Alfa Romeo Owners Club of Australia Forum

Technical => 160 Series (90, 75, 164 Sedans) => Topic started by: Bone356 on February 18, 2013, 04:24:56 PM

Title: Alfa 75
Post by: Bone356 on February 18, 2013, 04:24:56 PM
Hi guys,

Looking at getting a second car as we don't need the 2 good cars any more (modern) and I have always been a fan of the 75 series so looking at a 2.5 or 3 litre, So......are they a daily driver with kids? i.e. the air-con is it effective working with Melbourne temperatures and power steering light enough for the wife? Can you get baby seats in there as well? Look forward to discussing, cheers Simon
Title: Re: Alfa 75
Post by: aggie57 on February 18, 2013, 04:58:08 PM
We've done the baby seat thing in a 75.  The reverse facing ones are pretty tight by memory, and getting a pram into the boot can be a hassle as the boot opening is a not large.

As far as aircon is concerned they cope fine with Melbourne weather.  There are of course no vents in the back though.
Title: Re: Alfa 75
Post by: Bone356 on February 18, 2013, 09:15:32 PM
Also do the rear seats fold down, split system etc?
Title: Re: Alfa 75
Post by: hammer on February 18, 2013, 09:28:19 PM
Bone,

No folding seats in the 75s. Power steering is nice and light for your wife's parking. No cup holders for her takeaway coffee though mate!

I've had a 3.0 and a 2.0 and loved them both.

Cheers,

Brent
Title: Re: Alfa 75
Post by: Evan Bottcher on February 18, 2013, 09:34:24 PM
I love our 75 twin spark.  The air con in ours is marginal, but it used to be better - probably need to track down a leak and get it recharged.  It has much better air delivery than the 156 we had before, bigger vents - but as Alister points out, no vents to the rear.  Don't expect it to be like a japanese car.

No split fold, not even a ski tunnel.  Power steering is superb.

Strongly suggest you go and have a drive of one soon - shocking to say but they're almost a classic now, last of the rear drive Alfa sedans, such a nice car to drive.  But a modern classic with power steering, intermittent wipers, power windows...

Title: Re: Alfa 75
Post by: Bone356 on February 19, 2013, 09:45:00 AM
So the big question is 2.5 or 3 litre and which model, ie what do you get any leather options? or sport seats etc...cheers for the reply s so far, shame no folding seat! On the alfetta GTV I used just take the take the rear seat out when I needed to carry some equipment, as for a while it was the biggest car we had in the garage, with a Sprite IIIA and porsche 911 73 RS clone....gee days before kids!! thanks Simon
Title: Re: Alfa 75
Post by: VeeSix on February 19, 2013, 10:00:45 AM
They are cheap enough now, go for the best, Alfa Romeo 75 Potenziata V6 3.0 with sunroof, good power, LSD and nice interior if you find one in un sun damaged  condition :)
Title: Re: Alfa 75
Post by: aggie57 on February 19, 2013, 10:12:57 AM
One word of caution - believe later ones had the larger US fuel tank which gives you a decent range but robs the boot of lots of space.  May be relevant if its a family runabout.
Title: Re: Alfa 75
Post by: Anthony Miller on February 19, 2013, 10:52:19 AM
3.0l has the tank in the boot which does make it a bit of a squeeze for the pram but all worth the effort for the extra torque, help save these great cars from becoming donors for 116 gtvs. Very very rare  Recaro leather option, later models(post 1990) have motronic and darker interior with very comfortable standard seats.
Title: Re: Alfa 75
Post by: Bone356 on February 19, 2013, 11:47:52 AM
So how do you know if its a Alfa Romeo 75 Potenziata V6 3.0, carsales has few 3.0 litre so what is the difference?
Title: Re: Alfa 75
Post by: scott.venables on February 19, 2013, 01:07:00 PM
In short, the Potenziata uses the later and more advanced Bosch Motronic fuel injection (earlier V6s used Bosch L-Jetronic) A Potenziata also has slightly warmer cams. You can pick Motronic because they have a toothed ring on the crank pulley where the L-Jet cars have none.

