I took care of a few odds and ends by double checking the fuel pump and wastegates’ springs. Kind of boring, but this had to be done because these components are so crucial.
When I bought the car, one of the items on its rather minimal mod-list was a Denso Supra Twin Turbo fuel pump. These flow well past 400whp and significantly more than the factory RX-7 unit, which is insufficient for much more than stock power. There was no way I could overlook this, so I popped off the fuel pump cover and stuck my cellphone in to snap a few pictures.
I was able to grab the part number off the pump, and sure enough – Supra fuel pump confirmed.
Next, I double checked the springs on my Tial wastegates (more on these in a later post). I specifically requested to have 12 psi springs pre-installed and I will not be using a boost controller.
Blue and Black springs were in both wastegates, these are Tial’s current colors to denote a 12 psi combo. Check.
At one point, I was able to reinstall the upper intake manifold and hook up the fuel pressure regulator.
The fuel pressure gauge isn’t installed here, because I had to reorder one. I spent an hour looking all over my garage for the gauge… only to find it chewed up in my dog’s crate the next morning. He usually doesn’t touch anything in the garage, but the small size of the gauge must have made it look like a ball. Oh well.
And here’s the Greddy compression elbow, a staple of any RX-7′s engine bay.
Unfortunately, I wasn’t entirely happy with a couple of the fuel lines. One line had a bend I didn’t like to it, and the other was too long. So off came the UIM again. I’m still working on this part… to be continued.
It took me less than a month to grow tired of the Work XD9‘s that were on the car. They were simply too generic and lacked a certain element I was looking for. Picking the right wheels is extremely important, they can single-handedly transform your car. This is probably why it’s common to see people go through multiple sets of wheels – and it’s definitely not an area you want to skimp out on.
Aside from feeling that the XD9′s were bland, there was something off about their sizing to me. Maybe it was just the design of the face on those wheels, but in 18″, they seemed too big on the car. I’m taking the opportunity to step down to 17″ wheels. I think the larger sidewalls will balance out the proportions on this car when fit right, we’ll see how it goes.
I also wanted to find wheels that were more worthy, so I reverted to my short-list of favorites and picked the choice at the top: RegaMasters. I love the simplicity in their design, it’s almost utilitarian like. They are also more period correct to the RX-7 and have long been discontinued – which increases their rarity. This is a plus although adds to the challenge of sourcing them, as you’ll read…
I had to turn to looking overseas to find what I needed. I initially bought a set of 17×9′s from a seller in Japan. I really wanted 17×10′s but it was almost impossible to find a +40 offset for the fronts, so I settled on the 17×9′s instead. I had expressed this intention to the seller, and this lead to a tip from him a month and a half later. Apparently, as luck would have it, a 17×10 +40 pair popped up on a Yahoo Japan auction.
Since this seller wasn’t the cheapest (it would have cost me around $2500-2700 to go through him), I decided to take his information and go behind his back to save a few bucks. I had to work fast because the auction was ending soon. I did my research and quickly contacted Jesse Streeter, who specializes in proxy services. We moved fast, a bet was placed on the 17×10 +40 pair and another 17×10 +20 pair (for the rears). The next thing I know, my 17×10 RegaMasters were at my doorstep a week and half later.
I decided to spring for EMS shipping. The funny thing is, my first 17×9 set was shipped through a container, and didn’t arrive until almost a month later.
Forged in Russia, with love.
Note: Desmond made 2 types of RegaMasters, the Evo and the Marquis Promada. The former is slightly more rare but is not offered in many of the larger sizings. To tell the difference between Evos and Marquis Promadas (MP), look at the hub. MP’s will have a raised hub area for the center caps. Additionally, they also have a recessed groove that circumvent the inside edge of the spokes.
A few of the wheels had minor curb rashes, but curb rashes nonetheless. This meant that I couldn’t simply drop them off to the powder coaters to be repainted… they needed to be refinished first. I decided to keep to the color of the silver pair for the set (equivalent of Prismatic Powder’s Porsche Silver). This should help “tame” the car’s appearance, although I will miss the black on black look.
I chose Wheel Techniques in Santa Clara to do the refinishing, because they weld on new material to the curb rashes rather than simply fill them like some other shops do. Unfortunately, the refinishing process took far longer than anticipated. One of the wheels came out with a bad clear coat and needed to be redone, and I noticed minor inconsistencies on a couple of the other wheels. One thing led to another, it took over 4 weeks to finally get all of the wheels down to a satisfactory result.
