3.0 24V into Alfa 75

[Alfamania]

Hey Guys,

I love my 3.0 12V but I am considering a 24V conversion. From what i can see I know that, I will have to relocate the intake on the plennum, fabricate an oil sump, hopefully use the exhaust manifolds from the 24 and weld them on the original exhaust. Just wanted to ask if anybody has done it and if its worth it? Hopefully the engine mounts are the same. Thanks guys

[Neil Choi]

Allan Goodall, long time member and brilliant racer and driver has done it.  He is on the forum sometimes.

From how he drives, it is definitely worth it.

[Victor Lee]

I've had two 24v engines now (3.0 & 3.2), that have been in my Alfetta GTV6.  But Allan is the only I know who has done it in a 75 in Australia.

use the exhaust manifolds from the 24 and weld them on the original exhaust

What's "24"?  The 3.0 12v has round exhausts port. The 24v has oval exhaust ports, and will not fit so new extractors/headers are required.

[ANG156]

EVO75 in melbourne has also done this conversion. You can do a search for his threads on the alfabb.com forum or youtube.

[shiny_car]

Yeah, alfabb.com, alfaromeo75.co.uk, and alfagtv6.com forums are worth having a browse to help your research.

Fitting the engine seems relatively straight forward. If you keep your 12V for parts, you can transfer some of the requirements (bell housing, etc); flywheel spacing needs to be addressed IIRC. Looks like fabrication is required for the alternator and PS pump brackets, and I've yet to confirm that an AC compressor can be fitted without major issues. Love or hate the various intake plenum options, but I'm not a fan of the 'purely cosmetic' appearance of the 24V plenum compared with the 12V. Then a matter of the electronics, brake booster (shape), and repositioning the oil filler cap. Unsure about exhaust manifolds.

What's your estimate on costs? I think it would cost me $5~6K for the conversion, including engine.

I would prefer the 12V with ITBs, but parts alone from a supplier like AHM in the UK would mount to $10K or so, so it would be double the cost.

[aggie57]

Are there not two versions of the 24v or is that the 3.0 vs the 3.2?

[scott.venables]

Are there not two versions of the 24v or is that the 3.0 vs the 3.2?

Yes indeed.  The 164 24v has the same oil pump arrangement as the 12v (auxiliary shaft driven from the cam belt), all later 24v engines- 156 2.5, all 3.2s and 3.0 found in Spider/GTV and 166 have a short internal chain driven from the front of the crankshaft. In the later 24vs the oil pump pick up is in a different position compared to the 12v and early 164 24v.  The long and the short of it is that the RWD sump fits pretty well the early 24v and doesn't fit the later engines without cutting out some baffles in the upper half of the sump and re making the bottom half. 

Many threads on the other forums about it

Scott

[Alfamania]

Thanks Guys for the great response. At this stage I just want to see the requirement for a project like this. I love the look of the 12V motor. I am either looking at upgrading the engine management system on my 12v, or removing the whole motor and replacing it with the 24V one. The Bosch L-Jetronic system is a bit old now...

Cheers

Alex

[scott.venables]

If you don't mind DIY, have a look at Megasquirt fuel injection

[VeeSix]

I have a great 164 24 valve motor available currently 

[105gta]

Hi Alfamania, I'm in the process of a 24v swap myself, the sump is not a real issue, bit of fiddling but easy DIY, to use original 12v sump on 24v, I'm planning on running the full 24v belt arrangement, keep the later ps pump, ac comp and alternator.. No real dramas again just a few lines to move around. Main consideration is type of ecu, the later factory crank signal pick up is on the flywheel, sensor is bolted to sump, your old crank pulley wont fit as the sensor wheel fouls the water pump, easy to make a bracket to use old original sump with new sensor, I'm in the process of designing the spacer plate required for the flywheel to incorporate the crank trigger wheel, happy to share any info with you, engine mounts swap straight over, just need three shorter studs off the old engine for one side...

[Alfamania]

Thanks for the info guys. I just wanted to know what it involves to put a complete 24V engine in my Alfa 75? I wouldnt want to make a greatest hits out of the 12v and 24 V 

Cheers

[Alfamania]

So do you mean that the 24V should go straight in an Alfa 75?

[Anthony Miller]

Alex, a 24v will not just go straight in, all the alfa 24v engines are east/west configuration. To mount one north/south you will need to borrow some bits from your 12v engine as well as swap out the ecu.

[Alfamania]

Ok so this is the way I see it:

Consider the 12V completely removed. I want to put a complete 24V in an Alfa 75:



Can I use 12V or 24V engine mounts for 24v to fit?
Do I need to do anything to 24v Sump to fit in Alfa 75 engine bay? or straight in?
Does the transaxle assembly fit straight on to 24V or do I need to use bits from the 12V?
I know I have to change the location of the plennum intake on the 24v so it fits from the side
Can I use the headers from the 24V and weld onto Alfa 75 exhaust? Will have to remove 12V headers
Why do I have to remove p.steer, air con alternator etc from the 24V? This stuff is already bolted onto the engine and seems there should be room anyway, is that right?

Thanks