Eccentric Shafts: OEM vs. Xtreme Rotaries vs. KIWI RE?
 

So does anyone have an experience/information on the use of a two piece eccentric shaft versus the stock OEM unit? Ran across two units that caught my eye, one from http://www.kiwi-re.com/wwd_showroom_cat1_1.php and the other from www.xtremerotaries.com (scroll down about 1/2 page).

Besides costing more (about $2,100 for the KIWI unit and $3,000 for the Xtreme Rotaries one), would these in theory be better than a balanced OEM one?

Thanks for the input.

Lots of people use the stock shaft in excess of 650 rwhp. Mandeville said the key to longevity is that it is dynamically balanced properly. This is critical to the bearing life. He also said there are only a handful of people that do it properly. People send him 3 and 4 rotor rotating assemblies from all over the world. He recently told me about a rotating assembly that was 'balanced' by another shop and was a total mess. He said my late model D-series rotating assembly can be safely run at 10,000rpms with a sufficient oil pump. He said the bigger factor is block flex.

Not sure I see a limitation that you should be concerned about. Why are you asking about this?

Ran across these and was curious if this is a good option for the future when needed.

OK, I can't tell you which but one of the aftermarket shafts was so good that Mazda USA sell them as a factory race part since supply from Japan has dried up.

Back in 2005, both companies sent demo shafts to Mazda. Only one was approved.

Personally, if I wanted the best quality shaft for my engine. Price would not be the deciding factor.

REgards

^Price isn't the issue for me. Don't get me wrong on this, I don't spend just to spend. What I mean is I don't mind paying extra IF something will work. Not sure the shaft is worth the extra money. I'm not running over 700 WHP so I don't know if it matters.

That's what I'm asking. Does this make a difference in a street build and at what level?

Call Steve at MPS he may have one for sale.

For those interested, I have 2 Brand NEW NOS "NEW OLD STOCK" 20B E-SHAFTS. $1800.00 each. Exspensive but still cheaper than the aftermarket KIWI or Guru shaft.....and its OEM MAZDA

As usual, CMonakar's right on the money. And not cuz he's some super smart fellow (although I'm sure he is regardless). Rather, it's b/c he was able to inherit a *wealth* of info from another rotorhead who'd done all the research on the 20B route too. Add to that the wealth of info CMonakar's been through *himself* w/ his 20B fiasco (hehe) and you can see why if it's been asked, he probably knows the answers ;)

David, to just make one further point, while e-shaft flex is a concern at the 9,000+ rpm range (that's where the concern BEGINS), the problem is the HOUSINGS themselves begin to flex around the 8,000 - 8,500 rpm range. Remember that due to the longer length of the 20B block, it's characteristics are NOT the same as a 13B (which many often overlook).

Also, from the info I've received (all from professional 3 and 4 rotor builders & racers), what most ppl deem as "sufficient" oil lubrication in a 20B making considerable power is ghastly inadequate. So that's probably what I'd make your primary concern ;)

Well you're in luck, because I can hehe.

Jeff Bruce makes the parts for Kiwi, and his e-shafts are also sold through Mazda(comp) as OEM replacement. He also makes two- and three-piece shafts as well. But keep in mind that (as CMonakar hinted to), the center bearings on multi-piece shafts tend to see more wear, and as such can leave ya tearin down the block regardless... So it's def. not the end-all be-all...

~Ramy

So the 20 E-shafts Mazda Comp is rumored to have must be the Jeff Bruce E-shaft...and is the price really $6000.00 each? The guys @ Mazdatrix told me, last time I was there that, Mazda had the Thick center Iron (quanity unknown, new tooling, re-engineered)and 20 (NEW tooling, newly Engineered) E-shafts... I was told the Thick center iron was going to be $2400.00 each...

Dude I dunno who the heck told ya they were $6K. The price I was quoted was a bit cheaper than Mazda(Comp). But as always, that's always based on who you know, and if you go directly to the source vs. via a middleman (or two, or three lol).

Also, the regular e-shaft (which like you heard has been beefed up a bit) is very different than the more expensive multi-piece e-shafts that Jeff makes. So don't confuse the pricing on those (although not even the 3-piece units were anywhere NEAR $6K).

When I talked with Kiwi, and extreme rotaries, they told me there is no 3 piece eccentric shaft made. This is interesting news, how do you get in contact with jeff bruce on the pricing and such of the 3 piece 3-rotor shafts?