I wasn’t in any rush so it worked out to that end. I’m appreciative that Wheel Techniques was willing to work with me and see it through by continuing to redo their work. They’re a busy shop, and Jeff, the co-owner, even personally extended an offer to redo a wheel, when I was about to just accept it and go… so I thought that was a classy act and gets major kudos in my book.
Let’s cut to the chase here…
Here’s a picture of both sets of my RegaMasters, with the 17×9′s in the foreground. You can see the small difference in the step lip depth between the 10″ and 9″. This difference was reason enough to make me buy 2 sets of these wheels.
Mounted on Hankook RS-3′s.
Whether I go with 17″ or 18″ wheels, one thing I will always keep is the fitment. I will continue to stay with a squared set up and with 10″ wide wheels all around with 255 width tires. I think 255′s on a 10″ is perfect. The pinch and stretch are just right. If the tires did not have a rim protector, the cross-sectional widths would basically be squared on the 10″ wheel.
Slowly but surely, I’m ticking off the items from a very long to-do list. I’m doing my best to approach this build as methodically as possible, I don’t want to rush. In abide by this ideal and still see a conclusion within a reasonable timeframe, I have to do or plan something daily.
Today, I pushed forward with the reassembly and took care of various tasks. I started by installing the HKS Twin Power unit.
Because I removed my A/C and Power Steering, a very prime location became available on the frame rail for mounting:
That spot was perfect, the piggy back harness was within good reach of the plugs and the box is relatively far from the engine’s heat. Furthermore, being down low and in an open area allows for increased air flow.
I also connected the Magnacore spark plug wires and buttoned up the coils. In my haste to get rid of the sequential system rat’s nest, I overlooked an important bracket necessary to mount the coil assembly (sold it away). Everything under there is intertwined with each other, and this bracket was actually an offshoot of the rat’s nest assembly.
This lead to a dilemma as I wasn’t sure how to find such a specific part. I called Mazda and they no longer carried it. I decided to try a Want to Buy ad on RX7Club’s classifieds. It was more or less a shot in the dark, but within a couple hours of posting, Ihor from IRPerformance came to the rescue. It’s a blessing that this car still maintains a strong resource-sharing community.
The clear braided hose in the picture below is a PVC Tygon line I’m using to vent/catch blow-by. I deleted the Positive Crankcase Ventilation (PCV) in the process. I may add in a catch-can in the future if the hose is not adequate and I notice excess oil in the intake tracts, but it shouldn’t be an issue in less than racing conditions.
I like to do my own work for a reason. It allows me to dictate full control of the operation and impart a more crucial eye. I feel that certain levels of attention to detail cannot be captured when you drop your car off to someone else – only unless you’re prepared to sign a big check.
For example, one of the benefits I’m able to enjoy is being able to handpick everything to my liking, down to even the replacement vacuum hoses. Even though there are barely any vacuum hoses left, it’s still an area that deserves scrutiny. Here’s a picture of a 3.5mm silicone vacuum hose I’m intending to use for the Blow-off Valve – the walls are nice and thick.
On the subject of vacuum hoses, I’m amazed at just how simplified the vacuum system is now. These are all that’s left:
- Wastegate Boost Pressure Sources (x2)
- Fuel Pressure Regulator
- Blow-off Valve
- Injector Atomization
- MAP sensor
- Check Valve (only Solenoid retained) -> Charcoal Canister
Initially, I was only going to upgrade the secondary injectors and retain the stock primaries. Planning out the fuel system required a good deal of thought and effort, and I eventually succumbed to upgrading the primaries as well. Namely, it didn’t feel right mixing new and 2-decade old technologies together.
I went with Full Function Engineering CNC’d and anodized rails with flow-matched Injector Dynamics 2000′s for the secondaries and Injector Dynamics 725′s for the primaries. This set up should be able to support past 500HP, although I won’t be pushing anywhere close to that. I was eventually able to amass this collection of goodies:
I bought more push lock fittings than necessary to have spares, and it’s a good thing I did, because 3 of them were sacrificed in the process of the install. I first measured out and cut the lengths out of a Fragola 8000 hose, but when I tried to push on the fittings, it just wasn’t happening. The tolerances between the Fragola hose and the Red Horse Performance fittings I had were slightly off, and that was enough to make it impossible. So I switched over to an Earl’s Super Stock fuel hose, and that was a good match – but still by no means easy.
