156 3.0 V6 tuning help

Hi all, I'm running a 2.5V6 156 with a 3.0 V6 engine from a GTV. I'm not sure what power it is running at but it is faster than the 2.5. I'm wanting a little bit more power, not sure the best way to go about it.

Everything from the car's air feed before the filter to the engine itself is standard 2.5, including the air flow meter. I think this might be restricting the engine's breathing?

Does anyone know if the air flow meter is the same for a 2.5 and a 3.0?

If I was to remove the current set-up what would be a good alternative to use as in 'bang for buck'? Replace with 3.0 GTV filterbox and pipework from a scrappy is what I'm thinking, but is there a better after market alternative that isn't outrageously expensive?

Car will need to be chipped I think but this will be a bespoke chip and I need to get the air intake sorted out before this is done.

The exhaust has already been upgraded from the cat back.

Thanks,

Dup

Get the GTA intake on there for a start! That 2.5 is too small it will be restricting somewhat.

Not sure about the MAF. But I thought the whole intake was completely different.

What ECU are you running? Is it remapped to suit the 3.0 engine? That will need a tweak. I would do all the other work first though.

Sounds like a nice project car

OA

Best option would be a GTA maf but you'll need to fit a piggyback chip to get the fueling right. I don't think you'll get much of a gain out of it in terms of bang per buck.

Redd ran a 3.0 in his 2.5 and I'm pretty sure he used most of the 2.5 stuff but with a remap. Also 2.5 exhaust manifolds etc although I think I read 3.0 GTV are the biggest.

GTA uses pretty much the same intake parts as 2.5 V6 except the MAF - filter box might be slightly longer as air filter is bigger?

Have thought to put a 3.0 in my V6 but the current engine has only 66k kms so too good to swap at the moment

Originally Posted by OperationAlfa

Get the GTA intake on there for a start! That 2.5 is too small it will be restricting somewhat.

By GTA intake do you mean the pipe from the outside of the car to the unfiltered end of the air filter box? The snorkel? I have one of these from a 3.0 GTV but it is broken. I have searched on the forum, it seems a few members have bought the snorkel from the GTA, is this the intake pipe you talk of?

Originally Posted by OperationAlfa

What ECU are you running? Is it remapped to suit the 3.0 engine? That will need a tweak. I would do all the other work first though.

Its running the ECU from the 2.5 V6, runs fine without any problems, fuel economy is good on a run so I don't think its too rich/lean. Not sure if it has all 220 horses that are in the GTV, although its certainly more than the 190 from the 2.5 V6. Feels a lot torquier. I'm in Leighton Buzzard which isn't far from Watford so will be giving Red Dot a call once the intake is sorted.

Originally Posted by OperationAlfa

Sounds like a nice project car

Thanks

Originally Posted by Chris155

Best option would be a GTA maf but you'll need to fit a piggyback chip to get the fueling right. I don't think you'll get much of a gain out of it in terms of bang per buck.

The car is fitted with a 2.5 MAF but I have a 3.0 MAF, this would be different to the one in the GTA right? I'm not sure if the part numbers are the same for 2.5/3.0 MAFs, I'll have to check.

Originally Posted by Pascs

Redd ran a 3.0 in his 2.5 and I'm pretty sure he used most of the 2.5 stuff but with a remap. Also 2.5 exhaust manifolds etc although I think I read 3.0 GTV are the biggest.

Don't have a clue what manifolds are on, might be the ones from the crashed GTV or from my failed 2.5? Any ideas how I can check? I heard the manifolds from the 164 3.0 Cloverleaf were the best. Also heard you can retrofit the intake runners from the Cloverleaf, they were 230bhp standard weren't they? I'm sure the runners were the reason for the extra ten horses...

Originally Posted by Pascs

GTA uses pretty much the same intake parts as 2.5 V6 except the MAF - filter box might be slightly longer as air filter is bigger?

I'm sure its different, member on here Nicky has done the GTA intake mod on his 2.5 V6, here:

http://www.alfaowner.com/Forum/alfa-...ml#post1372075 (GTA intake on a 2.5V6)

Originally Posted by Pascs

Have thought to put a 3.0 in my V6 but the current engine has only 66k kms so too good to swap at the moment

I think a 3.0 conversion is a good starting point for further modifications. I've heard Autodelta can bore this engine to 3.7 like they can with the GTA, which would be

Git
I'm not jealous
Git

Seriously, ideal mod, theres no substitute for cubic inches as the Yanks say.

A 3.0 would be lovely, its an ideal mod for any 2.5 owner.

Dup, have heard Red Dot are good, so if you do go there you'll be in good hands.

Originally Posted by Dup

By GTA intake do you mean the pipe from the outside of the car to the unfiltered end of the air filter box?
The snorkel? I have one of these from a 3.0 GTV but it is broken. I have searched on the forum, it seems a few members have bought the snorkel from the GTA, is this the intake pipe you talk of?

yes! I'd love to see this car. you should come along to the meets. Any pics?

If that car is running the standard 2.5 map, the air fuel mixture is going to be out - I would say it would be running slightly lean (air for a 3.0, fuel for a 2.5) so yes, it'll seem economical on a run. Take a spark plug out & see if it's a beige-ish colour.

