What inlet

[waggygsi]

the nova needs a head gasket an was thinking of putting a 1200 carb engine head on it question is what inlet shoukd i run?? cheers:thumb:

[garyc]

1300 nova with a 2e3 or replacement weber.

[pyromaniac_yeti]

If its an SPI engine take into account that just slapping the carb head on the block isnt enough. Part of what makes the carb engine better was a difference in bore/stroke. You'd be better off fitting the whole 1.2 carb engine, which is where my thread came from.

Also note the issues with fuel pressure that have to be got around & the changes to the wiring loom. The carb head runs a different distributor, so that would have to be swapped out too.

If its not a 1.2 engine you're on about then its worth noting that whilst the ports are a better shape, the valves are tiny so you'd probbably see more of a gain from simply reconditioning the current head & having it skimmed to put the CR where the 1.2 would put it (the carb 1.2 has a smaller head volume)

Its all about what you're trying to do really & what you've got.

[waggygsi]

sorry yeah its a 1400 spi but been converted to run a single weber carb this was the engine that was in the car when i bought it

[meritlover]

this will not solve the issue of a blown head gasket! however, iam interested in your theory that increasing VE will overcome gasket leakage and maintain the current performance. This is very clever thinking and i award you with pennies of silver. but please fix the head gasket! the answer is use a 1.2 manifold that matches the head because they are in keeping like a pair. thank you.

[pyromaniac_yeti]

I think the thinking behind it is actually a case of "Okay, heads gotta come off - so lets make any tweaks now whilst i've got the chance." Not that an improved c/r would magicly fix a leaky gasket.

At least i hope not anyway! lol

Given the setup as stated above i realy dont think fitting a 1.2 head would be worthwhile. Think about giving it a skim & popping the appropriate hot cam in though - SR for a carb dizzy & GSi for an injection dizzy (both have different style drives on the end of the cam) Get the valves out & clean them & the head up, set the valve clearances. Should hopefully give you a real noticeable gain if the heads all gunked up! Seems a shame to loose the weber as they were offered as an upgrade! Perhaps find out if its possible to fit a scrappy twinchoke onto the same manifold?

But realy i think you're looking at a new head, inlet manifold, carb & dizzy. And even then i cant see it making any gains! Seems a lot of £££ and effort for bugger all.

[meritlover]

you may struggle with setting the valve clearences with the standard tappets

[pyromaniac_yeti]

If its anything like the TD removing the shims & replacing with thinner/thicker as required shouldnt be too hard. If self ajusting tappets that have failed causing out of spec clearances, replace them. Or on the older pushrods they'll have a screw/locknut adjuster thats far easier to work out. However being an ex injected 1.4? Unlikely.

Either way, out of spec valve clearances are worthwhile checking & sorting whilst the heads off & you can get the cam out.

Is someone feeling a little bitter & sarcastic this evening?? :roll:

[MK999]

Standard tappets on an 8v petrol are hydraulic, so no clearances.

[pyromaniac_yeti]

Same symptoms as iffy valve clearances though if they're on their way out though. Still worth pulling out and having a look at is it not? Myself i'd rather find out that a tappet was on its way whilst it was all in bits than just ignoring the whole lot, chucking em back on and hoping for the best, just to have my time saving come and bite me in the **** a week later when it gets bad enough to start cold rattling.

[mowgli]

meanwhile, back at the thread.......

the 1200 carb head will fit straight on with the 1400 gasket.

if you are woried about tappets, they are so simple to clean up...

as for the manifold, the 1200/1300 heads are nigh on identical and have 'cathedral' ports, which means they have ports shaped like catherdral windows, or for us non religious types, arched tops with a squarer bottom end.. the later manifolds don't usually line up, and you could try to find a 1300 carb manifold as this sounds like the best option, but the 1200 manifold & carb will make the engine run & quite well, but its only a single choke.. the twinchoke will obviously make a bit more power.

what manifold are you using at the moment?

[waggygsi]

this will not solve the issue of a blown head gasket! however, iam interested in your theory that increasing VE will overcome gasket leakage and maintain the current performance. This is very clever thinking and i award you with pennies of silver. but please fix the head gasket! the answer is use a 1.2 manifold that matches the head because they are in keeping like a pair. thank you.

obv I'm going to sort the headgasket you bellend

[waggygsi]

meanwhile, back at the thread.......

the 1200 carb head will fit straight on with the 1400 gasket.

if you are woried about tappets, they are so simple to clean up...

as for the manifold, the 1200/1300 heads are nigh on identical and have 'cathedral' ports, which means they have ports shaped like catherdral windows, or for us non religious types, arched tops with a squarer bottom end.. the later manifolds don't usually line up, and you could try to find a 1300 carb manifold as this sounds like the best option, but the 1200 manifold & carb will make the engine run & quite well, but its only a single choke.. the twinchoke will obviously make a bit more power.

what manifold are you using at the moment?
when i got the car it was a 1600 but changed to a 1400 when the 1600 gave up.
looks like it been an spi manifold with an adapter plate welded on so that the weber carb can go on also looks astho the engine is using the orignal 1.2 dizzy loom an cam box

[mowgli]

are the manifold ports square then?? it might fit, but it won't flow too well

[waggygsi]

aye prots are square lol engines a pile o pish lol so if a used the 1200 head the 1300 sr inlet would be best??

[mowgli]

yes. it will go quite well.

[Leeboo]

When I killed the bottom end in my last Nova 12NV, I fitted a corsa B 1.4 spi bottom end, retaining the 12NV cylinder head, cam, inlet and carburettor.

It made a noticeable difference and definately picked up much better at low revs, however was still a bit strangled at high revs due to the restricted breathing.

1.4 SPi oil pumps can temporarily seize, this happened to mine at 3k rpm after 550 miles and bent valves.