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PostPosted: November 11, 2010, 1:27 am 
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nether10 wrote:
I do like it, but I see one issue right away: your new output would be spinning backwards, unless you can figure out how to mount the existing crankshafts in backwards to put their output on the other side.
.


You can choose which end to have the flywheel on the dummy shaft.

Kurt, Yes harmonics could play into it thats why I am not considering doing my own V8, I haven't the foggiest idea about how to make a new crank from scratch that may have these issues and waste a lot of my money and time. I do know people who can resolve harmonic issues in this design though. This idea drives through a idle gear/dummy shaft which is a third element that can be engineered to cancel other elements maybe you twin crank was direct crank to crank?

Oldejack, yup the Ar-i-el Square four, they sold a few of them too but were always having troubles with them though not problems directly related to sticking 2 engines together.

Glad you guys like the idea, when I go back to Oz for Xmas I am going to try and hunt down a couple of old Busa cranks to bring here to see if it is economically feasible for this company..


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PostPosted: November 11, 2010, 6:20 pm 
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a.moore wrote:
motive wrote:
Personally I think a v-8 based on 600CC motorcycle heads sounds the coolest.


Would a 554cc v8 using 250cc heads suffice? :D

http://dot.etec.wwu.edu/fsae/viking30.htm
http://dot.etec.wwu.edu/fsae/v30/v30pics.html


Man if you're going to that much work at least use 750, 1000 or larger!

Plus, don't the larger displacements have a lower RPM? Easier to manage gearbox logistics with a lower RPM, I would think.

nether10 wrote:
Wow. I think someone else said it best on another forum I found in reference to this engine: "Why don't they just open source it?!?" No kidding! Please, someone release the data for it! I wonder what the power band for it looks like.

554cc may be a bit small still for even a Locost... but a nice 1000+cc V8 would just be sweeeeeeeeet.... If anyone has access to a 600cc bike engine they want to base a V8 around, I'll do your CAD work for that too.


Well, HAS anybody asked? :wink:

I visited WWU a couple weeks ago, the VRI(Vehicle Research Institute) is 2-3 dedicated professors. Interesting program, department all around. They were really great, helpful, open guys. Might as well ask!

Their current FSAE stuff isn't related at all, so competitive secrecy likely isn't a factor.

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PostPosted: November 11, 2010, 6:34 pm 
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JSullivan wrote:
nether10 wrote:
Wow. I think someone else said it best on another forum I found in reference to this engine: "Why don't they just open source it?!?" No kidding! Please, someone release the data for it! I wonder what the power band for it looks like.

Well, HAS anybody asked? :wink:

Yes! I did... about a month ago. I e-mailed the person listed on that site, and got a general error. I haven't tried again since (and, frankly, forgot about it entirely). I wouldn't be entirely surprised if the data has been lost, or is with the person who is no longer at the university.

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PostPosted: November 11, 2010, 6:51 pm 
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nether10 wrote:
Yes! I did... about a month ago. I e-mailed the person listed on that site, and got a general error. I haven't tried again since (and, frankly, forgot about it entirely). I wouldn't be entirely surprised if the data has been lost, or is with the person who is no longer at the university.


I'd try the faculty adviser. This is the guy I talked to. Seemed extremely upfront, I really liked him.

eric.leonhardt@wwu.edu

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PostPosted: November 11, 2010, 6:54 pm 
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Among the pictures, I saw one with several more blocks. So there may be 4 or more of those motors. I also saw a crank and block for a V12...

If you want to do this, maybe go back to engineering school!

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PostPosted: November 11, 2010, 9:59 pm 
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KB58 wrote:
There's also the not-insignificant issue of harmonics. Where I work we tried building our own twin-crank Diesel, and after several million on developement, we shelved it due to harmonics causing havoc on the crank and bearings. Just because something can be bolted together with existing parts doesn't guarantee no issues. Just sayin'.


Funny you should mention that - we were lightening F4i cranks for FSAE cars and ran into similar issues.

The company doing the work claimed to have many successful drag and sport bike people using their services with no issues, yet every engine we had with a lightened crank would always fail at the #3 rod and #3 main bearing. At first we blamed it on oil starvation but even after ensuring oil pressure was never dropping below 40 psi, we were still trashing engines.

