Milwaukee Midget

[Milwaukee Midget]

Well, this was the unit I was looking at, modifying it to fit where the alternator lives at the moment -



I guess I don't see where there wouldn't be room once the alternator is ditched.

I could see where the Moroso unit might have a tough time keeping up with a full-tilt small block, but I'm already running a 1500 radiator and an auxiliary radiator off of the back of the head, 2 gallons of water, it's 1000 cc's, and I had no cooling issues at Maxton or on the dyno.

The Jabsco appears to be a fairly heavy duty unit.  I suppose I could pull the impeller and weld up the bearing boss on the existing pump, or get a plate with fittings.

Not arguing, Don, just asking and wondering.

Trent, if it's the replacement PUMP you and Mike are talking about, the ones we've all seen available through Speedway or Summit, I could see Mike's point.  But the only thing I'm looking to change is the way the existing pump is driven.

Thanks, guys.

[fordboy628]

Guys,

The only real issue on ANY PUMP OF ANY TYPE (oil, water, air, etc...) IS:  Can the pump provide the required flow at the pressure required or available.  The answer here is: of course there is a pump out there that can adequately cool a 1000cc race engine.  The next question in the natural progression of engineering this is: How practical or difficult will the conversion become?  I have used a Jabsco "Water Puppy" as a circulation pump in a dyno installation as part of a preheating/post cooling system.  I do not know the flow/pressure #'s off the top of my head, but my specific concern is that the flow & pressure of the water puppy are probably too little to "effectively" cool this BMC.  What is not generally know or accepted about BMC's is that there are "hot spots" in the cylinder head that demand adequate water flow & PRESSURE to prevent localized boiling in the cylinder head.  Localized boiling is the fastest way I know of dial a bunch of power off or crack the head.  Some of the required cooling system mods (such as the aux. heat exchanger & line) are already in place, so Midget is already ahead of the game there.

If you want "FREE" horsepower (as if anything is "FREE")
1]  ditch the alternator, IF, a large enough battery can be legally fitted.  The only worries would be:
     A] adequate cold cranking amps for starting, (use a jumper battery)
     B] adequate amperage available to run the computerized ignition.  A battery to perform the latter function need not be too large or heavy.
     C] I estimate that losing the alternator should gain 3/4 hp @ high rpm.
2]  drive a modified stock water pump with a gilmer belt drive at a reduced rpm rate.  No idler/tensioner just a two pulley toothed belt setup.   Although a v-belt
     could be used with the stock pulley and damper, this does not reduce water pump rpm and would not gain any hp there.
     A] I have good dyno experience that reducing the water pump rpm can gain 1/2 hp @ 9000rpm.

Anything to simplify the vehicle, reduce it's weight, reduce it's drag, reduce it's frontal area or add horsepower is of benefit to the quest for top end speed.  Remember:  top speed is a function of the cube of horsepower available..................

I'm thinking that this is the easiest way to gain hp while retaining reliability, and I freely admit to being a card carrying member of the "KISS" Engineers Club.   (Please, NO WANKER COMMENTS ABOUT THE BAND "KISS"!!!   Gene Simmons did not make my list of top 20 Bass players of all time, although I would put him somewhere in the top 100, just for his tongue.)

I've got a selection of gilmer belt components available, but I have no idea whether anything is suitable.   Another reason to make a pilgramage to "Beerhaven".

Got sidetracked from the Weber list with this, sorry.   

 
Fordboy

[Milwaukee Midget]

Trent, upon further review - I'm seeing Mr. Lefevers point.

The Moroso motor turns 2600 RPM, and that's it.  Just eyeballing the kit, it looks like we have about a 6:1 drive, whereas the drive pulley is larger on the Midget than the pump pulley - probably a 1:1.5/2 ratio stock.  The references earlier mentioned 2000 RPM engine speed for optimum cooling, so clearly this kit is taking me in the wrong direction.

Fordboy - extra batteries are legal, and weight is desirable on the salt - any excuse to bolt in an extra 60 lbs of lead low in the chassis, I'm there. 

[Tman]

I came to the same conclusion after talking to Mike. I am going with stock style pump belt driven.

[38flattie]

Chris, I have both of these water pumps-either will suit your needs, although the Stewart is the far better pump!

http://www.prpracingproducts.com/products/16_Remote+Mounted+Electric+Water+Pumps.html?phot_key=19

http://www.stewartcomponents.net/Merchant2/merchant.mvc?Screen=PROD&Product_Code=E558A&Category_Code=ElectPump

[fordboy628]

Midget,

My recollection is the stock belt pulley setup is an over drive ratio on the water pump.  Do not know exact ratio, but damper pulley dia divided by w/pump pulley dia gives you the ratio, probably 1.4 to 1 or so.    Need to go to about a 3/2 to 1 UNDER drive.  Not sure if there is room for that..........

Designing a gilmer belt drive for XSPs & 1275s was a project I left unfinished when I left PHP...........

When are you available for me to drive up and check out your project?   