I wasted enough effort with the first setup and it was getting late by the time I finally got one fitting installed. So the next morning, I decided to enlist the help of someone I thought would be better suited for the job. I wanted to hedge against uncertainty and make sure all the fittings would be pushed on all the way, there were no more second tries – supplies were dwindling. By the design of the push lock barbs, if you stop pushing while half-way on, it becomes very difficult to fully seat the hose.
To help further guarantee a successful outcome, I took all possible preparations: the fittings were left in the freezer to contract the metal, the barbs were lubricated with oil, and the hose was boiled in water to expand the rubber. Mr. Freshlove (check out his blog) made the job look like easy money.
Fuel lines complete. I used Oetiker stainless clamps over the barbs as added security.
Here’s a look at the fuel rails installed on the car. Impeccable machine work, everything fit together flawlessly.
And with the lines plumbed.
I’m maintaining the stock Series routing, but I chose to feed the secondary rail first to help with the transition to the big 2000cc injectors. The factory setup feeds the primary first and then the secondary. I didn’t feel that it was necessary to add in clutter and run a Parallel setup (where both the secondary and primary rails are fed simultaneously via a Y-block).
I’ll need to finish it off by hooking up the Fuel Pressure Regulator, but I will get to that when the UIM goes back on.
I just finished Winter session at school. Condensing a normal 4-month quarter into 2 and a half weeks meant long hours in class… especially so because I petitioned to take an extra, second class.
Well, with that over now, I had a whole 3 days off before work and Spring quarter starts again. To catch up, I did plug away at a few things whenever I had a spare minute or two.
I finished up the Apex’i PowerFC inside the cabin.
I have the Commander unit mounted to a windshield holder, because that was all I could figure out. A “perfect” mounting solution does not exist, the other alternatives are equally as bad or worse, so this will do for now.
With the A/C’s evaporator removed from under the dash, the non-A/C duct arrived from Mazda to fill the gap. Installing the duct was painful, I was nearly in tears by the end of it. The duct was fairly rigid and the openings needed to be pushed on precisely. It didn’t help that its placement was in the upper cavities of the dash. I’m glad that’s over with. The end result does at least free up space significantly.
Moving back to the engine bay, I cleaned up the LIM, stuck on some heat tape for good measure, and reinstalled it with a fresh OEM gasket. This should have been as easy as it sounds, if it weren’t for the old paper gasket that was glued to the irons. It appears that Mazda used this green, paper-type gasket early on. The new gasket I bought from Ray @ Malloy Mazda is black and made from better materials.
I was forced to slowly razor blade off the old gasket. I spread this task over a few days. It was scrape, soak with Permatex Gasket-Remover, scrape some more, and repeat. At the end, I was able to clean everything off with a brass wire wheel.
I also applied gold heat tape to the chassis. I might add more later, but I’m running low on the tape – and that stuff is NOT cheap.
I initially was not planning on blocking off the oil metering pump, but after further thought, I proceeded in doing so. A fair amount of debating was required to surmise the benefits of the OMP’s removal. I approached the decision process logically, I wasn’t trying to continue my spree of simplification in the name of reduced weight, or anything vain like that (although on that note, the OMP is actually a couple of pounds, and heavier than the other small components I’ve removed).
Since I’m moving to the PowerFC standalone, the ECU will not care either way if the OMP is plugged in or not. On the flipside, this means that should the pump ever fail, I won’t know about it because an error code will not be thrown. I felt that this was rather risky given the importance of lubrication in a rotary engine.
Furthermore, and more fundamentally, Mazda included the function of the OMP as a band-aid, so-to-speak. The purpose of the pump, as its name suggests, is to meter in a small amount of oil near where the primary fuel injectors are. This is not a preferred solution, because the OMP’s injectors are only able to lubricate one portion of the rotor. The second fault is that the OMP has to draw its source directly from the oil pan. Engine oil is not meant for this kind of lubrication, it does not burn clean and leaves deposits.
The best method is to premix, into the gas tank, with TCW-3 rated 2-stroke oil. This provides complete coverage and utilizes oil meant for the task. Of course, there’s no way Mazda’s corporate could sell the idea of asking owners to calculate and measure how much oil is needed for premixing during fill-ups – hence the implementation of the OMP.
I don’t mind the extra step of premixing without the OMP. Plus, it’s recommended to premix anyway, even with the OMP, albeit with a smaller ratio.
