SLANT 4 IN A VIVA

[Tokyo-Grift]

Hello all, I know the magnums came with the slant 4, however can anybody clear this up for me. Will it fit in a viva HC no problem? Its from a victor so I know I will have to take the sump from my 1256 to clear the subframe. But other than that engine mounts are fine? And will the 1256 manual gearbox fit onto the 2.3 slant 4?

Thanks in advance!

[1972nail]

Unfortunately the slant 4 drive train is completely different to the OHV Viva drivetrain. You need complete OHC Viva/Magnum running gear to do the conversion you're after. The sump and gearbox from a 1256 will not fit a slant 4 and the engine mounts will not suit either.

The OHC Victor engine needs a Viva/Magnum OHC sump, pickup pipe, dipstick and exhaust manifold to fit into the HC engine bay. You will also need the Viva/Magnum OHC front subframe, gearbox (Victor one has a different gearchange linkage) propshaft and back axle. Other things on your shopping list would be the OHC wiring loom, alternator, servo and gearbox tunnel cover plate.

[lord13]

^^^ This is not strictly true, although you will need all these parts to do it properly, there are ways around it.

You will need a sump from a OHC viva, the 1256 one is completely different. You can fit the OHC victor engine complete,( just further back with the victor sump) but it screws with everything else, so a OHC viva sump is an absolute 'must have', as is the pick up pipe and dipstick.

You will also have to have the exhaust manifold from an OHC viva, no other way about it, these engines are so close to the chassis rail only the proper thing will do.

You will have to have the OHC viva gearbox, the victor one is too short on the tail piece.

You should already have the gearbox tunnel cover plate, it's the same as the OHV one, you just drill out the rivets, spin it round 180 degrees and rivet it back in place.

Now here's the bits you can scrimp on.

The OHV front subframe will work, you either cut off the engine mount brackets and weld on OHC ones ,or you bash them back with a hammer until they far enough back to support the engine in the correct position. You will of course need the correct engine mounting brackets and mounts that are bolted to the engine, but as far as the subframe goes you can tweak it yourself.

Back axle, the OHV one will run a slant, all you will need is to bolt the OHC propshaft up to it and it's ready to go. The pinion bolt flange for the OHV axle and the OHC axle are the same distance from the centre line of the diff, The bigger OHC diff has a short pinion, because its a big old lump, the rather small and weedy looking OHV axle has a long pinion, it's obvious when you see it. And yes the 1256 axle will take most of the stick a standard slant will throw at it, you'll only break it if you do 'traffic light drag strip' type of things, if you drive it normally it will serve you well.

You will also have to swap the brake lines and fuel lines over to the other side of the car as they run too close to the exhaust if you leave them in place.

You don't have to swap the servo, your HC standard one will be fine, but if you don't have a servo....this is still fine, just be prepared to stand on the brakes with a heavy foot.

But to Do It Properly do everything 1972nail says, my way is the 'on a budget' way and even though i did run viva's this way, i did always end up swapping out the axle for a OHC one, the OHV one was just until I got the correct axle... but it does work my way if you wanted it done in a weekend

But on a different note, the 1256 can be fun, you don't have to go through all the trouble of fitting the slant, which is a heavy old lump and lots of trouble at times. The 1256 will take a fair bit of stick, and so will the gearbox, they can be lots of fun,I've had plenty of OHV engines that used to scream Stick a weber twin choke on it and have a bit of fun. The OHV viva can be made to handle superbly without all that weight of a slant upfront.

[HC Fairley]

Quite the juxtaposition here. Never thought I'd see the day when the top IVA enforcer would be telling us how to do things to our vehicles in an improper fashion

[rizzo]

Quite the juxtaposition here. Never thought I'd see the day when the top IVA enforcer would be telling us how to do things to our vehicles in an improper fashion

[Tokyo-Grift]

Thanks for the advice everybody. After reading this I'm looking at crossflow engines! The long short of it is my 1256 has been running funny and unreliability since the say I got it. £250ish later and its still missing slightly, down on power, even though its had a carb rebuild, compression test, valves are good etc. Won't go over 60mph before feeling stressed and also takes a year to get there. So if anybody can let me know in depth how to make a 1256 fun, I would be very grateful. However a nicely tuned 1300 xflow or a standard 1600 xflow is looking rather appealing. I did look at the essex v6 but unreliability seems to be there too! Thanks again all

[HC Fairley]

I often wonder is this a case of rose tinted glasses. I certainly experience the same thing as you Tokyo-Grift, my 1256 will sit on the motorway at 75 if required, 80 if you are really determined, but at that you have the pedal mashed to the floor and are searching for that 5th gear it is begging for. They seem to be at their happiest in top gear bumbling along at 45mph. Not a big fan of hills either, you are either dying in 4th gear or revving the nuts off her in 3rd going up it, there is no in between

From what I can gather there is only so fun a 1256 will get before it goes pop and you are left in a not so fun situation on the side of the road. Id say the starting point is probably the sport part options offered at the time such as Stage 3 head, Stromberg 175CD or Dellorto 45DHLA Carb conversion (some of us have started to fit HIF38 SU carbs from 1275 minis, see last magazine) 4 into 1 exhaust and an electronic ignition.

Even after spending all that time and money you might still be left feeling disappointed and vying for the 2300, i'm not sure as I am still running about in the standard 1256 with the old points ignition in it lol.

[Tokyo-Grift]

See mines never even made it to 70mph, its just not got it in it. I'd be happy with it running 'reliably' and being able to sit at 70mph. I think maybe the 1300 crossflow would be helpful because its already got more punch out the box and there's a huge aftermarket tunablility for them to unlock a few ponies. That being said I've also been offered an essex v6...

[HC Fairley]

Certainly sounds like you have a problem then. You should check your timing and how good your spark is. I am assuming if your carb has been rebuilt and properly set up it is not a fuelling issue you are experiencing.

What are the reliability issues ?

[Tokyo-Grift]

Reliability issues such as the random misfire causing it to stall out occasionally, always runs incredibly hot but the radiator isn't blocked and the water pump is fine. Maybe a good idea would be to put the money into a rebuild if it really can sit at 70mph