I'm Benjamin Buttoning my RX-7: A build thread.

HunterJP wrote: What is it with you Air Force guys and Rotor motors?

People in the airforce like scary situations and danger

HunterJP wrote: What is it with you Air Force guys and Rotor motors? LOL. My buddy Fitz does the flying thing for the guberment, and has a very nice FD. It is back in Florida now, though, as he picked up a new M3 this last winter.

Pilot type, ehh? Can probably barely spell rotary.

dean1484 wrote: I have always wanted to do a FB but put a miata suspension under it. Then add the motor from a TII. OR (And this is probably just completely crazy) Put the motor form a millenia s in a FB. I did a bunch of research on that motor and it is an engineering marvel. The split block and girdle type main caps were way ahead of its time. If only they put it in a configuration and platform that was more adaptable.

I think all of the Mazda "K" motors were like this. The 2.3 Miller Cycle isn't what you're looking for if that's the one you were talking about.

Watching... I've had several rotaries including an 84 GL that I sold to someone in new zealand. A buddy of mine is also swapping an 13B into an early 1st gen. He's been at it for years though not sure if it'll ever happen :p

Watching. Makes me want to work on my turbo FC, but I've got to get my non-turbo FC sold and my garage cleaned out first. Neither are happening any time soon.

Ironic there was talk earlier about houses eating up your time, oh they do. So for now, just some theory talk.

Fitting the S5 engine into the S3
Physically, this is going to be pretty simple. The S3 transmission bolts right up to the N/A S5, you need the GSL-SE oil pan, and the GSL-SE front cover, because that's where the motor mounts are.

The largest problem is the S5 water pump housing, with it's stupid plastic neck, and lower section that sticks out to leave clearance for the electronic oil metering pump...some grinding will be required to fit with the new front cover. On the other hand, said housing is aluminium, saving about 10lbs off the front of the engine (woo).

Supposedly the thermostat housing is fairly standard bolt spacing and thermostat hole size. Maybe Chevy?

Y U NO use GSL-SE water pump housing? Or S4, with mechanical OMP? Y U NO E36 M3can electronic OMP and save yourself a LOT of trouble?

The S4 or GSL-SE water pump housing will go directly on an S5 motor, no problem. The 2 bolt thermostat housing pattern is real close to a Chevy, but you can't use a Chevy t-stat. The 'stat has to have the blockoff valve on the bottom or the engine will overheat, and I mean quickly.

I left the S5 water pump housing on mine because I had already modified it for clearance for the Jensen crossmember. I used a 12A thermostat housing, added a tab for the 3rd S5 housing bolt and redrilled it so everything would line up. I then brazed a NPT fitting to it for my thermostatic fan switch, I also used a 3/4" thick aluminum block under the t-stat housing so I could use a mechanical water temp gauge, I drilled a hole in the side of the block and tapped it for 1/4 NPT for the bulb adapter.

Curmudgeon wrote: Y U NO use GSL-SE water pump housing? Or S4, with mechanical OMP? Y U NO E36 M3can electronic OMP and save yourself a LOT of trouble? The S4 or GSL-SE water pump housing will go directly on an S5 motor, no problem. The 2 bolt thermostat housing pattern is real close to a Chevy, but you can't use a Chevy t-stat. The 'stat has to have the blockoff valve on the bottom or the engine will overheat, and I mean quickly.

Fear not, there will be NO OMP on the car.

As for why not use the GSL-SE pump, the internet gave me the impression there'd be some drilling and tapping to be had, which I'd rather grind E36 M3 than do. I guess this weekend I'll do the waterpump/front cover swap and find out myself!

Ah, put the mechanical OMP on the car. Then premix your fuel, too!

Buy this . Allows you to get your oil from a source other than the oil pan. Such as a 2 stroke reservoir.

Oh, forgot to mention that on my S4 front cover swap there was a stud boss on the S5 water pump housing that interfered. I had to grind off about 5/16" of it, nowhere near enough to make it too weak.

Not having an OMP of any sort is less expensive, and seeing as I'm trying to challenge budget(ish) this, a practically free blockoff plate is the way to go.

