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Started on smoothing the intake port on the rear iron, I still need to copy this port onto a template so I can replicate it on the new (used) intermediate and front irons, but here are the results after just smoothing most of the roughness from the port (still some left that my dremel bits could not reach but i'll figure that out later) and now just needs to be polished.
I posted these pics on my facebook page and was questioned why I didn't round the edges off and i'm sure the question may rise here as well, so to answer that (and i've already said this before) I do not want to modify the port shape at all beyond just smoothing them out as I want the only improvements to this engine to be mainly from the renesis rotating assembly more than anything else (acceleration, economy, output, etc), but at the same time the exhaust ports are a different story as i'm using different housings with a better condition chrome surface (one of which has no exhaust sleeve and has been ported very large which the other stock port housing will be matched to). I'm not entirely sure out much the exhaust port size differences will affect output or economy, but for the sake of longevity is why they're being used.
Right now my main goal for this build is to have the engine built, dropped back into the car and ready to go before June when I have to drive down to Texas for ARMY ADOS orders (where i'll be for 4 months), or if I can't do that, i'll drive down with the 12A (which is running now and runs great btw) and have the engine in the back of the car in pieces so I can assemble and install down there
So I have a bit of bad news, nothing that will keep me from continuing the build, but just some thing that will delay it from happening as soon as I wanted it to. I will be leaving for Texas for ADOS orders from the ARMY on June 4th (report date June 6th), with that in mind there have been many delays with finishing the balancing on my rotors and counterweights to where I might have them back in about a week (or right before I leave, no idea tbh) and on top of that the housings still havent been sent off for resurfacing (reason being because I had to take care of some other things financially first). So I highly doubt that i'll be able to have this engine built, dropped into the car, running, driving and tuned before I leave, so i'm just going to finish up port and polish work here and just plan on building the engine down there (There's a DIY auto workshop on base so doing so wont be an issue).
I did make some progress on at least one thing though and that's porting the LIM for the tall ports in the center iron. I finally had enough of trying to use my cheap carbide and sanding bit set to port and polish and went to lowes and got one good carbide and one good sanding bit and they did phenominally better and the runners are now about where I want them The lines aren't perfect and there is alot of skipping because the shitty bit I was using weren't very easy to keep in one place, but the skipping marks will be resurfaced out and the imperfect lines should affect much.
Another thing I was looking into doing was upgrading to a renesis front cover metal gasket and widening the front cover oring port depression to accept a nylon oring to go with the metal gasket. The reason behind this is because I will be increasing oil pressure either by way of an adjustable shimmed old school regulator (the one this engine came with) or a squished renesis regulator and I want the oring area to be able to hold the increased oil pressure reliably. Link to DIY for renesis front cover gasket mod: RX7 Renesis Gasket Modification - Mazda RX8 Front Cover Metal Paper- Rotary
Don't squish your pressure regulator. That's crazy talk. Just get an FD reg if you need higher oil pressure. The adjustable ones are horribly overpriced compared to the FD one.
Don't squish your pressure regulator. That's crazy talk. Just get an FD reg if you need higher oil pressure. The adjustable ones are horribly overpriced compared to the FD one.
The FD regis much harder to find while RX-8 regs are easily accesible and have higher pressure anyway. The adjustable reg comes stock with my engine, ive had 3 and sold 2, just forgot where I put the 3rd one so the squished RX-8 reg is just a backup incase I can't find it. The RX-8 metal gasket idea came about because it can hold higher pressure reliably. If you want to hear some real crazy talk, I have a another build planned that i'm calling the "trash engine build", but that's for another thread.
The FD reg is $30 brand new from Mazda dealerships, or $40 if you go to Atkins (which reports over 700 units in stock)! FD reg is rated at 100-110psi, Series 1 RX8 regulator is rated at 60psi, with the system running nominally at 80psi - a lot less than an FD. This was clearly inadequate and Mazda redesigned the oiling system in the series 2. As such, the series 2 Renesis didn't have a rear regulator at all, with the system running nominally at 110-115psi.
If you have an adjustable one already, great. But I only mention the squished regulator mod because of the number of engines failures due to this modification, with another one reported on these pages very recently (I can find it if necessary).
The FD reg is $30 brand new from Mazda dealerships, or $40 if you go to Atkins (which reports over 700 units in stock)! FD reg is rated at 100-110psi, Series 1 RX8 regulator is rated at 60psi, with the system running nominally at 80psi - a lot less than an FD. This was clearly inadequate and Mazda redesigned the oiling system in the series 2. As such, the series 2 Renesis didn't have a rear regulator at all, with the system running nominally at 110-115psi.
If you have an adjustable one already, great. But I only mention the squished regulator mod because of the number of engines failures due to this modification, with another one reported on these pages very recently (I can find it if necessary).
Where are you getting this info? and which series FD are you talking about? Last I checked ther FSM for the FD was only 50PSI (@3,000 RPM), either way it's more money that I don't need to spend on a regulator that I can just squish and have the desired oil pressure with the reg I already have, just seems like a waste of money is all
All 1993-2002 FD RX-7s have the upgraded oil pressure reg. This is common knowledge and well documented by engine builders here, AusRotary.com, Atkins Rotary website, Racing Beat website etc etc.
The oil pressure test procedure in the FSM specifies MINIMUM 50psi at 3,000rpm, but this is a very low reading and does not reflect normal expected running conditions. If you look at the tech specs in the FSM (start of the lubrication system chapter) it lists the "regulator valve relief pressure" as being rated at 110psi (compared to 71psi for FC). Earlier FSMs don't list a minimum pressure - they give an expected range (eg 64-78psi for FC) which is doesreflect normal running conditions. I don't know why Mazda why so relaxed with their pressure test for the FD - it is a bit misleading by Mazda.
