Mgf donor car: building an MG Allegro VVC!

[edk83]

Thanks I will have to get back into the mid engine driving style, had an mr2 turbo a few years ago. it liked to lockup at the front into roundabouts and lift off oversteer is a real b*tch! The mgf isn't quite in the same league but I bet they can still be twitchy in the wet.

[Plezier]

Well "Blue" has Pirelli P6000 on the front and have had no dramams and no qualms about driving in the wet and cold and as for beign twitchy well I can only comment on my own driving experiences in the F's and "Blue" on 15" rims feels like the rear tyres tuck under if one does go too hard into bends, corners etc but one has to be pushing really hard and then she does try to snap round a bit. "Elsie" on the other hand running the 16" rims with 40 profile tyres is far more forgiving in the bends. but then she has the correct reinforced tyres walls whilst "Blue" does not and I think that is the real issue there.

[Rob Bell]

Just wondering why you are bothering with the TF subframe? I would have thought that it would make sense to use the MGF rear subframe complete, modified using the MGF front steering components? Then you could use the MGF rear hydragas spheres, and couple these with the existing Allegro rear spheres?

MGF wheels probably a better bet than the Volvo items you've tried - although you'll need rear PCD adapters...

You should be able to retain the wiring loom and the original MEMS2J/ Lucas 5AS combo for better security and instant reliable 145bhp

Great project. Sad but relieved that Allegros are now so rare - else I might have been tempted to build my own!!!

How are you going to stiffen the chassis? Allegros are renowned for having the structural integrity of a damp celery!

[edk83]

I want to get rid of the hydragas and run coilovers as on the tf. Hopefully keeping the Allegro steering rack as the subframe should clear it.

I was running mgf spheres on the front anyway, they were fitted with knuckle extensions and valves to suit, but one side kept going down!

In the long run I may convert the rear to coilovers too. The Tf frame I have is really good, the mgf frame will probably be rusty due to its age.

I will have to get the rear drums redrilled to the correct pcd, no room for an adapter with the mgf offset.

Hoping to use all the mgf loom / make my own. - Will still need a high pressure fuel pump, return line, swirl pot.

I will simply replace all the glass with Perspex once it drops out under flex!! lol and maybe weld in a cage too.

It's going to take a while, but with there being only about 100 Allegros left on the road it should be a true one off.

[Rob Bell]

TF subframe makes sense then

I'd probably go with a TF steering rack, as this fits very close on the back of the subframe and shouldn't interfere with the bulkhead? That said, the pinion gear may not be in the ideal place for the Allegro steering column? Also, the steering ratio may be more suited to the car - the TF rack provides 2.8 turns from lock to lock.

Using the complete MGF loom is a good idea. Shame you won't be able to re-use the ABS! But the MGF wiring loom could mean that you can use the remote central locking with a bit of ingenuity!

Really looking forward to reading how this project evolves. But I also know how long these things take!

[50dwill]

Cheers thanks I will have the aerial when you get time thanks and hope the mob keep away

[edk83]

Well I got the car home, drives nice and straight, runs nice and smooth

VVC isn't working though, rev limiter kicks in at about 5800rpm

All plugs seem present and correct. Just spotted its missing the filler cap on the rocker cover, I would have expected oil everywhere but nope

Tried my obd2 reader to find its not obd2 - doh - VVC might be a pain to diagnose, want to get it sorted before I pull the engine -

Would the lack of filler cap, maybe big vac leak, disable the VVC? Odd as it runs well otherwise.

I was wanting to start this project with a working engine, not be fixing issues before I have started!

[edk83]

Well today I left the battery off for an hour, reseated the cam sensor, put a filler cap on and tried again, no joy.

Unable to talk to the ecu to check for codes :/

Listening to the engine it does sound like the vvc gear is running but cant be sure, will have to try a new cam sensor.

Nice shiney new alternator in there though!

[talkingcars]

A lowered rev limit is a classic sign of a faulty sensor but I don't remember which one, it isn't anything serious.

You need a T4 or pscan to talk to the ECU.

[edk83]

The t4 kit looks quite expensive!

I'm going to try another cam position sensor.

[talkingcars]

T4 is expensive - www.pscan.eu has been designed for the MG/Rover and is much cheaper.

[edk83]

£145 Isnt too bad, I'll probably end up buying one in the long run. Anyone in the derby area got one I can borrow?

Might be able to trade some spares!

[Mykel]

A common fault leading to the rev limiter kicking in early on VVC cars is getting the actuator connectors muddled up. The correct order (from left to right, seen from the inlet manifold side) is blue - brown - black, blue to the decrease solenoid, brown to the increase solenoid and black to the oil temp sensor in the vvc mech housing.

Been there, done that.

[edk83]

Here is a pic of mine, taken from inside the car. So I have the brown and black connectors the wrong way then?

[edk83]

Are you sure the black connector should go to the oil temp sensor. The thread below says otherwise and mine would be correct.
Also the oil temp gauge on the dash works fine, although this could be getting it's signal elsewhere.

viewtopic.php?f=8&t=7140

[edk83]

Just checked the vcc plugs and each one has the thick brown wire with pink trace, smaller wires going to the plug on the temp sender so unless the blue and black are the wrong way round its not that.

[Rob Bell]

The pscan.eu may be a good investment for you.

How is the lower rev-limit manifesting? A hard cut off (ignition cut out) or a failure to rev any further? There could be a sensor fault, or there may be a problem with the VVC solenoid.

[edk83]

Hi

Yeah being able to connect to pscan would help and seeing as I'm going to be dealing with these engines for some time to come it could help.

The 5800 rpm limit feels like ignition cut, it will sit and bounce off the limit and wont go any higher at all. The intake pipe isnt getting crushed or anythng. Doesnt matter if engine is under load or if the clutch is in, just bounces off 5800.

Going to try another cam sensor and maybe change the solerniods.

[edk83]

I put a thread in the tech section about the rev limit hoping to get some extra help from the mgf experts.

So far tested the cam sensor, works
Oil temp sensor resistance goes from 3k to 1k when engine is warm so I reckon that's fine
Solenoids have a resistance of 8 ohms each so all good
The power to the solenoids is good
vvc cams and main cams are lined up fine

So only the map and ect sensors, ecu left then it's onto stripping the vvc

I did start attacking the interior though, chromed wing mirrors are sold, all other bits available for sale as long as I can keep the engine going.
If I can raise a bit more cash I will buy a pscan.

[bod1066]

Hi, if someone had the head stripped down, they have set up the cam shaft timing wrong, the long steel rod that connects the vvc together will be out. I have seen this on a number of times, you can check this on testbook at idle, atb Dave.