Augusto at Red Dot will sort you out - he should plug in the O2 sensor, which will effectively tell him the Air Fuel ratio (AFR) - he can then tweak the ECU settings to suit.

Best thing would be to give him a call & talk it through with him

Originally Posted by jason156

Git
I'm not jealous
Git

Seriously, ideal mod, theres no substitute for cubic inches as the Yanks say.

Haha, all you need to do is leave your cambelt alone for a while and the opportunity to remove the 2.5 and drop a 3.0 in will arise, trust me

It wasn't even bad value for money, for less than £2000 inc VAT and the remains of my 2.5 I got a 3.0 fitted, with new belts and tensioners, aux belt and tensioners, thermostat, radiator, clutch and 6 platinum sparkplugs. Plus my 2.5 had 95K and the 3.0 from the crashed GTV had only 40K. Well worth it in my mind, Alfa wanted over £3K for a rebuild!

Originally Posted by Pud237

A 3.0 would be lovely, its an ideal mod for any 2.5 owner.

Dup, have heard Red Dot are good, so if you do go there you'll be in good hands.

Thats good to know, thanks.

Originally Posted by OperationAlfa

yes! I'd love to see this car. you should come along to the meets. Any pics?

Very busy with work at the moment and a friend is borrowing the camera, but I'll get some pics up next week sometime I hope

I would say a BMC CDA airbox is the way to go. When my afm failed the new one was invoiced as for a 156 V6 ...

Originally Posted by Paddy2bsure

If that car is running the standard 2.5 map, the air fuel mixture is going to be out - I would say it would be running slightly lean (air for a 3.0, fuel for a 2.5)

That's rubbish. It'll be absolutley perfect provided its running a 2.5 MAF. If anything it'll be slightly rich on 3.0 injectors.

Originally Posted by Chris155

That's rubbish. It'll be absolutley perfect provided its running a 2.5 MAF. If anything it'll be slightly rich on 3.0 injectors.

I would have thought it would be neither rich nor lean, as the 3.0 engine would suck in what air it could through the 2.5 filter/intake and the MAF would measure it, and the ECU would tell injectors to inject the appropriate amount of fuel?

Its a stock 2.5 ECU, stock 2.5 intake set-up with a stock 2.5 MAF...

I've had a bit of a think about this and I reckon GTA cams would be the best solution. Cheap too - I notice you paid someone to fit the engine, I have genuine GTA cam locks and would be willing to do the work...

Originally Posted by Dup

I would have thought it would be neither rich nor lean, as the 3.0 engine would suck in what air it could through the 2.5 filter/intake and the MAF would measure it, and the ECU would tell injectors to inject the appropriate amount of fuel?

Its a stock 2.5 ECU, stock 2.5 intake set-up with a stock 2.5 MAF...

Exactly. The 3.0 has bigger injectors though. Having said that mine is perfect with GTA injectors. (I have an innovate AFM to keep an eye on things)

GTA's run a different MAF. I THINK the sensor itself it the same but the body is a larger diameter. I am not 100% certain though, I think the basic maf electronics are identical but the sensors may be positioned in a longer sensor body so that its central in the gta body....


If that makes sense, I'm not as pished as I think I am.

Originally Posted by Chris155

I've had a bit of a think about this and I reckon GTA cams would be the best solution. Cheap too - I notice you paid someone to fit the engine, I have genuine GTA cam locks and would be willing to do the work...

Hmm, how much would a set of cams cost? Obviously it'd make sense to do belts and tensioners at the same time right?

Originally Posted by Chris155

Exactly. The 3.0 has bigger injectors though. Having said that mine is perfect with GTA injectors. (I have an innovate AFM to keep an eye on things)

What is the engine and ECU in your 156?

Originally Posted by Chris155

GTA's run a different MAF. I THINK the sensor itself it the same but the body is a larger diameter. I am not 100% certain though, I think the basic maf electronics are identical but the sensors may be positioned in a longer sensor body so that its central in the gta body....


If that makes sense, I'm not as pished as I think I am.

I think the 2.5 and 3.0 use same MAF and housing, the 3.2 uses a different housing but the sensor unit is the same.

I've got a 3.0 GTV airbox spare which I intend to fit, maybe with a GSR silicone pipe from the top of it to the throttle body instead of the MAF housing and plastic pipework. Do you know if the snorkel from the 3.2 would attach to the 3.0 airbox from the GTV? My 3.0 snorkel is cracked and damaged, and I know the GTA intake pipe is cheap enough even from a main dealer.

GTA intake cams, apparentley half the price from alfa rather than the autodelta ones (which are just GTA cams)
45mm intake runners - GTV may have this already? GTA certainly does.
Have a look at an airmass from a 164 cloverleaf - these where the larger old style units rather than the modern bosch ones, but the point is the leaf ran 230bhp with little factory modding other than air mass, intake runners and ecu.

A pity its not so easy to fit a 3.0 V6 into a TS - I have a fantastic condition TS which I plan to sell - would be so much more fun to put a 3.0 GTV engine and gearbox into it as all the V6 156 for sale here are junk

Originally Posted by jasons

Have a look at an airmass from a 164 cloverleaf - these where the larger old style units rather than the modern bosch ones,

That won't work!