Alfa Romeo 156 2.5 V6
Discussion
You've got an absolutely lovely Alfa there, I've always liked the 156 but I've never actually owned one yet. I say yet because I'm on my 6th currently, after owning a 147ts, 147GTA, 145QV, 155ts, 75 turbo and currently my 90v6.
I've always heard that the 2.5 24v is a sweet sweet engine, revs better than a 3.2 and sounds better apparently. I did own the bigger brother 3.2 and adored the engine, if anything I miss the engine more than the actual car!! I do recommend trying a 3.2 at some point, but it'll be different in character to your motor.
I've always heard that the 2.5 24v is a sweet sweet engine, revs better than a 3.2 and sounds better apparently. I did own the bigger brother 3.2 and adored the engine, if anything I miss the engine more than the actual car!! I do recommend trying a 3.2 at some point, but it'll be different in character to your motor.
davebem said:
A few serial Alfa owners have commented the 2.5 is more characterful. I havent tried a 3.2, it must be an animal as the 2.5 is quick enough.. Maybe the 3.0 is the best allrounder?
I haven't tried a 3.2 so can't comment on that, but the 2.5 is just a sweeter thing. It just has that extra hunger for the red line, the 3 litre doesn't have, in my opinion. I think they are both masterpieces.Absolutely top knick 156 you've got there, they are getting harder to find nowadays in that condition.
I've got the GTA version myself and absolutely love it, the V6 is such a charismatic engine and just has to be revved at any opportunity.
I'll look forward to any other updates you've got for us.
Sam
I've got the GTA version myself and absolutely love it, the V6 is such a charismatic engine and just has to be revved at any opportunity.
I'll look forward to any other updates you've got for us.
Sam
^That GTA is the tits. Ive been driving the car on and off the last few weeks, had a great drive to the east coast and back. Was going to do Rockingham trackday but had to change plans at the last minute, will get my act together and book something at the end of June.
The coolant tank was leaking slightly, and looked a mess inside so ordered a new Birth one.
On draining the coolant I discovered that a small amount of oil was mixed with it, and there was a build of gunk in the tank, a quick search on the Alfa forums and the general consensus is 'all the V6s do that'. Ive fully flushed the system and put in fresh coolant (all 9 litres of it!) and will monitor it.
The coolant tank was leaking slightly, and looked a mess inside so ordered a new Birth one.
On draining the coolant I discovered that a small amount of oil was mixed with it, and there was a build of gunk in the tank, a quick search on the Alfa forums and the general consensus is 'all the V6s do that'. Ive fully flushed the system and put in fresh coolant (all 9 litres of it!) and will monitor it.
Edited by davebem on Wednesday 15th June 21:33
Edited by davebem on Wednesday 15th June 21:34
On a few really great runs in the warmer weather the coolant temp issues I had earlier returned, where it sits at just over 90 (up to 99) whilst on move but with hard driving. Maybe its an OCD of mine, but Im refusing to believe the general Alfisti view this is normal.
I put on hold the 3.0/3.2 air-oil cooler conversion idea mentioned in an earlier update, Ive made a note of what needs to be done:
- Relocation of the power steering cooler to left hand side - easy
- Removing branch from near the thermostat housing to heat exchanger - easy
- Blank return hole from heat exchanger to block - easy
- Fitting of pipes from rear engine to front right hand side and mounting of oil cooler - easy
- and crucially replacing the take off plate at the back of the engine behind the oil filter. Ive had a good look at this and think the engine will need to come out, some of the bolts are not reachable, and the take off plate doubles up as the mid-driveshaft mounting!
After more research I found that the 3.2 GTA has a thicker superior radiator, with a more efficient fin design with twice as many rows (approx 40). The 2.5 probably needs this superior radiator more than the 3.2, because the coolant also has to cool the oil as shown above. I tried to source one and can now understand why many 3.2 owners fit the 2.5 rad as the latter is more easily available and cheaper. The original Valeo part which was out of stock in most places and local fiat/alfa dealer was quoting around £380!! I found 1 cheaper alternative from a company called NRF for a good price at less than half that on eBay and took the risk (assuming this was the only available pattern part). Possibly by sheer luck this turned up in a Valeo box, and the new radiator had Valeo stamped onto it with genuine part numbers!! So I drained the coolant (again) and got it fitted.
