TR6/5 CP throttle links

[spitfire6]

Hi,
my CP exPI, EFI Engined 6 is running kak due to poor synchronisation I believe.
Have removed the three non-OEM ball-jointed links & they are getting replaced as not as slick as were.

Have been looking at the OEM replacement type with the finer thread & single screwdriver slot for adjustment.

When my existing ball jointed type was secured to the arms with an M6 nut the ball joint allowed rotary movement. How does the OEM rotate?
It seems if I tighten the nuts to the arms there will be too much friction. Do I fit the nuts loose and rely on the spring washer to prevent the nuts from dropping off?

Cheers,

Iain.

[RedRooster]

Do that and the nuts will fall off, can you use sleeves? 

 

[Nick Jones]

The OEM ones have a shoulder on them that go through the operating levers and are long enough that when you tighten the nuts, they remain free-turning. The issue with those is that both shoulders and levers wear producing slop that makes accurate setting impossible, even with the fine threads and what-have-you. This is a problem as the large (excessively) butterflies make it all very critical.

[spitfire6]

Hi,
That makes sense. But now I worry that the holes on the lever arms are the wrong size- will check in the morning- and I guess/hope the shoulder is 6mm OD.
ball-jointedIt looks like the ball jointed ones would be more forgiving with slight angular errors.

Ordered from Moss yesterday but a little worrying as the money has not been taken yet. I wish I had built my own now, the hardest part to find was a suitable thread bar. Unfortunately, I don't have the time to order parts and test.

Out-of-sync butterflies & the TPS that gets noisy around idle speed sucks. 

Thanks,

Iain.
 

 

 

[Nick Jones]

9 hours ago, spitfire6 said:

Out-of-sync butterflies & the TPS that gets noisy around idle speed sucks. 

Absolutely does!  Can't remember what cam you have fitted - this isn't advised for the wild ones, but have you considered trying a single TB?  You could simply get another plenum, weld a plate over the open end drilled and tapped to match a suitable throttle body (something around 60mm - ish), built-in idle control valve optional if you wished to explore that (I think the Emerald can control a PWM one?).  You wouldn't even have to modify the TBs themselves initially - just wire them fully open.  Instant automatic balance..... and a sensible throttle range - possibly even a usable MAP signal....  (some breather adjustments maybe needed dependent on what you have - full vacuum to engine not advised!)

 

[spitfire6]

Hi,
linkage arrived. The holes on the bottom of the prestige kit fitted in 98 were too small. Conecutter used & holes now big enough, +/- 100 microns. Not have to worry about them ever sticking, LOL.
Bit of packing with JB weld and will be sorted.

Someone in the States is selling a single TB kit for £1500. Unfortunately, I am not an expat anymore.

Cam is unknown. Misfire is always at idle. cannot sense it but the exhaust smell is sweet/sickly depending on your age. Lamda assumes complete combustion and displays 1 or 14.7.

My idle speed is set with the OEM air-bled screw. It takes air through an inline PCV connected to the rocker box. Air interest through the OEM mechanical fuel pump blanking plate. Oil consumption is much lower than in previous systems. I do need to fit a 3 or more wire ICV. A stepper if the price is right.

I know I have fucked up on the holes. I can feel it when nuts are tight.. It's going back on the car so I can book its MOT. 

Cheers,

Iain.

 

 

[RedRooster]

Do you still have to do MOTs for classics in the UK? 

[spitfire6]

12 minutes ago, RedRooster said:

Do you still have to do MOTs for classics in the UK? 

Car my age no. My car is not exempt. Too many mods.

[Nick Jones]

1 hour ago, spitfire6 said:

Car my age no. My car is not exempt. Too many mods.

Bit of a grey area that. If originally registered as a Spit, yes probably.

 

[spitfire6]

Nightmare.

New arms are too short- Only 30% throttle maximum.

The rear TB lever arm hole is too small

Going to waste more money and build my own.
Any anyone know a source of LH/RH 100MM long M6 1mm thread bar?

 

[Nick Jones]

https://www.mcgillmotorsport.com/m6-turnbuckle-link-nuts-|-adjustment:-100mm-130mm-linkage-6mm-c-97-p-1142
 

 

 

[spitfire6]

Cheers, I was going the other way.

[spitfire6]

Just bought this from eBay.

Recrimped the pot.
I will refit pot tomorrow and fudge the pot so that it reflects the true range of my system and go for a drive.
Maybe not as the pot is causing friction & it is not spring return.

Cheers,

Iain.

 

[Nick Jones]

Is your pot linear or logarithmic? Throttle pots are typically but I do wonder if logarithmic would give a better result due to the need for more resolution at the bottom end?

The BMW bike one I have on mine has twin overlapping tracks which I’ve connected together giving a non linear scale with more resolution at at low throttle openings.

[spitfire6]

Hi.

It's linear. Only ever seen linear.
I've found the good ones give a range/span of 0-1023. 10 bits. Input is 11 bits. Around 500+ is the full span of the TPS fitted.

My K3 will only see around 180 span max. Cant use autocalibrate of course. Whatever it is I will do some math and hard write it into like ECU config. Good it's there!

I wish the angle was sorted with a mechanical snail thing.
 

[spitfire6]

 

Hi,

I decided to fit a TPS without the flying leads, an integral male timer connector instead. Delphi (BMW). It is not a spring return type.
It is non-linear (Log). I also suspect it is CW. My throttle is CCW!

It's also a pain that I have no mechanical adjustment.

Cheers,

Iain.

 

 

[Nick Jones]

Logarithmic will be an advantage, but only if it works the right way!

[spitfire6]

If it is Log it's getting removed- it will be worse than ltnear if it is reversed!

Going to have to go back to the wired webcon type.

[Nick Jones]

10 hours ago, spitfire6 said:

it will be worse than ltnear if it is reversed!

Absolutely!