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 Post subject: Re: The GWTFFM
PostPosted: February 10, 2016, 4:31 am 
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My reasoning is that if a serpentine can support 33HP at 5K for an M90 supercharger, a dry sump pump running scavenge only should be easily fed.
As long as the shaft and bearing can take the tension load that is.

So keep the two scavenge ports under the pressure relief valves, and add a third on the front cover side, capping the one by the rear iron?

Image

Still slightly confused to be honest.

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 Post subject: Re: The GWTFFM
PostPosted: February 10, 2016, 8:07 am 
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Since you're keeping the stock pump and using all the DS pump stages for scavenge, you'll need 3 ports in the plate. The "capping" of one of the ports was if you were using the DS pump for engine supply, thus, leaving only 2 stages for scavenge. In that case, the most important 2 locations would be at the "back" corners.
Add the third one as shown and plumb -10 lines to the three inlets on the pump. The pressure stage most likely has -12 fittings, so change those out for -10s (both in and out).
The stock serpentine setups also rely on an active tensioner. So, if you don't have the space to add one of those, it may be easier to just go with a gilmer belt.


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 Post subject: Re: The GWTFFM
PostPosted: February 10, 2016, 8:34 pm 
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Oh, OK, so I shouldn't use the front cover relief as a scavange port as well, now I think I understand. :cheers:

The pump is set up for -12 all around, I'll have to look into getting fittings.

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 Post subject: Re: The GWTFFM
PostPosted: February 11, 2016, 1:29 am 
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Location: central Arkansas
300D50 wrote:
I intend to run premix, and will be keeping the stock OMP to supply oil on decel fuel cut if I can.

The metering valve on my old 12A was hooked to the throttle linkage, all mechanical. It wouldn't be rocket surgery to cobble up a microcontroller and metering valve substitute. With a separate oil reservoir you could use two-stroke oil, which is a lot less smoky and doesn't crud up the spark plugs.

Quote:
I'm not going to run a gilmer/cog belt, and likely will just use a serpentine.

Serpentine should be fine. And they're not finicky about getting road debris between the belt and pulley like a toothed belt. And if you pick your size right, you can have an off-the-shelf AutoZone belt instead of a special order from McMcaster-Carr.

Quote:
I have a few metric adapters I made for a Mercedes project a while back, and one of them fits the rear iron just purdy!

I opened up the straight threads on a Mazda oil cooler to NPT to use more-easily-available (then) NPT-to-AN fittings. I don't know what alloy Mazda used, but that was some of the toughest threads I've ever tapped...


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 Post subject: Re: The GWTFFM
PostPosted: February 11, 2016, 1:34 am 
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seven13bt wrote:
I'm not certain that a serpentine belt will be able to transmit the torque required by the DS pump.


Published sources run 5 to 15hp for automotive oil pumps in general. Depending on the width, serpentine belts can handle >50hp easily. Most belt-driven superchargers are using serpentines now.


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 Post subject: Re: The GWTFFM
PostPosted: February 15, 2016, 8:39 pm 
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Ok, let's start off by saying I found out at the end of January that I probably jumped the gun to the tune of nearly $500, and about 6 hours of machining time. :evil: :shock:

When I last made an adapter plate/flywheel spacer combo, I had a full cad model, including clutch and pressure plate, transmission (with input shaft), engine crank surface, release bearing, clutch fork, pivot ball, and everything was verified to work before anything started.

This time I neglected to check the throw on the release bearing, the protrusion of the input shaft, and a host of other things.
I think I was a bit blinded by the "happy happy!" of finding out the ring gears matched, and didn't check the big picture and big issue items.

In my zeal to get things finalized, I generalized that if the ring gear worked great, then I'd be able to use an aftermarket off the shelf flywheel, with only a spacer to adjust for the adapter plate thickness...
Cue ordering a $378 flywheel, $58 pressure plate, and $48 clutch disc, and machining up the following adapter.