Im not sure what Alfa were thinking when they designed the cooling fan assembly, the part looks like it may have been borrowed from a Sherman tank. Its too heavy and over engineered, a lot of unnessary weight in the nose here, and the twin fan motors are huge! Something to consider as there are many aftermarket lighter/plastic fans available.
Finally, my pads were worn from a couple of track days and hard use. I took advantage of the autolusso sale and ordered some PFC Carbon metallic pads. I was concerned when they came as they don’t appear to have as much friction material on as the standard pads (Id say approx 20% less thickness and slightly less area coverage on the pad too!!)
Anyway (somehow) the PFC pads have vastly improved stopping power, you can really feel them dig in on high speed braking and they have improved pedal feel somewhat. They also produce less dust and work well from cold.
Nearly forgot to mention..the superior radiator has worked, had a long run down to Wellingborough and the temps didn’t go over 90 once, success!!
The last item on my shopping list is sourcing a stiffer rear anti roll bar, then Im mostly done, Promise!!
I put on hold the 3.0/3.2 air-oil cooler conversion idea mentioned in an earlier update, Ive made a note of what needs to be done:
- Relocation of the power steering cooler to left hand side - easy
- Removing branch from near the thermostat housing to heat exchanger - easy
- Blank return hole from heat exchanger to block - easy
- Fitting of pipes from rear engine to front right hand side and mounting of oil cooler - easy
- and crucially replacing the take off plate at the back of the engine behind the oil filter. Ive had a good look at this and think the engine will need to come out, some of the bolts are not reachable, and the take off plate doubles up as the mid-driveshaft mounting!
After more research I found that the 3.2 GTA has a thicker superior radiator, with a more efficient fin design with twice as many rows (approx 40). The 2.5 probably needs this superior radiator more than the 3.2, because the coolant also has to cool the oil as shown above. I tried to source one and can now understand why many 3.2 owners fit the 2.5 rad as the latter is more easily available and cheaper. The original Valeo part which was out of stock in most places and local fiat/alfa dealer was quoting around £380!! I found 1 cheaper alternative from a company called NRF for a good price at less than half that on eBay and took the risk (assuming this was the only available pattern part). Possibly by sheer luck this turned up in a Valeo box, and the new radiator had Valeo stamped onto it with genuine part numbers!! So I drained the coolant (again) and got it fitted.
Im not sure what Alfa were thinking when they designed the cooling fan assembly, the part looks like it may have been borrowed from a Sherman tank. Its too heavy and over engineered, a lot of unnessary weight in the nose here, and the twin fan motors are huge! Something to consider as there are many aftermarket lighter/plastic fans available.
Finally, my pads were worn from a couple of track days and hard use. I took advantage of the autolusso sale and ordered some PFC Carbon metallic pads. I was concerned when they came as they don’t appear to have as much friction material on as the standard pads (Id say approx 20% less thickness and slightly less area coverage on the pad too!!)
Anyway (somehow) the PFC pads have vastly improved stopping power, you can really feel them dig in on high speed braking and they have improved pedal feel somewhat. They also produce less dust and work well from cold.
Nearly forgot to mention..the superior radiator has worked, had a long run down to Wellingborough and the temps didn’t go over 90 once, success!!
The last item on my shopping list is sourcing a stiffer rear anti roll bar, then Im mostly done, Promise!!
Edited by davebem on Tuesday 5th July 20:58
The radiator thing is odd.
A while back, the thermostat in my 2.5 failed, and it ran cold when on the move, even in high summer. So the standard rad has enough capacity to cool the engine. That car runs at an indicated 85C or so, which drifts up to 95 in traffic, at which point the fans cut in.
My GT 3.2 is running a bog standard Valeo, and sits at an indicated 90, regardless of outside temperature or traffic.'
My GTA Shed-Wagon is running a standard Valeo (replaced last weekend) and like the 2.5, sits at about 85, going 90-something when the fans kick in.
