Alfa Romeo Owners Club of Australia Forum

Technical => 160 Series (90, 75, 164 Sedans) => Topic started by: AlfaACT on October 29, 2010, 09:43:54 AM

Title: How can ya tell if a 75 is on LSD?
Post by: AlfaACT on October 29, 2010, 09:43:54 AM
Did all 75s come with LSD?
I am looking at an early V6 (2.5l) 75 and would like to know how to confirm that it does, or does not, have LSD.
I am hoping that there are external physical differences that might make it obvious.
Thanks,
Peter.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: wankski on October 29, 2010, 10:10:17 AM
pretty sure it didn't... the 2.0 and 3.0 had it...

the 2.5l would have been the guts of a gtv6...IIRC

the only sure fire way is to jack the wheels and rotate one - see what happens to the other.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: pep105 on October 29, 2010, 01:28:02 PM
Hi Peter
Bottom line is the 2.5 V6 manual from late 86 to 88 was the only 75 without LSD. Externally has no body kit or rear spoiler and has unique interior with tweed (tatty) trim with GTV6 type headrests (without the mesh) and unique intruments.
It could benefit from LSD though I test drove one
a few weeks ago in the wet it was scrambling for traction.
Dirt cheap though and still fun, still kicking myself for not buying it asit sold for a paltry $1575  >:(
LSD was fitted as standard in 88 as part of an update which introduced Twinspark, 3.0 & 2.5 auto
The 2.5 manual was then dropped 
Cheers Pep
Title: Re: How can ya tell if a 75 is on LSD?
Post by: AlfaACT on October 29, 2010, 01:32:12 PM
Thanks guys,
I was hoping that the casings might be different or that there might be markings on them to enable us to distinguish an LSD from a STD. Apparently not :-(
The car in question has had gear box work done and may have had the box swapped - so just wanted to know how to tell.
Cheers,
Peter.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: pep105 on October 29, 2010, 01:41:39 PM
Oops sorry your talking about gearbox Identifaction and there I was explaining model differences.......
A test drive should confirm it
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Anthony Miller on October 29, 2010, 02:55:11 PM
I think a swirly psychadelic paint job would be a give away :P But seriously, driving as Paul and pep have suggested, is probably the best way to tell model type is not a given as my 3.0l has been robbed of it's LSD as a sin of the previous owner(cheapskate barstard). The best combination would be a V6 with a twinnie transaxle, thinking of doing it to mine to realise more horsepower. Good luck Peter and welcome to the world of Box Love
Title: Re: How can ya tell if a 75 is on LSD?
Post by: 75Guy on October 29, 2010, 03:05:11 PM
You can tell by raising them and turning the wheels, but as someone above said find some gravel and give it some power. Or if you are of the bogan persuasion just attempt a burnout.

My 2.5 has a LSD and short ratio gearbox so I can only assume that someone replaced it at some point. Actually, I know for a fact it was replaced I had it up on a hoist and it was kindly pointed out to me that someone hadn't done up a mounting bolt correctly (eeek). Thankfully all the others were...

Title: Re: How can ya tell if a 75 is on LSD?
Post by: AlfaACT on October 29, 2010, 06:32:38 PM
Hey Guys,

"... if you are of the bogan persuasion ... " nah! Sorry.
I'm goin' with the psychadelic paint job but only if its got the matching paisley interior ;-)

Again, thanks for all the advice.
Today I spoke to the service agent who did the gearbox work - verdict is definitely NOT LSD :-(

Cheers,
Peter.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: dehne on October 30, 2010, 10:51:19 AM
my guess is ur talking about the one on ebay, i spoke with the guy and the gearbox had been replace with lsd but did not ask where it came from, would be a good cheap buy that one
Title: Re: How can ya tell if a 75 is on LSD?
Post by: vin sharp on October 30, 2010, 06:18:41 PM
Quote from: 75Guy on October 29, 2010, 03:05:11 PM
You can tell by raising them and turning the wheels, but as someone above said find some gravel and give it some power. Or if you are of the bogan persuasion just attempt a burnout.

My 2.5 has a LSD and short ratio gearbox so I can only assume that someone replaced it at some point. Actually, I know for a fact it was replaced I had it up on a hoist and it was kindly pointed out to me that someone hadn't done up a mounting bolt correctly (eeek). Thankfully all the others were...



You cannot tell a stock LSD or not by raising and turning the wheels; the LSD clutches are engaged by torque input from the pinion opposing the resistance load from the wheels.........ie, there is nothing to 'engage' the wheels together if they are off the ground.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: ARQ164 Shane on January 05, 2011, 04:59:53 PM
g;day all,
So I have an 2.5 QV 1987 not sure if it's got an LSD but I have never spun one wheel it's always two.
And it catchs me unaware at the lights if i take of to quick. I look like a tool as i am not trying to do it deliberatly.