Mandeville = truth

Being that I gots one in stock, I think it's fair to say they're definitely made ;) Also, it's kinda weird cuz Guru (Xtreme Rotaries) was supposed to be coming out w/ their 3-piece. I guess since Jeff beat 'em to it, they didn't bother...

He doesn't sell to the West directly. Shoot me an email. I can sell 'em to ya ;) Info@FDNewbieImports.com.

~Ramy
FDNewbie Imports

^Ramy, what's the difference between your three piece shaft and and a "new, old stock" OEM one? Basically a new one from a D series design? Also, this has been posted in another thread but should the numbers on an engine's eccentric shaft match the numbers on the rest of the engine components? My C series engine components all have matching numbers on all of hardware EXCEPT the e shaft. Does this mean the e shaft was swapped out? Can I use the e shaft number to verify what series engine it is from?

Jeff Bruce's...not mine ;)

One's one piece (OEM), and the other is actually 3 pieces (designed to eliminate e-shaft flex at higher rpms, which again, isn't really a concern unless you're building a race motor that will rev that high and is built to withstand the BLOCK flex you'll experience prior to having to worry about SHAFT flex).

I'll defer that is a question to the pros...ppl like DMRH who were messing w/ 20Bs while I was still in elementary school :p:

~Ramy

I am pretty sure you meant to say OEM 2 piece design..the factory OEm mazda shaft is already 2 piece.... And Ramy, you said you have one of the 3 piece Jeff Bruce e-shafts...right.. can you post pics and a price for it?? I want to know how much the 3 piece shaft cost..

Just to clear things up a little.

Precision engineering shafts are sold (sometimes) via Kiwi-RE

Xtreme rotaries shafts are sold via any "GURU" outlet

The comment about the Mazdaspeed shafts are actually the "Precision" ones is interesting because its certainly different to what I have been told & researched.

I'll go back to the source now & double-check. I would have stayed quiet if the "Guru" name was let out of the hat but since the wrong?? answer popped up. I'm forced to check it out now.

I'll get back once this question is cleared up. As I dont think Steve Sanders would be moving both compainies shafts

REgards

My bad

I'm traveling right now, so pics I can't do. Shoot me an email for price plz.

I was under the assumption they were the same entity? The website used to say Guru Motorsports, but a year or two ago (roughly) it said Xtreme Rotaries, and the URL even directed to that. So again, I assumed they were one and the same? :scratch:

I was told that as a direct quote, and was shown documentation. It was at least a year ago though. I'm sure I have the info somewhere (also at home).

I hope I didn't confuse you? Again, I was assuming Guru & Xtreme were the same thing.

~Ramy

You cant be traveling forever... Please post the pics of this 3 piece shaft you have as soon as possible..

Thanks BG

^So, anyone know where to get a new OEM shaft from?

Going to be hard..

I still have the one extra Brand New OEM shaft.. but I doubt i will sell it...

^Taunting me are you?:) Does this mean I'll need to go the Kiwi RE or Xtreme Rotaries route? How about center bearing assemblies?

Not tauting you at all.. I had that one other new shaft and I held out for you as long as I could.. The guy that bought it from me was Calling me and emailing me 5 to 10 times a day about it.. most persistant person I have ever come into contact with.. I simply got tired of him bugging me about it...

I can set you up with a New center bearing/stay gear as I have a few of those left...

David @ this point you should pick up a spare motor for parts so that you will have spares for your setup... The motors are drying up in Japan and soon we will see the price for a good longblock jump up a few thousand.. I am predicting in the next (12 to 48 months) the price for a good compression C or D code to be retailing for $5500 to $6500. This is the main reason I have dropped stocking/buying S4/S5 TII and FD Jspecs from my vendor in Japan. I have recently invested a huge part of my savings in 20B's. I doubt I will corner the market but I will not be left out either... And I will never have to source discontinued parts or have to shell out big money for the aftermarket stuff.. Something you may want to consider yourself.. I keep preaching this to the guys who are running 3 rotor engines.. some have listened some have thumbed theirs nose at me...

Like I said, I'm traveling. I'm abroad. I've been abroad for a few weeks. Won't be returning for another few weeks. Not forever, but not exactly overnight either.

And as I mentioned, feel free to email me for a price.

David, if Japan2LA doesn't sell you his, lemme know. I have a spare brand new one laying around at home as well...but I'd wanna make sure I can get another one to replace it first haha.

~Ramy

Thanks guys. I should know for sure next week about this. I appreciate it!

No rush Ramy, I simply want to see the E-shaft... not worried about the price.. I am sure I can afford it...

