magnumP5's RX-7 Build Thread
- Thread starter magnumP5
- Start date
Of course, makes sense for an oil cooler. My brain isn't working this week. I can see how it would add downforce. Air that would otherwise be going into the engine bay (and then under the car) or under the car is now being drawn out and over it.
I am putting on a new fiberglass front bumper on the car and I am going to split the grill opening. I will lay the oil cooler down and duct it out of the bottom of the car and duct the rest of the air thru the rad. I will leave some play in the hood pins so that as the hood will raise up a bit and allow the pressure under the hood to escape. laying down the oil cooler allows more air to get to the rad.
The painting looks great on the engine and parts hope you will be on the track in the spring.
Why not go with a ducted hood rather than loosening the pins? None available for the SA chassis?
That's similar to an idea I was entertaining for a bit. I wanted to lay the oil cooler down and in essence make a "v-mount" with the radiator. I quickly found out with the radiator in the stock location this would put the oil cooler lower than the front crossmember (about 3" off the ground). I'm still going to move the oil cooler about 2" lower so its bottom is even with the bottom of the radiator and removing the foam seal at the same time. This gets rid of a 20 mm x 500 mm obstruction from the radiator. I'm also cutting out all the spars and crap from the bumper for the least airflow obstruction as possible.
You learn something new everyday...
Long, rambling post ahead! If you don't feel like reading, skip to the end.
[Rambling]
I discovered and fixed something yesterday that would have made my life miserable and possibly have disasterous consequences. Here's a little lesson on rotary engines:
Everyone knows Mazda's rotary engines inject a small amount of oil into the combustion chamber to lubricate the seals. This is done via a "metering oil pump" or MOP and oil injectors. In my car the MOP is electrically-controlled but driven by a gear on the front of the eccentric shaft via a small drive shaft. People delete the MOP for various reasons even though it's a useful device. I removed mine but because it was an eletrically-controlled unit and my Haltech ECU can't control it. When most people delete the MOP they cap it off with a block-off plate. When doing this most leave the drive shaft for the MOP in place. I also removed the drive shaft because I didn't want something spinning away for no reason. What I discovered yesterday was this creates a bypass that could lead to low oil pressure issues. Reference the picture below:
This is the back of my front cover. The little hole above the third bolt hole on the right is actually the port for the oil supply to the MOP. The raised bulge in the casting the travels diagonally down and then to the right from this port is the path the oil takes. Where this ends (the cylinder-looking thing) is where the drive shaft for the MOP originally was. The block-off plate on the outside of the front cover prevents any oil from shooting out of the front cover but you can now see how oil would just spray out into the front cover and drip back into the oil pan. I'd argue even with the MOP drive shaft in place you'd have this problem but probably to a lesser extent. Either way I'd imagine this would lead to decreased oil pressure in the engine, which is bad.
My solution was to plug the port so no oil can make it to the space formerly occupied by the MOP drive shaft. The best option seemed to be to run a tap into the port and plug with a set screw. Lucky for me the hole was perfectly sized for a M6 plug so I could use a spare M6 x 1.00 mm set screw I had left over from my engine bay hole-plugging job. One set screw and some grey silicone sealant and this is the end result:
This should eliminate any possibility of leaks through the MOP block-off plate and more importantly keeps an unecessary leakage path from droppping oil pressure. Thanks for reading my little PSA.
[/rambling]
So if you didn't read all that in short I saved myself a pain in the ass by plugging an oil port in the front cover I missed. If left open it would've led to low oil pressure, which would've required me to remove the front plate after discovery to fix if it didn't cause my engine to fail in the first place.
Last night I moved the oil cooler down by ~1 inch to get more air to the radiator. Since everything is being ducted I'm not worried about air not reaching it. I also started painting the intake manifold (last piece, I believe) since the weather's nice. Tonight's plans are to continue painting the IM and to make new supports for the front of the custom undertray (since I pulled all the stock pieces - air restrictions) and lowered oil cooler.
Long, rambling post ahead! If you don't feel like reading, skip to the end.
