magnumP5's RX-7 Build Thread
- Thread starter magnumP5
- Start date
Okay, here's some in-process shots of the coil bracket. Test fitting the bracket in the car:
A little closer:
It's pretty simple really; just two pieces of 1/8" flat stock formed to shaped and drilled a couple times. As you can see I try to radius all the corners. I think this makes them look a little better. Now with the coils in:
Pretty simple again. Six 1-1/2", four 1" spacers, and some 10-1/2" sections of all-thread and the coils are mounted. The spark plug wires will run together up by the main fuse box and then down to the spark plugs. Once I have everything finished and mounted I'm going to take some measurements and give a call to Magnecor for some custom length 10.5 mm wire.
A little closer:
It's pretty simple really; just two pieces of 1/8" flat stock formed to shaped and drilled a couple times. As you can see I try to radius all the corners. I think this makes them look a little better. Now with the coils in:
Pretty simple again. Six 1-1/2", four 1" spacers, and some 10-1/2" sections of all-thread and the coils are mounted. The spark plug wires will run together up by the main fuse box and then down to the spark plugs. Once I have everything finished and mounted I'm going to take some measurements and give a call to Magnecor for some custom length 10.5 mm wire.
mymmeryloss
Member
- :
- 13bT Mazda B2600i
Looks good! I will probably copy your bracket design somewhat if u dont mind...
You wouldn't be copying me. You'd be copying the person who copied the person who copied the person... who I copied, LOL! I thought about making the bracket a little fancier but this will work for the time being. In the distant future I may come back and replace all these brackets I've made with professionally machined ones. For now if it does its job, is durable, and isn't ass-ugly it'll do.
I finished painting the bracket so I mounted and started wiring the coils (switched 12V and trigger done so far):
The wiring's a little trickier than the others because the terminals are pull-to-seat. I've decided to arrange the coils as L2, T2, L1, T1 from left to right. This should result in the shortest possible leads. Ignore the wire tied to the T1 post; I was using it to determine the lengths needed for the leads. Once the coils are done the only wiring that remains is the IAT, starter and alternator, and then I can wrap everything up (yay!).
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- aggressive auto culture
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mymmeryloss
Member
- :
- 13bT Mazda B2600i
Looks great!
Thanks; it's getting there!
I'm working on grounding the coils; each coil has three grounds and there are four coils so it's a lot of wire! Based on input from Ludwig Motorsports I'm ganging them all together and grounding to the engine despite what the AEM instructions say to do. That same discussion also has me redoing my engine ground. I currently have a 12" piece of 2 AWG going from the battery (-) to the chassis and then a 4 AWG wire from the chassis to the engine. I'm changing it to a long stretch of 2 AWG from the battery (-) to the engine and then a very short 4 AWG wire from the engine to the firewall (chassis). This should ensure the best possible engine ground and I won't need to separately ground the starter and alternator bodies. I may still ground the battery (-) directly to the chassis so the fuel pump and electric fan have the best possible grounds as well.
I've got my in-laws visiting 7/5-7/9 so that means cleaning tonight and tomorrow, which means very little, if any, work being done on the RX-7 for the next week.
Despite heat indices over 110 degrees I've made some small progress. The loom
for the coils is done. I just need to connect all the wires to the main engine
harness.
My custom K&N filters also came in so I tapped one for the IAT sensor and
mocked them up.
I put the IAT sensor in the rear filter because I figure that'll have hotter
intake temperatures and therefore be the limiting factor. I really need to find
a way to get cooler air to the filters. A TII hood should put air in the general
area...
for the coils is done. I just need to connect all the wires to the main engine
harness.
My custom K&N filters also came in so I tapped one for the IAT sensor and
mocked them up.
I put the IAT sensor in the rear filter because I figure that'll have hotter
intake temperatures and therefore be the limiting factor. I really need to find
a way to get cooler air to the filters. A TII hood should put air in the general
area...
mymmeryloss
Member
- :
- 13bT Mazda B2600i
For some reason i think my coils are smaller than that but i could be wrong...
Maybe they revised them? If they did I'll be slightly irked because getting these to fit somewhere was difficult.
See above. This was really the only open location left. They're actually tucked quite nicely behind the headlight.
PrinceValorum
Member
- :
- 95 626 FS, 89 Toyota Derux 4x4
Cool air you say? Mad Mike had you covered again!
mymmeryloss
Member
- :
- 13bT Mazda B2600i
Braaap braaap braaaaaaaaaaap...
