570 Super RPM's

I'd like to turn the rpm's up a little over stock on my 570 Super.It still has the stock diesel with the AB PSB pump.I use it only for pulling.I've tried just tightening up the external governor spring adjustment to get about 2200 rpm but even this little increase causes it to surge under light load until it needs to get down and pull about 3/4 way down the track.Then it evens out and roars.It does the same on a dyno until it's fully loaded.
Would a stiffer spring and less adjustment help or is this surging the down side I've got to live with.
Any thoughts would be appreciated.

The PSB was built in two speed range versions, under 1900 and over 1900 RPM. The difference was the higher speed models had an extra spring in the pump housing to hold the tappet against the cam for higher RPM. Not sure which one you have, but if it just has the head plunger spring only I'm surprised you're getting it that fast. The military pumps on the 6x6 trucks have what you need. Or better yet, get an IH model 100 pump and get rid of the PSB. I put one on a 570 last summer, runs well but wasn't an easy bolt on. Now he wants a turbo...

also timing changes with higher rpm below 1700 rpm's 24 degrees above 1700 rpm's 28.

Thanks for the info guys.My memory of the rpm's might be a little high.It was last year and it was such a PITA to back off on the throttle to stop the annoying surging until I was under enough load that I backed the spring off to about 1900 or so until the surge was eliminated.I may have maxed at 2200 with the surge under light load.
It sounds like I've got the single spring type pump and since it was recently rebuilt,I'll probably stay with it.
I did advance the timing to 28 when I was trying to run more rpm's but have now returned it to 24 since I've also backed the rpm's back close to stock.
I didn't see any real HP gains on the dyno at ether rpm or timing settings.About 80 is the best I could get with some pump adjusting.
Since I do get plenty of black smoke and I still have a little pump adjustment left,I was also doing some turbo research and am leaning that way.I was thinking one with an adjustable waste gate with just enough boost to clean up the smoke.This engine was freshened up 200 hundred hrs ago and I realize being a non turbo engine,it has plenty of compression so I run the risk of blowing head gaskets with to much turbo.

Any suggestions Dieseltech on the best place to look for a turbo for this 339" Hercules.I was thinking with the limited rpm's I might want to stay on the small side?

For starters you might use a stock AirResearch AC 190-200 turbo. Not too expensive and close to the airflow you need. That turbo would run stock at 15 to 17 PSI by the AC 7000 book I have, engine is 301 cid. Just depends how hot you want to get. The PSB military heads are 9MM, I think yours is 8MM plunger size. If you really want to perk it up it needs the Model 100. At least parts are around for it, unlike the PSB and with the intervance the timing can be set back so it starts much better too.