Machine Shop that knows Minis in/around Texas?

Started by Lone Star Mini, April 30, 2020, 01:45:04 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Lone Star Mini

Gents (& Ladies),  Little did I know when I purchased the mini I have, that the cylinder bore size is 1275 +.06 already.  I may not have to rework the cylinders, but if I must I would like to find a shop that knows Minis.  The last machine shop I took my cylinder head shaved the head, but told me they did not have any tooling small enough for the engine.  Perhaps I can find a shop locally, but thought I would check with you guys to be safe.    Thanks in advance....
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MiniDave

If you don't find one locally, send it to me - I'll get it straightened out.
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

Lone Star Mini

Quote from: MiniDave on April 30, 2020, 02:49:22 PM
If you don't find one locally, send it to me - I'll get it straightened out.

Thanks Dave..   I may take you up on that.  Do you have a shop up there or possibly do this personally?  Guessing now, but what may need to happen is to drill up to 73.5mm (1380) since they don't make 1360 pistons any longer.  Also, I will be dry decking the engine (current plans) which will require qty 2 5mm taped holes in the engine block housing along with machining a flat spot and hole in the cylinder head, etc..  You most likely know all this better than I, but that is the direction I'm heading..   
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MiniDave

#3
I have a good machine shop nearby that I take all my blocks to - however, if the block is already 60 over you can't then go the next size up - 1380's are offset bored, you can't do that to a block that's already 60 over. I would see if it can just be honed out as it is and still be usable. We'll know that after it gets micc'd for wear, taper and roundness.

Buying 60 over pistons is not an issue.

I don't think you need to dry deck the block unless you're planning to race this car, rather a modified dry deck is what you want (unless you just like the look) where you only block the water holes to the head on the first cylinder, this forces more water thru the rear of the block and head, eliminating the hot spot back there and keeping from overcooling the front cylinder. MED recommends this for street driven cars.
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

Lone Star Mini

right.. I am learning, but it just so happen I know exactly what you're talking about.  the only reason I am/was going the dry deck path was from recommendation for our typical Texas heat.  I have no interest in racing, etc..  The one element that I did not like about dry decking is the cost of the head gasket (geez)..  I'm all for the modified deck as well.  I will try to evaluate the cylinders with hopes of only having to be honed.. 
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MPlayle

As Dave says, if it is already +0.060 over then it likely cannot go larger unless it is already offset bored.

I have read about some that have been taken larger than 1380, but they were offset bored before reaching the 1380 size with the objective of supporting going larger.

Dave may know how to tell if yours is already offset bored (and by how much).


94touring

Russel may have a piston that's bigger than 60 over but doesn't require offset boring.  I'd look into that if it becomes an issue.

MiniDave

#7
Piston size isn't the issue, it's that the meat between the two middle cylinders is too small to hold a head gasket if you go any bigger than 60 over unless you offset the bores.

Dry decking the block does not make the engine run cooler, it just affects where the hot spots are - and you can accomplish the same thing for a street car by simply blocking the front cylinder's holes. The water pump is located right at the front cylinder so part of the pressure and volume go right back out the top hose and into the radiator.....blocking the front cylinder stops that and moves more of the water to the rear of the head. It also keeps the front cylinder from overcooling compared to the other three.
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

Lone Star Mini

Understood on the semi-dry decking..  I watched an MED video that explained it.  I'm just pleased I know what you guys are talking about..  6 months ago it would have all been greek.  Although this offset boring is Greek and I will simply hope that my cylinder walls only need to be honed..  in fact. . I'm going to go out now for a quick cursory look..

Thank you to all of you for your input... 
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MiniDave

A few things will make them unusable - gouges or deep scrapes, a ring ridge around the top, and a couple things you can't see like out of round or taper.
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

Lone Star Mini

Ok..  I cannot speak to 'out of round taper', but to feel all four cylinder walls, they are beautifully smooth to the touch.  Try as hard as I can, I am unable to detect any fluctuation around the full circumference and above the current position of the pistons (Red arrow area).  The only slight different felt is the seam of the blue arrow where the cylinder head stops between smooth and "rough".  Event that difference is minor.   Yet I don't feel any scrapes or gouges.  I'm hoping I don't have to do anything.. but .."
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

John Gervais

#11
Perhaps this is an option:

AEG428_1275cc Cylinder Liner|

"Will take up to a 40thou oversize piston only. These hepolite liners are 1/32" larger than the original type fitted by Rover allowing the block to have an oversize replacement fitted.Outside diameter 73.08mm.