Final touches, had a bad dimension for the depth of the counterbore that locates on the counterweight.
I had it as 2mm on the print, should have been 3.5mm. Easy enough to fix.
Image

M10x1x35mm flange bolts, to replace the 20mm ones that came with the flywheel. With the 13mm spacer they fit great, and didn't hit the rear stationary gear bolt heads. You can also see the locating lip for the flywheel.
Image

The counterweight side, with 77.86mm diameter counterbore and lead-in chamfer.
Image

Setting on the flywheel, before being pressed in.
Image

Pressed in, ready to mount.
Image

Mounted down.
Image

Side shot
Image


The clutch disc and the pressure plate came in back on the 29th, so after work I popped out to the shop and started the shenanigans that informed me of my possible major screwup.
Oddly enough, I was sent a sprung disc for a different Nissan by accident, but it turned out to be the same price, same dimensions/splines, and sprung, so meh. :?:
Image

I turned down the transmission centering shaft to also act as a clutch alignment tool.
Image

I stopped taking pictures after that, since they were going to be near identical to the flywheel install ones already shown.

It was after bolting the pressure plate and clutch onto the flywheel and setting the transmission back on, that I noticed I had no release bearing engagement.

That's when the penny dropped, and I swapped the alignment shaft for the input shaft (it's bagged along with the other guts to keep the case more manageable...), and confirmed I only had about 1/2" of spline engagement into the clutch disc. Image

When I removed the 1/2" bar stock spacers that are currently standing in for the adapter plate, I could get about 7/16" of engaged travel on the release bearing before the clutch fork bottomed out on the transmission case, and I had about an inch of spline engagement.

It turns out that while the Sentra flywheel may have the ring gear in the same ballpark location as the 13B, since it is a dual mass unit the clutch surface is quite a bit further out. From looking at the stock flywheel photos and scaling from known dimensions, it seems to be someplace between 12 and 19mm from top of ring gear to the clutch surface.

This means I'm going to need at least another 12mm of spacer, which puts me to 25mm on the low side. That means I'd need 45mm long bolts, witch is a little bit on the long side.

This has been gnawing at my brain since the 30th.

I'm torn between two options:
1: Buy a Sentra aftermarket steel flywheel/clutch/pp kit, and make an adapter to bolt it to the Wankel, and sell the flywheel/pp I bought.
2: Machine up the 25mm adapter, and see if I can get out of the pickle I got myself into.

Option 2 is cheaper money wise, since I have the stock, have the flywheel and pressure plate, and know where I went wrong.
The longer bolts have me worried, but I may be able to use press-in studs.

Option 1 brings a bit more uncertainty as to whether I can physically make the adapter, but then I know the rest of the clutch/starter/pp/release bearing will work properly.

I'm leaning towards option 1, but I'm unsure.

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Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.


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 Post subject: Re: The GWTFFM
PostPosted: February 18, 2016, 9:18 pm 
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It's not like you're prototyping for mass production. Make the spacer, use the 45mm bolts, and move on to the next problem.


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 Post subject: Re: The GWTFFM
PostPosted: February 25, 2016, 5:12 am 
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Well, I have another entire trans on the way, along with shift cables, shifter base, trans brackets, possibly clutch master, and some wiring pigtails. All stuff I was going to need anyways, with an extra transmission to play around with.
All of it from a front end wreck 05 Sentra Spec V that is getting parted out, so it should be same ratio and be a good spare.
Going to pick the lot up Sunday.
Guy said to bring tools and rip off anything else I fancy while I'm there. :mrgreen:
Now that I think of it, I can probably snag the drivers side CV axle for mockup purposes too.
It's amazing how great deals can come up at the most unexpected times.

TRX: I've decided to do blue loctite on the bolts, with very tight clearance holes in the new spacer.

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Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.


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 Post subject: Re: The GWTFFM
PostPosted: March 3, 2016, 6:34 pm 
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Ideally you want dowels to take the torque and bolts to provide the clamp load. Many "flywheel bolts" use the unthreaded shank closely fitting into a counterbore to get the effect of a dowel at lower cost.

You really don't want the flywheel, spacer, and eccentric shafts to move in relation to each other. Fretting can get ugly.

I'd at least dowel the spacer to either the eccentric shaft or flywheel, whichever is easier. That would eliminate one potential fret surface.