All the best Shane. 
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Storm_X on January 05, 2011, 05:30:25 PM
If you dump your clutch at high revs at both wheels spin and the car kicks out a little, i would guess it has an LSD.

Or if you have a area to test on eg a track you turn the wheel full lock and dump the clutch again at highish revs and is the car spins tightly allmost on the spot it has lsd,but if it does really wide rings and doesnt seem to spin the ass end out its an open wheel diff plus you would see a huge singe line going it circles.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: ARQ164 Shane on January 05, 2011, 09:11:06 PM
hey storm,
All my cars up to this one were open centers , But this little puppy not friendly at high rev's
unless you are on the highway. It loves to rev like a motor bike in 5th gear??? that why i have a shift light on my tacho
keeps trying to push me through the corner in a straight line?? it has heaps of grip and then it lets go and its like driving on black ice.
but that might be the cheap Sims tyres.

what do you think??

Shane
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Storm_X on January 05, 2011, 10:46:36 PM
i would have to see your car if you bring it down to tell
Title: Re: How can ya tell if a 75 is on LSD?
Post by: aggie57 on January 06, 2011, 07:27:21 AM
Just put one wheel on some gravel and the other on tarmac, then accelerate briskly.  If you have an LSD the wheel on gravel will not spin.  If it does you either have an open diff or some very worn clutch plates.  The latter is pretty common.

Alister
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Storm_X on January 06, 2011, 05:54:54 PM
Quote from: aggie57 on January 06, 2011, 07:27:21 AM
Just put one wheel on some gravel and the other on tarmac, then accelerate briskly.  If you have an LSD the wheel on gravel will not spin.  If it does you either have an open diff or some very worn clutch plates.  The latter is pretty common.

Alister

Not a good idea for me. i did it once on my LSD and blew my spider gears
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Sheldon McIntosh on January 06, 2011, 06:11:15 PM
So just to confirm here.  To check if it's got an LSD you shouldn't take the mechanically sympathetic advice of someone who has been racing and working on Alfas for over 30 years.  And instead you should.....

Quote from: Storm_X on January 05, 2011, 05:30:25 PM
dump your clutch at high revs .....turn the wheel full lock and dump the clutch again at highish revs and is the car spins tightly allmost on the spot it has lsd,but if it does really wide rings and doesnt seem to spin the ass end out its an open wheel diff plus you would see a huge singe line going it circles.

Yep, that sounds far more likely to not damage anything.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Storm_X on January 06, 2011, 08:02:25 PM
the diff will blow easier from half on tarmac and half on dirt then then doing a circle in some cases, witch is what i have lernt from experience more then once, plus i know a thew people and have heard stories about wrecking diffs half on tarmac and dirt.(also dumping clutches and circle work)

Either way thrashing the Alfa diff it will blow the spider gears, there weak.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Sheldon McIntosh on January 06, 2011, 11:04:10 PM
Fair enough, I'll defer to you on the topic of destroying diffs, you seem to know what you're talking about.

Title: Re: How can ya tell if a 75 is on LSD?
Post by: aggie57 on January 07, 2011, 07:18:33 AM
Quote from: Storm_X on January 06, 2011, 08:02:25 PM
the diff will blow easier from half on tarmac and half on dirt then then doing a circle in some cases, witch is what i have lernt from experience more then once, plus i know a thew people and have heard stories about wrecking diffs half on tarmac and dirt.(also dumping clutches and circle work)

Either way thrashing the Alfa diff it will blow the spider gears, there weak.

"briskly" Storm, "Briskly".   I didn't mean dump the clutch or circle work.  That's "thrashing".

Alister
Title: Re: How can ya tell if a 75 is on LSD?
Post by: ARQ164 Shane on January 07, 2011, 08:39:19 AM
So all this take about dumping the clutch ( no way ) I think I will ask Lioyd at s.t.a.r.t he rebuild them.
thanks for the input .

all the best
Shane
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Storm_X on January 07, 2011, 10:54:09 AM
Ive destroyed to many diffs in my time for my liking (3), but i am no expert.

Ive seen how people push there Alfa's at the tracks, and they don't drive them like there a brand new grange statesman. Buts there is a difference between track and daily Alfa's.


Any way shane when you jack you car and start it up do both wheels spin? and is it easy to stop the wheel with your foot while spinning in 1st gear? Thants one way i check to get a close guess.
Title: Re: How can ya tell if a 75 is on LSD?
Post by: ARQ164 Shane on January 08, 2011, 08:27:32 PM
If it in the air two spin yes,But isn't it activated by centrifugal forces ?? (thought ) my speedo is crap maybe the tranny.
been swaped out. My car was from QLD ,vic and now S.A . ???

Shane
Title: Re: How can ya tell if a 75 is on LSD?
Post by: Storm_X on January 08, 2011, 11:00:59 PM
take it on the grass and just give it a little and if it slides around like its on ice then its a LSD