20B NA BP semi-PP ITBs
Made some progress so far.
Oil pan modified, steering rack de-powered and cleaned up, and radiator mounts moved lower.
I am trying to fit this motor with minimal mods possible. Because I am doing a custom intake, I can afford the engine to be a little higher than a stock intake requires, obviously lower is better, but for a street driven car, Im sure the height I will get it down to will be suitable.
Oil pan modified, steering rack de-powered and cleaned up, and radiator mounts moved lower.
I am trying to fit this motor with minimal mods possible. Because I am doing a custom intake, I can afford the engine to be a little higher than a stock intake requires, obviously lower is better, but for a street driven car, Im sure the height I will get it down to will be suitable.
Yeah, I'm stuck on length though. Any ideas? I know that its going to be stab at length anyways and dyno time is the only way to tune it's length but,
I was planning on going long, however I'm under the car at the first gearbox crossmember and I'm up to 48inches. I will be using a merge collector and 400mm long resonator, so I will only be able to get around 70inches or so.
Any thoughts?
I was planning on going long, however I'm under the car at the first gearbox crossmember and I'm up to 48inches. I will be using a merge collector and 400mm long resonator, so I will only be able to get around 70inches or so.
Any thoughts?
Last edited by F1Pilot; Mar 21, 2012 at 11:57 PM.
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
Granted, I don't know a lot about manifold design, but is that sharp turn exiting the flange of your rear rotor going to possibly effect performance?? I'd think you want them all to exit straight (at least for a inch or two) before beginning your bend? Thoughts?? Maybe it's just the angle of the photo??
Apparently about 3inches straight is best. But that wasn't going to happen for me. It isn't straight, but it's no where near as bad as it looks in the photo. It is pretty much identical to the second rotor.
Not the best but looking through the exhaust side it doesn't look too bad.
Not the best but looking through the exhaust side it doesn't look too bad.
Not too sure. As long as I can, probably starting around 70 inches or so.
PP housings are finished. A work of machining art once again by Xtreme rotaries. I will post pics when I can.
PP housings are finished. A work of machining art once again by Xtreme rotaries. I will post pics when I can.
Yeah, I'm stuck on length though. Any ideas? I know that its going to be stab at length anyways and dyno time is the only way to tune it's length but,
I was planning on going long, however I'm under the car at the first gearbox crossmember and I'm up to 48inches. I will be using a merge collector and 400mm long resonator, so I will only be able to get around 70inches or so.
Any thoughts?
I was planning on going long, however I'm under the car at the first gearbox crossmember and I'm up to 48inches. I will be using a merge collector and 400mm long resonator, so I will only be able to get around 70inches or so.
Any thoughts?
I wont be much help to you here because my engine is still on stock ports. I currently have 36" primaries with a self fabed merge collector and megaphone with 3" tubing all the way back. I'm trying to reach maximum efficiency with stock ports. No dynos as of yet.
Heres some pics of the PP housings.
They are actually alot more involved than they look. The insert is still threaded and is still mated to a flat surface on the inside of the water jacket. If you look at a housing, you will see that you cannot mate it up flat if you come straight in like mine look. The inserts had to have been put in on an angle then machined down.( or something like that! lol). To give an idea, apparently each piece of aluminium started nearly 200mm round!!! This design allows a flange plate that bolts to the standard face to be used, instead of mounted on an angle as is the standard PP. The insert is large and allows the customer to change the shape of the port if they want. It is based around the MFR PP timing, so mine being around 44mm will open a bit after and close a bit before the MFR timing.

They are actually alot more involved than they look. The insert is still threaded and is still mated to a flat surface on the inside of the water jacket. If you look at a housing, you will see that you cannot mate it up flat if you come straight in like mine look. The inserts had to have been put in on an angle then machined down.( or something like that! lol). To give an idea, apparently each piece of aluminium started nearly 200mm round!!! This design allows a flange plate that bolts to the standard face to be used, instead of mounted on an angle as is the standard PP. The insert is large and allows the customer to change the shape of the port if they want. It is based around the MFR PP timing, so mine being around 44mm will open a bit after and close a bit before the MFR timing.

Made some additions to the sump. Put a couple of lateral trap doors in, hoping to stop any chance of oil/air scavange if I ever get this thing around the track.
Vid of the sump trap doors. Hopefully will prevent any oil starvation during lateral Gs.
http://www.youtube.com/watch?v=9Q7Xgf_dTrE
I don't like the reduced oil capacity of the modded sump though, and am thinking of adding a "heat sink transmission cooler across the fron to joing the 2 RS oil coolers which will add about 1L of oil.
Also thinking of making up a alloy cylinderical type of oil tank along side the engine (instead of the oil line) which should add another 2L or so.
Thoughts?
Vid of the sump trap doors. Hopefully will prevent any oil starvation during lateral Gs.
http://www.youtube.com/watch?v=9Q7Xgf_dTrE
I don't like the reduced oil capacity of the modded sump though, and am thinking of adding a "heat sink transmission cooler across the fron to joing the 2 RS oil coolers which will add about 1L of oil.
Also thinking of making up a alloy cylinderical type of oil tank along side the engine (instead of the oil line) which should add another 2L or so.
Thoughts?
Well got most my oil lines completed.
Used AN-8 everywhere, and relocated the oil filter to a remote mount upsidedown.
It turned out real nice, in that now it uses a large capacity oil filter and the filter position is such that I can change it through the gap in the subframe.
I did away with the idea of running an inline resevoir, but I will use the heat sink style cooler across the front to join the 2 coolers.
This along with the large capacity oil filter would have the system capacity back to around stock level.
Used AN-8 everywhere, and relocated the oil filter to a remote mount upsidedown.
It turned out real nice, in that now it uses a large capacity oil filter and the filter position is such that I can change it through the gap in the subframe.
I did away with the idea of running an inline resevoir, but I will use the heat sink style cooler across the front to join the 2 coolers.
This along with the large capacity oil filter would have the system capacity back to around stock level.







