Logo

Volvo penta 290 dp

Alf275

New member
Hi guys I have a Volvo 290 dp out drive 2.30 ratio I need 1.78 ratio to connect to a Volvo kamd42p(230hp) do I have to change the upper gear or the lower unit gear? Thanksssss in advance
 
It's all in the lower unit.
Just do a search on ebay for "Volvo Penta 290 lower unit" ,
it will show lower units with different ratios listed.
Any future Volvo Penta questions will get better results if you post
in that forum , it is an active forum with lots of knowledge.
 
There's one exception to this....... and that would be the "E" drive!
Look at your PZNR tag on your transmission, and see if it lists "E".

The "E" transmission gear reduction is greater than all standard ratio transmissions.

For example...... with the "E" drive, a 1.78:1 lower unit gives us a total reduction that's close to 1.95:1.




.
 
thanks RICARDO for your answer I Really appreciate it thanks
There's one exception to this....... and that would be the "E" drive!
Look at your PZNR tag on your transmission, and see if it lists "E".

The "E" transmission gear reduction is greater than all standard ratio transmissions.

For example...... with the "E" drive, a 1.78:1 lower unit gives us a total reduction that's close to 1.95:1.




.
 
I'm intrigued by the "E" drive. What engine(s) would that have came with?
It is a 290? What lower unit ratio(s) came with the "E" ? What years?
Thanks
 
I'm intrigued by the "E" drive. What engine(s) would that have came with?
It is a 290? What lower unit ratio(s) came with the "E" ? What years?
Thanks

The E drive was a Diesel Engine drive...... and was a later series from the 290 series.
The E transmission further reduces the reduction so that a different combination of lower gear sets could be used.

Here's the deal with I/O lower unit gear sets:

The further the reduction, the smaller the "drive" gear ("pinion" gear in the Auto world), and the larger the "driven" gear ("ring" gear in the Auto world).
As the reduction becomes greater, there is less gear tooth contact at any given time.
This equates to a weaker gear set that is more prone to breaking under heavy loads.

So...... in order to accomplish an over-all ratio of let's say 2.30:1 (the 2.30:1 lower gear set being the weakest), the E transmission is used with a 1.95:1 lower gear set (a stronger gear set).
This combination gives an over-all reduction of 2.30:1, or very close to it.

Likewise, in order to accomplish an over-all ratio of let's say 1.95:1, the E transmission is used with a 1.78:1 lower gear set (a much stronger gear set).
This combination gives an over-all reduction of 1.95:1, or very close to it.

In order to accomplish an over-all 1.78:1 reduction, the E transmission would not be used.


.
 
Last edited:
Back
Top