Amal mk2 34 pj on a 225/fresco

[Nobby]

Hi could someone give me some ball park jetting figures for a mk2 Amal please, st5/6 tuned 225 with fresco, and also how do people usually block off the power jet? I heard you just don't fit the rubber around the bellmouth? Is that right?!

Cheers....

[DaveTomo]

Jetting off the old AF site, may get you in the ballpark

[DaveTomo]

Picture from a few years ago when I run a MK2 concentric - pretty sure I only put the rubber band around ran OK,also the best induction noise of any carb.Like I say a few years ago so can't be 100% sure.

[Warkton Tornado No.1]

Hi

I can’t give you ballpark figures, but from what I can recall, power-jets were kind of in their infancy when I used that set up. I think you are right in that removal of the bell-mouth feed moulding did disable them. I can’t recall having to do anything else.

However, power-jets were de-rigueur on piston ported engines & not reed valve.

Looking @ the AF chart (posted above) those main jet sizes seem huge from what I have in my Amal jets stock, which would have been used on a barrel with a similar state of tune to your set-up.

Sorry I can’t help more….

[Nobby]

Cheers davetomo and warkton, nice info

Someone else gave me this-

3 or 31/2 slide 40 /45 pilot 2d1 needle 300 to 350 main ,,,as a start point ,,,ans 307/308/309 attomizer ,if i remember correctly


So Iv got some idea now , Anyone else got any figures... The more opinions the better, will get this dynod when it's run in but till then....
Cheers......

[rossclark]

Those AF figures are for non PJ.

PJ + MJ should roughly equal those figures.

[Nobby]

Mj?

[rossclark]

Main Jet

[Nobby]

Deh! Taxi for Nobby....Cheers!!

[Adam_Winstone]

Asked Paul yet? He put a lot of time and effort into testing and adjusting his on his iron 238.

Word of warning... you'll get a lot of different answers from a lot of different people, even with this old carb, e.g. when I was asking about jetting for a standard TS1 225, with a range of common pipes, I had combinations of 107 with 410 MJ up to 109 with 320 MJ and a range of 4, 3.5 and 3.0 slides. Even after decades of people trying to find a common set-up, advice varied wildly. One of the UK's top tuners stating, "I've never set a TS1 up with a 107! You'll want a 108 or 109."

Paul can give you his details and I've got mine from my iron 240 if you want them.

Adam

[Nobby]

Could someone tell me if number 15 is the power jet blanking screw??, or any tips on blanking the power jet... Or how I find out what size jet the power jet is?...

Cheers....

[Nobby]

Asked Paul yet? He put a lot of time and effort into testing and adjusting his on his iron 238.

Word of warning... you'll get a lot of different answers from a lot of different people, even with this old carb, e.g. when I was asking about jetting for a standard TS1 225, with a range of common pipes, I had combinations of 107 with 410 MJ up to 109 with 320 MJ and a range of 4, 3.5 and 3.0 slides. Even after decades of people trying to find a common set-up, advice varied wildly. One of the UK's top tuners stating, "I've never set a TS1 up with a 107! You'll want a 108 or 109."

Paul can give you his details and I've got mine from my iron 240 if you want them.

Adam

Forgot he was using a mk2 Amal!.... Will find out.... Ta!

[Dimitrios_231]

Could someone tell me if number 15 is the power jet blanking screw??, or any tips on blanking the power jet... Or how I find out what size jet the power jet is?...

Cheers....

I think that part 2622/142 originally was for blanking the pilot jet,but it can probably do the job that you want (convert a PJ carb to non-PJ).
If you run without filter start with 108 needle jet minimum.

Two pics,they might help,might not,you need to do the opposite task.

[Nobby]

Thanks dimitrios!, Iv ordered that jet blanker- £2 so it's not going to break the bank,