[Rambling]
I discovered and fixed something yesterday that would have made my life miserable and possibly have disasterous consequences. Here's a little lesson on rotary engines:
Everyone knows Mazda's rotary engines inject a small amount of oil into the combustion chamber to lubricate the seals. This is done via a "metering oil pump" or MOP and oil injectors. In my car the MOP is electrically-controlled but driven by a gear on the front of the eccentric shaft via a small drive shaft. People delete the MOP for various reasons even though it's a useful device. I removed mine but because it was an eletrically-controlled unit and my Haltech ECU can't control it. When most people delete the MOP they cap it off with a block-off plate. When doing this most leave the drive shaft for the MOP in place. I also removed the drive shaft because I didn't want something spinning away for no reason. What I discovered yesterday was this creates a bypass that could lead to low oil pressure issues. Reference the picture below:
This is the back of my front cover. The little hole above the third bolt hole on the right is actually the port for the oil supply to the MOP. The raised bulge in the casting the travels diagonally down and then to the right from this port is the path the oil takes. Where this ends (the cylinder-looking thing) is where the drive shaft for the MOP originally was. The block-off plate on the outside of the front cover prevents any oil from shooting out of the front cover but you can now see how oil would just spray out into the front cover and drip back into the oil pan. I'd argue even with the MOP drive shaft in place you'd have this problem but probably to a lesser extent. Either way I'd imagine this would lead to decreased oil pressure in the engine, which is bad.
My solution was to plug the port so no oil can make it to the space formerly occupied by the MOP drive shaft. The best option seemed to be to run a tap into the port and plug with a set screw. Lucky for me the hole was perfectly sized for a M6 plug so I could use a spare M6 x 1.00 mm set screw I had left over from my engine bay hole-plugging job. One set screw and some grey silicone sealant and this is the end result:
This should eliminate any possibility of leaks through the MOP block-off plate and more importantly keeps an unecessary leakage path from droppping oil pressure. Thanks for reading my little PSA.
[/rambling]
So if you didn't read all that in short I saved myself a pain in the ass by plugging an oil port in the front cover I missed. If left open it would've led to low oil pressure, which would've required me to remove the front plate after discovery to fix if it didn't cause my engine to fail in the first place.
Last night I moved the oil cooler down by ~1 inch to get more air to the radiator. Since everything is being ducted I'm not worried about air not reaching it. I also started painting the intake manifold (last piece, I believe) since the weather's nice. Tonight's plans are to continue painting the IM and to make new supports for the front of the custom undertray (since I pulled all the stock pieces - air restrictions) and lowered oil cooler.
Dropped another $1500+ on parts. I think that's the last of the "big" parts except a passenger's seat and harnesses. This build has gotten so out of hand it's starting to no longer be funny. Welding in new seat supports, rebuilding the fuel system, RX-8 parts, balancing the engine, custom undertray and ducting, and now studding the engine. None of these things were even in my mind back in April '11.
My camera/phone doesn't seem to want to take pictures anymore so I need to figure something out otherwise this will become a very boring thread.
My camera/phone doesn't seem to want to take pictures anymore so I need to figure something out otherwise this will become a very boring thread.
roy obanion
Member
- :
- 02 p5, 95 miata
It will be so worth it, trust me. (I know you know that)
The "if I don't do it now, it won't ever get done" mentality is killing me. I forgot to list out the parts I purchased yesterday:
OEM Clutch Slave Cylinder
Braided SS Clutch Line
Upgraded Clutch Disk
Upgraded Clutch Pressure Plate
Aluminum Flywheel
New OEM main pulley bolt crush washer
Short OEM tension bolt
Long OEM tension bolt
Engine stud kit
Oil Pan Baffle
OEM oil cooler mounts
Plugs for stock primary injector ports
Upgraded oil pressure regulator
Braided SS oil cooler lines
OEM intake manifold gasket
I've got the appropriate rear counterweight already. I purchased that because it was needed to balance the engine a while back. The flywheel is balanced to itself.
I went with the Racing Beat "Street" OPR. I know it's like $60 more expensive but the more I read about the FD regulators the more issues I seemed to find with high oil pressure - like people seeing over 60 psi at hot idle. I don't have a turbocharger and only have one oil cooler and I'm keeping its thermostat and the check ball on the eccentric shaft so I really don't think I need a regulator that bypasses at 110 psi.
