Author Topic: BSA B50 -500 APG Build  (Read 460948 times)

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Offline wobblywalrus

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Re: BSA B50 -500 APG Build
« Reply #630 on: November 17, 2013, 02:25:07 PM »
Think about the cumulative years of racing experience on this site.  It must be incredible.

Offline Koncretekid

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Re: BSA B50 -500 APG Build
« Reply #631 on: November 18, 2013, 09:26:54 AM »
Tom, I have very little to add to the envelope................but did glean this from some drag-racer conversation. You could run the SC from the clutch, the tranny, or a jack-shaft on the chain. The latter would tend to slow the SC down and give you better control. Another discussion revealed the rider installed a switch on the shift-drum so his ELECTRIC SC would only run from 3rd gear and up.

I think your existing RAM-AIR system is a significant contributor to your speed.
Dennis,
I agree with Nortonist that the electrically driven supercharger would not be allowed.  Running the SC off the drive chain sounds like a nightmare to get the jetting correct, as the boost would not be relative to engine speed.  Also, the Rotrex charger that I was looking at likes to be driven at speeds up to 19,000 PPM, which would be difficult with any drive system other than crankshaft driven.  That being said, if you look at the primary drive on the BSA, you will see a hex shaped spacer where the rotor used to live.  I think I could modify the cases sufficiently to place the end of the crank outside the primary case and put a pulley on the shaft driving either the SC directly(preferable) or a jackshaft.  Rotrex make a small C8-8 charger which would provide up to .065 kg/sec airflow, or up to about 75hp.  It can be had in CW or CCW format which could also be a real bonus.  It has its own internal oil pump which of course requires an exterior tank and radiator, but that's doable.  I think my 500cc motor in normally aspirated format consumes about .04 kg/sec airflow, so .065 kg/sec would be a nice boost, maybe as much as I would want to use on the old girl.
Can somebody give me a short course on reading the compressor maps?  Rotrex provides these in their literature?

Ironically, the best photo I have of the primary drive is the one showing blown primary chain, but you can see the possible drive from the crank.  The other photo shows what would seem to space for a SC below the carburetor, although this photo is of a stock motor.
We get too soon oldt, and too late schmart!
Life's uncertain - eat dessert first!

Offline charlie101

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Re: BSA B50 -500 APG Build
« Reply #632 on: November 18, 2013, 11:35:17 AM »
You might find an idea here. The Norton is of course not the same as yours. The Alton starter is driven with an extra chain and placed on top of the gearbox. You might find space to fit it outside your transm. chain or perhaps move that out a row?
http://www.alton-france.com/ekitnorton.html

Offline Nortonist 592

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Re: BSA B50 -500 APG Build
« Reply #633 on: November 18, 2013, 06:08:22 PM »
Think about the cumulative years of racing experience on this site.  It must be incredible.


I think "arthritis" should be substituted for "racing experience". 
Get off the stove Grandad.  You're too old to be riding the range.

Offline wobblywalrus

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Re: BSA B50 -500 APG Build
« Reply #634 on: November 19, 2013, 10:02:39 PM »
Tom, pressure enhancement was something I am looking at in the future.  Advice given to me by experts on this forum is a turbo.  It makes sense.  The power driving it would go out the tail pipe, otherwise.

The book "Engine Math" by John Baechtel ISBN 978-1-934709-47-4 is available and it has a chapter on reading maps, etc.

Offline Nortonist 592

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Re: BSA B50 -500 APG Build
« Reply #635 on: November 19, 2013, 11:45:39 PM »
I like that term "pressure enhancement".    I just sent of a check for an Aisin AMR300 supercharger.  I've had a bee in my bonnet for a while now to put a blower on the Weslake.  This one showed up so next year will be in the blown class.  Having zero experience with blowers it should make for a fun learning curve.
Get off the stove Grandad.  You're too old to be riding the range.

Offline JimL

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Re: BSA B50 -500 APG Build
« Reply #636 on: November 20, 2013, 12:10:29 AM »
Tom, during my years working with field diagnosis at the dealers, we learned to trust actual airflow measurement.  We found the correlation between measured airflow and actual power was pretty good, especially on well mapped engines (it was all production stuff, of course).  Stay with me, here, you'll see where I am headed a little further down...

There were two keys to our diagnostic work:
- did the peak airlow measurement (non-supercharged) calculate to the factory power curve, and then appear relational with supercharger fitted?
- for either mode, does the airflow graph (using wide open throttle from minimum useable rpm) exhibit linear change?  