Sold singly and 4 required as an engine set. Will need machining after fitting. "
- Pave the Bay -

Lone Star Mini

Interesting.. I wondered if sleeves/inserts were an option...
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MiniDave

#13
Costs $150/hole to have those put in and resized to match the new pistons, it would be cheaper to find another block. I have one that has never been bored......

But I would see if those bores could just be lightly honed instead. The only way to know for sure is to get it to a competent machine shop and have it measured.

Higher compression pistons in that size are available if that's what you wanted to do.

Or just ship it to me and I'll build it for you, then all you have to do is install it and drive it. It's what i do....   77.gif
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

Lone Star Mini

I have a friend that may be coming over from England to help me build my engine.  With that said, this is the reason I'm beginning to figure out what all I need parts and tools wise before he arrives next summer (2021).  This also means I must tear the gearbox and engine down to the casings to have them cleaned and worked.  This is the first of my rabbit holes after I looked at the pistons and saw "+.060" which created my first concern.

Dave, you are not terribly far so perhaps I could use your services vs a complete stranger that doesn't know the mini.  While the jury is still out, if I decide to go full dry deck or merely plug the first cylinder ports, can you do this?  What about giving the gearbox and engine housing an acid bath to thoroughly clean?  Finally, what about final tuning of the engine?  That would be a fun trip for my English friend and I to come up there perhaps.. 

Whatever I do, I have to start now and that is why I posed the first question of a recommended shop...   

Thanks all for your responses.. I have so much to learn...
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MiniDave

#15
I can do anything you need done.....I don't know about acid dipping anything, I wash the gearboxes clean in solvent, the block will get hot washed at the machine shop twice, once before it's machined, and once after.

The guy I use for dyno tuning is in Topeka, but I'm sure there's someone more local to you for that. Bound to be someone in San Antonio or worst case Dallas who can dyno tune the car I would think.

Not knowing anything about your buddy in England, I think for the best result you should let me build the motor and gearbox and you guys install and finish tuning it, but that's just my thoughts. It's not about the money but rather about consistency....
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

Lone Star Mini

Okay.. for you gents, this is basic knowledge, but I simply did not know.  Yet I'm going to share my full day of confusion and learning.  I wanted to know why a 998cc was called a 998 or a 1275 was called a 1275 engine.  I knew it had to do with volume, but that is it.  Then because I'm starting to learn about my engine, I wanted to know details...   So I started down the path of using the Volume equation:  V = (pi)(Bore squared)(stroke).  Easy right?!?   I looked through one Vizard book trying to find stock factory numbers for Bore and Stroke.. no luck.  My search on the web found the Bore for a 1275 to be 70.6mm and a stroke of 81.28mm.  Well....  these numbers did not work as I kept getting 1272cc.  I ran the numbers for 998 thinking I was doing something wrong, but no.. I got the exact result of 998cc.  After scratching my head, I reversed it knowing the volume and solved for the Bore which should be 70.66mm.. Yep,. that .06 made all the difference in the world.  To carry my confusion further, I had to figure out what units oversided pistons used (+.02, +.04, +.06, etc..).. 
- Stroke units are typically given in millimeters (& inches)
- Bore units are typically given in millimeter (& inches)
- Final engine size (998) are giving in centimeter (& inches)
But....
- all over sized dimensions (+.02, +.04, etc..) have the units of Inches

Since the final size is in metric, I simply used the metric values from the get-go...  therefore I was adding .02 mm.. nope.... I added .02 cm.. . nope..   

therefore in order to achieve the oversized 1293cc, 1310cc, etc..  I had to figure all out in inches.

Yes..  at one point I was going crazy and I scribbled loads of equations trying to get the exact numbers...  I finally got it all, but it took a while.  At least now I understand was is  meant by 1275 or 1380 or 998.. I get it.   Still so much to learn... 
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MiniDave

Yep, the size of the engine is it's cylinder swept volume - ie the bore and stroke. I've only ever worked in inches, so I'm most comfortable there - plus the engines were originally designed in inches, not mm. MM came later when the country kinda switched over to the metric system - I say kinda because they still measure distance in miles, not Kilometers, and most all of the fasteners used on any English built Mini are Imperial, not metric. But there are exceptions......

