the 3k kit is alot cheaper also.
And there have been many Statements that with the 4k kit your vavles may float .
with a 3k kit in my brother truck he can get 3500 PRm fairly easily I suppose ... . I DONT KNOW FOR SURE but with the 4k kit is would be possible to run in the 4500 rpm range witch is BIG TIMIMING IT for a street diesel
Here are some prices for 3k Kits
PDR2613000
Governor Spring Kit 3000 RPM
$125. 00
http://piersdiesel.com/DodgeUSPrice.htm
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Governor Springs
Governor Spring Kit
Increase the governor RPM cut-off with a 3000 RPM Governor Spring Kit.
Price: $125. 00
http://www.tstproducts.com/browsepr...Spring-Kit.HTML
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GSK3 3000 RPM GOVERNOR SPRING KIT $150. 00
http://www.dieseltrans.com/dodge/price_list.htm
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1040187 Dodge 5. 9 12 V Governor Spring kit 3000 rpm $156. 75
http://www.cyclonediesel.com/bdpowerpricelist.htm
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Governor Spring Kit(3000rpm) - $105. 00
http://www.smokindiesel.com/dodge/1...ve_fueling.html
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Governor Spring Kit 3000 RPM PDR2613000 $175. 00
http://jandhperformance.net/Price%20sheet.pdf#search='Governor%20Spring%20Kit'
HUH ???? PIERS SPRINGS THROUGH A SUPPIER LETS ADD $50
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1040187 Governor Spring Kit 3000 rpm P7100 Pump Dodge 165. 00
http://store.bd-power.com/ram/produ...rnor+Kit&tt=ram
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2613000
Governor Spring Kit 3000 RPM
$155. 02
http://www.tadiesel.com/pricedodge.asp
Note I got the ones from Smokin Diesel but it was a typo on there website ... ... they let me have them for that price but they may be more now . .
Most of the above are just PDR springs period so your best bet is to contact PDR for a set of springs
Good Luck
DM