Bumps or sags in the power curve, accompanied by changes in dBG of intake harmonics, signals a problem in the airflow measurement at the hot wire.  This was usually caused by loose or badly shaped intake components or chambers.  If something creates pulsing or turbulence in the airflow, the AFM will have ranges of inaccuracy and engine performance will be non-linear throughout the powerband.

Two formulas worked well for a healthy system:
- 1lb/min airflow x 10 = HP
- 1.32-1.42 x grams/sec = HP (example- a 4-cylinder Camry idles at about 2.5-3 gm/sec or less than 5 HP)

The beauty of positive displacement blowers is that you can choose your horsepower target (based on airflow desired) and then choose an appropriate blower volume based on the maps provided.  If you find a need for a little more airflow (boost) through the midrange, but need some control at high rpm WOT, the solution is a simple restrictor plate ahead of the blower intake.

We had some very satisfactory results using a little more blower, held in the best boost-to-temp ratio of Eatons maps, with the intake restricted in the upper part of the power band.  That is how you can keep more compression ratio in the engine without breaking ring lands from high RPM detonation.

Restrictor plates are a great way to ease yourself into reliable power, taking small steps at a time.  They take away little or nothing when the engines are below the redlne, but ramp back cylinder pressure when the intake event duration is short due to very high rpm.  You also take some of the biggest load off the drive, in the blower speed ranges where surprising stuff may come apart.  Changing drive ratios can be helpful, but that changes the entire operating range.

For those who wish to work in a more controlled supercharged environment, positive displacement blowers can serve us well and be a little easier on our wallets.  I hope there is something useful here...I only worked on these problems after someone else had made the important choices.

There I went again...rambling on and on....
Regards, JimL
« Last Edit: November 20, 2013, 01:09:04 AM by JimL »

Offline JimL

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Re: BSA B50 -500 APG Build
« Reply #637 on: November 20, 2013, 02:02:56 AM »
A little more from my old pencil notes in back of my company Franklin.

The M62 Eaton map shows 600 cubic meters/hr air flow at about 10,000 rpm.  That works out to about 2.64 lbs/min, which would be coming up on 264 HP.  On the Tacoma 3.4L V6 kit, the best I saw was around 23-24.5 lb/min.  I cant remember what the power loss was in driving that blower, but it got big if we overspooled it while driving intake temps up.

On my sons '78 Corolla Liftback (with 3.4L V6 installed) we ran a smaller pulley on the blower with six-rib belt and non-turbo 2JZ Supra fuel injectors.  That car was reading 29-30 lb/min airflow on the rev-limiter in 5th gear (139 mph on the 71 freeway at 2:00 AM.).   We were spinning that blower 12-13000 rpm and I used an adjustable intake temp signal to the ECM to get the timing back and fuel up.  The Eaton map shows we were unable to use the volume available from the blower.  No surprise with stock cams, etc, and a good demonstration of the non-linear power increase from trying to get too much compared to the standard kit.

The biggest "bang for the boost" really happens in the first 4-5 psi range.  After that, it becomes diminishing returns until you get to the point of blower or piston damage.  Keep in mind that if you try to pump more air than you can use,  the blower will start recirculating its own heated air around the rotors.  You can seize one doing that...another reason to consider starting with a restrictor on the inlet side until you can get it sorted out.

I apologize that I dont have better calculation methods for you, but my experience was mostly limited to this area, after the engineering was done.

JimL

Offline Koncretekid

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Re: BSA B50 -500 APG Build
« Reply #638 on: November 20, 2013, 07:21:44 AM »
Tom, pressure enhancement was something I am looking at in the future.  Advice given to me by experts on this forum is a turbo.  It makes sense.  The power driving it would go out the tail pipe, otherwise.

