spi to carb conversion

I have been thinking of converting my spi mini to a single 1 3/4 su carb. Anyone know where I can get information on doing this? Also, if I do this, do I have a problem at MOT time?

Reply to
flash harry
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Is your Mini a Cooper 1.3i as mine is a 1990 Mini Cooper 1.3 (Mainstream, ie not RSP LE) and has a single HIF44 carb which has always been fantastic.

But why do you want to change from fuel injection? Even if you do fit a carb and are able to get it through the MOT, your more likely to have grief getting your car to pass the emissions test then because of it's age.

Basically their not so strict on older Mini's with carbs as such, but their much tighter on later Mini's and I doubt you'd pass without fuel infection?

Reply to
Taffy

Yes, mine is a 1.3i The reason I am asking about a carb conversion is that I recently had a real problem getting my mini through its exhaust emissions part of the MOT. I wondered if changing to a carb would cause more problems with the MOT but thought that at least I would be able to tune the setup instead of just having to trust the ecu. Thanks for the advice - more for me to think about.

Reply to
flash harry

The MOT emissions are based on the production year of the engine or the year of the car/chassis - *whichever is the earliest*. Best idea is to plonk an early MG metro engine in, making sure original engine plate/stamp is present & correct. You may neeed a letter of proof though from BMH as to production date of engine, a copy of the donor cars logbook may help too. Honestly, to get this up and running you will only need a positive feed from the ignition to the metro dizzy, forget about faffing about with ecu and carb conundrums! Injection was only put on mini's to pass ever stringent emmision eu tests, though twinpoint does an excellent job.

Simplest way to increase performance is to fit the 3.4 diff, again they only used the 2.7 to satisfy eu bods with their drive by noise limits (as mini has no 5th gear).

Chris

Reply to
Chris

change plugs and leads, change oil (old oil can absorb unburnt petrol and when it burns it can put your hydrocarbon count up!), change air filter would prob make big diffrence, make sure exhaust is sound with no leaks anywhere, also there is a 'max rpm' that the emissions test can be carried out at - make sure tester is not just leaving it at idle but revving it to just under this limit.

take it for a good thrash before the test to get it good and warm! ;-)

Most mini's pass on CO but fail on HydroCarbons.

Chris

Reply to
Chris

Well the Twin-Points were 2.7 where as most Mini's from 1982 up to the Twin-point of 1996 had a 3.1 diff. Okay a bit sluggish on hills and through the gears (but you can go further with first generally) than the 3.44 diff, but the 3.1 tends to be more economical and happier/smoother on motorways. But then it's even more so on the 2.7.

Taffy

Reply to
Taffy

Well as it happens I forgot that some folks have indeed converted their engines to carbs from injection. Then there's firms like Downton who used to take an injection Mini and Mini Cooper and retro fit it so it ended up looking like a Mark I Cooper S complete with twin carbs too! Even John Cooper garages did a 1400S conversion with twin carbs.

So if these options were MOT friendly, then I guess there's nothing to worry about except the expense. Well you'll probably need a new inlet manifold, manifold and exhaust system for starters. But if it's a post

1991/92 model, it has to retain the cat for the MOT too! Then there's the electrics to sort out, which can be a nightmare if your modifying things, so it's not something for the faint hearted to take on!

No i'd do what Chris suggests and get it thoroughly serviced and perhaps fit a K&N filter too? There's an easier option to get it through the MOT than resorting to drastic measures, especially fitting a complete new (or old in the case of an MG Metro engine) engine!

Reply to
Taffy

can i ask what is the fuel consumption like? if it is way too low, change the LAMBDA sensor. this governs the air/fuel misxture, and if it is dodgy, your engine will run WAY too "rich2 - ie too much petrol per air. thus- fuel consumption is crap, and CO and hydrocarbons are thru the roof as the engine cant burn all the petrol

HTH RS

Reply to
RS

Okay I told a bit of a fib, as the John Cooper Garages 1400S conversion, when applied to injection cars retained the fuel injection system, but uprated it, although I can't give any exact details right now as the site with the information on has just gone down, other than it was very expensive, but made your Mini fly like a jet fighter!

Anyway I know Downton used to remove the fuel injection and replace it with twin carbs as I have it featured on a Mini video!

Taffy

Reply to
Taffy

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