Rotary Stuff
07-16-14, 01:02 AM
#1
Rotary Stuff
Today I lengthened an OMP rod from an FB to work on an S4 NA that has a modded manifold to fit a Nikki. Would I use any other carb? 
Also I figured out some OMP tubes on the RE-SI front cover (it's the same as GSL-SE with a 4 outlet OMP). They'll go to the rotor housing oil holes and the Nikki nipples. Best of both worlds?
Got the engine stacked last week. It has 74 ported primaries and stock but smoothed secondaries and aux ports. Hey, these 6 ports already have too much port timing from the factory as it is - kind of a risk to port the primaries but you do 90% of your driving on them and it's getting a hogged Nikki to deal with the higher flow. Exhaust diffusers were cut and ground away to a more T2 type sleeve and normal tension bolts were swapped in. I even like the color.
Yes, it's a white engine. Some said it shouldn't be done. That it would get dirty before it's even installed. Um, I just won't touch it.
And here is a closeup of the OMP rod that needed lengthening because a) the 13B is longer than a 12A and b) the manifold sticks out from the engine due to the 13B flange welded to the 12A manifold. It needed 10mm of length added. Then painted with epoxy paint for rust resistance and scratch resistance. Oh don't mind the ugly manifold and waterpump. They're just there for test fitting.
In case you're wondering, I've thought about doing a white and silver engine for a long time now, but let thoughts of it getting dirty too easily control my decisions. Well, not anymore. Kinda like this thread. I've been thinking about doing a thread like this for months to sort of chronicle what I do around here so I can go back and research if necessary.
What I won't post is speculation and "oh I'd like to do this and this and this" because you and I know it'll never get done. This is more of an evening update type thread.
Also I figured out some OMP tubes on the RE-SI front cover (it's the same as GSL-SE with a 4 outlet OMP). They'll go to the rotor housing oil holes and the Nikki nipples. Best of both worlds?
Got the engine stacked last week. It has 74 ported primaries and stock but smoothed secondaries and aux ports. Hey, these 6 ports already have too much port timing from the factory as it is - kind of a risk to port the primaries but you do 90% of your driving on them and it's getting a hogged Nikki to deal with the higher flow. Exhaust diffusers were cut and ground away to a more T2 type sleeve and normal tension bolts were swapped in. I even like the color.
Yes, it's a white engine. Some said it shouldn't be done. That it would get dirty before it's even installed. Um, I just won't touch it.
And here is a closeup of the OMP rod that needed lengthening because a) the 13B is longer than a 12A and b) the manifold sticks out from the engine due to the 13B flange welded to the 12A manifold. It needed 10mm of length added. Then painted with epoxy paint for rust resistance and scratch resistance. Oh don't mind the ugly manifold and waterpump. They're just there for test fitting.
In case you're wondering, I've thought about doing a white and silver engine for a long time now, but let thoughts of it getting dirty too easily control my decisions. Well, not anymore. Kinda like this thread. I've been thinking about doing a thread like this for months to sort of chronicle what I do around here so I can go back and research if necessary.
What I won't post is speculation and "oh I'd like to do this and this and this" because you and I know it'll never get done. This is more of an evening update type thread.
Last edited by mazdaverx713b; 07-17-14 at 01:35 PM.
07-16-14, 02:23 AM
#3
I did them the same as the SE.
Normal thickness tension bolts are what I swapped in. The S4 NA comes stock with strange thin machined stretchy tension bolts. I think it was Mazda's way of shaving a little weight off the engine, but I don't trust them for boost so they had to go.
Notice I also drilled and tapped the front cover for an oil return fitting, currently blocked with a blue anodized NPT plug. I could have used the undrilled boss under the OMP but that's too much work to deal with. You'll see why if I decide to post some older pics of a boost prepped Nikki setup using this front cover as a place holder...
Normal thickness tension bolts are what I swapped in. The S4 NA comes stock with strange thin machined stretchy tension bolts. I think it was Mazda's way of shaving a little weight off the engine, but I don't trust them for boost so they had to go.
Notice I also drilled and tapped the front cover for an oil return fitting, currently blocked with a blue anodized NPT plug. I could have used the undrilled boss under the OMP but that's too much work to deal with. You'll see why if I decide to post some older pics of a boost prepped Nikki setup using this front cover as a place holder...
07-16-14, 02:30 AM
#4
Ok, I didn't work on this today, but it will shed some light on what I was talking about regarding the oil return fitting in the front cover.