The book "Engine Math" by John Baechtel ISBN 978-1-934709-47-4 is available and it has a chapter on reading maps, etc.
Bo,
I've never found anybody that could make a turbo work on a single cylinder motor, but maybe that's because they weren't using a large enough plenum.  Then again, a large plenum with a draw thru carburetor makes a pretty big bomb, so a blow thru system might work with a large plenum.  Can you find anyone doing that successfully with a single cylinder motor?
I like that term "pressure enhancement".    I just sent of a check for an Aisin AMR300 supercharger.  I've had a bee in my bonnet for a while now to put a blower on the Weslake.  This one showed up so next year will be in the blown class.  Having zero experience with blowers it should make for a fun learning curve.
Nortonist,
Where did you get your AMR300? From what I've read about the AMR300, it produces about 300cc per revolution.  You'll need about 600cc every other revolution, or 300cc per revolution but won't get any boost at that.  So it seems you need to overdrive it, and it's a CW rotation blower, I believe, so you might want to use a jackshaft across the motor which would both reverse the drive direction and allow for overdrive.  Your installation should be similar to what I would need, so I hope you'll keep us posted. Are you planning draw thru or blow thru?
Tom, during my years working with field diagnosis at the dealers, we learned to trust actual airflow measurement.  We found the correlation between measured airflow and actual power was pretty good, especially on well mapped engines (it was all production stuff, of course).  Stay with me, here, you'll see where I am headed a little further down...

There were two keys to our diagnostic work:
- did the peak airlow measurement (non-supercharged) calculate to the factory power curve, and then appear relational with supercharger fitted?
- for either mode, does the airflow graph (using wide open throttle from minimum useable rpm) exhibit linear change? 

Bumps or sags in the power curve, accompanied by changes in dBG of intake harmonics, signals a problem in the airflow measurement at the hot wire.  This was usually caused by loose or badly shaped intake components or chambers.  If something creates pulsing or turbulence in the airflow, the AFM will have ranges of inaccuracy and engine performance will be non-linear throughout the powerband.


The beauty of positive displacement blowers is that you can choose your horsepower target (based on airflow desired) and then choose an appropriate blower volume based on the maps provided.  If you find a need for a little more airflow (boost) through the midrange, but need some control at high rpm WOT, the solution is a simple restrictor plate ahead of the blower intake.

For those who wish to work in a more controlled supercharged environment, positive displacement blowers can serve us well and be a little easier on our wallets.  I hope there is something useful here...I only worked on these problems after someone else had made the important choices.

There I went again...rambling on and on....
Regards, JimL


Jim,
I see that I need to go back to school on this subject!
Tom
We get too soon oldt, and too late schmart!
Life's uncertain - eat dessert first!

Offline Tofu

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Re: BSA B50 -500 APG Build
« Reply #639 on: November 20, 2013, 07:53:10 AM »
I know its not a four stroke but the Buddfab 50cc streamliner is a very effective turbo single at 233 km/h.
http://buddfab.net/buddfabhomepage.html

Offline JimL

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Re: BSA B50 -500 APG Build
« Reply #640 on: November 20, 2013, 11:54:40 AM »
Looks like I screwed up my math.  :oops: The power calcs I showed, based on actual vehicle driving and testing, were right.  

The 10,000 rpm blower calc I did was wrong.  It should have showed a "best case" possible 35 lbs per minute, which would be about 350 hp worth of air available at that rpm.  This jives with what people actually do, at various companies.

Thats what happens when a layman tries to figure out why something actually works!  I realized the Eaton map was talking cubic meters....like... 2/3 of a mile square and 2/3 of a mile deep.  Thats a big pile of air!

Anyway, that 300cc blower is close to a third of an M62, so I would guess it could be run up in the 100 HP area without getting it too hot.  It might need a bypass at low rpm, or the engine will have to be spun fast to start up and wont keep itself alive with the throttle mostly closed.

If you use a vacuum controlled bypass actuator it might need to be controlled (dampened) so it doesnt slam into boost flow too suddenly.  I used about a 0.060" orifice on the piece I worked up for the 3.4 V6 kit development.  Keep in mind that the blower and the engine are both pumps.  When the blower inlet is mostly closed, the engine inlet is not...it pulls the air out of the blower to form a larger vacuum chamber.  If you open that chamber instantly, the fuel metering gets goofy.

On our efi, I was seeing the AFM voltage spike above 5.3 volts (using a portable digital oscilloscope).  The ecm thinks it is working with a 5V device that should never exceed 4.9 volts in real world operation.  Because it cant calculate a 5.3 volt signal, aginst a 4.95 volt reference, it shuts off the fuel injection until the airflow becomes "real" again.  Customers dont like stumbling away from stoplights in a series of jerks and jumps!