Then easy on the large orange font! LOL

I'm sure you can.

Someone has to keep you awake around here.. When you have time...

Zzzzz (lol)

Zzzzzzzzzzzzzzzzzzzzzzzz.

Any pics yet?

Jackson

CARLOS!!!!!!

:p:

Since I've spent most of this day on the computer,
I will shime in and clarify some speculation.

Note: WHAT DICTATES the number of pieces on en ecentric shaft is the NUMBER OF MAIN BEARINGS. period.

That been said,
EXCEPT for "Mechanicals Power system's" propriatary 3 piece, 4 Main bearing shaft.
There has never been a 3 piece Mazda 3 Rotor shaft.
Not Guru's, Not Presicion, not any one else has manufactured a 3 piece / 3 Rotor E-shaft

Only Steve from MPS, has made a few 3 piece shafts w/ 4 main bearings and only
for in-house

Both Mazda and Presition make or have made some 3 piece 4 Rotor E-shafts, but again
4 Rotors.

Yashiro Engineering out of Japan has bult and tested what is believed to be a "4 piece", 4 Rotor engine, and for a FACT has (5) main bearings.
The extra one placed between # 2 & # 3 just like the Guru's 2 piece, 2 Rotor.
Although it is believed to NOT to be a Roller as in Guru's own but rather a plain bearing just like in all the Stationary Gears.

MPS, places a plain bearing between # 2 and # 3 in the narrow center steel plate.
Making for a much reduced "Sling" effect of having 2 Rotors unsuported when side by side.

Below's illustration shows a side by side comparison of a Mazda OEM 20b E-Shaft, and a Presicion shaft from Down Under.

http://img.photobucket.com/albums/v1...pare1.jpgM.jpg

The photo clearly shows the difference of both shafts and the thinner section
between # 2 & 3 of the Presicion shaft.
This mainly accouts for the nearly 2 pound lighter weght of the Auzy.

This next photo illustrated were MPS. installs the 4th Main bearing, and therefore nessesatating the build up of his shaft in 3 separate sections for their 3 Rotor shaft.

http://img.photobucket.com/albums/v1...24266.jpgM.jpg

Money been NO OBJECT, this one wins hands down

In my opinion: CLEARLY A WORK OF ART ! :icon_tup:

GT1-20b

Finally, Thanks Carlos..

I was really finding it difficult to believe that the Jeff Bruce shaft was 3 piece.. This was the main reason why I kept bugging Ramy to post pics of the shaft he said he had in his inventory...

So the only 3 piece E-shaft is also a 4 bearing journal shaft ... That shaft is the MPS shaft built by Steve in canada

The Jeff Bruce shaft is a factory replacement which is well made and is machined a bit more to take some weight off...

How much is the MPS shaft ?
How much is the Jeff Bruce shaft?

I respect Carlos and his knowledge 100%, but I can tell you for a FACT that I have spoken DIRECTLY with both Jeff Bruce and one of his affiliates here in the US NUMEROUS times, and Jeff Bruce sells BOTH a "Replacement 20B shaft assy" and a "20b shaft assy, 3 piece with extra needle bearing assy." That's a DIRECT QUOTE from what he and his associate have shared with me IN WRITING. Now I'm not the most knowledgeable guy when it comes to engine internals, so I won't speak about what I saw. But I will say that the above leaves us w/ only one of 3 scenarios:

1) Jeff Bruce has an e-shaft that Carlos doesn't know about
2) Jeff Bruce is reselling the MPS shaft
3) Jeff Bruce is a liar

Take your pick ;)
~Ramy

Not sure if you are still abroad but.....

you said earlier in this thread......... " I gots one in stock" and I was under the impression that you where talking 3 piece 20B e-shaft that Jeff Bruce manufactures... maybe I mis-read or something?? This is the shaft I and a few others here have been waiting for you to post pics of..... and pricing

Maybe you can explain?

Yes, I was indeed speaking of the 3-piece shaft. And I do have 'em in stock. But a) I am STILL traveling at the moment, as I have clarified to ya THREE times now...I've been away for over a month, as I have more important personal things to attend to, and b) I don't store the e-shafts myself. An e-shaft isn't something you want being shipped back and forth. You want it handled as few times as possible. That's why the e-shafts are obtained directly from Jeff Bruce and kept in one facility. There, they're placed on a special fixture and checked for dimensional stability through a CNC digitizer. From this procedure all lobe and journal dimensions are recorded in relation to the centerline of the shaft.