Fordboy

[fordboy628]

Tiatan Motorsport UK manufactures the following:

 This kit contains the following items:

 E0892314602SK - Mini 1.13:1 Water Pump Drive Kit, comprising:- 

E0892314600A3 32T L Steel Crank Pulley 1   
E0892324800A2 36T Alloy Water Pump Pulley 1   
DBW27005001A4 270L050 Belt 1   

Don't know if this precludes use of the damper.   I have some 44T alloy titan pulleys for .625" shaft dia.  Will check to see if this is workable.

How is crank trigger mounted??   Trick here is not to create a "cascading nightmare" of changes to existing setup.   

Fordboy


 
 

 

[Milwaukee Midget]

Where's my Ritalin?

How is crank trigger mounted??   Trick here is not to create a "cascading nightmare" of changes to existing setup.    

Fordboy

We're on the same page.

Okay, guys – Horse first, THEN cart.

Udo Horn reminded me of this one fact.  “Every bolt has to be turned by someone”.  So for the time being, my goal is to reassemble, dial in and maximize the combination I have with the parts available.  I’m looking at dyno day being April 21 to do that.  Deadlines are helpful to me.

The reason I was looking at the Moroso was for the sheer ease of install.  Pull alternator, install motor, wire, switch, done. My thought was that for $100, I free up a pony or two, and maybe pull the vibration dampener.  Now that I’ve figured out that this idea won’t work, my inclination is to maintain my original position – which I know works.  

For the moment, I’ve got to take re-engineering and re-routing the cooling system off of the table.

[Tman]

If/when you do get to that point Chris remember that I am now a dealer for many of those various electric pumps

[Jack Gifford]

... Remember:  top speed is a function of the cube of horsepower available...

Umm... that's backwards. "cube root" in place of "cube" would make it less-wrong. Most readers probably knew what you meant to say, though.

EDIT: Actually, I guess I don't know why you wanted to point out this relationship when trying to justify tiny power increases. For example, a one percent power increase could result in a speed gain of only slightly less than one-third of a percent.

[fordboy628]

Hi Jack,

Yes, you are correct.  Mea culpa, guilty of trying to simplify.  The point I was trying to make is: The Midget will need every Hp that can be wrung out from 1000cc's.  My experience with BMC XSP F/Jr's (1.0L & 1.1L) & 1275's is that well tuned combinations make 95/100 brake hp/litre @ the flywheel, when running a 9000rpm rev limit.  And therefore they need all the help with ancillaries that can be devised.  I would like nothing better than to see this one make 105bhp/litre.   

Best regards,
Fordboy

[fordboy628]

Hi Midget, et all,

I am not suggesting that all of the following are required or necessary, just that this is what I have available for your possible use, @ no cost.  (Well, the cost of the beer.)

Care package list of Weber Parts I have gathered for your possible use:

Main jets:   185-175-165-155-150-140
Air corrector:  185-190-195-200-205-210
Emulsion tubes:   F6-F11-F16
Accelerator pump jets:   35-40-50
Accelerator pump exhaust jets:  variety from .00 to 1.00
Idle jets:   variety
Needle & seat:   200-225-250  (what is in carb now is probably OK if at least a 200)
Chokes:  40mm-42mm-43mm
Venturis:  std. 4.5's - modifed 5.0's - #69904.450  (what is in carb now is probably OK)
Air Horns:  pair of 48DCOE's shortened to 1.12" length
and some alternate softmounts

Was trying to fill in the holes of what you listed that you had, so that you would have any & everything at your fingertips when on the dyno.

I think your starting point should be:  Find out carb installed angle; 8mm float height or adjusted for mounting angle; 38mm choke; F2; 165 main; 180air; 200 needle & seat.   And leave everything else as is, at least until I can get a look @ the carb.   
 
Fordboy

[fordboy628]

Midget,

Block, damper and water pump are std BMC 1275?

Fordboy       

[Milwaukee Midget]

Midget,

Block, damper and water pump are std BMC 1275?

Fordboy       

Affirmative on all three - I appreciate the mock up you're doing.

A couple of pics of the crank trigger bracketing - front, in place, radiator out -



Very close clearance on the belt passing through (yes, though) the standoffs coming down from the alternator - yet another reason to lose it -



Cam card -



I appreciate the help - more than I can say. 
 

[fordboy628]

Midget, et all,

As per other offline conversation, MY valve spring pressure thoughts are based on old records from BMC 1275 SCCA race engines running: .50" lift & 1.5/1 roller rocker ratios, although Titan roller rockers, using cams with "softer" NEGATIVE accelerations.

90# seat; 250# open    when running 6000/8200 rpm range
95# seat; 270# open    when running 6500/8500 rpm range

To CALCULATE the minimum valve spring pressure required for a given rpm; we need to know moment of inertia of the roller rockers; weight, in grams, of all moving components including tappets, and a cam profile with displacement, velocity and accelerations.  Such as Cam Pro, etc., electronic profile.  Just calculating the spring requirements, however, does not gaurantee that a valve spring exists that will fit in the space available AND have the spring rate required.

This is an ongoing issue with smaller engines in general, not just BMC's.  Cam manufacturers focus on Chevy/Ford/Dodge and let's face it, they pay more attention to flatheads than BMC's........   

Personally, I would just go up to the higher spring pressures as you are committed to the higher revs.  My past experience, as we discussed, is that the spring pressures being used are simply inadequate for the forces being encountered at the rpm's being run.
 
MB