Milwaukee Midget

[tauruck]

Chris, what's wrong with Lucas?.

[Interested Observer]

MM,
In reference to the ARP stud loading, some concern may be alleviated by referring to page 337 reply 5053, which came about subsequent to the one which you re-discovered and became worried about.  In the reply the generated load is shown to be comparable to the Rover schemes. 
Your inquiry to ARP is interesting.  They make it sound all very professional and that may well be, but I completely agree with your assessment of their stated development process.  Maybe I should go over there and offer to take their guinea pig K off their hands!

[Milwaukee Midget]

Maybe I should go over there and offer to take their guinea pig K off their hands!

Keep calm and CARRY SPARES. 

It did have the smell of a canned response, but we kind of knew from the get-go we were heading into uncharted territory with this one.

Chris, what's wrong with Lucas?.

Nothing, really - the breaking yards of virtually ALL countries with ties to Great Britain are filled with all kinds of spare Lucas components . . . some may still actually work . . . 

[fordboy628]

I know you can be too big with carbs, but I didn't think you could be too big with TB's.... I always thought you wanted to get the largest charge of A/F the motor would pull in and always thought that was done with the least restriction.
I know.... YMMV 

Yes, the least restriction is usually best, but it can and does drive up the rpm range.    One of the issues with this build-up is the wide power band requirement.   One of the keys to producing exceptional torque is going to be engineering the correct gas speed (velocity) in the intake tract Vs displacement and flow demand.    If we can produce excellent to exceptional torque, in the desired rpm range, everything else falls into place.    The goal for the operating range is: 6500 rpm to 9000 rpm, maybe 9500 rpm max.

If the intake tract is too large and the gas speed is too low, the project becomes a high winding, high rpm "screamer".    Kinda like some of the performance motorcycle engines.              Usually not the best situation with only a 4 speed transmission.

I'm off to my weekly day @ "drag city".

 
Fordboy

[fordboy628]

Maybe I should go over there and offer to take their guinea pig K off their hands!

Keep calm and CARRY SPARES. 

It did have the smell of a canned response, but we kind of knew from the get-go we were heading into uncharted territory with this one.

midget, IO,

The more this is theorized and kicked around, the more convinced I am that the only way to resolve this is to test the theories by applying load in increments, and measuring any resulting distortion in the assembled parts.

I feel pretty certain that we can find some "comfortable" spot where clamp load is increased (?, maybe more reliable?) over the stock torque to yield bolt, and any induced distortion can be "re-machined out" or handled with additional clearance or whatever.     This is going to be one of those engine types that I suspect will require "non-conventional" methods to gain reliability, ala Renault R16.

So what else is new?    At least it has the right number of ports and valves . . . . . . .   unlike a   

 
GladI'mintheeightiesboy

[fredvance]

We, me, Larry Forstall and his group, have tried bigger throttle bodies on a variety of Busa motors. The only motors tha bigger TBs have worked on were big, 1635&1700cc, motors with the latest Carpenter, big valve , head. And not all of those have responded well. I tried a set on my 1657cc, 15-1 compression motor and lost HP.

[jacksoni]

I think our resident guru (Fordboy) previously suggested that airspeed may trump CFM. Is a balance though as in all thinks.

[fordboy628]

We, me, Larry Forstall and his group, have tried bigger throttle bodies on a variety of Busa motors. The only motors tha bigger TBs have worked on were big, 1635&1700cc, motors with the latest Carpenter, big valve , head. And not all of those have responded well. I tried a set on my 1657cc, 15-1 compression motor and lost HP.

Yep, I'm not surprised.

A long time ago, in a galaxy far, far away, when I owned PHP R/E, many of my customers were convinced that bigger carbs were the solution to their "lap time woes".   The dyno, typically, disagreed with them, much to their chagrin.    It was usually a very expensive "experiment" for them.    And don't get me started about "driveability" under acceleration, where a big "bog" from oversize carbs kills you "coming off the corners" . . . . . . . .