Yes, the fan assembly is bonkers heavy, though on the plus side, doesn't corrode badly,
A while back, the thermostat in my 2.5 failed, and it ran cold when on the move, even in high summer. So the standard rad has enough capacity to cool the engine. That car runs at an indicated 85C or so, which drifts up to 95 in traffic, at which point the fans cut in.
My GT 3.2 is running a bog standard Valeo, and sits at an indicated 90, regardless of outside temperature or traffic.'
My GTA Shed-Wagon is running a standard Valeo (replaced last weekend) and like the 2.5, sits at about 85, going 90-something when the fans kick in.
Yes, the fan assembly is bonkers heavy, though on the plus side, doesn't corrode badly,
It is a strange problem and all too common by the looks of it, I beleive the earlier 2.5s had copper radiators which may have been more efficient? The car will have a hard life, but will be maitained regardless of cost, its more a reliability modification and peace of mind for me, I just wish I took a picture of the rads side by side!!
Alfa got the handling on these wrong for the factory. I don't know what they were thinking, but it was neither firm or soft, understeered badly. and my V6 bottomed out from new when pushed hard on lumpy roads.
A couple of mm thicker ARBs, especially at the back, sorts out the understeer. As noted by the OP, the Quaife diff transforms the cornering. Decent springs and shocks round it off.
My fleet is configured as follows:
- 156 V6 - all the mods, quaife, eibach ARBs and springs, B6 shocks. Handles like it is on rails, the only limit on cornering is my ability to stay in the driver's seat
- GT 3.2 - bog standard suspension. Slower point to point than the 2.5 above. Very funny in a straight line, not up to scratch in the corners.
- GTA 3.2 - halfway house, rear Eibach arb, Eibach springs, Koni FSDs. Closer to the 2.5, I think dropping the front subframe and sticking in a Quaife will make it perfect, the grunt of the 3.2 combined with the quaife will make cornering a lot of fun, and the seats are more supportive....
Unless they are being looked after properly, pretty much every 156 out there has knackered suspension.
A couple of mm thicker ARBs, especially at the back, sorts out the understeer. As noted by the OP, the Quaife diff transforms the cornering. Decent springs and shocks round it off.
My fleet is configured as follows:
- 156 V6 - all the mods, quaife, eibach ARBs and springs, B6 shocks. Handles like it is on rails, the only limit on cornering is my ability to stay in the driver's seat
- GT 3.2 - bog standard suspension. Slower point to point than the 2.5 above. Very funny in a straight line, not up to scratch in the corners.
- GTA 3.2 - halfway house, rear Eibach arb, Eibach springs, Koni FSDs. Closer to the 2.5, I think dropping the front subframe and sticking in a Quaife will make it perfect, the grunt of the 3.2 combined with the quaife will make cornering a lot of fun, and the seats are more supportive....
Unless they are being looked after properly, pretty much every 156 out there has knackered suspension.
Most 156s seem to have bouncy castle suspension, the sport pack 3s and later Veloces like mine had 'sport suspension' which is slightly lower and has different alignment settings. I actually like the ride and handling! (hence why I havnt done much to the suspension yet), its very comfortable and copes with undulating roads very well. Big bumps are soaked up, and all wheels are kept planted firmly on the ground at all times, the handling is still precise and when throwing it into a corner feels like a hot hatch, except under power it does understeer but out of the corner there is no torque steer. On the odd occasion in wet there I have felt what is best described as a drifting sensation as the rear kind of follows itself round a tight corner. Im at a crossroads now, as I don’t want to loose this nice road feel and character, but if I continue with track use, it really needs stiffening and roll reducing from the back which will hopefully reduce the understeer.
The gear change, clutch feel and steering feel are all still spot on, infact it has made me realise that this puts most modern cars to shame in this area (my 159 included). Like my previous clio172 the 156 is one of those rare cars where you can just take it for a drive for no reason and enjoy the experience for what it is, (whilst forgetting iffy interior build quality and mpg).