With that said, here is the OMP blocked off and its 2 injector ports plugged.
The actual OMP, note the plastic lines…
I also decided to muster up the courage to remove the fuel injector’s o-rings and diffusers. I had premonitions about this part, because the plastic diffusers are brittle and located in a very precarious location. I was able to remove the secondary injector’s o-rings and diffusers without much trouble. Then I moved to the primary injectors on the engine. I had to make a hook to use here. A small tug and the top portion of the diffusers came out, but ONLY the top portion. The bottom halves snapped cleanly off. Lo and behold, the outcome I was dreading and took extra precautions against still happened.
This was without a doubt a major ass-puckering moment. I quickly decided to take off the lower intake manifold, and was luckily able to get them out easily through the side port. Thank God. I thought they were stuck in the depths of the engine for good, this would have been game over.
Here you can see what I’m talking about…
LIM removed, I’m going to take this opportunity to order a new gasket and hardware for reinstall.
Why Mazda used PLASTIC for something hanging in the middle of the engine, in such a crucial location, I will never understand. I’ve read about people taking out their diffusers only to find portions of them deteriorated and missing. This means their engines ATE those pieces. And of course, engines have been lost this way as well.
I will NOT be putting these plastic ticking time bombs back in. I’m going with new injectors anyway, which are new technology and have better atomization, so the diffusers are not necessary.
I think this was from one of my late-night wrenching sessions during the previous week.
Blue is an excellent garage dog, he doesn’t mess with my bolts and tools. He’s very passive and just observes, great company. Once in the while, if I’m on the floor under the car, he will climb in to see what’s going on.
This is impressively crazy and stupid. Judging by the Portuguese, I’m willing to wager the location is Brazil? What better way to wake up than to lane split at triple digit speeds on your way to work. Quite the gauntlet, would’ve been better if he wheelied the whole thing.
With the upper intake manifold free, I took the opportunity to strip it back down to bare aluminum. It was previously painted black, which I didn’t particularly favor. It seemed to have cheapened the look of the engine. I’m not going for a show-quality engine bay, I am strictly chasing function. I’m not going to bother with polishing or adding bling. I just want to maintain a stock-ish, silver colored look.
I used Aircraft Paint Stripper to take off the paint, but it worked wonderfully. It took about 3 applications to finish. The black paint may have even been powder coat, so I’m surprised at how efficient the paint stripper chemicals are – the paint could literally be wiped off after.
Next, it was time to tackle the block-off plates. This part really highlights the degree of simplification that can be done to the engine. On the UIM, I blocked off the Double Throttle, Accelerated Warm-Up System, and the Accelerated Warm-Up System Tube.
On the Lower Intake Manifold, the Air Control Valve…
…Air Control Valve Tube, Split Air Pipe, and Exhaust Gas Recirculation were blocked off – as well as the Rear Turbo Oil Line at the bottom of the block.
These components were originally attached via studs, which all had to be unthreaded via the double-nut method to be replaced with screws. The gasket for the Split Air Pipe was strangely bonded to the LIM, and had to be painstakingly scraped off given its awkward location. Eventually, several passes with a Dremel got it all cleaned up. To seal the block off plates, I used Permatex’s “the Right Stuff”, which is superior to the regular RTV gasket-makers you normally buy at auto supply stores.
After obviating so much, the amount of simplicity achieved offers a more refined platform, in my opinion. All the emissions, sequential, and driver-aid related shenanigans Mazda crammed in were nothing more than increased fail-points and unnecessary complexity.
With the block off plates done, I decided to throw on the new spark plugs. I will be using NGK BUR9EQP’s all around, in both the trailing and leading positions. I am also going to replace the spark plug wires with Magnacore 10mm race wires. In the picture below, you can see the girth difference between the Magnacores (bottom) and stock (top).
Finally, I removed both the primary and secondary fuel rails plus injectors. Now I can start planning my new fuel system and what fittings I’ll need to plumb it.
To round out the end of the year, I definitely put in work. In order to get to where I am now with the project, I dedicated a few hours every single day during the past week and a half. My garage is littered with boxes full of parts I’ve removed from the car. I am basically done with taking stuff off, I can now start on putting everything back together, anew.
I may not be able to continue chugging along at the current pace, because my Winter break is over and the hectic of normal life is about to resume. Nonetheless, I will plug away at the car whenever granted with the chance. 2013 is shaping up to be an exciting year!