We would usually replace the good engine with some pile-o-crap engine that was built using a honed block (thanks to scoring from a previous failure) and parts from other blown up engines. Since the cost of the engine was usually the cost of the new head gasket and bearings, no one ever took it easy on them. They got pounded relentlessly yet they never failed.

We were never smart enough to figure out the analysis but after reading several crankshaft design books, we decided that removing the weight moved the natural frequency of the crankshaft into the engine's operating range when installed in an FSAE car. The rev limiter probably didn't help help to prevent any weird harmonics from forming either.

Lesson learned: professional engine designers >> a guy in a garage with some tools

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PostPosted: November 16, 2010, 2:57 am 
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a.moore wrote:

The company doing the work claimed to have many successful drag and sport bike people using their services with no issues, yet every engine we had with a lightened crank would always fail at the #3 rod and #3 main bearing.

we decided that removing the weight moved the natural frequency of the crankshaft into the engine's operating range when installed in an FSAE car. The rev limiter probably didn't help help to prevent any weird harmonics from forming either.


Exactly why I don't just build my own V8, thousands of dollars designing and building a crank that may just go "bang" and there where do I stand. I even got a cheap source to forge/build the cranks just 20 minutes down the road too.


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PostPosted: December 23, 2010, 4:34 pm 
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So I have a spanner, and i'm throwing it in to the works here...

So, if we are planning this open engine project to be an i4, hows about this as something to ponder... Is there any way we could get insight into what the F1 guys will be doing for 2013? I know that they will be heavily guarded secrets, but maybe some basic ideas will be revealed, ideas that could possibly be borrowed.

Now I have no idea what those guys will come up with - how much more can you do to a basic i4 turbo? - but one thing is for sure, they are going to be throwing millions at wringing out ~750 horses from those little 1.6 FI engines so there is bound to be some cool new stuff that might be usable. (That or they just throw oodles of boost at the problem :( )

I know you would ideally want to base this thing on an already well established design, but what if we could base it on the next iteration of bleeding edge i4 tech?

I know there was no real content in what I said, it's just something else for us to think about...

Tom...


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PostPosted: December 23, 2010, 4:45 pm 
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i suspect we shall see even more use of powdered metals and ceramics. .. ceramic bearings have come a long way in the last few years and powdered metal rods are quite light. little tiny cylinders don't bang on them as hard so they may be able to rev up to a much higher limit, probably set by vibration rates rather than stress loads. i saw a white paper recently on forged piston inserts used in lightweight diesel pistons, that sort of technology spreads rapidly once its developed.

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PostPosted: December 24, 2010, 12:14 am 
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Nope, F1 have to use common alloys (although the matrixs are certainly nothing that we see daily) so you will not see ceramics per say but there is a bit of an opening for coatings - no more than 25% of the thickness and/or no more than 0.8mm thick.

FWIW the company I work with here's main line is CIP Cold Isostic Press which is used to press powered metals, ceramics etc. - in short throw a powder matrix into a rubber mould then throw it into a bucket of oil then pressure to 100,000+ psi and presto, one grainless forged part with the emphasis on grainless. Because no grain theres nowhere for cracks to start so it's a choice for making missile parts and for some reason we can't sell them to Pakistan, Iran or North Korea, don't know why ... !

See picture below of our latest we shipped 2 weeks ago, the oil is pressurized in the grey bucket and the arch assembly is to keep the lid on .....

Back to the engines, I don't want a turbo variant, can't stand the sound and don't like the drivability (lack of it) - just go turbo a Busa engine if thats what you want and very cheap too. Me I'll have a small 8cylinder I think, just for the fun and the sound.

Anyone seriously interested? Theres more than one way to skin a cat.


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PostPosted: December 24, 2010, 4:05 am 
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Tom17 wrote:
So I have a spanner, and i'm throwing it in to the works here...

So, if we are planning this open engine project to be an i4, hows about this as something to ponder... Is there any way we could get insight into what the F1 guys will be doing for 2013? I know that they will be heavily guarded secrets, but maybe some basic ideas will be revealed, ideas that could possibly be borrowed.