The gear change, clutch feel and steering feel are all still spot on, infact it has made me realise that this puts most modern cars to shame in this area (my 159 included). Like my previous clio172 the 156 is one of those rare cars where you can just take it for a drive for no reason and enjoy the experience for what it is, (whilst forgetting iffy interior build quality and mpg).
noway said:
Had my 156v6 for 6 years and its used as my daily, far from mint but its been very reliable...
Crap stock brakes (fixed that) and doesnt handle all that well imo (even with suspension refresh) not particularly quick but still a nice place to be...
soon for sale and will be missed..
Let us know when it goes up. Haven't seen a decent 2.5 since the OP bought this one!Crap stock brakes (fixed that) and doesnt handle all that well imo (even with suspension refresh) not particularly quick but still a nice place to be...
soon for sale and will be missed..
I finally tracked down a stiffer rear anti roll bar, after speaking to a few experienced with 156s this should reduce the understeer somewhat, I will feedback on this later.
The eibach set retails at £350, and the ultra racing standalone rear is £180. I was lucky to find the no longer in production Whiteline roll bar 2nd hand via ebay for a third of that, the Whiteline one looks identical to the Eibach.
The standard Alfa 156 2.5 rear roll bar is 14mm
Summary of otions for 156:
The GTA one is 17mm
The eibach/whiteline is 18mm
Ultra racing is 19mm
Im in the process of rubbing it down, coating in bilt hamber rust proofer, then a quick re-spray before its fitted to the uprated droplinks I fitted earlier.
Side by side with original
The eibach set retails at £350, and the ultra racing standalone rear is £180. I was lucky to find the no longer in production Whiteline roll bar 2nd hand via ebay for a third of that, the Whiteline one looks identical to the Eibach.
The standard Alfa 156 2.5 rear roll bar is 14mm
Summary of otions for 156:
The GTA one is 17mm
The eibach/whiteline is 18mm
Ultra racing is 19mm
Im in the process of rubbing it down, coating in bilt hamber rust proofer, then a quick re-spray before its fitted to the uprated droplinks I fitted earlier.
Side by side with original
Edited by davebem on Wednesday 17th August 20:07
Edited by davebem on Wednesday 17th August 21:31
Before the next trackday I wanted to improve engine breathing.
When I had my Clio 172, I experimented with many differnt setups, various airbox designs, and size/location of air feed pipes. ITG oil type filters are ok but they are messy and a pain to clean and maintain as they get clogged, the K&N cotton filters great when new but again a pain to release the dirt (I didnt find the sprays that effective). I found that the standard paper element filters allowed for just as much free flowing air, and can be thrown in the bin when dirty and cheap to replace. I also learnt the filter must not suck in warm air from engine bay and ideally the air should be as cool and have a short route as possible to the filter.
The filter element in the car looked quite restrictive (the pink one shown below). I replaced it with another better designed free flowing paper element filter from eurocarparts for £5.98.
The Clio 172 has its airbox on the top of the engine bay, I routed bigger twin air feed pipes to the grilles under the headlights, this worked very well and due to the position of the grilles did not let any water in.
I wanted to do something similar for the 156, however the airbox is located at the bottom of the engine bay on n/s in front of the wheelarch, its not a bad location as its a cool area of the bay. Its let down by the air feed pipe that bends and changes direction as it routes up at an angle to headlight level by acting as a kind of water snorkel due to low location. It also constantly changes diameter, starts at 80mm, and goes down to 55mm in places.
I will try running with this pipe removed on the next run, there is some cold indirect air flow going to the box from the grill next to the foglight, and also directly through the main grille to the front closed area of the filter as my car is missing some plastic trim next to the radiator.
This setup will be dangerous in the wet!! So watch this space for a winter solution.
When I had my Clio 172, I experimented with many differnt setups, various airbox designs, and size/location of air feed pipes. ITG oil type filters are ok but they are messy and a pain to clean and maintain as they get clogged, the K&N cotton filters great when new but again a pain to release the dirt (I didnt find the sprays that effective). I found that the standard paper element filters allowed for just as much free flowing air, and can be thrown in the bin when dirty and cheap to replace. I also learnt the filter must not suck in warm air from engine bay and ideally the air should be as cool and have a short route as possible to the filter.