By the 90's most of the country was building everything using metric measurements, to the point that most young guys have no imperial sized tools and run into trouble trying to use their metric tools on their Minis - none of their other cars use imperial sizes so it's very confusing to them too.

On your classic Mini, stick to inches and it will all make more sense.

Unless you have an Innocenti, Authi, Australian or South African built Mini - then you're liable to encounter the odd metric fastener too!
Complete failure at retirement

1989 Cooper Racing Green
2009 Clubman S
2014 Audi Allroad

Lone Star Mini

Yep.. my last friend that visited from england when home with a suit case full of imperial sockets and wrenches (spanners).  He told me they are hard to come by now-a-days.  Well.. I did buy a tape measure with one side metric and the other imperial... 
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)

MPlayle

I went through the same formula exercise several years back.  When I looked up bore and stroke, I got a mix of inches and mm.  I also found the aspect that the oversize amount was always expressed in inches.

I solved the issue by converting to all mm.  The "quick" conversion rate is 25.4mm per inch.


tsumini

Quote from: Lone Star Mini on May 01, 2020, 06:43:24 AM
Okay.. for you gents, this is basic knowledge, but I simply did not know.  Yet I'm going to share my full day of confusion and learning.  I wanted to know why a 998cc was called a 998 or a 1275 was called a 1275 engine.  I knew it had to do with volume, but that is it.  Then because I'm starting to learn about my engine, I wanted to know details...   So I started down the path of using the Volume equation:  V = (pi)(Bore squared)(stroke).  Easy right?!?   I looked through one Vizard book trying to find stock factory numbers for Bore and Stroke.. no luck.  My search on the web found the Bore for a 1275 to be 70.6mm and a stroke of 81.28mm.  Well....  these numbers did not work as I kept getting 1272cc.  I ran the numbers for 998 thinking I was doing something wrong, but no.. I got the exact result of 998cc.  After scratching my head, I reversed it knowing the volume and solved for the Bore which should be 70.66mm.. Yep,. that .06 made all the difference in the world.  To carry my confusion further, I had to figure out what units oversided pistons used (+.02, +.04, +.06, etc..).. 
- Stroke units are typically given in millimeters (& inches)
- Bore units are typically given in millimeter (& inches)
- Final engine size (998) are giving in centimeter (& inches)
But....
- all over sized dimensions (+.02, +.04, etc..) have the units of Inches

Since the final size is in metric, I simply used the metric values from the get-go...  therefore I was adding .02 mm.. nope.... I added .02 cm.. . nope..   

therefore in order to achieve the oversized 1293cc, 1310cc, etc..  I had to figure all out in inches.

Yes..  at one point I was going crazy and I scribbled loads of equations trying to get the exact numbers...  I finally got it all, but it took a while.  At least now I understand was is  meant by 1275 or 1380 or 998.. I get it.   Still so much to learn...
At the risk of being too anal.
Just a little caution on your formula V = (pi)(Bore squared)(stroke). It works for a four cyl engine but none other

Engine volume is # cylinders times swept area of each piston
swept area is area of piston head or pi times radius squared
then
Vol= 4(pi)(1/2Bore)squared times stroke or
Vol=4(pi)(Radius of bore squared)(stroke)
Vol = 4(pi)(Radius squared)(stroke)

Also to handle oversize you do have to make to use like dimensions and also I believe the oversize is given as a diameter so that a .020 Oversize is .010 Radius oversize.

IMO fourth sigificant figure is rather irrelevant and represents no more the the tolerances of bore size and stroke


Lone Star Mini

Interesting that it only works for a 4 cyl engine..   I have not thought of this, but perhaps because most other engines do not merely go by cubic inches (Volume)..  Of course I'm not a car buff, so al I know of other engines is that they go by 6-Cylinder or V8, etc..   
Lone Star Mini
1982 Morris Mini 1000HL (heck of a lot of work ahead of me)
1992(?) Mini Cooper
1964 Austin Cooper
1980 Mini 95 (Pickup)