Reinstating PI to a carb converted car

[Snoozin]

Right, so I am purchasing another complete (but crashed) Mk2 PI saloon... which has all the PI stuff present (however the inlet side is all removed due to the guy removing the exhaust manifold).

It's a 1974 car, mine's a late 1973... so should all the injection gear be a lift off and bolt onto mine with (hopefully) minimal fuss? Ie: there should be no differences between the gear used on either car?

I have read about 'green' and 'black' top metering units - is any of this relevant to my situation? The car I am purchasing has the green unit on it fwiw.

Otherwise, other nice parts include a spin on filter kit, a 2" exhaust, full leather in great condition (which I will likely sell) manual OD box, new front suspension and a good diff.

If there's anything I need to watch out for, please advise - the metering unit has been recently reconditioned, with receipts apparently so I'll be keen to verify that.

Thanks, Rich

[TedTaylor]

Should be a straightforward swap over.  

The different coloured MU tops relate to settings for 135 or 150 BHP.  I think what you have is correct but not an issue, as far as I have been advised, unless you have problems with flat spots etc.  Besides if it is a recon unit fitted to a properly set up engine it is most likely the correct one but you can always contact the supplier to check, if you have the receipt.

Ted

[Richard B]

Well, couple of things.

The green top is the 125bhp TR6 and Saloon later unit. The throttle bodies have a rather awkward linkage on them as standard. I know Revington TR do a rather expensive conversion, Malcolm at Prestige may be able to offer a cheaper alternative.

What engine serial No. do you have? (first few letters and numbers)

The 132bhb cam will not run well with the 125 MU. If you have a 132 cam, either have your MU changed to suit (by Malcolm or Neil Fergusson (eBay)) or get a black top MU.

Rest of the gear should all be the same, injectors, pump PRV, main pipe runs, pedastal, dissy drivegear, plenum chamber etc...

[andy thompson]

3019 wrote:

Right, so I am purchasing another complete (but crashed) Mk2 PI saloon... which has all the PI stuff present (however the inlet side is all removed due to the guy removing the exhaust manifold).

It's a 1974 car, mine's a late 1973... so should all the injection gear be a lift off and bolt onto mine with (hopefully) minimal fuss? Ie: there should be no differences between the gear used on either car?

I have read about 'green' and 'black' top metering units - is any of this relevant to my situation? The car I am purchasing has the green unit on it fwiw.

Otherwise, other nice parts include a spin on filter kit, a 2" exhaust, full leather in great condition (which I will likely sell) manual OD box, new front suspension and a good diff.

If there's anything I need to watch out for, please advise - the metering unit has been recently reconditioned, with receipts apparently so I'll be keen to verify that.

Thanks, Rich

If your car is post MG75000 engine number the green top unit will be fine. It was designed to give slightly more accurate fueling and was used on 74 and 75 models as a refinement in a last gasp attempt by Triumph to improve emmission etc.

Manifold wise unless you are very lucky and have a set of unworn late (twin vacuum pipe) manifolds off this scrap  PI, you are likely to find them a sod to set up. Earlier (1972 and older) manifolds are easier to get synchronized and that is the key to decent mpg and part throttle smoothness with a Lucas PI.

[Snoozin]

I seem to remember this car having single vac lines on the inlets... I could be incorrect though. And the MU is definitely a green top unit.

In a months time all will be clearer. For the money it's too good to turn down as it is.

[andy thompson]

Late 73 engine on yours and a reconned green top will work fine if its the original engine in yours. TBH PI fueling is not as critical as everyone makes out. Most reconned units when recalibrated to original factory settings will not  give ideal mixture as every engine is different after 35+ years and fuel is very different to 1970. Best fit it, set up the peripheral stuff properly,  monitor it and then tweak as/if required.