ALFAGTV6.COM

in case anyone else needs to know. 3litre crank pulley bolts straight up, no balance issues, sweet as a nut. Getting the old pulley off is a ball ache though, especially being a cast piece, its brittle. without a puller forget it

mjr wrote: no balance issues

How do you know that? It's unlikely you would be able to feel vibrations that are potentially harmful from the driver seat...

I spoke to a 75/gtv6 specialist in the UK first, who advised me that they have done loads of gtv6 power steering conversions using the 3 litre crank pulley, and have never had any issues. apparently the very late 85 GTV6's that came with power steering option, used the the 3 litre pulley anyway.

Each crank pulley is balanced differently. You can't just swap a pulley from one engine to another and expect to retain the original balancing. Even if it's the exact same type, it's machined to be balanced for each individual engine.

I have no doubt that you can do it, but it's going to throw off the balancing.

I think the late 85' and 86' GTV6s came with the Milano type crank pulley which has the power steering belt slot.

Just have a good balancing shop balance the original pulley to " zero" and then copy the imbalance to the other pulley. That's the way to go with the flywheel too if you don't want to take the engine apart.

thanks for the info greg. as I say the alfa garage say they have never had any issues, but Im thinking perhaps I should be cautious actually. for the sake of not a lot of money to do what evo2 recommends, I think ill get that done. Is that a safe method to use?

yes mine being an 83, doesn't have the milano crank pulley, which was annoying.

Giuliettaevo2 wrote:Just have a good balancing shop balance the original pulley to " zero" and then copy the imbalance to the other pulley. That's the way to go with the flywheel too if you don't want to take the engine apart.

That will certainly work.

Greg

when i change to 24v the steeringrack will also be exchanged for a powered unit, luckily the 24v comes prepared

Very fun and good conversion! When I shoot my steering rack to bits this might be a good conversion for my luxury salon-car.

This thread is worthless with more pictures

Melvivio wrote:
This thread is worthless with more pictures

i hope you mean without...

ahem.... yes I did.....

Damn... Messed that up...

Giuliettaevo2 wrote:Just have a good balancing shop balance the original pulley to " zero" and then copy the imbalance to the other pulley. That's the way to go with the flywheel too if you don't want to take the engine apart.

We can argue about this for a pretty long time I bet but my answer to that method is always going to be: Sure, you can do that but it won't be correct. It will be correct for the speed that the balancing machine you use run at but it can be seriously bad at other speeds.

But if it works for you, do it.

You care to explain that to this simple mechanic?

To me it's like balancing a wheel, you use a certain amount of weight to get the balance at 'zero' the speed at which the balancing takes place doesn't alter this as far as i know off.

I won't argue with you about it, that's for sure ... You do/did this kind of stuff professionally so i'll probably loose the argument.

How about my next engine;
- 3.0 24v engineblock and heads.
- 3.0 24v pistons and rods.
- 2.5 12v Sei crank.
- 2.5 Sei flywheel.
- ? pulley.

I was planning on using a 164 3.0 12v pulley and get that balanced to the same specs as the Sei pulley. This will not work out to be good if i read your comment coorrect. How to go at it then?

If balance is "out" dynamically and you add or remove weight to correct it it will be balanced at one speed, not all speeds. On a wheel it will be good enough since it's not really rotating too fast and there are all kinds of bushings to isolate the small remaining imbalance.

(M*V^2)/2 and all that...

But how to counter that then?