Different download speed for wireless and ethernet

[#1]

I have logged my download speeds (using the PN tester) for some years and found that the ethernet and wireless connections gave me very similar speeds (about 6000kbps).
PN have just upgraded me to ADSL2 and my router is syncing at over 14000kbps - great. The speed tester gives me about 11000kbps on the ethernet connection but less than 8000kbps by wireless.  These data are obtained with the same computer, so I seem to be hitting some limit on the wireless link.  Has anybody any ideas on what needs to be tweaked to improve the wireless speeds.
My configuration is a Netgear DG834 modem router connected to a Belkin 54g wireless router set up as an access point.  For these tests the PC was next to the access point, connected at 54Mbps wireless.  The ethernet speed is the same if I connect to the access point or the modem router or if I use another PC.  I get 16Mbps when I do a file transfer by WLAN and 100Mbps for file transfer by ethernet LAN (about the maximum to be expected).

[#2]

54Mb wireless never gives anything like 54Mb on real world throughput, even if you sit your PC right next to the router there's transmission overheads, security overheads etc., if you're any distance away or have any interference then the performance degrades further - the truth is WiFi speeds are possibly the only thing more 'oversold' then broadband speeds.
Either get a long ethernet cable or invest in a good quality 'N 150' or , preferably, 'N300' router (and matching adaptor for the PC) - or sit closer to the router!!

[#3]

The 54mbps specification is arrived at by adding the upstream and downstream speeds together so it's never is 54mbps download speeds. The maximum you see, which you have, is 17mbps.  Also bear in mind the Wifi connection speed decrease the further you are from the access point. From my experience the PC still report the connection speed as 54mbps but this may not be the true speed. On the PC that I'm using to post this it report a speed of 54mbps but if I look at the WiFi access point it reporting 36mbps.

[#4]

Thanks for your prompt response(s).
I know I can't get 54Mbps on 802.11g, that's why I report 16Mbps for file transfer (which, as the second reply says, is all I can expect).  The broadband speed is much less than that at 11Mbps, so its not the wireless protocol that's limiting.  I'm trying to pin down why the wireless link runs slower with a broadband data feed than with a file transfer across the LAN.
To walker,  I think you can see that I have a choice of ethernet and wireless - that's not the point at issue.  Off topic for this thread, if you can really get better performance from an N router I would like to see the data.  There are many discussions on other forums about the disappointing performance of 802.11n.

[#5]

The specified data rates for g are 6, 9, 12, 18, 24, 36, 48, 54, but I have seen mine connection as low as 1 and 2. So it suggest if your throughput was only 8 the data rate may have been 24 or 36 at the time of the test. The data rate is dynamic so can be changing can you actually see what data rate you are connecting at?

[#6]

look at this iSSID plot near me the N routers hog bandwidth and poke out more also look at the max rate column  mine is the top 54, then 150 and 270M

[#7]

As these are maximum and not actual speeds it just informing which technology being used ie. b,g,n

[#8]

To itsme reply #4
Yes, I know my connection is running at 54Mbps, I know that LAN feed  runs at 16Mbps, I know that a WAN feed runs at 8Mbps.  If I change to 100Mbps ethernet, the LAN feed runs at 100Mbps and the WAN feed at 11Mbps (on any configuration of three PCs on the LAN).   The WAN feeds (11Mbps) are well within the limits of the wireless protocol (16Mbps).