Transmission info for 24v gtv6 retrofit

[GTV6PASSION]

I am in process of putting a 24v into my 1985 GTV6. The question I have is about the transmission. Is the GTV6 transmission strong enough and good enough for about 240hp. The transmission was rebuilt about 1000 miles ago by the person I purchased it from. Should I leave the GTV6 trans or would it be considered an upgrade to go with a Milano transmission with LSD. And if so which one ? What is the difference between the 3.0 trans and the Verde trans if any. What would be the benifits in going to a Milano trans or stay with what I have. Any held would be grateful.

[slyalfa]

I would say go Milano Verde it has the LSD and tall gears so you will get much better MPG
now if this is only a track car then you might want the hard to get LSD with the low gears.
but I think with the tall Verde box it is stronger as the pinion is larger and that seems to be the part the goes first.
I do not think the old box will be problem other then lack of LSD. but if you use the car every day like I do the gas saved will pay for the tall tranny in a year or so.
and if you had the gears lightend I think you can use the same gears in the new box.
In fact I think you could use the whole gear set if only 1000 miles on it and use the case and diff off the new box.

[nizam]

Quote:

Originally Posted by GTV6PASSION Is the GTV6 transmission strong enough and good enough for about 240hp

[GTV6PASSION]

Thanks so far. the car will be strictly street. What do you mean exactly the the Verde box is the more desireable one. Elaborate Thanks.

[GTV6PASSION]

Are you telling me that I could take a Verde core and use most of my GTV6 transmission parts to rebuild the Verde core with the LSD.

[slyalfa]

yea as far as I know the that will work. I think the only difference is the case and the diff. the ring and pinion. The part for the speedo is eletronic on the Verde.
and I think it is not on the gtv but I think I have read that the part can be moved over from the old tranny but the reading will be off with the different diff ratio.
but most spedo shops can make a small box that will fix that.

[Potenziato]

Quote:

Originally Posted by nizam That said, slyalfa is right in saying the Verde gearbox is more desirable. It has LSD and taller gearing which will help put the power on the ground.

[nizam]

Quote:

Originally Posted by GTV6PASSION Thanks so far. the car will be strictly street.

[Potenziato]

Yeah, I understand your point Nizam. Unfortunatley there is no 6th gear for a Milano. My M3 box is pulling about the same rpm's in 5th as a 4.10 but I can slip into 6th and pull down 500 rpms. If were looking for a good ratio for comfort, I would use 3.73 or 3.92 from a 75. Maybe you could regear a 4.10 and put in a taller 5th gear.

Since the Alfa engines date back to the year one, we get no stinkin VVT on intake and exhaust cams. Variable geometry on the plenum like the Porsche varioram would help too. All these goodies give modern engines much flatter torque and good horsepower at the top.

I still think the 24V is alot softer below 3500 than a bone stock Verde motor. Maybe not quite a dramatic compared to a cammed 12V motor. It's like the difference between VW A2 GTIs. The 8V engines had a lot more midrange torque but the 16V engines breathed alot better at high rpms. I personally loved the 16V but you had to work at it to keep them on cam. You think 3600 rpm at 80 is buzzy, my 16V would pull over 4000 at 80mph. I still miss that damn 16V!

All the 164S, 75 Potenziato, and the SZ used shorter gearing to compensate for torque in the cammed motors.

[GTV6PASSION]

Guys thanks for the input. Since the car will be a street car the Verde trans seems the way that I will go . The question now is do I have the Verde transmission lightened and the LSD increased maybe to 50% . I have had these changes by some people. Is it worth it? What will I gain. Is it worth the Monies. Thanks Sebastian

[5yearplan]

I would definately have the gears lightened if you're already in there, it will help with the rotating mass which is the best way to free up power at the wheels. The 50% LSD is going to lock up faster, if I understand right. So that will depend on the climate. In the snow/mud it will help alot, other than that I'm not sure how well it helps with pulling out of corners and pulling from a stop on the straight aways and what-not. Nobody likes a "one tire fire"

[slyalfa]

as far as I know mine is stock (unless the PO did somthing) and I have never had one tire spin. it is both or nothing. But a bit tighter I guess will not hurt as long as it is not so tight that it keep the car from turning with out skiding a tire.

[Greg Gordon]

Don't forget there is a speedometer issue and depending on exactly when your 85' was built there may be a shift linkage issue. A Verde transaxle into a GTV6 is not terribly complex, but it's far from a plug and play swap. There are quite a few GTV6s out there with Milano transaxles and no working speedometer.

Lightening the gears won't make any measurable amount of difference in rear wheel horsepower. What it will do is extend the syncro life. I do think it's worth it.

[5yearplan]

this may or may not be related: Just out of curiousity, is there any way to convert from the mechanical speed sender to a universal electric one, I'm thinking of putting an electric speedo in my car, and maybe swapping out the tranny, or atleast a few gears and LSD.

[slyalfa]

if you use a universal electric one it should be no problem(with the eletronic Milano sender) . if you use a Verde speedo it comes in 2 parts. the part in the dash and a box under the back seat if memory serves.
and get the whole shifer out of a Milano. there was a good writeup on this bb or on gtv.org
also check out Lsd
it looks here they say the diff can be swaped into the old tranny. I thought the case was different to make room for the extra bits.