Why? Because during processing, shipping and other handling, a 3 rotor shaft can easily be knocked out of alignment with the centerline of the shaft. The result? A customer puts together an engine and the rotor hits the housings. We currently make it a practice to check and document the procedure. When the shaft leaves the facility, it's right and it's documented.

Moreover, the shafts sit in a controlled environment (light, heat, etc). Yes, we take these e-shafts VERY seriously.

As for pricing, like I said, email me if you're interested. If you just want a ballpark figure, it's a bit over $3,000, FOB.

~Ramy

That's very good to know.
Many times I've seen so called supplier's idea of a good shaft turned into a nightmare once runout is checked. I have a couple of those laying around you can use for desk ornaments.

Is my assumption correct that the e shaft is not the weak link in a street driven setup, say up to 600-700 WHP? My understanding is the e shaft and flex comes into play when you want to take the car above 8,500 RPMs.

EXACTLY. Most people don't recognize that this heavy piece of steel can actually be damaged.

Shafts previously sold into the US directly from Jeff created many horror stories. Jeff would ship them out in a cardboard tube, much like a printed poster. Too many arrived with no end caps and the cardboard crushed. So it became a priority to create a reasonable alternative. Now, a special container is actually sent to Jeff for the shafts to be shipped back in.

The good news, however, is that a shaft can be straightened. This includes the original Cosmo shafts. Mazda had a similar problem four years ago. When you get your shaft from us, it will come with a sheet that gives you the runout numbers. No shaft that has ever been made is perfect. It documents the condition it leaves in. We install the shaft into a PVC sleeve with endcaps and support the ends from movement.

When an engine is assembled, the normal process is to turn it over as it is assembled (not with a starter motor after it's in the car). The customer doesn't need to go through the extremes we have to. Simply set the shaft on vee blocks with a dial gauge and check the shaft.

Unless there is a broken package, the freight carrier usually won't be any help. Remember that the center bearing shaft is made in three parts. The center of the shaft that contains the keyway is much smaller than the rest. Correction is pretty simple in concept.

These are lessons learned, and why we take it so seriously.

David, in short, housing flex is the more primary issue you'll face, well before you face any issues w/ e-shaft flexing. For you to face issues w/ e-shaft flex, you'd first have to have a purpose-built block to address housing flex...and that type of block has NO business being on the street ;)

~Ramy

Just from the way a shaft is stored can cause problems.


That depends on the individual involved. :lol:

Jeff Bruce does indeed make a 3 piece 20B eccentric shaft. Its available as either a 'long' shaft (thick intermediate housing) or as a 'short' shaft (thin intermediate housing).

As mentioned above, the extra bearing is a needle roller and is fitted to the 'empty' intermediate housing, thus eliminating flex in the un-supported 'long' section of the shaft.

Here is the 2 rotor 2 piece, imagine an extra removable lobe for the 3 piece.

Very true.

Yes, I know there are some psychos out there *ahem* :p:

All the above is true. It's a proprietary design, high strength steel 3-piece shaft designed and machined by Steve at Mechanical Power Systems (www.mpsys.ca) himself. Unlike the other three piece shaft offering, this one uses an OEM Mazda bearing pressed into a custom machined housing, which is in turn machined into the 40mm intermediate plate between the rear and centre rotor. Some key advantages of this shaft over others is the sheer strength (and I guess shear strength too :p) and rigidity allow for a sustained rev-limit of 14,500rpm+ (with supporting engine modifications), and power figures well into the quad digits. Imagine the power potential that could be unleashed with a usable rpm range like that in both NA and turbo, road race and drag! This shaft is the real deal if you are serious about making power!!!

However, I believe his reason for not producing these was that he was doubtful of the market potential. If this became available again, would any of you be interested? There would be many configuration options and packages available, including required centre plate machine work/modifications, high strength counterweights options, as well a proprietary e-shaft/counterweight drive design.

How many of you would invest in these parts if they were readily available?

I can confirm that this is NOT true.

Well, I would be interested.. I have been waiting for the E-shaft Ramy said he has in his inventory to materialize to no avail, so I will move on.. Price on the E-shaft and all the parts needed to make it work please.. and pics would be great too.. Please advise..

I think a few people would be interested. . . I know I would pending answers to J2LAs questions.

Any info?

Same thing I have been thinking.. Ramy said he had the E-shaft and would post pics.......... said he was traveling abroad.... Myself and few others are still waiting for him to post the pics.. probally will never happen.


On the other hand, B6T from CANADA sounded like he could deliver...maybe he will be kind enough to come back and update us..