
Percentage gain in flow of AshSPEC manifolds: 22% At this point we expect to have the shipment in a little over two months and have arranged with the manufacturer to have them produce 10 sets as soon as the tooling is made which will be sent in advance of the main batch order. Those will arrive to us within 45 days from now. At the moment three of those are already reserved so I have 7 sets remaining for the pre-order. If you are interested in the pre-order, please email me and this will be done on a first come first serve basis. The pre-sale price is $800 plus shipping. My email is ash@ashspecz.com. In addition, now that there is plenty of room for large turbo inlet pipes we will be releasing a full 3" turbo inlet kit made for these exhaust manifolds. Those kits will be available around the same time the large batch order of the manifolds are ready and we will likely run a pre-sale on those too as soon as they are complete. 
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Enthusiasts soon understand each other. --W. Irving.
Are you an enthusiast? If you are out to describe the truth, leave elegance to the
tailor.
Albert Einstein
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AshSPEC Low Profile High Flow Cast Iron T2 Exhaust Manifolds - 
