For those who don't follow my facebook feed here is something in the works for 20V owners.
The Concept: This adapter pictured fits between the head and the intake manifold to tilt the whole thing up to a steeper angle. This will also let people run longer velocity stacks in their RWD AE or KE as they should go over the brake booster instead of right into the side. It's also to straighten out the inlet path which is explained below next.
The theory: On all three of the 4age 20v engines the intake manifold is bolted to the head on an angle instead of being inline relative to the port angle. Sure there is a bit of radius there but it's still a sudden angle change. This is why we can't look down an open throttle and see the valves inside at the very end. It's theorised that there's a laminar flow separation during this manifold to port transition which causes general turbulent and reduces the effective cross sectional area of the port.
Pics below the 3d model of the blacktop version is shown
(click to zoom)
Fitment: The base plate has it's top face machined at an angle. To clamp it to the head countersunk bolts are used at the top while the original fasteners can be used at the bottom. It has O-ring slots around each of the ports on both sides, so 8 x O-rings instead of gaskets. The top plate is flat and bolts to the bottom plate with bolts that fit in-between the other holes. This then lets an unmodified intake manifold and thermal gasket all bolt on as per usual.
Development process and testing: If all goes well I will get a blacktop head dropped off this weekend to borrow. This will let me confirm the port dimensions so I can have a good transition. So confirming/altering that side of things I also need to measure up and make a silvertop version. To make sure I have not overlooked something silly which happens pretty often I will get as much as will fit into the machine 3D-printed for both versions. The 200mm that the guy can print will be enough for me to bolt it up and test it out. From there one Silver and one blacktop version will be machined up the same as the final spec which will let me do testing. If there's a perceived a difference or possibly even if there isn't I will likely hire an hour of dyno time. On this dyno I would try with and without this adapter and then with the adapter using the longer 100mm velocity stacks.
Even if this doesn't make any extra power in itself I likely will go ahead with a batch on people giving a deposit, tilting the velocity stacks upright is enough reason alone to have this. So if the angle doesn't help then the longer stacks and filters would for sure.
Expected results: There is opposing opinions on this one in regard to the intake path. The owner of the workshop Yager Motorsport used to do this via head mods instead of an adapter and he reported gains even on stock engines. Others have said that it won't do anything, so hence this test, time to get the facts.
Timeframe: I would think I will have everything finalised and final test fitting done in about 3 weeks. From which I will get the prototypes made and then do testing. From this I would say add another 3 weeks or so before requesting deposits, another week to give people time to put their request in and then production begins. So all up maybe 7 weeks for pre-orders and 10 for the final release.
Price: These are likely to be $190 + bolts and O-rings for those who put a deposit down. This may go up to $220 later. Bolts and O-rings might be $10 all up, yet to confirm as there is a lot of them and I don't know for sure. I will confirm all details later before accepting any money.
Feedback / thoughts anyone?