The main problem with the squish mod is that unless you install it into a test reg before putting it into the engine you have absolutely zero idea what pressure it is going to bypass at. $30 is cheap insurance on a critical point of the engine compared with a kamikaze modification.
All 1993-2002 FD RX-7s have the upgraded oil pressure reg. This is common knowledge and well documented by engine builders here, AusRotary.com, Atkins Rotary website, Racing Beat website etc etc.
The oil pressure test procedure in the FSM specifies MINIMUM 50psi at 3,000rpm, but this is a very low reading and does not reflect normal expected running conditions. If you look at the tech specs in the FSM (start of the lubrication system chapter) it lists the "regulator valve relief pressure" as being rated at 110psi (compared to 71psi for FC). Earlier FSMs don't list a minimum pressure - they give an expected range (eg 64-78psi for FC) which is doesreflect normal running conditions. I don't know why Mazda why so relaxed with their pressure test for the FD - it is a bit misleading by Mazda.
The main problem with the squish mod is that unless you install it into a test reg before putting it into the engine you have absolutely zero idea what pressure it is going to bypass at. $30 is cheap insurance on a critical point of the engine compared with a kamikaze modification.
Good point, i'll see if I can test one of my squished regs and see what the result is and if the resuklt is less than desireable then maybe i'll go for the FD reg. And I agree on mazda misleading with their FSM, I mean the FSM for the RX-8 says that 5W20 oil is perfectly fine to use in a rotary engine afterall lol
That looks pretty bad, but the reg also looks excessively squished as well seeing how short and flat the top is
That's an extreme example of the reg not bypassing at all, but I've seen other examples of ones that were putting out at 130+ psi resulted in a burst oil cooler lines and in one example documented on ausrotary.com, the oil filter seal blowing and engine spraying onto the exhaust causing a fire.
Just called to price check through mazda and an oil pressure reg for a 93 FD is over $60 and the RX-8's front cover gasket is $47, so looks like atkins is the best route to go for either
Just got my parts back from being silica blasted. I had this done because I wanted to have the cleanest surface possible for repainting and eliminate as much surface contamination as possible. The intake manifold is a good example because I had already painted it wrinkle black and surface contimination had ruined some of the finish. The rear iron, intake manifold and water pump housing will all be done in wrinkle black and the housings in bright yellow (i've already painted the front cover which came out great). I also still need to resmooth and straighten out the primary ports on the intake runners, but I thought it was kind of cool how it now looks like the tall ports were from the the racing beat factory cast now lol but i'm very happy that these parts now have a nice clean surface to paint on now
*And yes all parts will be thoroughly cleaned and cleared of any silica debris left behind
On another note, i've also decided to completely remove the OMP shaft seeing as it's pretty much just a useless extra gear for the eshaft to spin that only leads to a block off plate anyway. The shaft port will be tapped and plugged to better prevent leaks on top of the blockoff plate
Housings and front cover are painted. They came out great and i'm very happy with the finish. I'm going to work on port matching the exhaust port on the stock port housing over the next few days and then get them packed and sent off for resurfacing and just have them sent back to me in texas. But here's how they turned out.
*And yes the paint chips on the edges have already been addressed. It was left over from the masking tape and all I had to do was cut them off with a razor blade in a sawing motion.
Finished painting all of the major engine parts and couldn't resist mocking up the engine to see how it would look together. Can't wait to finally build this engine and be able to pop my hood and see this beautiful killer bee instead of the little stock port green booger engine that's in it now
I also made a jimmy exhaust port matching template to port match the stock rx5 housing. It's not perfect, but i've seen others make a similar template with far worse lines and came out with a great result, so I think it should be fine (will also bevel the edges of the ports for obvious reasons)
So I made it to El Paso and the car did just fine during the 900 mile trip and as stated before I did bring the engine with me. Luckily I have awesome battle buddies that offered to haul my container with the engine parts in it because the weight from it plus all of my other crap was putting quite the load on the rear shocks and i'm not sure they would've held up for 900 miles over 2 days, but i'm here now and have pretty much my whole engine in my closet (the rotor shown in the pic is a non-modified rotor i'm using as a side seal cutting jig for those wondering. I also have an on base auto hobby shop at my disposal that I can use from about 1630-1900 tues-Sat (due to duty hours) where I will be doing all of the work that still needs to be done on the engine (porting, polishing, cleaning, building and of course installing) for about $6/hr. I am still waiting on my custom porting template to get here from Built2Apex (Talked to Nader today, should have that soon) and also my rotors and counter weights to get back from balancing (talked to Carlos about a week ago, not exactly sure how much longer it's going to take, but hopefully not too long. We'll see I guess). I also have a friend back in Utah that does machine work, not sure why I didn't just leave my rear stationary gear with him before I left, but I sent it to him to have an oring groove machined into it as well and sending him the measurements for the front cover oring recess to make an insert so I can use the RX-8 metal gasket for reliable high oil pressure (And yes I will also be ordering an FD regulator as discussed in earlier posts).
If all goes well i'm hoping to have this engine built and installed by the end of next month at the very latest.
04-08-18, 04:51 AM
The lines aren't perfect and there is alot of skipping because the shitty bit I was using weren't very easy to keep in one place, but the skipping marks will be resurfaced out and the imperfect lines should affect much.
