Alfa V6 options
Discussion
Howdy friendly folk of Alfa land! I come seeking help and enlightenment. I'm looking at building a kit car with the Alfa V6 in it, but I'm struggling to find info about the engines themselves. I'd probably be looking at the 2.5 12v to start with so I leave myself an nice easy upgrade path to the bigger engines. Now the question is this really, are there any major issues or known faults with any of the various V6's? Do they need any particular treatment at all, or just the usual oil and filter stuff?
Oh, also, any one know how these engines respond to things like new exhaust systems and replacing the inlet stuff with ITB's and so on?
Oh, also, any one know how these engines respond to things like new exhaust systems and replacing the inlet stuff with ITB's and so on?
From what I've been told, when I had issues with mine(top end rebuild as cams had worn due to loose bolts from a mechanic not tightening things back together properly), they're bomb proof.
Seems to be the way so far with mine. She was running for about 30K with the loose top and still pulled like a freight train. Found replacement cams (pretty new too) and got her sorted.
She doesn't drink oil at all - in fact I'm worried she doesn't drink it like everyone claims they do - might be the 108K she has on her mind....
Seems to be the way so far with mine. She was running for about 30K with the loose top and still pulled like a freight train. Found replacement cams (pretty new too) and got her sorted.
She doesn't drink oil at all - in fact I'm worried she doesn't drink it like everyone claims they do - might be the 108K she has on her mind....
I'd echo the above - as long as you basically look after them, I'm not aware of any known issues with the V6s.
I had the 12v 2.5 in my old GTV6, and I've currently got a 12v 3.0 and a 24v 3.0, and I reckon the 2.5 was the nicest, if not the most powerful.
If you're building a kit car you'll know far more about this than me, but bear in mind that the newer engines are transverse so might* be a pain for mounting points, gearbox, etc. if you do decide to upgrade.
*or might not. I don't really know.
edit - for the 3.0 12v I've got a free-er flowing exhaust with no cat, and a chip to suit, and it made a significant difference in the midrange.
I had the 12v 2.5 in my old GTV6, and I've currently got a 12v 3.0 and a 24v 3.0, and I reckon the 2.5 was the nicest, if not the most powerful.
If you're building a kit car you'll know far more about this than me, but bear in mind that the newer engines are transverse so might* be a pain for mounting points, gearbox, etc. if you do decide to upgrade.
*or might not. I don't really know.
edit - for the 3.0 12v I've got a free-er flowing exhaust with no cat, and a chip to suit, and it made a significant difference in the midrange.
Edited by jamieboy on Friday 7th March 13:12
bint said:
She doesn't drink oil at all - in fact I'm worried she doesn't drink it like everyone claims they do - might be the 108K she has on her mind....
My 3.0 24V stopped drinking oil at 8k miles and only used about 2l up to that point. Ever since then (40-odd k later) it's only had oil swaps at service time. 
pdV6 said:
bint said:
She doesn't drink oil at all - in fact I'm worried she doesn't drink it like everyone claims they do - might be the 108K she has on her mind....
My 3.0 24V stopped drinking oil at 8k miles and only used about 2l up to that point. Ever since then (40-odd k later) it's only had oil swaps at service time. mine uses no oil at all
Excellent news folks. Things like mounting points are no real issue as they have a suitable set of holes on each side. Same thing goes for a gearbox, since the engine needs a new one anyway.
So tuning tends to aid the mid range rather than the top end so much? I don't need loads of torque, as the car will only weigh in at 650-700 kgs, but tyres don't cost that much so.........
So tuning tends to aid the mid range rather than the top end so much? I don't need loads of torque, as the car will only weigh in at 650-700 kgs, but tyres don't cost that much so.........
My 3.0l 24v V6 has done 94k miles, burns no oil (the oil does not even get very dirty) and gets driven in a decidedly Italian style. My car has a less restrictive exhaust and it does seem to breathe a bit better at high revs, it revs even more freely than it did and I believe that an induction kit helps a bit more but it is really not necessary as the engine is so good as standard.
What sort of kit are you planning to put it in?
What sort of kit are you planning to put it in?
Snake the Sniper said:
The main issue is the lack of a commercially available bell housing. What is the cam belt interval on the V6? I'd probably go for all new belts anyway, but if it was done 10k ago, for example, then I wouldn't bother.
"Officially" 72k/5y but most folks err on the side of caution with 48k/5y and 60k max.funwithrevs said:
24 valve engines rev higher than 12v.
12v engines can be bought in pre-cat converter 164 donors, on some kits the cat can be a pain as it generates more heat to get rid of.
Excellent, that was going to be a follow up question about the cats. I'd prefer to get an engine that never had them as plumbing is easier as is the emissions test, so what age/model/type would I be looking at for the 2.5 in either 12 or 24v version?12v engines can be bought in pre-cat converter 164 donors, on some kits the cat can be a pain as it generates more heat to get rid of.