Here is the RE-SI front cover with a 5/8" brass fitting aimed right at the turbo oil return line. It just needed a short length of oil resistant hose.
Here is the RE-SI front cover with a 5/8" brass fitting aimed right at the turbo oil return line. It just needed a short length of oil resistant hose.
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07-17-14, 01:24 AM
#8
I found the brass fitting and a length of oil resistant hose on ebay. It was pretty easy to work with. It doesn't need to handle high pressures, just oil. Mine was rated up to 300psi if you were wondering.
And an update. The white and silver shortblock is in!
And an update. The white and silver shortblock is in!
07-17-14, 10:46 AM
#13
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i think the CAS is bad in my FC-REW, so i went to the Mancave and found the spares, which say bad on them in sharpie, typical!
today Fungus mungus is coming by, so i need to go make sure peepers runs...
today Fungus mungus is coming by, so i need to go make sure peepers runs...
07-17-14, 02:43 PM
#15
Ah, the thread title has been corrected.
The clutch master was out of fluid so I poured some in. It wouldn't push the slave so time to bleed! Um it didn't want to bleed. The bleeder screw was clogged. Removed it, used a tiny drill bit to break up the crud. Rinse, blow out with compressed air. Now it bleeds! Now there's fresh fluid in the master and slave.
The clutch pedal feels perfect but might need some minor adjustments when up and running.
The clutch master was out of fluid so I poured some in. It wouldn't push the slave so time to bleed! Um it didn't want to bleed. The bleeder screw was clogged. Removed it, used a tiny drill bit to break up the crud. Rinse, blow out with compressed air. Now it bleeds! Now there's fresh fluid in the master and slave.
The clutch pedal feels perfect but might need some minor adjustments when up and running.
07-17-14, 03:15 PM
#16
Ok, I didn't work on this today, but it will shed some light on what I was talking about regarding the oil return fitting in the front cover.
Here is the RE-SI front cover with a 5/8" brass fitting aimed right at the turbo oil return line. It just needed a short length of oil resistant hose.
Here is the RE-SI front cover with a 5/8" brass fitting aimed right at the turbo oil return line. It just needed a short length of oil resistant hose.
Wait I don't want to know. Because either you didn't spend that much and got lucky/ made it yourself. OR it cost more than 3 weeks of my pay and I don't need such temptations.
AWSOME engine BTW and it has the proper way for a rotary to get feed fuel.
07-18-14, 12:33 AM
#17
It won't fit your 12A. Let's just leave it at that.
Success! The white and silver engine runs! It fired up quickly after a 4 or 5 seconds of cranking. Ran fine even though the Nikki had a stuck accel pump. I didn't let that stop me, and the engine didn't mind at all.
What I did was take the top of the carb off, fill each bowl manually with gas and put the top back on. Reason is the gas in the tank is old and nasty so I won't use that.
I let it run for 30-40 seconds on what was in the bowls then let it stall out on its own (no choke cable). Then the all-important second attempt at starting which is the critical one where any assembly lube has already burned off. Will it restart? Of course it did.
It ran for like 10 seonds and was then empty.
So I removed the carb and figured out what wasn't allowing the accel pump to squirt. The small steel ball under the accel nozzle was stuck for some reason. Got it freed up and filled the carb with more gas, then ran out of dayhlight so I'll... oops that's mentioning what I'll do tomorrow. Gotta keep in mind this is an update thread. You'll have to stay tuned.
Success! The white and silver engine runs! It fired up quickly after a 4 or 5 seconds of cranking. Ran fine even though the Nikki had a stuck accel pump. I didn't let that stop me, and the engine didn't mind at all.
What I did was take the top of the carb off, fill each bowl manually with gas and put the top back on. Reason is the gas in the tank is old and nasty so I won't use that.
I let it run for 30-40 seconds on what was in the bowls then let it stall out on its own (no choke cable). Then the all-important second attempt at starting which is the critical one where any assembly lube has already burned off. Will it restart? Of course it did.
It ran for like 10 seonds and was then empty.So I removed the carb and figured out what wasn't allowing the accel pump to squirt. The small steel ball under the accel nozzle was stuck for some reason. Got it freed up and filled the carb with more gas, then ran out of dayhlight so I'll... oops that's mentioning what I'll do tomorrow. Gotta keep in mind this is an update thread. You'll have to stay tuned.
07-19-14, 12:24 AM
#18
Coolant was added and the engine was cranked. It was kinda flooded due to the carb having been over-filled yesterday. 
Even so, it started really easily and wanted to idle on its own a bit sooner than I was expecting. Turns out the idle is adjusted slightly rich on this carb. No problem.