Here's a more comprehensive read about it:
http://www.alfaclubvic.org.au/forum/index.php?topic=8450.0 (http://www.alfaclubvic.org.au/forum/index.php?topic=8450.0)

Scott
Title: Re: Alfa 75
Post by: Duk on February 19, 2013, 08:06:33 PM
For me, the best thing about the Potenziata is the slightly shorter 3.73:1 diff ratio. Not as ridiculously short as having a 4.11:1 TS diff ratio (it's a 3 litre 6 FCOL ::) ) and not as tall as the 3.55:1 of the pre-Potenziata 3 litre V6s.
I've not driven a pre-Potenziata 3 litre V6s, but my guess is that given they actually have similar quoted power, depending on who you want to listen too, any real acceleration improvement will be from the better (lower, but not too low) diff ratio.
Though the Motronic engine management system was leaps and bounds better than the old L Jetronic, it's nothing to get excited about (it was a very long way from being cutting edge in 1990).

1 thing I will say, is that I was not impressed by the standard brakes!
It will depend on what you are use to driving and my other cars at the time both had minor brake upgrades and weighed less, but the standard and definitely not top condition, but far from run into the ground, brakes never inspired confidence in me.
My recently acquired standard 1994 Falcon ute is more reassuring in the brake department than my Potenziata's brakes were.
Title: Re: Alfa 75
Post by: shiny_car on February 19, 2013, 08:24:03 PM
Quote from: VeeSix on February 19, 2013, 10:00:45 AM
They are cheap enough now, go for the best, Alfa Romeo 75 Potenziata V6 3.0

I would say the prices have already bottomed-out on 75s. I like to keep an eye on the market. Potenziata's dipped down to about $4~5K a few years ago, but are now asking more like $7K...and presumably with higher km's. Of course, you negotiate as best you can.

This is the only one on carsales at the moment: http://www.carsales.com.au/private/details/alfa-romeo-alfa-75-1991-14201228

200K+ km's seems par for the course. Anything 150K and under is pretty rare (at least for those ones on sale).

The earliest Potenziata's were build in late 1989; as such most that you see for sale will be 1990+ models. The one above is only the second one I've seen for sale in 2 years, IIRC. Performance-wise, as mentioned it has newer electronic ignition, hotter cams, higher compression, and a shorter diff ratio; the combination of slightly more power and shorter diff equates to brisker off-the-line performance. I've not driven one to know if it's a genuine seat-of-the-pants improvement, but it presumably is. Original wheels are 15" rather than 14".

There's many cosmetic minor details, including rear spoiler, bumpers, and interior gauges/backlighting.

Good luck with the search. You'll likely find the 'better' ones being sold through these forums. Not to say the carsales ones will be poor, but few seem appealing to me.

This one belongs to an AROCA member, and is worth considering: http://www.carsales.com.au/private/details/alfa-romeo-alfa-75-1989-13747467

:)
Title: Re: Alfa 75
Post by: Bone356 on February 20, 2013, 10:52:29 AM
The Grey one was the one I was thinking about, so as a rule of thumb, If it has been serviced at the correct intervals, what is the life expectancy of the 3 litre engine? i.e. if I buy the grey Potenziata with 200K on it when will I realistically be doing a engine rebuild?
Title: Re: Alfa 75
Post by: shiny_car on February 20, 2013, 09:29:54 PM
Pretty hard to say. Probably won't need a bottom end crank bearing change. But the crankshaft seals front/rear may be weaping oil and these are typically an engine-out job.

In the heads, the camshaft seals may be weaping oil. Can be done when the cambelt is next changed.

Probably worth having the clearances checked and adjusted for the camshaft tappets. The intake tappets have shims, meaning the camshafts need to be removed to physically remove the tappets and shims, if the shims need changing for different thickness. The exhaust tappets can be easily changed via a screw adjustment. Mind you, these are only important for extracting the best performance, rather than a reliability issue.

There's a lot of debate about the cambelt OE-spec 'hydraulic detensioner' vs an aftermarket 'mechanical' spring loaded tensioner vs fixed. The hydraulic detensioner is prone to leaking oil, and a little fiddly to overhaul, but I personally think they are a piece of engineering beauty! Leaking oil is obviously a woeful problem, but the functionality is very elegant. Others believe a metal spring loaded mechanical tensioner makes far better sense in terms of reliability and longevity; but only if fitted properly (failure rate goes up considerably if not tensioned properly, from what I've read). I'd say stick with whatever the car has; if it's the original detensioner, have it overhauled (kits available from the US and easy to obtain); if it's a mechanical one, then go with that again. Both work perfectly fine when they actually work!

