Milwaukee Midget

[wheelrdealer]

Chris:

Great post. Man you guys were working that motor on a long dyno pull. 

I will round up $20 and send to Jon.

BR

[manta22]

Looks & sounds great, Chris. Who knew that BMC could do something right-- if they had help.

Regards, Neil  Tucson, AZ

[Tman]

Played the audio for the office, they loved it. 

[fordboy628]

Midget,

For your permanent records.

5/30/2013 COLD leakdown test of 999cc BMC, post mega-dyno thrash:

Cylinder #           Reading            Leakage %            Source 
    1                             86/90                      4.5%                  rings/cylinders
    2                             84/90                      6.7%                  rings/cylinders
    3                             87/90                      3.4%                  rings/cylinders
    4                             86/90                      4.5%                  rings/cylinders

Given all the pulls & run time the engine has endured, AND, the fact this was a cold test, I would say it's fit und ready for "schpanking".

Some random thoughts:

1/   Leakdown % will undoubtably improve if/when checked HOT, especially across the ring/cylinder seal face.
2/   Next build MUST use a torque plate for cylinder fitting, honing, AND, ring gapping . . . . . . .
3/   Given how maxed out the cyl head has become, I am very satisfied with how well it is holding up, AND, how well it is sealing up.
4/   DO NOT, under any circumstances, allow the engine to overheat . . . . . .
 
Fordboy

[fordboy628]

Seal Team Six,

Congratulations on the success of your raid beneath the "Cheddar Curtain" last evening!!    The "Grenade" was rescued intact, and all the terrorist hamsters were "eliminated".   Congrats on a job well done!!   

Can you do anything about the carpenter ants by my deck? 

When did your team change from GM vehicles to Chrysler?

Sincerely,
Hamster Hater 

[Milwaukee Midget]

The last GM car I owned was . . .

A CORVAIR!  

Actually, two of them, 1980 - I was living in Iowa.

On the way back, I was detoured to Union Grove, got back on 94 to Beerhaven, and when I crossed the Milwaukee County line, 94 was closed and I was detoured again onto 27th street.

I left your place at 10:10 - I got home at 11:45.

Needless to say, I waited until this morning to pull the engine out of the Magnum.

Can you do anything about the carpenter ants by my deck? 
 

Can Cosmo get along with an Aardvark?

[Milwaukee Midget]

Cylinder #           Reading            Leakage %            Source 
    1                             86/90                      4.5%                  rings/cylinders
    2                             84/90                      6.7%                  rings/cylinders
    3                             87/90                      3.4%                  rings/cylinders
    4                             86/90                      4.5%                  rings/cylinders

That 6.7 is a concern, but to hell with it - I'm going racing. 

[fordboy628]

Cylinder #           Reading            Leakage %            Source 
    1                             86/90                      4.5%                  rings/cylinders
    2                             84/90                      6.7%                  rings/cylinders
    3                             87/90                      3.4%                  rings/cylinders
    4                             86/90                      4.5%                  rings/cylinders

That 6.7 is a concern, but to hell with it - I'm going racing. 

You read my mind like a Vulcan . . . . .

And besides, Mistress Helga (an authority on all things authoritarian . . . ) says:   "Hokay boyz, time fur ze schpanking . . . . . ."

Regarding travel time: Ouch!!!     Aren't the 4 seasons in Wisconsin named; prepare for winter, winter, repairs from winter damage and road construction?      Residents take heed . . .

Thanks for the "Spotted Cow"
 
Verminator

[8pack]

Why did you do the leak down test at 90 instead of 80? Was that @ tdc or did you rock it to get the highest #? Also the lower number may change due to ring rotation if you ran it and rechecked.

[fordboy628]

Why did you do the leak down test at 90 instead of 80? Was that @ tdc or did you rock it to get the highest #? Also the lower number may change due to ring rotation if you ran it and rechecked.

If I have a choice, I prefer to do leakdown tests with the engine HOT, it's just more indicative of the engine's running condition.    But, sometimes the only time available to test is after the engine is off the dyno, cooled down, etc, etc, and some numbers, even if cold, are better than none.

I usually like to test with 100 psi input pressure, it makes the % calculation easy.    But my compressor at home is on its' last legs & I can't get 100 psi out of it.   I just use 90 psi input and do the math.

Normal procedure is to rotate the engine in the correct direction up to TDC of the cylinder being tested, fit the pressure adaptor and have at it, take the reading.   If I encounter a low hole, I usually rotate the engine a few rotations & retest.    Consistent low tests are low tests, end of story.

On a situation like this, one low(er) hole with all cylinders tested cold, Midget should probably retest all cylinders hot after the engine is back in the chassis.   I would expect the hot numbers on this engine to be 1% or so better, the weakest hole might change with a hot test.    Since there is no indication of a potential, dramatic problem at this point, the ambition to put more time and effort into this is waning like the current moon phase.    For those of you who do not know, Midget is up against his busy time of year; 6 days a week or more, ? hours a day, for several weeks in a row.    It really cuts into car prep, er, drinking time . . . . . .

Given the amount of thrash time the engine has seen, the fact it was honed without a deck plate, rings gapped without a deck plate, etc, the readings are really pretty good.   I think everybody would have liked to have had better, lower readings, but it is what it is at this point.    Time to take it out and see how fast the little grenade can go . . . .
 
Fordboy

[fordboy628]

How to Modify your Weber Carburetor properly  OR

Weber Carburetor Porn!!!!  OR

How to turn your expensive Italian/Spanish engine bit into an undriveable piece of crap . . . .   Part six . . . .   (yes, this will be a multi-step tutorial . . . .)

Midget,

More info for your permanent records, re: Carb setup post dyno.

