I'll have a go at adjusting the pump stroke again. Hopefully that is all it is.. What pump jets should I be using? I'll check which one's I've got. Maybe that is the issue..

I had a feeling it could have been flooding aswell, so I tested it with a colour tune.. and it showed up as starving.. If it were flooding instead of starving what would that mean?

I run a dellorto and prefer my dellorto over an SU any day of the week. It's also tuned and setup properly on a dyno. With the SU that was on it before i could stomp on the throttle from about 1000rpm and it would just pull away no fuss.

With my dellorto, if you stomp on the throttle off cam (below 3000 rpm) it will squirt too much fuel into the chambers and bog a little before it picks up.

Every weber/dellorto fed mini i have driven is the same, but hey, maybe no one knows how to tune them like you said?

The dellorto is ALOT more sensitive to throttle inputs than the SU was and that's great, just the way i and alot of other's like it, but i still stand by what i said, you can't drive it like it only has two positions. on or off like you can with an SU.

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

Go for smaller pump jets and your problem will dissapear as its designed only to enrichen the mixure enough and only on initial downward movement of the throttle and stops working after the throttle is open and then the idle jets controll the fuel flow untill the mains take over, simple really but most dyno operators only check fuel mixture when the car is working its nuts off and producing horsepower and high revs. I have had to fix cars at the track that have had long dyno sessions and are totally bloody undrivable because of bad setup, produced 5 more horsepower at the top end but you couldn't drive the thing on the street or the race track, great for the drags but useless otherwise

Jon

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van

Well I just checked and my pump jets are 35s. Should they be smaller/larger? Or is that about right?

mate what size is the engine and what if any mods do you have on it, a 1275 with a 45 mm will normally have around 40s for pumps, its hard to judge without knowing all the motor details

Jon

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van

Oh yep sorry, well the enigne is a 1098 with basic mods, extractors, slight head work, kent 266 cam..

Mate there are lots of things to think about, what size is the carb 40 or 45 what size are the chokes in the carbs, for a 1098 a 40 would be the carb of choice with 30 or maybe 32 chokes but that would be probably on the edge for being a little to big, with 30 mm chokes your 35 pump jets may only need to go up to 36 or 37 pumps, probably good to find a good Alfa mechanic up there, they will have a range of carb bits for Dellorto

Jon

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van

Carb size is 40.. Pretty much everything else should be correct. I went accordingly to what other people have tried and proven for my size/spec engine.

I adjusted the pump stroke all the way up, as the flat spot was getting less and less. I did it all the way up, but the flat spot was still there, not as bad but still there. So would this indicate that bigger pump jets are required? Do you think just 1 or 2 sizes up should be fine?

Honk

like all things machanical it all depends on the car, like I said you might get away with only a couple of steps up in pump jets but it might need to go up 5 or more you won't know untill you try and you might need to change the idle jets as well, its often cheaper to get some one good up therre as it really is hard and can be expensive to just keep buying bits and shoving them in just to try, a good tuner will have the bits at hand just to try, ask the list for some places up there that may help, I know Grieg Malure is up there and has a dyno and may be just what your looking for

Jon

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van