'How far' you go with overhauling the car is up to you. If there are original wear-and-tear parts, they are likely worn. This includes suspension bushings, shock absorbers, propeller shaft donuts and centre mount, engine mounts, and gearbox mounts.

Worn second gear synchro is a classical 'issue'. Many people live with it, rather than go the expense of having the gearbox removed and stripped.

I've spent a lot of time researching and learning about the 3.0 75s from scratch. It's been an enjoyable process, but it won't be for many people. It's ok for me because it is a project car, and I can spend as long as I want to overhaul the whole thing, top to tail. You are obviously in a different position, wanting to rely on the car from Day 1 as primary or secondary transport, so you probably can't afford to have the car off the road for long periods. And if you're not much of a DIY tinkerer, it can be expensive and a hassle to take the car to a workshop to be fixed.

Definitely have any potential car inspected by a specialist Alfa 75 mechanic who knows these cars inside and out.

:)
Title: Re: Alfa 75
Post by: Bone356 on February 21, 2013, 09:55:08 AM
Thanks guys, good info thank you! Yep any Alfa I buy will always get the Hugh evaluation before parting with cash. So now to sell the Sti and once I have monies in the hand I'll make a decision, my only worry is size factor.
Title: Re: Alfa 75
Post by: Joe Falcone on February 22, 2013, 11:32:53 PM
Hi Simon
owned quite e few of these cars and am a big fan of the 2.0 litre twin spark as a daily drive family car. Grunt, air con, fuel tank size and refined interior are the trade offs but economy and the huge boot might win you over. The sixes tend to develop leaks, can get smoky and use engine oil.
The twin spark is a lot lighter and better balanced too, the sixes are nose heavy. Either way id never sit on the fence and get a 2.5. And finally just for the record the twin spark is more fun to throw around the track and in standard form times are the same too. Not sure how much of this is relevant to your situation but recommend you have a close look at a twin spark before making your purchase.
Ciao Joe
Title: Re: Alfa 75
Post by: Joe Falcone on February 22, 2013, 11:39:47 PM
forgot to mention no cambelt to worry about
Title: Re: Alfa 75
Post by: Duk on February 23, 2013, 08:46:23 AM
While obviously getting a bit off topic, I think adding a well sized turbo to the TS engine would make the car an excellent all round machine.
Grunt and drivability in a better balanced package. It would never sing the V6 engine's song, though.

Just a few notes on the balance between the 4 and later V6's.
Most will know that the impact absorbing bumper bars are quite heavy (17.5kg's from memory) and these are going to have a very negative effect on the turn in response of the car, because they act like the proverbial lead tipped arrow. IE: You can't get that weight any further forward.
Secondly, the 4's and 6's used the same torsion bars sizes: 22.8mm. So while Alfa Romeo were adding more and more weight, they never added anymore spring rate to the car, so the V6's, especially the 3 litres (the 2.5's didn't have the impact absorbing 'bars) are effectively softer sprung than the 4's. The V6's have a lower natural frequency for their front suspension than the 4's.
So adding more spring rate to the front suspension and removing weight from the very front of the car (lighter 'bars and moving the battery to the boot) will help bring the balance difference between the 4's and the V6's much closer together.
There are quite a few things that can be done to improve the front suspensions behavior, but some people like standard cars and some people like modified cars.
Title: Re: Alfa 75
Post by: redsky on February 23, 2013, 11:28:04 PM
Whichever 75 you get i'm sure you won't regret it if you find the right car. I've been wrapped with the Twin Spark i got a couple of years ago.  Comfortable, nimble, quick, great exhaust note and cold air con. Very economical too, yet fun at track days.
The most unexpected & practical aspect to the car is the 500 litre boot. Just amazing for a car this size.
Never thought I'd have an Alfa, but glad I do now. Have fun shopping for the 75.

Cheers Darren
Title: Re: Alfa 75
Post by: Bone356 on February 24, 2013, 09:15:48 AM
Again thank you, for all your comments positive stuff, If I do go down the Alfa route I think it will be a 3 litre just because it's a V6 and I haven't had one before!
Title: Re: Alfa 75
Post by: Evan Bottcher on February 24, 2013, 09:33:07 AM
That is a _very_ good reason.