In other news, because I'm eventually going to slap this together as a how-to: if you're doing this, you're going to need a GSL-SE oil pan gasket (if you're going to use one), and the S5 front cover gasket (when I first looked at Mazdatrix's front cover gasket section, my head about exploded). Of course, all the gaskets I've pulled off so far have been a-ok, so I'm going to try and reuse them and of course just use Permatex Right Stuff instead of an oil pan gasket (as is par for the course in a rotary oil pan.

Can you talk to my wife? This is exactly what I want to do, but I will use the Turbo II engine.

1988RedT2 wrote: Can you talk to my wife? This is exactly what I want to do, but I will use the Turbo II engine.

I'm going to need pictures first.

In which I go all OCD on everything

So the auto hobby shop on base doesn't have the funds to fix the sand blaster (thanks, Obama), so it's time to do this E36 M3 by hand.

First, casting marks bug me. Out comes the Dremel. And away goes the ridges.

From there, let's throw a coat of paint on the bitch: I spent a decent amount of time standing in the paint isle, trying to figure out what color of Dupli-Color's Engine Enamel. Eventually, I went with "cast iron," it looks nice, but doesn't stick out, and hopefully engine grime won't show up. We'll see.

Took a quick buffer wheel to the throttle body, shined it up a bit. Also performed half of the throttle body mod, removing and blocking off the cold start assist, but leaving the secondary throttle plates, somewhat because I'm not interested in the side affects associated with removing them, mostly because the damn screws wouldn't come out.

Good choice on the manifold paint, I've used the same color before. It holds up nicely.

Also, in other news, I have gotten a little ahead of myself and purchased a used exhaust already. A tad bit more expensive than the Racing Beat header I was originally looking for, but considering the cost of that header new, and the cost of those Borlas new... Came out under the cost of the Racing Beat and Magnaflow system I was planning, even. "Winning."

Exhaust looks good. Racing Beat Stainless header from the looks of it.

Where did you get it? Custom built or shop built?

Those headers are reaaally long! Hell, that exhaust looks way too long to even FIT under a first gen. That isn't even taking into account that there doesn't appear to be an over axle section-what gives?

Greg Voth wrote: Exhaust looks good. Racing Beat Stainless header from the looks of it. Where did you get it? Custom built or shop built?

It's a Defined Autoworks system. Some guy on the club was having some financial difficulty, judging by the firesale he was having.

MrJoshua wrote: Those headers are reaaally long! Hell, that exhaust looks way too long to even FIT under a first gen. That isn't even taking into account that there doesn't appear to be an over axle section-what gives?

Long primary headers need to clock in at 100+ inches for most good power yes. But you're right about the exhaust not fitting an FB: it's from an FC, I'm going to have to use my "excellent" welding and pipe bending skills to make a few changes.

So you're going to add one 45 degree angle to have a bosozuka pipe out the back, right?

Love this (re)build. I am subscribing.

Osterkraut wrote:

Greg Voth wrote: Exhaust looks good. Racing Beat Stainless header from the looks of it. Where did you get it? Custom built or shop built?

It's a Defined Autoworks system. Some guy on the club was having some financial difficulty, judging by the firesale he was having.

MrJoshua wrote: Those headers are reaaally long! Hell, that exhaust looks way too long to even FIT under a first gen. That isn't even taking into account that there doesn't appear to be an over axle section-what gives?

Long primary headers need to clock in at 100+ inches for most good power yes. But you're right about the exhaust not fitting an FB: it's from an FC, I'm going to have to use my "excellent" welding and pipe bending skills to make a few changes.

IIRC 100" is right in front of the rear axle for a FB. After that you immediately need the over axle 180 degree section. You will likely only be able to fit a rear muffler on that setup and that single straight through Borla is going to be LOUD! Maybe you could shove one of those Auger style muffler cores into the Borla to make the sound wave bounce into the silencing parts a bit more? Another option is to cut into those pretty headers and add the best/biggest presilencer you can find in each leg. That makes a really nice sounding car, but it would be a shame to cut up those headers.

FYI - You can make an exhaust go under a solid rear axle. I've done it many times.