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 Post subject: Re: The GWTFFM
PostPosted: April 25, 2016, 12:58 pm 
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The spare parts fell through, not sure if the trans is still available.

Winter shut things down almost entirely, but spring is picking them back up a bit.

Had a departmental transfer at work back in March, which came along with a shift in hours to 10 hour days, 4 days a week, so that put a bit of a damper on things as well.

I'm going to machine the new spacer, and go from there.

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Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.


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 Post subject: Re: The GWTFFM
PostPosted: May 18, 2016, 6:44 pm 
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TRX, for some reason your "make it, move on" comment about the spacer stuck in my head the past few days, rattling around.

I decided to channel some work stress yesterday, and pounded out the new one when I got home.

No pictures of the process, since it was a "work on it till it's done, and don't give a rats patooie about documenting" kind of ordeal.

So now it's time to test-fit the thing and see what's what.

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Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.


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 Post subject: Re: The GWTFFM
PostPosted: May 24, 2016, 1:41 pm 
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"Damn the torpedoes, full speed ahead!"


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 Post subject: Re: The GWTFFM
PostPosted: May 24, 2016, 1:44 pm 
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Bolts came in yesterday while I was at work, now I have to wait till I get home from work Wed morning to test fit.

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Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.


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 Post subject: Re: The GWTFFM
PostPosted: May 24, 2016, 2:03 pm 
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:cheers:
f'ing torpedos....

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 Post subject: Re: The GWTFFM
PostPosted: May 25, 2016, 10:18 am 
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Photos commence!

A trip back in time to the 18th.

Turning the new spacer at home. Slow and steady on the South Bend Heavy 10.
Image

Later that day, after drilling the bolt hole circle on my lunch half-hour. Figured I'd use the DRO again, like I did when I made the last spacer. Takes out some chance for error.
Image

Side by side thickness comparison.
Image


Fast forward to this morning after I got out of work.

Torqued down, with M10x1.25x40 flange bolts.
Image
The 45mm long ones stuck out from the counterweight about 4mm, and I didn't like them that close to the stat gear or main seal. Good thing I bought both sizes, just in case.

Side view.
Image

A peak at the center. The flywheel is a 0.0005 press fit (I need to check my prints to be sure...) onto the spacer lip, and this should be the first, and last, time it gets pressed on.
Image

The bolts will get some loctite 242 (sky blue) on final assembly.

Clutch and alignment tool, as usual.
Image

Trans on top again, with input shaft stack in place to rough center. It's setting on 1/2" spacer blocks to stand in for the the 1/2" adapter plate.
Image

I forgot to bolt the pressure plate down, but it confirmed that the entire assembly cleared.
Image

I stopped taking photos after that, since they would be visual repeats of the last time I did a spacer check.

After tightening down the pressure plate, I also confirmed that I need to make a 9.5mm spacer plate for the starter, to get the bendix to clear the ring gear when retracted, and still mesh fully when extended.

While I was at it, I double checked axle shaft fitment, and everything seems to be in order, with the bearing mount flange clearing the front cover.

Also confirmed is that the OMP and the outside of the CV canister want to occupy the same spot, so it looks like I'm not running an OMP. I think the old linkage ones were skinny enough to fit, but the E-OMP is a big wart.

I should have an MDF adapter plate made sometime after the holiday weekend, to get confirmation that things line up and my design is valid.

Then it's finding some more fasteners, doing some more CAD work to devise a suitable driveshaft bracket, and yet more MDF.

Looks like the flat head M10x1.25 cap screws I need to mount the adapter plate to the engine are $6 each, if they are available stateside at all. Ebay.co.uk and ebay.ca, here I come.

EDIT: Found 2 sets of 5 each, M10x1.25x40 flathead cap screws, full thread. After shipping it came to $45.88 for all ten.

Cheaper than making them myself, and I can turn them down to exact size on the lathe. Yippee!

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Walt
06 RX-8 Shinka
04 RX-8 GT
06 325xi
Some people never have anything except ideas. Go do it.
Emissions & fuel economy haven't exactly been areas of strength for past rotary power plants, but absolutely no one with a soul has ever cared.


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