I have a 12 valve 3.0 pre-cat V6. There are plenty of cars with these engines in that are heading for the scrappers now or fetching very little money on Ebay. I can heartily recommend them. The 12 valve doesn't rev as high as the 24 valve and doesn't produce as much power (about 185) but they are absolutely indestructible. My engine is 18 years old, has nearly a quarter of a million miles on it, has been dunked in seawater once and gave 154bhp at the wheels on a rolling road last weekend. I've never even had the heads off! To my mind they sound nicer than the 24 valve cars but I agree that if it's not torque you're looking for, the 24 might be a better bet because the 12 valve produces it all lower down and redlines at a surprisingly un-Italian 6000. That said, it pulls all the way up to the redline!
The 12 valve has a much simpler and more durable cam belt arrangement. The 24 valve has 4 cams so if access around the top of the engine bay is restricted, the 12 valve is MUCH easier to package and to replace belts on. The hydraulic cam belt tensioners can leak. A cheap seal kit is available and is easy to fit when the engine is out.
The gearboxes on the early 12 valve 164s were famous for eating their input shaft bearings. Unusually, the input shaft doesn't stick into the back of the flywheel - it stops short so (not surprisingly) there can be a lot of load on it! Worth rebuilding the gearbox before you fit it for this reason alone (if you were going to use a transverse setup). You mention bellhousing adapters so I guess you're going RWD. Just beware there won't be a bearing in the back of the crank though.
The 12 valve engine loom is very easy to disconnect from the rest of the car and the pre-cat one is pretty neat with fewer wires. I think I still have the colour codes somewhere for the ones that you need to provide power to in order to make it go and to work the rev counter.
I don't think there are any significant power gains to be had cheaply on the 12 valve. If you go for the "Cloverleaf" spec, you get about 220bhp and I think that's just cams and a different ECU / plenum / airflow meter but I'm not sure. The 24 valve trick of just fitting bigger intake runners doesn't work on 12 valvers. I think the main company specialising in go-faster bits for that sort of engine is Squadra. I don't have a link but they should be easy enough to find on Google.
God luck with the project - it's a bonnie looking car!
The 12 valve has a much simpler and more durable cam belt arrangement. The 24 valve has 4 cams so if access around the top of the engine bay is restricted, the 12 valve is MUCH easier to package and to replace belts on. The hydraulic cam belt tensioners can leak. A cheap seal kit is available and is easy to fit when the engine is out.
The gearboxes on the early 12 valve 164s were famous for eating their input shaft bearings. Unusually, the input shaft doesn't stick into the back of the flywheel - it stops short so (not surprisingly) there can be a lot of load on it! Worth rebuilding the gearbox before you fit it for this reason alone (if you were going to use a transverse setup). You mention bellhousing adapters so I guess you're going RWD. Just beware there won't be a bearing in the back of the crank though.
The 12 valve engine loom is very easy to disconnect from the rest of the car and the pre-cat one is pretty neat with fewer wires. I think I still have the colour codes somewhere for the ones that you need to provide power to in order to make it go and to work the rev counter.
I don't think there are any significant power gains to be had cheaply on the 12 valve. If you go for the "Cloverleaf" spec, you get about 220bhp and I think that's just cams and a different ECU / plenum / airflow meter but I'm not sure. The 24 valve trick of just fitting bigger intake runners doesn't work on 12 valvers. I think the main company specialising in go-faster bits for that sort of engine is Squadra. I don't have a link but they should be easy enough to find on Google.
God luck with the project - it's a bonnie looking car!
custardkid said:
always wandered why none of the 7 style cars used this wanderful engine.
As mentioned the bellhousing/gearbox situation is a bit of a pig. Most of the RWD V6 installations had a rear transaxle and a de Dion back end which isn't what most Se7en builders want. The fact it's a heavy old lump doesn't help either.
Acocet, which of the 24v engines would you suggest as being most tunable? I'm the kind of person that can't stop tinkering, and engine access won't be an issue, as it can be removed easily if required due to the wide engine bay and RWD set up. I intend going to bike throttle bodies at some point, possibly before the SVA, and if I get really silly, a supercharger too, so things like cam changes are easily accommodated.
Dunno! I've spewed out the sum total of my knowledge on the 24 valvers above!!!! I think they're pretty much all the same internally - again, there was a Cloverleaf version but I imagine that it would be much the same sort of deal as the 12 valve cars - basically the same but different cams, intake runners etc. I think they're quite expensive to tune as they are normally aspirated and pretty good on power output anyway in standard tune. I was wondering about supercharging the 12 valve lump but it's probably just a pipe dream! I gather it's now possible to get superchargers that are centrifugal "fans" rather than "compressors". They seem very small (about the size of an alternator) but I can't remember the name.
If they are the things I'm thinking of, they are basically a belt driven turbo with an epicyclic gearbox so the engine only gets the boost it can actually put up with. I had a feeling the block/heads and so on were a standard part with the cams and ecu being the primary differences. I had heard things about going to the 3.2 GTA inlet cams, but I imagine the TB's and new mapping will make a noticeable difference to the top end.
Anyone know of somewhere on the net, or in a book, that would explain further what things these engine like? I know there are steel rods and so on out there, but I don't know if they're worth the expense.
Anyone know of somewhere on the net, or in a book, that would explain further what things these engine like? I know there are steel rods and so on out there, but I don't know if they're worth the expense.
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