3.0 swap into GTV6

[martym00se72]

Hi,
getting prices for work on the 2.5 in my GTV6 and for the money thinking that I can likely get a 3.0. It is a well trodden upgrade path - where do people get their 3.0's from in Australia? It is (if it happens) going to be my first engine swap so wanting the 12v as a more straight forward swap rather than the 24v and will be fine (street only use) for me... Also posted in buy/swap/sell in case someone has a spare sitting on their garage floor...
Cheers
Marty

[Anthony Miller]

a 3.0l from a 75 will more or less drop straight in, from a 164 or 156 will require some dicking about changing the orientation

[martym00se72]

Thanks - I will shoot for a 3.0 from a 75 then!

[aggie57]

156's never came with a 3.0 - either 2.5 or 3.2 (GTA).

[Anthony Miller]

156's never came with a 3.0 - either 2.5 or 3.2 (GTA).

Correct , my bad

[martym00se72]

Found one. Getting it. What should I do to it? Engine history unknown other than coming from a wrecked 75, engine was running. It's from an early one so pretty much plug n play if I want or it could be "tweaked' before going into the car. Looking for strong low to mid rev range torque. Have been told I should look at opening out ports and collectors/bowls and bigger cams. Thoughs? Cam recommendations? street use only so no high lift cams etc...

[BradGTV]

jim k's book is a great read with the info you are after

[Duk]

Found one. Getting it. What should I do to it? Engine history unknown other than coming from a wrecked 75, engine was running. It's from an early one so pretty much plug n play if I want or it could be "tweaked' before going into the car. Looking for strong low to mid rev range torque. Have been told I should look at opening out ports and collectors/bowls and bigger cams. Thoughs? Cam recommendations? street use only so no high lift cams etc...

Jim K's book is an obvious choice.
Another is to look at http://www.oldtunnel.com/. It's aimed at the 2.5 litre but the basics are there.
If you follow Richard Jemmison's (Alfa7) writings on the AlfaBB, he is very adamant about the importance of valve seat work and valve shaping. That and cams,  Richard is passionate about cams.
All of that is largely wasted without a proper means to tune your new weapon, so unless you also plan to add a programmable computer to run the show, I wouldn't be getting too carried away with work.

[aggie57]

You say the engine is from an early 75 - so its definitely a 3.0?  Early 75's in Aus were all 2.5.

But as an example of what can be done, years ago a standard 2.5, with cleaned up ports and opened up intake runners carefully matched to the head gave up 10-12 HP at the wheels.  Standard injection, standard bottom end, standard valves. That's within a couple of hp of what a standard 3.0 gives over a standard 2.5. 

[Jekyll and Hyde]

Looking for strong low to mid rev range torque.

You've already got it...  Ever driven a GTV6 with a 3 liter before (3 liter 75 doesn't count, the diff ratio kills a lot of the shove in the back)?  The increase in low down torque over a 2.5 is very surprising, more than you would expect from only half a liter more displacement.  Yes, you could play with the ports and cams, which will improve horsepower, but the increase in 'around town' torque isn't likely to be that great...

I'd suggest putting it in the car as a standard motor, and drive it.  You can always pull the heads later if you do want more...  Although, of course, if you are getting the heads reconditioned before you fit the motor in, that IS the ideal time to do some porting.  Cams can quite easily be fitted later on...

[martym00se72]

I am buying sight unseen but have been assured it is a 3.0 in good nick. Appreciate the considerations. I have not driven a GTV6 with a 3.0 so I am inclined to slot it in and see what it is like as I prefer the car out of the garage and on the road!
Cheers
Marty

[aggie57]

Sounds like a plan Marty. You'll be amazed at the difference and given youre starting with a 3.0 it  really is pretty much a plug and play job.

Do make sure you get all the hang on items though. The 3.0 flywheel and starter etc are different to a 2.5 so you'll need that. There are well trodden paths to deal with those types of things but if you don't need to then....👍

[martym00se72]

Thanks Aggie - are there any other differences like plenum, bell housing, plumbing etc? I'm kinda making decisions on the fly -like getting the 3.0 because it presented itself, but trying to put a bit of a plan around it as I go... I know it is a well trodden path so fell pretty sure that most issues have been confronted previously. Is there much point to looking at getting the lightened flywheel from Performatek (or other supplier??) - this would be the time to put it on I guess...

Duk, thanks for the oldtunnel link - looks very interesting. Might see what I can do with the 2.5 when it is out. Needs new head gasket anyway so heads will be coming off...
Cheers
Marty

[aggie57]

No problem.  I'm on the road and time poor this week, but start by searching on alfabb.com for "3 liter GTV6".  You'll get a good few hits, like this one:

http://www.alfabb.com/bb/forums/alfetta-gtv6-1975-1986/188408-my-gtv6-now-has-3-liter.html