2.5 hs6 carb linkage

[Davemate]

I've got an "s" type inlet manifold and hs6 carbs, a mk2 throttle pedal bulkhead plate and cable.
Can some kind person just post a picture of the carb linkage and cable holder as my carb are from a sprint and I've only got the carbs and a bare manifold
Cheers chaps

[AlanChatterton]

Any good?

[Davemate]

Yep
Cheers

[Rod 2500S]

The auto gearbox kick down goes on the rear, unused, hole in Alan's pic. Also you can have the choke on either carby, pic shows on the front, mine is on the rear for a standard 2500S with auto box. You may find some difference in the return springs as well.
Nice work Alan, extremely tidy
Rod

[Davemate]

Anyone got a linkage up for grabs,seems to be non of the usual places has any.

[piman]

Hello Dave,

have you tried Burlen? :- https://burlen.co.uk/

Alec

[Davemate]

Alec, I've had a look and they don't list the bit I need
I can sort the connecting rods between the carbs
It's this bit I need

[RobPearce]

Let me have a dig in the bag of old bits. We dismantled a 2500S (actually a 2000Mk1 but on S running gear) many years back and I've quite possibly still got that bit.

[Davemate]

9716 wrote:

Let me have a dig in the bag of old bits. We dismantled a 2500S (actually a 2000Mk1 but on S running gear) many years back and I've quite possibly still got that bit.

That would be good.
Go look now !
I'll send money  ;)

[RobPearce]

1344 wrote:

That would be good.
Go look now !
I'll send money  ;)

I'm at work right now  :P;) but I'll look this evening.

[Davemate]

9716 wrote:

I'm at work right now  :P;) but I'll look this evening.

Any joy ?

[DJB_Harvey]

I should have linkage bits as well if struggling ....

[RobPearce]

1344 wrote:

Any joy ?

No, sorry. That doesn't mean I defintiely don't have one, just that it's not in any of the places I'd expect to have put it.

[Davemate]

Sorry chaps,God knows how I missed your last two posts  :B

Rob
Cheers for looking

Dave,
    If you have one knocking about ,then yes please can I purchase it  :)

[Tony68]

[quote=1344]Alec, I've had a look and they don't list the bit I need
I can sort the connecting rods between the carbs
It's this bit I need
(pic deleted)

I don't think much of that linkage. I had to modify it heavily in my car (okay, it's a vitesse, but manifold and carbs are straight from late 2500TC) just to get the throttle action nice (pedal weight, linearity, etc). I think a piece of Meccano or Dexion with a single arm would do as well. Also, it may not be obvious from the pic, but the rest of the linakges on the setup are very good, allowing each carb to have its slow idle set independently (unike the cheapo Stromberg arrangents) and so on.

[RobPearce]

The complicated linkage is designed to provide slower throttle opening at light throttle (where small changes make a big difference) but swing the butterfly open quickly as the pedal is pressed further down (when small throttle changes make no difference). This is a Good Thing and nearly all modern cars do it one way or another (often by having Very Complicated Mathematics in the ECU to decide upon the throttle target).

The cam-and-roller method on the 2500S isn't the best. It has a very noticeable knee point between the slopes, which feels like the end of pedal travel to a driver more accustomed to a Mk2 Spitfire. However, it does give better throttle control / linearity than "a piece of Meccano or Dexion with a single arm".

[Tony68]

9716 wrote:

The complicated linkage is designed to provide slower throttle opening at light throttle (where small changes make a big difference) but swing the butterfly open quickly as the pedal is pressed further down (when small throttle changes make no difference). This is a Good Thing and nearly all modern cars do it one way or another (often by having Very Complicated Mathematics in the ECU to decide upon the throttle target).

The cam-and-roller method on the 2500S isn't the best. It has a very noticeable knee point between the slopes, which feels like the end of pedal travel to a driver more accustomed to a Mk2 Spitfire. However, it does give better throttle control / linearity than "a piece of Meccano or Dexion with a single arm".

It certainly *should* do! But mine feels much better since I took the cam and roller off and reverted to a single arm. I was aware of the reasons for the original arrangement, and my alterations make use of different angles on the arms at each end of the operating rod to give an equivalent variable-ratio effect with less friction.
I did takes some pics to show this, but they don't very well; essentially, the driving arm starts at an acute angle to the rod and the carb arm starts at a right angle, giving about 2:1 reduction, and at full throttle the positions are reversed to give 2:1 gain. The bonus is that the throttle return spring tension is also multipled to give increasing force with throttle, which I like.

I agree that some non-linearity is essential, though. Without it, touching the throttle lightly on a big six is like being hit in the back with a sledgehammer :-)
And if you have big feet like me and accidentally catch the throttle when braking, the throttle tends to win which wakes you up pretty quickly  :'(

[Shed 1969]

Think ive got one..do you still need one?

[Davemate]

8861 wrote:

Think ive got one..do you still need one?

If that's aimed at me,thanks but no thanks. Mr Harvey has swapped me one for some beer vouchers  :)