New guy with Classic Mini

[Xist]

I will watch that one. I enjoyed this video!

https://www.youtube.com/watch?v=hpb2Him9CUo

It is not a Mini, but I hope they gave them the same treatment!

[Varn]

My first car was a Mk3 sprite 1098 in 1969. Got 30 mpg driving as hard as I could. Always liked the Mini's.

Gas was 20-30 cents per gallon.

[ALS]

My brother just restored a 1969. He yanked the anemic Mini motor and dropped in a Honda V-Tech. Lets just say according to him the car is a real handful with liberal use of the go pedal.

I never asked him what the gas mileage is but it has to be pretty good considering the car weighs less than 1500 lbs.

[Bicycle Bob]

Whoever put that carb on it was not interested in mileage. I'd check to see if it has a hot cam to go with it. You can buy that engine down to 850cc for the economy versions, and it isn't too comfy internally when over 1100.
You probably want to get rid of the fender flares. Unfortunately, the easiest solution for streamlining is an Ogle body, and they are a bit thin on the ground now. Rounding the front, reducing the intake and de-seaming the A pillars would help. Going to a 1-box shape with a more raked windshield might halve the cd.

[duncan]

Throw the Weber over a hedge and fit a decent single SU - a 1 and3/4 inch would do fine
don't mess about with twins!

As far as fuel efficiency is concerned the old 1275 A series is an incredibly efficient unit, I don't think any of the modern engines get anywhere near the same thermal efficiency so replacing it with a Honda will give more power but worse MPG

The biggest efficiency improvement would be a higher final drive - mini's used to have a 3.44:1 final drive but you could buy a 2.9:1 - that makes a BIG difference to mpg

Three decades ago I had a 1275 bored and stroked to 1425cc in a mini with a soft top - that was a fun car!

[some_other_dave]

Originally Posted by ALS

My brother just restored a 1969. He yanked the anemic Mini motor and dropped in a Honda V-Tech.

Sorry, you just hit one of my pet peeves: VTEC is Honda's "pick a cam on the fly" technology. V-Tech is a crappy phone.

I believe that you either have to put very wide fender flares on the Mini to fit a Honda B-series drivetrain, or you have to slide the car in half lengthwise to make the whole thing wider.

-soD

[Varn]

Hi ALS
I bet the Honda engine really worked good on the Sprite. Thanks for sharing. The longitudinal engine worked well. Especially replacing a 48 hp turd. I would like to find a nice sports car to mount my 1.6 diesel in.

I really don't believe that 1950's designed 4 banger was "that" efficient.

[duncan]

I really don't believe that 1950's designed 4 banger was "that" efficient.

The hand of God was on that design!

Very thermally efficient - very good at converting the heat into power,

modern engines are much much more efficient at producing more power - but a lot of the techniques to get more power actually reduce the thermal efficiency

[tinkerbill]

Originally Posted by Adventure90

Hey,

I own a 1982 Austin Mini (recently rebuilt) and have always had an eye on getting good fuel economy once the car was finished. It has a Austin Metro 1275cc engine and runs premium, carbureted with a 32/36 DEGV Weber. Has electronic ignition and has gotten a usual 28 mpg.

Mini guy, welcome to the forum. You may not have the access today that I had back in 1969 but I found a Morris Minor intake manifold and single side draft SU carb gave me a consistant 40mpg in my Austin Healy 'bug eye' Sprite. It is probably a little more streamlined than the mini but probably about the same weight and the conversion was quick. I only stuck it on the bug eye for about a month because I got tired of the loss in performance & gas was waaaaaay cheap back then!

[duncan]

Just a warning from the previous comment

You can't just put another SU carb on it - not if you don't want to burn a piston or waste a lot of gas

You need to set the carb up to your engine on a rolling road
SU carbs use a superb metering system using a tapered needle in a jet - there are about a thousand different shaped needles,

On my 1430 mini I changed the intake manifold - just the intake manifold - that made enough difference to melt a hole in a piston

Any carb fitted to a non standard engine will need to be properly set up on a rolling road