This is what I’ve been up to during the past few days.
I finally installed the manual steering rack. Getting the old power steering rack out was interesting. The space down there was really tight, I had to figure out the one specific combination of movements to get it out. The driver-side of the front subframe needed to be lowered in order to gain more clearance. It was either that or remove 2 oil cooler lines.
With the old rack removed, I then needed to index the new one to exactly center. I tried manually measuring center to no avail, so I simply approximated it on the manual rack and installed it. Once on the car, I shifted off the intermediate joint accordingly. For example, if I noted that I was getting too many turns to the left side, I would move the splines over until it was centered.
I was delayed from finishing the install because I slightly stripped one of the threads on the passenger-side steering rack clamp. I replaced the rack bushings with new poly SuperPro ones, which made lining up the holes harder. No worries… I rang up Ray Crowe at Malloy Mazda the next day, and a few minutes later, an order was placed to over-night a new clamp.
I also lied about being done with chassis braces… I forgot I actually had one more: the Racing Beat sway bar brace. This one looks to be a useful one, because the stock sway bar mounts are not triangulated or reinforced, so they crack under hard cornering. The Racing Beat brace ties in the mounts with the subframe, via the steering rack’s forward holes.
Next I installed the Apex’i PowerFC standalone ECU. I previously bought a used one, and then resold it because I decided I wanted it new to get the revised Commander unit. The newer models come with an OLED display. An expensive disposition to have, but this computer is expensive to begin with… so what’s a few hundred more.
To delete the coolant system’s air separation tank, I bought a kit from Ray @ Malloy. It is basically just a 1986 RX-7′s coolant fill neck and pressure cap, which function in the same way as the AST does to relieve air from the system. The nipple on the housing originally went to the AST, so I plugged it with a short hose and a cut-down stainless steel bolt and stainless steel worm-gear clamps. I’ve been going out of my way to obtain stainless hardware wherever applicable.
As seen in the picture above, I also threw on the Greddy alternator and water pump pulleys (necessary in order to remove the air pump). It’s nice to know that these 2 pulleys are going to be the only ones left in the car.
Moving on, it was time to yank the upper intake manifold and unleash the “Rat’s Nest”. You can see why people call the solenoid rack that name. The previous owner at one point refreshed all the vacuum lines with silicone variants.
With the manifold off, I took the opportunity to remove its double throttle and associated actuator. The double throttle serves to prevent the driver from using too much throttle until the car is fully warmed up. Not really a useful feature for anyone who isn’t a total idiot.
I was able to remove one of the screws holding on the butterflies of the double throttle with an impact driver, but the remaining 3 had to be drilled out.
I later went back to the engine bay and tore out the rat’s nest.
I’m undertaking various simplification jobs, but the solenoid rack is probably the principal one. All the crazy sequential-related wastegate solenoids and emission solenoids are gone. The car is going to have one solenoid remaining by the end of this – the charcoal canister’s purge control.
Since I’ve been predominantly focusing on ripping things out of the car, it’s probably counter-intuitive to think that I am actually making good progress – but I think I am.
Today, I moved into the interior and finally got a chance to de-rice the car by taking out the dual A-pillar gauges. I was fixed on removing these from day one. When buying the car, I requested that the 2 other gauges mounted to the center speaker location on the dash be omitted from the sale. In the end, only the gauges were removed but not the lines going to them under the dash, so I took care of that as well.
Judging by how many lines there were, it’s fair to say I’ve undone what was a rather intensive installation.
Replaced this ugly thing with a new, gauge-less OEM A-pillar.
I like my interior to be clutter-less. I can get all the information I’ll need from the Apex’i PowerFC’s Commander (which I plan to install tomorrow).
I also finished off the removal of the Air Conditioning system by taking out the large evaporator sitting behind the glovebox, in the passenger-side footwell.
Removing the evaporator frees up a lot of space, but leaves a large empty gap. The evaporator additionally served to connect together the heater core. One option gut out the shell of the evaporator and then install it back in, so the heater can still function. Or, there is a specific duct available to go in place of the evaporator on non-A/C equipped RX-7′s, which I am going to try and procure (Mazda part number FD01-61-150b). This should provide a more elegant solution. If it’s unavailable, I will revert to the former option.
All together, I’d wager the entire A/C system weighing around 35-40lbs. The bulk of its weight is from the compressor, everything is else relatively light. Regardless, not having the lines spread all over the engine bay is worth it alone.