Converting SPi engine back to carb and electronic dizzy

Hi.... I have installed an unleaded 1275 A series in my Mini and am having 'funnies' with getting the power across the whole rev, range. I have a HIF44 carb with LCB and 2" exhaust system to a DTM twin tailpipe box. I have a dizzy with electronic amplifier block from a Metro. Whilst the car has plenty of 'grunt' at low speeds it is 'breathless' at high speed only managing 70mph or 80 downhill, so is useless when overtaking! The mixture looks OK as far as MOT goes and the exhaust is slate grey, the plugs light sand colour. What I am wondering is if the dizzy has the wrong advance curve or the needle the wrong profile. Has anyone successfully done this retro conversion and how.

Thanks in anticipation...

Dave

Reply to
Dave Bullock
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Well Dave the best way to get it all set up right would be to put it on the rollers at a good engine tuner, that way they can find the perfect needle and sort out your dizzy advance too.

Still a 2" exhaust is a tad too big for a standard engine and i've heard 1"3/4 or no more than 1"7/8 would have been more suitable perhaps? But I doubt the exhaust would affect the maximum speed though?

Taffy

Reply to
Taffy

Hi Dave,

if the Hif44 came from a Metro then the needle is suspect, BDL might be a good starting point. Is the air-filter new/clean? Does the engine show the same symptoms in first and second gear? you may have a gearing(diff) issue; you could also check the general condition of the engine? compression test; how many miles has it had? standard top for spi would be around 90 mph, maybe you just have a very tired/worn engine ...

HTH, Theo van den Bogaard

Reply to
t.a.j.m.vdnbogaard

Hi Dave all good advice there mate, theos advice regarding check engine condition and needle, taffys advice on rolling road, etc I can only say the same things, rolling road set up with correct needle, I have a City E (1ltr) that is totally standard, and it regularly top

90/95mph,,, I would expect yours to top 100/105mph possibly a bit more after a R/road session, good luck Fitzy
Reply to
Fitzy

Well I got a BFY needle as standard in the HIF44 carb on my 90' (Mainstream) Mini Cooper 1.3, but after fitting a stage one kit and K&N Cone type filtercharger, I was recommended by Mini Sport to fit a BDP needle instead and it runs very well, but I do want to get it set up properly on the rollers soon.

Anyway try this site out and contact the Mini Guru there who has a regular column/feature in Mini Magazine for expert help too, but i'm sure he'd recommend you get it set up on a rolling road first anyway:-

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Taffy

Reply to
Taffy

Thanks Guys, I have a terrible admission to make... we spent the afternoon checking stuff out and found that the ferrule that terminates the throttle cable at the bulkhead had split and was allowing the outer to move (reducing the overall travel of the accelerator cable) It must have been a gradual process as I hadn't noticed the accelerator pedal was lower than normal. So the car now will do 85mph and has much better acceleration, (pretty impressive actually). I had already done the compression checks and the oil pressure is 75lbs (cold) 30lbs (hot) the engine has done 35K miles and is good. However as Fitzy says I feel that it should go even quicker, and when we put it on a gas analyser (admittedly not under load) it goes weak at high revs. So maybe needle? Also we checked the max centrifugal advance of the distributor I am using. It peaks around 15 degrees at 2000rpm! Finally last night I found an article about converting the SPi engine back to carb and electronic ign on the Mini Mania site. They reccommend Mini A+ distributor so....does anyone know where I can find the centrifugal and vacuum curves for such a distributor? Thanks for all your help......Dave

"Taffy" wrote in message news: snipped-for-privacy@h48g2000cwc.googlegroups.com...

Reply to
Dave Bullock

Dave....no-one really gives a shit about your pathetic life,,,,go away.

Reply to
Barpseed Beta Version 3.0

Reply to
Barspeed Beta Version 3.0+

Thats OK

However as

Thats what it should do. Its normal to check the gas at 2000rpm and as you do increase the revs should go weaker.

Ill have to look up the curves later if someone else dosen't come up with them in the mean time,

Reply to
Rob

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Madmax

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Barspeed Beta Version 3.0+ Real Barspeed

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Reply to
Madmax

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Madmax

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Madmax

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Madmax

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