4-Rotor FC Build
Junior Member
Joined: Dec 2010
Posts: 18
Likes: 0
From: Tucson, AZ
I just spent about 6 hours of my life catching up on this build... all 57 pages. John I just want to say congrats. This is absolutely fantastic work, and thank you for the documentation. hard to find good documentation of builds like this. I'm really looking forward to seeing the finished product!
Thread Starter
Joined: Oct 2010
Posts: 605
Likes: 13
From: The Netherlands
Thanks everyone 
Well, it's never going to be complete
I'm already thinking about things I'm going to do when the car is up and running! But a time idea for a first startup is pretty hard to say, Probably got about 4-6 weeks of work to do before startup.
Anyway, the transmission is mated with the engine:
So I planned to mount the engine in the car, but looking at all the stuff that still needs to go on the engine I realised that my life would be so much easier if I finish the engine on the workbench, and install it in the car when it's complete with the intake, exhaust, wiring loom and all the other stuff.
First thing I started messing with is the slide-intake which still needed some work. I previously made a slide throttle that uses a sliding teflon piece to open and close the intake ports. Although it might work, using a sliding teflon part isn't the best way to do it. The engine vaccuum will suck the teflon piece against the aluminium causing the throttle to be heavy to operate. It can also cause the trottle to lock up in an open position. So I started fabricating something that uses ball bearings. It's a similar plate than the old teflon one, but it's made from 6060 alloy, and I'll add ball bearings to make the motion smooth. Already machined most of the new throttle plate. I'll add the bearings tomorrow.
Well, it's never going to be complete
I'm already thinking about things I'm going to do when the car is up and running! But a time idea for a first startup is pretty hard to say, Probably got about 4-6 weeks of work to do before startup.Anyway, the transmission is mated with the engine:
So I planned to mount the engine in the car, but looking at all the stuff that still needs to go on the engine I realised that my life would be so much easier if I finish the engine on the workbench, and install it in the car when it's complete with the intake, exhaust, wiring loom and all the other stuff.
First thing I started messing with is the slide-intake which still needed some work. I previously made a slide throttle that uses a sliding teflon piece to open and close the intake ports. Although it might work, using a sliding teflon part isn't the best way to do it. The engine vaccuum will suck the teflon piece against the aluminium causing the throttle to be heavy to operate. It can also cause the trottle to lock up in an open position. So I started fabricating something that uses ball bearings. It's a similar plate than the old teflon one, but it's made from 6060 alloy, and I'll add ball bearings to make the motion smooth. Already machined most of the new throttle plate. I'll add the bearings tomorrow.
Thread Starter
Joined: Oct 2010
Posts: 605
Likes: 13
From: The Netherlands
On a side note, look at what happened to my daily driver bmw today
Looks like the car got jealous about me spending all my time on rotaries and commited suicide. This happened on the freeway at 75mph, sounded pretty scary! A few connecting rods failed, Good thing my rotaries don't have those
Joined: Mar 2001
Posts: 31,835
Likes: 3,233
From: https://www2.mazda.com/en/100th/
Well I'm sure that with a good tune and these mufflers it can drive around without setting the neighbourhood on fire and waking up the dead, but it will never be a daily driver. I'm not really sure yet if it's going to be track only or not. It will probably be track only at first, and if everything seems to be reliable and tame enough maybe I can try to get it tech inspected and registered on the road, but that's a really big if!
however mine does indeed wake the dead, they told me it was keeping them up, and B, its a happy little engine, and it wants to run free. i'm sure i could drive it in traffic, but it wouldn't be happy there.
Thread Starter
Joined: Oct 2010
Posts: 605
Likes: 13
From: The Netherlands
this is speculation, my P port is a happy little engine, it actually drives really nicely with a carb, so i'd actually expect yours to be better, which would put it in the drives like stock area.
however mine does indeed wake the dead, they told me it was keeping them up, and B, its a happy little engine, and it wants to run free. i'm sure i could drive it in traffic, but it wouldn't be happy there.
however mine does indeed wake the dead, they told me it was keeping them up, and B, its a happy little engine, and it wants to run free. i'm sure i could drive it in traffic, but it wouldn't be happy there.
, You're probably right about the noise, looking forward to find out how bad it is though , I haven't found the bottom part of the piston yet. If you stand on the left side of the engine bay it's actually possible to look through the engine block and see the right side motor mount Things got pretty crazy in there! Anyway, work continues on the engine little by little. The sliding intake really takes far longer than I ever thought it would. It looks simple, but I've probably got over 50 hours in that thing and it still isn't done
. Good news is that the aluminium sliding plate with the bearings works great! Motion is perfectly smooth now, it doesn't bind or anything. I'm confident this will work perfectly, just need to add 6 more bearings (only had 10 bearings here, but the slide plate uses 16 of them), and I need to add the TPS sensor, and it needs an idle adjustment screw. Probably another evening of tinkering with it before I can finally move on.Shows the guiding bearings. Because the sliding plate is so long I'm using 16 bearings to keep everything supported. This is needed because the slide throttle will be pulled to the engine because of the engine, this pulling force is about 47kg's, or 104 pounds for the imperial guys
Joined: Mar 2001
Posts: 31,835
Likes: 3,233
From: https://www2.mazda.com/en/100th/
less intake vacuum = less exhaust gas on the overlap cycle = better driveability.
Well I'm sure that with a good tune and these mufflers it can drive around without setting the neighbourhood on fire and waking up the dead, but it will never be a daily driver. I'm not really sure yet if it's going to be track only or not. It will probably be track only at first, and if everything seems to be reliable and tame enough maybe I can try to get it tech inspected and registered on the road, but that's a really big if!
On a side note, look at what happened to my daily driver bmw today
Looks like the car got jealous about me spending all my time on rotaries and commited suicide. This happened on the freeway at 75mph, sounded pretty scary! A few connecting rods failed, Good thing my rotaries don't have those
On a side note, look at what happened to my daily driver bmw today
Looks like the car got jealous about me spending all my time on rotaries and commited suicide. This happened on the freeway at 75mph, sounded pretty scary! A few connecting rods failed, Good thing my rotaries don't have those
How will you synchronize the rotors with that slide throttle? For example, if the clearance between the plate and the housing increases from rotor 1 to rotor 4 due to tolerances; rotor 1 may barely want to idle and rotor 4 may be wanting to take off. I suppose good tolerances would solve that problem though.