Then I realized the RE-SI OMP wasn't connected to the Nikki. No problem as no oil had made its way out yet. So I grabbed a couple of ends and pieces of vacuum hoses and OMP tubes. Too much engineering required for nylon OMP tubes in this tight area so I just pushed on some vacuum tubes to the chopped OMP tubes (the PO did this but his rubber hoses had succumbed to oil).
After several minutes it was smoking a bit. Hmm, maybe oil in the exhaust burning off? So I reved it a few times. Man this revs healthy! Like a perfectly adjusted accel pump on a perfectly sized carb and intake manifold to the port area and timing. What a great match! EFI can't touch this.
So it blows a little smoke while reving up, but stops as the engine returns to idle. Hmm, if it was bad oil seals, it would pull oil past them under high vacuum which occurs as the engine slows back down to idle. What if the OMP is pumping too muh oil in? I can see oil flowing through the two lines going into the rotor housings. However I didn't see any oil entering the carb's OMP nipples. Maybe the OMP is acting up? I don't know at this point. Of course it IS a fresh rebuild with only 20 minutes of run time on it.
Oh and the smoke became less as I turned the idle from 1350 down to 1k. So being a fresh rebuild, I'm not too concernd right now.
The coolant temp got up to 190 degrees F and held steady so that means the cooling system is working. Ambient was 70-something today.
The oil pressure is around 40 psi at idle and shoots up to 80 when you rev it. T2 oil pump. 10w30 oil.
Even so, it started really easily and wanted to idle on its own a bit sooner than I was expecting. Turns out the idle is adjusted slightly rich on this carb. No problem.Then I realized the RE-SI OMP wasn't connected to the Nikki. No problem as no oil had made its way out yet. So I grabbed a couple of ends and pieces of vacuum hoses and OMP tubes. Too much engineering required for nylon OMP tubes in this tight area so I just pushed on some vacuum tubes to the chopped OMP tubes (the PO did this but his rubber hoses had succumbed to oil).
After several minutes it was smoking a bit. Hmm, maybe oil in the exhaust burning off? So I reved it a few times. Man this revs healthy! Like a perfectly adjusted accel pump on a perfectly sized carb and intake manifold to the port area and timing. What a great match! EFI can't touch this.
So it blows a little smoke while reving up, but stops as the engine returns to idle. Hmm, if it was bad oil seals, it would pull oil past them under high vacuum which occurs as the engine slows back down to idle. What if the OMP is pumping too muh oil in? I can see oil flowing through the two lines going into the rotor housings. However I didn't see any oil entering the carb's OMP nipples. Maybe the OMP is acting up? I don't know at this point. Of course it IS a fresh rebuild with only 20 minutes of run time on it.
Oh and the smoke became less as I turned the idle from 1350 down to 1k. So being a fresh rebuild, I'm not too concernd right now.
The coolant temp got up to 190 degrees F and held steady so that means the cooling system is working. Ambient was 70-something today.
The oil pressure is around 40 psi at idle and shoots up to 80 when you rev it. T2 oil pump. 10w30 oil.
07-19-14, 01:10 PM
#19
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today i get to put a new radiator in the Rx8, as the old one seems to have one more hole in it than it should :headscratch:
it kind of looks like a PITA to do, half the car comes apart (ok maybe like 1/8th, Peepers radiator comes out with 4 bolts...)
it kind of looks like a PITA to do, half the car comes apart (ok maybe like 1/8th, Peepers radiator comes out with 4 bolts...)
07-20-14, 03:04 PM
#20
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the Rx8 is weird... the SA/FB is like a normal car, radiator is just held in with bolts. the FD is this elaborate thing where everything fits exactly, but its also really easy to work on.
the Rx8 is sort of half assed. some of it is like a lego, so its super simple, but then some is pointlessly complicated. for instance instead of the tabs on the radiator bolting to little rubber bits, and then the body, the rubber bits bolt to tabs, and then the body, why the tabs? and then the wiring guy failed, there are little wiring harnesses running all over, when it could be one harness with a couple of branches... its an odd car?
the Rx8 is sort of half assed. some of it is like a lego, so its super simple, but then some is pointlessly complicated. for instance instead of the tabs on the radiator bolting to little rubber bits, and then the body, the rubber bits bolt to tabs, and then the body, why the tabs? and then the wiring guy failed, there are little wiring harnesses running all over, when it could be one harness with a couple of branches... its an odd car?
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03-17-22 02:46 PM