Reverting a low pressure 98 to stock.

[LA.Loic]

I picked up this ugly low pressure 98 custom for its new palmers reg. Now I’d like to run it as a loaner, at 800 psi. But when I ran it as is (no reg, and without the rt) I obviously couldn’t get the fps past 220. I have most of the original parts but I’m not sure how much needs to be changed back. Does the hammer need to be the original? It currently has a very cool rear cocking setup with integrated hammer.
Does the valve have an accessible spring that would require changing? I’m assuming that the main spring needs changing.
I’m just not in the mood to go back and forth trying all of the possibilities. Thanks for any and all information.

[Toestr]

Yes probably the hammer and/or mainspring you need to swap. Is this a homebrew LP mod or does it use the actual kit? Looks like it's missing the volume chamber so I don't really know how 'LP' it will go. If it's the kit you're better off taking all the LP parts out and selling them since they tend to be sought after. I don't know that it would hurt the valve necessarily but it doesn't make sense having them in. The valves have lighter springs, larger air passages, and different stems and seats.

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[LA.Loic]

I’m going to crack the gun open and take close ups of the internals.

[LA.Loic]

Spend quite a bit of time swapping parts on this marker the other day. Plugging up the port for the reactive trigger bumped my fps from 220 to 240. Swapping the original hammer brought it up to 280. Could it be that I'm dealing with a lightened Hammer? I'll take some pictures of the gun's internals soon to give you all a better idea.

[Natural Newbie]

hi loic. im dealing with the same sort of thing. i am converting a "DIY LP" which ran on CO2 (probably in the 600 psi range after the regulator), to run on HPA at 850 psi (output from tank) . By just going from CO2 to HPA, velocity went from 290 to 240ish. by making the reg a pass through (essentially a volumizer), velocity went back up to about 280. after that, replacing the soft LP mainspring with a stock stiffer tippmann spring, brought the velocity up to 300.

One interesting thing, removing the pass through reg from the VA, and installing the tank directly to the VA, velocity dropped 20 fps. This tells me that even HPA at 850 psi needs some sort of a volumizer before the CVX, to get near 300 fps.

I soon will be compiling some data, on how the following items affect velocity:

springs, volumizers (which is also includes the type of tubing used, macro vs braided line, etc), hammer weight, CVX spring, CVX porting paint to barrel match, etc.