IF, as you point out Fred, valves, ports, displacement, carbs or T/B's, et all are enlarged, appropriately, there may be a useful gain.   It is the "combination" of the components that provides the result.     Working with some of the older road race standard engines, such as Cosworths and Harts, I was able to squeeze out some "useful" gains, on the order of 8%-12% without any longevity penalties.      It was a matter of being thorough and rubbing some science and engineering on it.    "It's complicated."    I think I might have shared that thought before . . . . . . .

Now that I'm older, (and I'd like to think smarter,  . . . . ahhh, well, . . . . smart-assier) you not only have to argue with whatever dyno or flow bench I'm using, but then you have to argue with my laptop, all before you even get to argue with me.     I'm able to stay remarkably disengaged using this strategy.    Just ask db.

And so this is the perfect reason to spend some extra time on some modeling, simulations and flow work, before there is any start to: "cutting parts".     Guess I better get on the stick.

 
Fordboy

[fordboy628]

midget,

Throttle bodies arrived yesterday at the ranch, in a gasoline soaked carton . . . . . . . .   

I'll let you know how they look later in the day.

 
Fordboy

[fordboy628]

midget,

I know you have been busier than a dog who is trying to decide where to lick himself,      but, where are we on a schedule to do the trial fit up of the mating of the 'K' into its' new home?

I know this weekend is out because of the holiday, but maybe you can look ahead on your schedule and give me some time to plan to be there to help out?   Or at least misplace the thermostat?     Drink your beer?     Etc?

 
Fordboy

[fordboy628]

BTW,

Have just finished the MGB flow bench slider.    Will begin to accumulate MGB cylinder head flow data sometime in the next 2 weeks.    Might learn something useful for your "in the future" MGB + huffer rebuild.

Willing to work for: beer . . . . . . . .

 
Somethingdarkandmaltyboy

[fordboy628]

midget,

OK, got the T/B's unboxed and they look OK, only one arm bent from shipping.   Some specifics:

A/    Delivery end 38mm Ø opening
2/    Throttle blade 40mm Ø,  this is probably OK.
d/    Center spacing between 2/3   88mm or so.  That's good.
e/    Ends spacing 1/2 and 3/4       76mm now, but this is adjustable.
f/     the twin injector bosses are at different angles, probably a good thing
g/    there is a provision for a throttle position sensor
h/    it looks like all the throttle blade adjusters are Weber carb parts, that's a good thing
i/     OD of the upstream end is 2.148" Ø, but with a large ID taper to 40 mm (?)
k/    injector positions are downstream of the throttle blades . . . . .
l/     they are very short, so that gives lots of options for manifolds and air horns . . . . .
m/   they are heavy
 

Probably can make them work, depending on how they flow.    Might be able to "help" the flow a bit with the same type of mods I do to Webers, at least around the throttle blade.   Keep in mind that injector position can really help or hurt bhp.

And it is important to note that whoever assembled these has the adjusters between T/B's installed backwards, against the spring, instead of the adjustment screw, thereby un-synchronizing the throttles as they are rotated open.    Very clever.

I'll fab up a flow bench adaptor next week.    Send in the clowns, er, Send down the injectors.

What were these supposed to fit?    Are there any air horns or such to fit?   Etc?   Etc?

 
Fordboy

[Speed Limit 1000]

midget,

What were these supposed to fit?    Are there any air horns or such to fit?   Etc?   Etc?

 
Fordboy

Z1 900, KZ1000, GPZ 1100 and GS1100 Suzuki's. Should be able to find stuff on fleabay.

[Milwaukee Midget]

Z1 900, KZ1000, GPZ 1100 and GS1100 Suzuki's. Should be able to find stuff on fleabay.

Corectomundo, birthday boy.

Just talked with Mark - looks like the butterflies are Weber pieces.  He'll be receiving the injectors today, so we'll know if they're properly sized, or at least serve as plugs for the flow bench testing.

[Speed Limit 1000]

I have 4 1980 G1 Kaws and a '82 1100 GPZ  with factory FI