ALFAGTV6.COM

[darryl longley]

I have read a lot about the twin spark 75 box being the best box to put in the gtv6
I am about to change my original 2.5 engine to a 3.0l and i am now thinkin should i change my gearbox as well
I have a spare taller 1984 gearbox (According to the chart below)

MPH per 1000 rpms Rpms at 60 mph
[ in 5th gear ]

1981 21.78 2,750
1982 26.14 2,300
1983 26.14 2,300
1984 26.99 2,200
1985 22.17 2,700
1986 21.78 2,750

The question i would like to ask is if i was to put in a milano 3.0 gearbox would my 2.5 clutch assembley bolt straight on(it has the milano single plate anyway)
I have read that the twin sparks cluth and yoke assembly are different does this apply to the 3.0 box aswell I know i will have to change the selector shaft to a splined type (origianl on my gtv)
The reason for my question is i have chance of buying either type of box 3.0 or twin spark but both come without the cluch assembly so im thinkin if the 3.0 needs no mods then i may be bettter buying that
So to sum up
should i go with
the original "tall box
the 3.0
or the twin spark
Again neither has a clutch

Thanks in advance

[Mats]

You can switch around the GB/clutch assemblies as far as I know but you need the pilot tube for the throw-our bearing. That is different between at least the 4cyl and 6cyl cars (and probably the dual plate 6cyl but you don't have that as I understand it).
Output flanges for the halfshafts are different but you know that right?

A pic to show you the differences between the TS and 3.0 box.
Redline set to 6300rpm.

[darryl longley]

luckily I have both types of drive shaft flanges as the last gtv6 i had was an 86 (which i had to break due to rust issues) and the flanges are interchangeable from box to box .The small and lghter flanges which where used on the iso box just mean the use of the longer half shafts.
the iso gtv6 box on post 85-86 cars was also used on very early 2.5 75s

[sh0rtlife]

just take your clutch assembly section , the "slide shaft" that the throwout bearing rides on and swap them over to whatever box you want to use......if useing a TS box you will need to swap over 3 studs for your clutch slave mount..and the output shafts but thats all of 8 hex bolts

and of course the shift rod iso vs "normal"

other than that...you may or may not have a speedo sensor issue as the later boxes all use a HEP(hall effect pickup) and the gtv6's use a gear drive

buy an SGI-5 from dakota digital and it will solve your problems...75$ well spent

<just did a TS box into my gtv6 and love it to death

[Mats]

Surely it's a VR sensor?