I hope anyone who read my mistaken calculations kept reading this thread.  Sometimes I know how to make something work, but just cant explain it sensibly.  Mostly, you just have to keep trying until you get it or go broke.  This will be a good place for me to stop adding to the confusion. :|

Wishing you fun and success
Jim
« Last Edit: November 20, 2013, 12:11:38 PM by JimL »

Offline Nortonist 592

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Re: BSA B50 -500 APG Build
« Reply #641 on: November 20, 2013, 12:01:07 PM »

Nortonist,
Where did you get your AMR300? From what I've read about the AMR300, it produces about 300cc per revolution.  You'll need about 600cc every other revolution, or 300cc per revolution but won't get any boost at that.  So it seems you need to overdrive it, and it's a CW rotation blower, I believe, so you might want to use a jackshaft across the motor which would both reverse the drive direction and allow for overdrive.  Your installation should be similar to what I would need, so I hope you'll keep us posted. Are you planning draw thru or blow thru?

Tom
[/quote]

I've been looking for a while and this AMR300 showed up just up the road from me.  I'm in SoCal and the blower was in Sacramento.  I'm planning a draw thru.  If its OK with you I could post on here as anything I might post would be relevant to singles.  Just remember I'm no JimL.  I'm more in the "I tried it and it worked but don't ask for how in mathematical terms".

Give this place in Oz a shout.  They have an AMR500 for sale very reasonably.  I was going to buy it except there was a glitch on the site.  I emailed the guy and it took him a few days to get back to me.  In the time gap the 300 showed up so it should be still available.

www.sssautomotive.com.au

He seems a genuine guy and his prices are great.

Get off the stove Grandad.  You're too old to be riding the range.

Offline generatorshovel

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Re: BSA B50 -500 APG Build
« Reply #642 on: November 20, 2013, 04:00:47 PM »
This is where I got my AMR300 (in OZ)

http://www.adelaidejap.com.au/adeljap/carpartsavailable/turbosandsuperchargers

After 1st installing it and turning it into a vacuum pump  :-o , I turned it upside down, putting the drive on the bottom (it's driven from the left of the engine)
The only inconvenience with the setup, is that the oil filler hole is now on the bottom, and the level plug is too low, but it's filled before fitting now

It's been a steep learning curve for this forced induction novice, and if my memory is jogged, I might have the answer, if anyone gets stuck with their installation,post or PM me for help anytime.

Singles would be a pain to set up, with the enormous gap in intake draw, resulting in the problem of what to do with the unused boost in between power pulses, remembering that with a draw thru system, your plenum is a potential bomb (when BOV's go off they scare the cr#p out of you the 1st few times)
Tiny
Tiny (in OZ)
I would prefer to make horsepower, rather than buy, or hya it, regardless of the difficulties involved , as it would then be MINE

Offline Koncretekid

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Re: BSA B50 -500 APG Build
« Reply #643 on: November 20, 2013, 05:02:43 PM »

Nortonist,
Where did you get your AMR300? From what I've read about the AMR300, it produces about 300cc per revolution.  You'll need about 600cc every other revolution, or 300cc per revolution but won't get any boost at that.  So it seems you need to overdrive it, and it's a CW rotation blower, I believe, so you might want to use a jackshaft across the motor which would both reverse the drive direction and allow for overdrive.  Your installation should be similar to what I would need, so I hope you'll keep us posted. Are you planning draw thru or blow thru?

Tom

I've been looking for a while and this AMR300 showed up just up the road from me.  I'm in SoCal and the blower was in Sacramento.  I'm planning a draw thru.  If its OK with you I could post on here as anything I might post would be relevant to singles.  Just remember I'm no JimL.  I'm more in the "I tried it and it worked but don't ask for how in mathematical terms".

Give this place in Oz a shout.  They have an AMR500 for sale very reasonably.  I was going to buy it except there was a glitch on the site.  I emailed the guy and it took him a few days to get back to me.  In the time gap the 300 showed up so it should be still available.

www.sssautomotive.com.au

He seems a genuine guy and his prices are great.


[/quote]

Nortonist,
Post away!

It seems that Australia is the place to buy these things (used).  As for rebuilding them, I think Octane's postings on the build diary are enlightening!
Tom
We get too soon oldt, and too late schmart!
Life's uncertain - eat dessert first!

Offline Nortonist 592

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Re: BSA B50 -500 APG Build
« Reply #644 on: November 20, 2013, 09:00:19 PM »
Right now ts a bit like making rabbit stew.  First I have to catch the rabbit.  Hopefully the blower will be here early next week.  I'm sure there will be more question than answers.  Generatorshovel has the big question in my mind.  What to do with the unused boost between power pulses.  Initially the thought was to have a big plenum.  With a big pop off valve.  Lots of thoughts but first I have to catch the rabbit.
Get off the stove Grandad.  You're too old to be riding the range.