Jag airflow meters

[The Hatter]

Hi All,
Playing with the SEAC... the original flapper is a Lucas 73171B (Jag XJ6 4.2) and it rattles, so FUBAR I suspect. I have another Jag XJ6 4.2 flapper but it's marked 73172D so I suspect it's wrong for the ECU.

If anyone has a larger capacity flapper V8 with a Jag AFM can you check the number and post/mail me? Or else, does anyone know the meaning behind the different part numbers?

[gmw9666]

Legend has it that only 1 is suppose to work, all my previous Jag ones have ended in B

Also here is an extract from the Des Hammill V8 book

[batman400]

I'm using the 73171B on a 3.9 with 4.2 injectors with a STD Non Adjustable ECU.

[KKson]

I've two for the 390 and from memory both end in 171B. Once Mr Adams has worked his magic, promised at the end of the month, then one will be spare.

[The Hatter]

Thanks for the replies gents, that answers my question. I spotted the right part on ebay so I've ordered it, unfortunately before I saw your post Keith!

[adam quantrill]

How many horses is it worth and how much different does it look from the outside?

[The Hatter]

In isolation I'd not expect anything out of the Jag AFM; but the SEAC has ultra-big valves, a heavily ported inlet manifold and jag injectors. I'm not sure if the ECU is different or not.

[RCK974X]

Not sure what you want to do, but in case you didn't know, ALL the Bosch built airflow meters are adjustable, although it's complex to do.
Don't know if jag ones are Bosch sourced, but might be

[The Hatter]

The Jag one is marked Lucas but it may be a rebadged Bosch - I suspect it is Bosch manufactured as there's a Bosch style part number moulded into the plastic cover and the lucas name/number is on a sticker.

The Jag part is larger bore and so a different housing, with different mounting bolt locations.

I know you can adjust the spring tension of these units (some folk say you should never do that but with the help of an AFR gauge I've done so with success), I'm not aware of anything more complex in terms of adjustments.

[barrington]

you can play with my one martin

[RCK974X]

The Hatter said:

The Jag one is marked Lucas but it may be a rebadged Bosch - I suspect it is Bosch manufactured as there's a Bosch style part number moulded into the plastic cover and the lucas name/number is on a sticker.

The Jag part is larger bore and so a different housing, with different mounting bolt locations.

I know you can adjust the spring tension of these units (some folk say you should never do that but with the help of an AFR gauge I've done so with success), I'm not aware of anything more complex in terms of adjustments.

Yes, sorry, I meant that it's not just a screw adjustment, and that you have to take unit apart and break the glue - but web articles explain quite well....

Just thought it might be a useful tip....

[mk1fan]

Does this mean the original engine is getting close to being refitted?

[The Hatter]

Yep useful tip, thanks Andy. There's a useful contribution from the God Of Wedges out there. Wedgeneering.

The engine's very close as I type, I can touch it with my toes under the table! Unfortunately the car is not so close to it...

[billynobrakes]

The Hatter said:

The Jag one is marked Lucas but it may be a rebadged Bosch - I suspect it is Bosch manufactured as there's a Bosch style part number moulded into the plastic cover and the lucas name/number is on a sticker.

The Jag part is larger bore and so a different housing, with different mounting bolt locations.

I know you can adjust the spring tension of these units (some folk say you should never do that but with the help of an AFR gauge I've done so with success), I'm not aware of anything more complex in terms of adjustments.

Be careful of afm copies with Bosch numbers and Lucas stickers on as they are cheap Chinese copies, how can you have a mixture of both trust me it cost me £1000 after the cheap copy failed to run the engine properly, it's not worth skimping on price