What blocks to get for my H18

Hi guys what setup should i do for my H18??
6:1 or 7:1??
Rachet? on both top and bottom? only bottom?
What is the objective of a rachetting block? make it easyer to hold the line when uncleated correct?

Rachmatic , rachet? what would you get?

Also what mainsheet would you recomend and why?
3/8" or 7/16"

Theser are some recomended options by my dealer

1) 6:1 - 3/8" mainsheet
lower: HAR 2141 - $175.85 US
or HAR 2630 - $240.20 US
upper: HAR 2604 - $114.30 US

2) 7:1 - 3/8" mainsheet
lower: HAR 2141- $175.85 + HAR 2636 - $22.80 US installed on the 2141 becket.
or HAR 2632 - $257.30 US
upper: HAR 2605 - $120.25 US

3) 6:1 - 7/16" mainsheet
lower: HAR 2686 - $310.20 US
upper: HAR 2664 - $166.90 US

4) 7:1 - 7/16" mainsheet
lower: HAR 2687 - $349.65 US
upper: HAR 2665 - $176.85 US

Thanks!

My H18 came with a good setup. I'm not sure of the part numbers, but they are all Harken. I have a 7:1 setup and the lower block only has the ratchet. This ratio is a good balance between the amount force needed to sheet in and the amount of line.

Get the ratcheting block. On a long gusty day you will be very glad you did. You are correct in saying that is helps hold the sail without cleating. Well worth the money.

_________________
Nick

Current Boat
In the market
Previous boats owned
'74 Pearson 30
'84 H16
'82 H18 Magnum
St. Louis, MO

I run a 8:1 system I removed from my Fox before selling it. It has the ratchet on the lower which I would recommend. Don't see a need for racheting upper blocks.