Love that car!
Love that car!
I'm not dead. Between taking a week off for the Fourth of July and this rediculous heat I've lost the drive to work on the car for a bit. The exhaust manifold is still WIP, but perhaps once that comes in or least when the heat dies down, I'll really start working again. Everything left is pretty straightforward. The only BIG unknown at this point is the fan/radiator ducting.
If that was directed at me, no, I'm not on RX7Club. I do sometimes use it as a reference but I really don't like how things are run over there. There's blatant favoritism toward a select few members/vendors, who, from what I've read elsewhere online, have a less the stellar reputation. Too many teenagers with FC's and Initial D aspirations for me as well. I'm on Rotary Car Club, which is partially run by Phil (Herblenny). It's a much smaller, more technical forum.
Still no progress on the car. I've spent the last few weekends getting the house ready for the baby in October. I'm seriously considering buying something I don't necessarily need right now (e.g. passenger's seat) just because getting parts in the mail seems to make me want to work. I've been thinking about the radiator/oil cooler ducting and I'm thinking I may relocate the oil cooler slightly for more of a v-mount setup with the radiator. Right now they're in series, which means cool air either bypasses the oil cooler to get to the radiator or it goes through the oil cooler and heats up before reaching the radiator. Either scenario is not ideal.
Quick update. Gave Logan at Defined Autoworks a call to check on the status of the exhaust manifold. Everything's just about ready; just waiting on a SS flange from Racing Beat (they were backordered). *Excited*
I'll also pose another discussion topic: RX-8 rotating assembly. I have the rotating assembly from my previous engine: eccentric shaft, rotors (9.7:1 compression), and stationary gears. An option I have is to replace the eccentric shaft and/or stationary gears from an RX-8. The benefits are the RX-8 eccentric shaft is ~0.5 lbs lighter and the stationary gears are supposedly hardened, three-window types and they are a matched set (eccentric shaft clearance). The only downsides involve a nonexistent o-ring seal groove on the rear stationary gear (must use sealant or machine a groove in the RX-8 gear) and an oil galley in the rear iron (must modify rear iron). The other aspect is cost as I already have a perfectly fine eccentric shaft and stationary gears. The RX-8 stuff would be about ~$500 total. Technically I wouldn't have to balance the rotating assembly since the eccentic shaft is balanced to itself, I'd be using matching front/rear counterweights to my rotors and I'm planning on keeping the redline at 9000 RPM (max on tachometer). However, if I got the RX-8 stuff I'm considering balancing the assembly anyway in case I want/need to wind the engine to 10,000+ RPM. Balancing is about another $300. So, is ~$800 extra worth -0.5 lbs in weight, stronger and better lubricating stationary gears and a perfectly balanced rotating assembly?
I'll also pose another discussion topic: RX-8 rotating assembly. I have the rotating assembly from my previous engine: eccentric shaft, rotors (9.7:1 compression), and stationary gears. An option I have is to replace the eccentric shaft and/or stationary gears from an RX-8. The benefits are the RX-8 eccentric shaft is ~0.5 lbs lighter and the stationary gears are supposedly hardened, three-window types and they are a matched set (eccentric shaft clearance). The only downsides involve a nonexistent o-ring seal groove on the rear stationary gear (must use sealant or machine a groove in the RX-8 gear) and an oil galley in the rear iron (must modify rear iron). The other aspect is cost as I already have a perfectly fine eccentric shaft and stationary gears. The RX-8 stuff would be about ~$500 total. Technically I wouldn't have to balance the rotating assembly since the eccentic shaft is balanced to itself, I'd be using matching front/rear counterweights to my rotors and I'm planning on keeping the redline at 9000 RPM (max on tachometer). However, if I got the RX-8 stuff I'm considering balancing the assembly anyway in case I want/need to wind the engine to 10,000+ RPM. Balancing is about another $300. So, is ~$800 extra worth -0.5 lbs in weight, stronger and better lubricating stationary gears and a perfectly balanced rotating assembly?
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I called Mazdatrix and apparently I'd need to balance the engine anyway if using the RX-8 eccentric shaft so that answers that question. Since I'm having them do the balancing I'm just going to order the parts I need from them as well to save some on shipping. Unfortunately I won't be able to get to this until next week as I'll be out of town this weekend. It's too bad running RX-8 rotors requires so much work because they're 10:1 compression...