The filter element in the car looked quite restrictive (the pink one shown below). I replaced it with another better designed free flowing paper element filter from eurocarparts for £5.98.
The Clio 172 has its airbox on the top of the engine bay, I routed bigger twin air feed pipes to the grilles under the headlights, this worked very well and due to the position of the grilles did not let any water in.
I wanted to do something similar for the 156, however the airbox is located at the bottom of the engine bay on n/s in front of the wheelarch, its not a bad location as its a cool area of the bay. Its let down by the air feed pipe that bends and changes direction as it routes up at an angle to headlight level by acting as a kind of water snorkel due to low location. It also constantly changes diameter, starts at 80mm, and goes down to 55mm in places.
I will try running with this pipe removed on the next run, there is some cold indirect air flow going to the box from the grill next to the foglight, and also directly through the main grille to the front closed area of the filter as my car is missing some plastic trim next to the radiator.
This setup will be dangerous in the wet!! So watch this space for a winter solution.
I went to Rockingham to put the car through its paces. First trackday where I thought what the hell and was really pushing the car to the end of its limits. I struggled with the chicane onto the banked curve, it was only in the last few mins of the day I realised its better to take it wide and head to the top of the wall and then turn left. I loved running up onto the armcos, but on some of the corners I found gearing was an issue, in 2nd Id hit the limiter, but in 3rd it seemed too low revs to get any power down, which was the opposite to when I did Mallory as the gearing really suited that track. The brakes were performing well, engine temps all behaved, although the heat was getting to me this time I came off every 15-20mins as was sweating like a pig too much in the warm summers evening!! One of the less forgiving issues with the early 156s is poor ventilation, the blowers are rubbish, even with the aircon on max fan speed you cant feel much air through the vents.
The rear roll bar has made a notable difference, hard cornering is improved in general, and coming out of corners under power is much better. The surface at Rockingham is very abrasive, on the last session I could smell burning rubber, my front tyres were starting to fall apart, there was melted rubber in my wheel arch and stuck to back wheels. I did a quick inspection before driving home, tyres were on approx 2mm, I didnt realise until I got home the inside tread on the o/s front was gone and on the n/s parts of the tread had flew off!!
To continue with fast track use, the car will need better lower, stiffer suspension. As you can see from the pics the car dives and leans too much now grip has improved. Also Im pretty sure the body flexes under extreme hard cornering (you can hear the doors creak on the rubber seals!). I think a strut brace at the top of the rear suspension turrets will help a lot. But firstly Im going to source some new tyres/spare wheels to get back on the road!
The rear roll bar has made a notable difference, hard cornering is improved in general, and coming out of corners under power is much better. The surface at Rockingham is very abrasive, on the last session I could smell burning rubber, my front tyres were starting to fall apart, there was melted rubber in my wheel arch and stuck to back wheels. I did a quick inspection before driving home, tyres were on approx 2mm, I didnt realise until I got home the inside tread on the o/s front was gone and on the n/s parts of the tread had flew off!!
To continue with fast track use, the car will need better lower, stiffer suspension. As you can see from the pics the car dives and leans too much now grip has improved. Also Im pretty sure the body flexes under extreme hard cornering (you can hear the doors creak on the rubber seals!). I think a strut brace at the top of the rear suspension turrets will help a lot. But firstly Im going to source some new tyres/spare wheels to get back on the road!
Called into my local rolling road last night as was curious what power I was getting running completely standard and wanted an indicator how healthy the engine was at 88k miles before considering any further modifications. My 2.5 is the later 4X mini cat 192hp cf3 version, only mods was the temp removal of the airbox intake pipe.
The others were getting pretty accurate figures, I got an impressive 204bhp 167ft on the 2nd run. Has anyone else put theirs on a rolling road, do they produce a bit more power than they are supposed to? Maybe it was overeading slightly or mine has been remapped?
The others were getting pretty accurate figures, I got an impressive 204bhp 167ft on the 2nd run. Has anyone else put theirs on a rolling road, do they produce a bit more power than they are supposed to? Maybe it was overeading slightly or mine has been remapped?
Edited by davebem on Saturday 17th September 12:36
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