Milwaukee Midget

[Stainless1]

throw another log on the fire and put the whip to the damn squirrels Stan... I barely have internet out in the sticks, and my old stuff gets me there... 

[fordboy628]

midget,


As per my K build notebook,   Aka:  Dunning-Kruger Resource Service

Bore:     75.5 mm    (2.973")
Stroke:  55.5 mm    (2.185")

Results in:   993.88 cc displacement

I added the US based inch sizing for those who do NOT speak Metric: SuperFlow, etc, among others.   Included, but also not limited to:  Goldfish/Vikingboy   Take your pick.


Where is timing now?   Suspect it needs more than what is in it.     Although, need to get the fuel curve sorted first.

 

Mr. (formerly Captain) Obvious

[fordboy628]

midget,


OK, panic over, found my Milwaukee Midget BMC/Rover Build shop notebook.

Has the "enlightenment" you seek.

Funny thing . . . . turned up in the last place I looked! ! !


 

[Milwaukee Midget]

Earlier in the "Dynothon" thread, I commented that i felt as though I was "tripping on the risers heading up a downward escalator."

Well, I definitely skinned my shins on it this morning.

I was running a compression check. I had the spark plugs out in order to save the battery and wear-n-tear on the starter.

Now normally when I have the plugs out, I put the boots back in place in order to prevent anything from falling into the cylinders.

I started with the "1" hole, and then jumped to the "4", the "3" and lastly the "2".

I had nothing in my hand except the compression checker. 

compcheck by Chris Conrad

Note the arrow pointing to the plastic/rubber button extender for the Schrader valve. After checking # "2", I went to relieve the pressure and noticed that it was missing.

gauge by Chris Conrad

Nope - wasn't on the floor - wasn't in the catch basin under the motor - wasn't inconveniently lodged in the nest of wires that are the EFI/Ignition bundles.

No - it was wedged between the exhaust valve and the seat of the 2nd exhaust valve in the "1" hole - further compressed and wedged by the piston crashing into it.

pos by Chris Conrad

With the artistry and acumen of a dentist and an accompanying dental hygienist, Mark was able to fish it out through the exhaust while I was able to blow compressed air through the sparkplug hole.

A cylinder that was giving us ~200 psi was now barely giving us 150. A double check of the lash indicated a bent valve.

Fortunately, when Mark did the flow work on the head, lo these many moons ago, he kept a spare set of valves in reserve.

head by Chris Conrad

The head is off.

There's simply nobody to blame but myself. I KNOW BETTER than to leave holes open like that. I got in a hurry to start tweaking up the dyno numbers, and that turned around and bit me solidly in the toush.

I've always shared the good, the bad, and the ugly on this build. Both successes and problems have been witnessed here, and being a human project, one should accept human-related downfalls.

I've usually been able to forgive myself on the stupid stuff - but this one has just about taken it all out of me. 

Let's see how it comes back together. Can't do anything until Monday, anyway. I'll keep everyone posted.

[WOODY@DDLLC]

Progress in spite of your efforts! 

[Dr Goggles]

Aw man,  I winced when I saw that, fingers crossed for you this week.

[Milwaukee Midget]

From the Dynothon thread -

Welcome to Mark's little corner of Koozebane.
20210614_180420 by Chris Conrad, on Flickr

20210614_085721_Burst01 by Chris Conrad, on Flickr

It's positive that I know there are two basic personality types in the Dunning-Krueger effect, but just when I thought I had my place on the spectrum plotted, something stupid happens, and I need to reevaluate my position.

After pulling the violated exhaust valve and replacing it, we returned to checking lash on the cam buckets.  Exhaust is supposed to be .010, and going through the lobes we're good until we hit the 3 cylinder, second valve.

.017??!!??!!

I have NO IDEA WHERE THIS CAME FROM, but lodged between the valve and the seat was a small piece of very stiff wire, possibly from a wire brush?

One on one, with friends and colleagues, I'm not above making crude comments. I do make every attempt to read the room before I say something vulgar, and while I've been cuffed in the ear by Kate on a few occasions for speaking my mind, I genuinely try to not air such thoughts in public forums such as this.

But given my level of frustration, I am compelled to proffer this thought in the form of a question which I will not voice an answer to:

What does this thing left of the penny look like to you?

20210614_201900 by Chris Conrad, on Flickr

IT was easily accessible from the exhaust port - Mark grabbed it with a pair of needle nose plyers, and I gave the tappet a quick wrap with a socket and a rubber hammer. AGAIN, we checked for leakdown and were at ~ 2%. For a freshly reattached head on a cold engine with about an hour of break-in time, that's great.

Back to it tomorrow.

[fordboy628]

Welcome to Mark's little corner of Koozebane.
20210614_180420 by Chris Conrad, on Flickr

All I can see is a tired, old guy, at the end of his run, just a few days from another decade, fading into the background of a photo.   Wish it were not so . . . . but it is.      Turns out Thomas Wolfe was right after all . . . . .