Now I have no idea what those guys will come up with - how much more can you do to a basic i4 turbo? - but one thing is for sure, they are going to be throwing millions at wringing out ~750 horses from those little 1.6 FI engines so there is bound to be some cool new stuff that might be usable. (That or they just throw oodles of boost at the problem :( )

I know you would ideally want to base this thing on an already well established design, but what if we could base it on the next iteration of bleeding edge i4 tech?

I know there was no real content in what I said, it's just something else for us to think about...

Tom...


Well besides the 120x40 mm bore/stroke and direct injection nothing else is new.


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PostPosted: December 24, 2010, 11:52 am 
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flat4 wrote:

Well besides the 120x40 mm bore/stroke and direct injection nothing else is new.


The rules are a long way from being set in stone but the layout at the moment is for an 88mm maximum bore.


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PostPosted: December 24, 2010, 2:57 pm 
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cool pic! gawd i miss being a full time field tech. .. i spend more time dealing with beaurocracy nowadays (as in "please hold" or waiting for someone else to process bits of dead trees) than anything else it seems. hopefully i can get back to doing what i like instead of being a desk jockey one of these days.

cheapracer wrote:
Nope, F1 have to use common alloys (although the matrixs are certainly nothing that we see daily) so you will not see ceramics per say but there is a bit of an opening for coatings - no more than 25% of the thickness and/or no more than 0.8mm thick.

FWIW the company I work with here's main line is CIP Cold Isostic Press which is used to press powered metals, ceramics etc. - in short throw a powder matrix into a rubber mould then throw it into a bucket of oil then pressure to 100,000+ psi and presto, one grainless forged part with the emphasis on grainless. Because no grain theres nowhere for cracks to start so it's a choice for making missile parts and for some reason we can't sell them to Pakistan, Iran or North Korea, don't know why ... !

See picture below of our latest we shipped 2 weeks ago, the oil is pressurized in the grey bucket and the arch assembly is to keep the lid on .....


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PostPosted: December 25, 2010, 9:38 am 
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Cheapracer, that CIP process is impressive. How is the resulting strength for common automotive products, such as con rods and pistons. Also how good is dimensional control?

Bill


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PostPosted: December 25, 2010, 1:28 pm 
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(a short soliloquy from amidst a field of poppies. ..)

50 ton pressure thats not so bad
(sip)
same process and equipment for ceramics and powdered metal
(sip)
ceramic coatings. ..
ceramics and powdered metal parts are both finish machined to final size
(sip)
time to go pee
(pause for the mpaa)
those teflon on ceramic seals hold up 10k hours on low to mid pressure pumps, i wonder. ..
ceramic coated babbit bearings, hmmmm
(sip)
why have the bearing separate, why not finish the rod end to the needed size before "cracking" the main bearing seam?
(sip)
i'd rather have this bottle in front of me. ..
(surely you know the rest)
a ceramic coated rod would result in lower windage. ..
a ceramic coated crank, sure it could happen
probably not worth it
(sip)
now that would have less windage, the oil droplets wouldn't have anyplace to congregate
(celebratory sip)
glyphol coating the block is an old tradition
would a ceramic big end bearing surface hold up? hhmmm. ..
(sip)
seems like a bearing insert would introduce weakness because of stacked tolerances
definitely a reason to machine the finished bearing surface onto the rod but it would mean custom machining each one which would explain why oems don't do it
(sip)
poppies poppies poppies
(sip)
no grain means no torsional strength...
(sip)
didn't vegnolia make some ceramic pistons we almost decided to put in martins fiat?
hmmm
didn't they have some kind of hardened insert?
(sip)
so if someone had access to one of these machines they could maybe run a batch of pistons and rods...
the finish machining should be easy
frank used to hand finish main bearings with the bearings installed in the block and a boring bar
heck frank made bimetal bearings from raw materials
(sip)
here's to ya frank, you were a pretty neat character
those were great impromptu lessons you gave whenever i showed up, i remember almost every detail of that packard 8
(in 1938 frank turned 18 and joined the navy. he was a machinist for the rest of his life, ran the shop for old man harrah way back when, probably best known for what he could so with a model a engine. for some reason the narrator is starting to sound like tom waits. ..)
(hic)
(sip)
i wonder....
if a billet crank is ~$1800 out the door what would a set of custom rods run?
i've dropped $5k on an oem engine before so maybe???


(gotta be something to do during the commercial breaks right?)

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