Weber 45DCOE Type 152   New Spanish Mfg'd with steel throttle shaft
Main jets                      185
Air jets                         190
Emulsion tubes              F11
Idle jets                        60F6
Starter jets                    85F9
Starter air jets               150
Pump discharge jets       55
Pump bleedback jet        00
Pump stroke                  8.1mm
Needle & seat                250
Float settings                 8.5mm & 15mm
Idle mixture screws        2 turns out
Idle air balance screws   closed
Main venturis                 40mm modified, 40.2mm net ID
Aux venturis                  4.5 modified
Throttle shaft screws      modified, MB design
Throttle blade angle        90 degrees @ WOT
Throttle speed screw       Adjust for best acceptable idle speed.   2500 rpm minimum for full race engines.
Air inlet horns                48DCOE surface mount, shortened to 28mm O/A length, 48mm ID

This carb flows 270 cfm/barrel @ 28" test pressure, as setup.

For anybody building a BMC 1000/970/1070, if you are using a Weber, and it flows this much air, the above settings would be a good starting point for your testing.
Happy tuning/testing.
 
Fordboy

[Geo]

Chris, Fordboy, and crew,

I have been in awe at how this turned out for the past 70 pages. From broken to badass with a fantastic amount of information. For a few days I have searched for the words, however there are none that come to me to express my admiration for applying science to extract power from a limited design. Great job boys! Lots of hours in this and I appreciate your sharing it! I'm looking forward to the engine install, the show coming up, the race prep, the tow out and the run.

 

Geo

[Milwaukee Midget]

Geoff, THANK YOU.

This is from post # 3 of this saga –

I'm destroking a 1275, which will get me the bigger valves and less shrouding.

I know I have an uphill battle with the 5 port head, and I suspect valve overlap on a short stroke Austin engine is going to be key to getting it right, plus maintaining a high compression ratio. 

I am struggling for good advice on an undersquare A-series engine.  Most information out there deals with stock stroke lengths, and almost all of the racing engine development assumes an oversquare configuration.

So I guess I'm building the world's tightest winding tractor motor.

I’ve also stated that I am at best a shade tree mechanic.  I’ve learned a lot, and my gratitude to Fordboy goes beyond words.  Not only have I found a resource for an eccentric engine build, I have made a very fine friend.  His insight and expertise has been KEY, CRUCIAL, CRITICAL to getting this thing where it is today, but that pales to just tipping back a beer on the porch with him and laughing our asses off.


And I simply cannot ignore the input from the rest of you who have chimed in, be it to warn me off, redirect my thoughts, or call me foolish.  It’s not all expertise and chops – it’s wisdom and patience I’ve learned from participants on this forum.

I’m often saddened by those who start and for whatever reason can’t follow through on their builds.  5 years ago today, I bought the Midget.  Given my past history with projects of this magnitude, it could have very easily remained the dust covered, disassembled pipe dream that it had become for the former owner.  I can easily see where someone could lose interest and focus.  But this forum and the shared contributions of all of you have made the difference between the Midget being an oversized, oddly shaped garden hose storage unit and a credible race car.

These forums have all been inspirational for me.  I simply hope I'm giving as good as I've gotten.

To the brain trust that is landracing.com      

[salt27]

Trust me, we have all enjoyed this.

  Don

[fordboy628]

Geoff, THANK YOU.

This is from post # 3 of this saga –

I'm destroking a 1275, which will get me the bigger valves and less shrouding.

I know I have an uphill battle with the 5 port head, and I suspect valve overlap on a short stroke Austin engine is going to be key to getting it right, plus maintaining a high compression ratio.  

I am struggling for good advice on an undersquare A-series engine.  Most information out there deals with stock stroke lengths, and almost all of the racing engine development assumes an oversquare configuration.

So I guess I'm building the world's tightest winding tractor motor.

I’ve also stated that I am at best a shade tree mechanic.  I’ve learned a lot, and my gratitude to Fordboy goes beyond words.  Not only have I found a resource for an eccentric engine build, I have made a very fine friend.  His insight and expertise has been KEY, CRUCIAL, CRITICAL to getting this thing where it is today, but that pales to just tipping back a beer on the porch with him and laughing our asses off.


And I simply cannot ignore the input from the rest of you who have chimed in, be it to warn me off, redirect my thoughts, or call me foolish.  It’s not all expertise and chops – it’s wisdom and patience I’ve learned from participants on this forum.

I’m often saddened by those who start and for whatever reason can’t follow through on their builds.  5 years ago today, I bought the Midget.  Given my past history with projects of this magnitude, it could have very easily remained the dust covered, disassembled pipe dream that it had become for the former owner.  I can easily see where someone could lose interest and focus.  But this forum and the shared contributions of all of you have made the difference between the Midget being an oversized, oddly shaped garden hose storage unit and a credible race car.

These forums have all been inspirational for me.  I simply hope I'm giving as good as I've gotten.

To the brain trust that is landracing.com      

Gosh, golly, gee,  thank you for the praise, I'm not sure how much it's deserved, but I'll take it.   But know this, everybody in racing who becomes proficient at it, has had some help at one time or another.    I am indebted to the likes of Harold Bettes, Jim McFarland, Dema Elgin and countless others who pointed me in the right direction in my youth.    Since I cannot repay that debt, I try to pay it forward by extending help to those now in line behind me . . . . . . . .

Little payment as such, but a better payback than most in the industry give back to those who wish to enlighten themselves . . . . . . . .

And as you mentioned, there are countless others out there in the blogosphere ready to chime in, however they can help, whenever they can help.

I too have found a new friend who shares my enthusiasm for all things made from barley.    And I'm softening my outlook about cheese products . . . . . . .
 
Fordboy