Alfa Romeo Forums banner

3.0, 164 12/24V into GTV6

9663 Views 77 Replies 15 Participants Last post by  Gabor K.
I posted this in Engine Conversion section too but thought it might get a few more looks here.

Hey there gang! While my 2.5 only has 76,000 miles and runs great I still, of course would love another 40 to 50 hp and am thinking of a 3.0 swap. First off let me say that I don't want a $15,000 or more project nor am I looking for crazy 300+ hp. I'm looking at 200 to 240 max. Also I'm in California so emmisions are a factor. Am I correct in assuming that a 3.0 Milano with say, S cams would get close to 200 hp and with cat and all sensors hooked up pass Cali smog?

What are the pitfalls and benefits of 164 12/24, engine management, coil packs vs dizzy... I know it's a bunch to ask but I know this is the place.

Thanks in advance!
Glenn
1 - 20 of 78 Posts
A 200 horsepower 3.0 is not a tall order. Don't go any hotter that 164S cams and it can get through with no problems, even with L-Jet.

Modern engine management can help with emissions and you will pick up a little power. The big problem here will be the underhood visual inspection. Coil packs will be a dead giveaway the car is modified so don't use them.
Thanks Greg just what I wanted to know.
Hello

Good luck on your project. I am sure no matter what way you go with you will like your Alfa with more HP.

I am almost done with my 3.0L 24V conversion. I really learned alot. Too bad Greg's supercharger will not pass smog in CA. I think this is probably an easier way to get HP.

I will let you know if we pass CA smog. I will let you now about the visual. I have coil packs, etc. My Alfa is going to be tweaked in the next couple of weeks and will be done. I pray that 270 hp at the flywheel is going to make me happy. We set up it for CA smog so well see.:)
Good luck with your E test I hope you pass. In a 2850 lb car I think 270 hp would make me real happy! I have the 4.10 gears so I think 200 for me will be real nice.
Do you think visual inspection will be a problem, I know that 99% of the people in my state don't know what the car is, infact when i went to get it inspected they wrote Alpha on the form.
It all depends on the inspector. When I got my 164L smogged the first time the guy wanted to see my EO (Executive Order) number for the intake runners. He thought they were after market. I'll tell you one thing a 3.0 Milano motor wouldn't give anyone too many probs but a 164 engine looks out of place in an 80's GTV6 in my opinion. Well from an inspection perspective, personally I think they look awesome in the engine bay. One of my good friends from high school owns a smog test only inspection station and I think I'm going to ask him what he would do if he saw something out of place. He owned a general repair shop for many years and is very car savy so he might have a good opinion on this.
2
This 3L 164 12V engine looks pretty ordinary at first glance for a controller. Hard to see its missing a distributor, has big runners, 292 cams and 11:1 CR and over 210 Hp. If you are dependent on having a catalyst, you could install big flow race type and have minimum loss. Also dont think that you have to use the 164 plenum, as you can see here. The runners have the same diameter as the big ones on the 164. So no loss, with original looks.

Attachments

See less See more
Cchan, you will be very happy with 270 horsepower. Your car should really fly.


Regarding the smog checks, it really depends on the inspector. Any decent tech would notice a missing distributor. They would probably also notice the headers (essentially required on a 24 valve conversion). Perhaps they could be hidden with a heat shield...
Headers are OK as long as the O2 sensor is still attached as I have them on my 2.5. I agree an inspector would be pretty dense to believe that there were coil packs on a car of this vintage so that is a sure fire givaway.
Maybe you can just buy my 3.0? I'm thinking of selling it, but not 100% as yet.
Would anybody object that the car had modernised engine management as long as the measurements were OK?
I have heard stories from Germany where there is an aftermarket for installing catalysts on old cars in the ongoing effort of improving the environment. Modern technology is very welcome there! Maybe it will be mandatory to install catalysts here for old cars in the years to come just to be allowed to drive them in the future..
The GTV6 was marketed without catalyst in Europe.
Our cars have cats also but I think the issue is modification. In California they don't like to be confused and if a techician sees something amiss he has the absolute right/obligation to fail you and make you go to the EPA and DOT or CARB and have you prove car is legal. One would think if I put a 24V with upgraded engine management and it lowers emmisions the state would be grateful. One would think!
Maybe you can just buy my 3.0? I'm thinking of selling it, but not 100% as yet.
I have my ears to the ground for a 3.0 but your 1000 miles up the road so it will most likely be down SOCAL way.
That's shouldn't be such a big problem. Shipping is quite cheap. I bought my 24V from Arizona.

Anyway it has JE pistons, CB cams, SZ headers, more details later.
Would anybody object that the car had modernised engine management as long as the measurements were OK?
I have heard stories from Germany where there is an aftermarket for installing catalysts on old cars in the ongoing effort of improving the environment. Modern technology is very welcome there! Maybe it will be mandatory to install catalysts here for old cars in the years to come just to be allowed to drive them in the future..
The GTV6 was marketed without catalyst in Europe.
Gabor K, your 12V looks fantastic. I've been thinking 164S 3.0 with Motronic may be the way to go but a 3.0 Milano engine with S cams may have to be how I end up because of cost reasons.
Gabor, your engine does look great.

It's important to understand that in California the problem is not the engine's actual emissions level. It's the law that states everything under the hood has to be stock, or replaced with a part with a C.A.R.B. number. In the case of engine swaps the rule applies to whatever is newer, the car or the engine.

An Alfa V6 with modern fuel injection will have lower emission than a completely stock engine. However because it's not stock, they don't care.
I'd be weary of going to a 24v - the guys testing may not know alot but they know enough to look specs up in their book. On my last smog, they were very much checking that the timing was where it was supposed to be (I think 2-deg.) and the idle under 1K. Because they couldn't see the mark and were half complaining - It took me two pretests with a nearly new motor that was so clean you could breath from the tail pipe. It blew away all the numbers it was so clean in all the tests except for the 15mph test - I think because the guys just didn't juice it up enough on the throttle to keep the o2 sensor working (even though I drove the crap out of the car and never turned it off before the test). After replacing the o2 sensor it just passed the 15mph test.

If the yearly testing happens someone in another state may well be very lucky to buy my car ... or then again I'll just deal with it each year just to say shove it to the big man!

For me it would be too risky to chance the 24v not passing the visual, also I don't know where the timing is set on the 24v motor but if it isn't at 2-deg. you beter come up with a way to make it "look" like 2-deg!

GV
See less See more
SZ headers really don´t fit on a 24V! , so..?
Hi Gabor,

Who are you referring to? If it's to me, the SZ is on my current 12V. My 24V has custom stainless, TIG welded manifold.
1 - 20 of 78 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top