25 replies to this topic

[Mrpeanut]

Mine (same car, carb and dizzy) did the same but at 3500. It was fuelling. Needle was changed at the rolling road.

Are you running a standard head and exhaust?

[classicoop]

Standard head, gutted cat, straight exhaust.

 

Well I think it's a standard head. Got the car used.

[Mrpeanut]

If you're running a stage 1 type exhaust you may benefit from a different needle, perhaps a Bdp or Bdl

[classicoop]

Checked distributor, springs / weights are clean and move freely, dizzy diaphragm holds vacuum.

 

No pinking, so I guess mixture is fine. Adjusted mixture lean just before rpm drops, also tried 1 then 2 turns rich, same result.

 

What RPM do you guys usually run out of power (standard 1275)?

[iwatkins]

On our 1275 power starts to tail off around 5600rpm but will still rev easily to 6500rpm

[Cerberus]

On our 1275 power starts to tail off around 5600rpm but will still rev easily to 6500rpm

 

+1 on that for my 1275, although I don't think I've ever been up to 6500 as it feels like it's starting to try and go back to the future,

[classicoop]

On our 1275 power starts to tail off around 5600rpm but will still rev easily to 6500rpm

 

Thanks for the info. There's definitely something wrong with mine.

 

 

 

+1 on that for my 1275, although I don't think I've ever been up to 6500 as it feels like it's starting to try and go back to the future,

 

 

Mine feels that way at 4500k+ lol.

[classicoop]

 

5 degrees isn't enough, if your setting your timing at 6 degrees this would give you a maximum advance of 11 agrees. Or in other words about 19 degrees short of what you need.

 

 

 

It was 6 degrees at around 1500rpm last I checked. Using a non-adjustable strobe.

 

I'll try adding timing til it starts knocking, can the nut holding the distributor be loosened with the grill on? It's just a single nut right?

[classicoop]

So 6 degrees at idle and then it adds about 5 degree's (your estimate from other thread) which if you  tested it as I suggested means the maximum advance above about 3000 is eleven degrees...........Which isn't enough for the A series engine, it needs to be nearer 30 degrees all in (30 - 11 = 19).

 

I told you in the other thread, to check the bob weights are hitting the advance stop pin, are they ? Just because there moving doesn't mean they are working correctly. If they aren't hitting the stop pin you won't be getting enough advance, which surprise surprise is what is happening here............

 

No it's 6 deg @1500rpm w/o vacuum hose. Then above that I don't know. The strobe I got isn't adjustable (timing set knob). I need to get a better one.

 

From Haynes = (v) = 5º + 1º BTDC at 1500 rpm. I don't quite understand the 5 + 1. Does it just mean 6?

(v) Mini Saloon and variants, 1275 cc, 1990 on (electronic ignition)

 

What should I set the timing to? 

[classicoop]

Replaced fuel pump with a Facet SS501, mechanical is still bolted on car but not to fuel lines. Did a quick 2nd gear run, it seemed to rev a bit more freely past 4k. Even reached 5500rpm. But it took it's time.

 

Gona do more tests tonight.

[classicoop]

Did a couple more runs, it did feel livelier past 4500. Might be placebo effect though or less load on motor since mech fuel pump isn't loaded anymore or maybe there was fuel leak before and carb wasn't getting enough fuel at high rev.

 

Thanks for the help everyone =)