Not problems per se, just REALLY high oil pressure. Some people have reported blowing out the o-ring in the front cover but that seems to be rare. I just don't see the need to have 100+ psi of oil pressure unless you've got multiple auxilliary systems (multiple oil coolers, turbos, etc.) and are running some large jets on the eccentric shaft. As long as I still see 60+ psi of oil pressure while on track I'll be happy. If the RB street OPR doesn't get me there I'll look into the FD one. Not likes it's that hard to replace or anything.
Not sure I'm familiar with that one. My front iron has the "old style" casting so there's only room for the o-ring and I can't use the plastic spacer thing. I'm going to use some Hylomar to hold it in place. Also I'm not going to use a front cover gasket but just RTV to get a little more compression on the o-ring. TitaniumTT on the other forums is one person I know of having the o-ring issue.
mymmeryloss
Member
- :
- 13bT Mazda B2600i
Money money!
Coming right along!
Coming right along!
Not much in the way of progress (more on that later) but here's some pictures of parts to hold you people over!
New tension studs. 16 total, 2 shown:
They conveniently have a hex keyway machined into the top for ease of install:
Racing Beat oil pan baffle. This should prevent any oil starvation issues on track.
Racing Beat primary fuel injector plugs. Since my injectors are mounted in the TB I need to block off the ports for the primary runners in the center intermediate housing.
Here's an idea of how they look installed:
I'm not really happy with the "brace" piece but that's what I get for ordering OTC pieces. I probably can leave that peice off since I'm N/A there will only ever be vacuum applied to the plugs so there shouldn't be any risk of them popping out. At the very least I'll make my own "brace." Also debating if I should paint these black or silver to make them stand out less. Either way the plugs themselves still need some work:
The bottoms of the plugs extend slightly into the path of the intake ports. Easily fixed by 5 minutes on the grinder.
Here's the uber-expensive Racing Beat "street" adjustable oil pressure regulator:
It supposedly bypasses at 80-85 psi, but I need to figure out how exactly the adjusting part works.
SS clutch line (yep, it's a hose):
Some more hoses; braided SS oil cooler lines from Mazdatrix. After working with 6 AN for a while these seem huge (10 AN)!
Racing Beat 7 lb aluminum flywheel and hardware:
Upgraded clutch disk and pressure plate (Exedy):
Here's my attempt to show the clutch disk has no "cushioning spring." This is what "engaged but not quite engaged" feeling comes from. It's still a sprung disk so there's some forgiveness.
Finally, here's why I haven't been able to work on the car too much lately:
Ian James Frankenfield. Born 10/26/12 at 12:01 PM. 8 lb 9 oz, 21.5 in. It's hard to think about the RX-7 with this little guy around!
New tension studs. 16 total, 2 shown:
They conveniently have a hex keyway machined into the top for ease of install:
Racing Beat oil pan baffle. This should prevent any oil starvation issues on track.
Racing Beat primary fuel injector plugs. Since my injectors are mounted in the TB I need to block off the ports for the primary runners in the center intermediate housing.
Here's an idea of how they look installed:
I'm not really happy with the "brace" piece but that's what I get for ordering OTC pieces. I probably can leave that peice off since I'm N/A there will only ever be vacuum applied to the plugs so there shouldn't be any risk of them popping out. At the very least I'll make my own "brace." Also debating if I should paint these black or silver to make them stand out less. Either way the plugs themselves still need some work:
The bottoms of the plugs extend slightly into the path of the intake ports. Easily fixed by 5 minutes on the grinder.
Here's the uber-expensive Racing Beat "street" adjustable oil pressure regulator:
It supposedly bypasses at 80-85 psi, but I need to figure out how exactly the adjusting part works.
SS clutch line (yep, it's a hose):
Some more hoses; braided SS oil cooler lines from Mazdatrix. After working with 6 AN for a while these seem huge (10 AN)!
Racing Beat 7 lb aluminum flywheel and hardware:
Upgraded clutch disk and pressure plate (Exedy):
Here's my attempt to show the clutch disk has no "cushioning spring." This is what "engaged but not quite engaged" feeling comes from. It's still a sprung disk so there's some forgiveness.
Finally, here's why I haven't been able to work on the car too much lately:
Ian James Frankenfield. Born 10/26/12 at 12:01 PM. 8 lb 9 oz, 21.5 in. It's hard to think about the RX-7 with this little guy around!
roy obanion
Member
- :
- 02 p5, 95 miata
Congrats, buddy! 