"No man ever steps in the same river twice, for it's not the same river and he's not the same man."   Heraclitus

[Milwaukee Midget]

From the Dynothon Thread -

Dynothonresults by Chris Conrad, on Flickr

114.5 hp . . . at 9,500 RPM.

9,500 rpm is where the dyno stopped moving water.

Essentially, we turned a SuperFlow 902 into a Waring Blender.

We're thinking it's a 125 hp engine, but the dyno simply isn't capable of providing water at this RPM and providing reliable results.

Here's a printout of our last few reliable pulls -

Finalpulls by Chris Conrad, on Flickr

I'll point out a few things here - at least as I understand them. I'm certain Mark will join in when his ears stop ringing.

Note the torque curve - it hovers between 63 and 67 ft lbs from 6,300 to 9,500 rpm, and was showing no indications of rolling off any time soon.

Horsepower, of course, is a function of torque and revs - and as long as the torque remains constant or doesn't fall off, as the revs climb, so does the hp.

So what does this mean for our attempt this year?  Well, let's look at what's worked in the past. Mark superimposed the Grenade graph onto the K graph -

GrenadevsKseries by Chris Conrad, on Flickr

We tested in a much narrower range with the old A-Series, and it gave a LOT more torque below 7,000 AND better power numbers - UNTIL 7,800 RPM. That's where air flow and electronic fuel injection start to really show their mettle.

We set the rev limiter at 10,000. It appears that the way we'll need to drive this thing is to just simply wring it out in the lower gears and hope 4th doesn't drop us below what the A-series gave us - the 3-4 is right there in that pocket where the two engines power curves cross.

THANK YOU FOR LETTING US SHARE THIS - it was both frustrating and fun, gut-wrenching and stress relieving.

[wheelrdealer]

Just sent my $57.25 (.50 X 114.5) to Mr. Slim.

Thanks Chris for sharing this top secret skunk works data with this mere mortal small block chevy guy. I don't get to see data like this often. 

BR

[Rex Schimmer]

Chris,
Did you have an O2 sensor in the exhaust? Without having a BSFC reading from the dyno how did you figure out how close you were on air/fuel ratio? Looking at the hp curves it sure looks like you need to RPM it to make some good power. What do you think the max RPM limit is? Didn't  you turn the "grenade" 10,000 and that was with a three bearing crank, I would think that this motor should see 11,500 to 12,000 easy.

Rex

[jacksoni]

I just sent my contribution, bumped up a bit from the pledge.
Chris, I have some concern about your gears and what you may have available. As Rex is suggesting, 10k is not going to cut it for peak power doesn't look like and dropping off the peak on shifts may put you in that slight soft spot in the curve. (my 4 stroke engine, also destroked as yours, had a big hole right where it landed on shifts, not fixed until I got a trans with adjustable ratios to get, in my case, the 4-5 shift very close. ) Rough calculating you are going to need a rear gear in the 5-1 range with a 22" tire to go 125-130 at power peak range. I see no reason that more rpm can't be done safely with the small valve DOHC (springs??) and the short stroke. Piston speed will still be reasonable. What have you got?

[Milwaukee Midget]

Rex, Jack, we are thinking along the same lines.

We're currently running 4.22s. 4.55s are an option - I'd need to source a set.

The engine is likely not the issue. I'm more concerned about the driveshaft - and possibly the transmission.

Yes, Rex, we essentially built a Hyabusa in an MG block. We were able to log in the Holley HP system with the O2 sensor. It controls both spark and injection.

We're running Alpha-N - we've got no data points from MAF, MAP or ambient temp, but we were able to tune with TPS, water temp and O2 inputs.

The system can create really elaborate logs, and these logs can be brought into the overall tune to make adjustments in closed loop. When you've reached the point where superimposing the learn table into the function creates no change, then you've arrived. Here is a typical "learn table" for fuel adjustment -

Learntable by Chris Conrad, on Flickr

Going back and forth, we were able to enter and/or develop a target grid for fuel requirements -

Target AF Ratio 6.15.21 by Chris Conrad, on Flickr

This is what it looked like when we were done -

Fuel Graph 6.15.21 by Chris Conrad, on Flickr

After we got the fuel table established, we tried putting in and taking out cam timing. I need to go back to my notes, but I want to say we wound up tightening the lobe center either 4 or 6 degrees.

Then we took on the ignition timing. Above 35, power started falling off, and below that, it really didn't make any difference, so we just dialed it all in at 35 and it runs and idles great.

Spark6.15.21 by Chris Conrad, on Flickr

So now that we've got the tune in place, the O2 sensor will be what we'll be leaning on to make adjustments to the fuel in real time at Bonneville.

Provided I don't screw something up, the tune is on the hard drive, and we're good to go!

[WOODY@DDLLC]

Chris, just keep your compression tester away from the computer! 
Good job so far youse two!!! 

[Stan Back]

You might consider getting a push off to about a 100 MPH to at least the one.  And then use the two gears that are the closest together with an appropriate rear gear.  Just a thought, probably not a good one.