Your best bet is a Prometheus M100.

Great, thanks.
I'll keep my eyes open for one of those.

Please help
I recently bought a guarder sp 110 and 120 to upgrade my guns to 360 and 420 fps respectively. When I got them though, they didn't feel any stiffer than my stock m90, and when I put the sp 110 in, it didn't shoot as hard either. The 120 might aid this, but it certainly doesn't feel much stiffer. I noticed that the 120 has 35 coils while the 110 had 29.
this is my first upgrade. I realize my air seal might not be perfect, but this sort of behavior is very unusual.
also, just so that you all know, the spring guide, bushings, piston head, cylinder, and sears have been upgraded sufficiently.
please help.

A G&P 8mm gearbox 150% power has how much FPS?

Anyone?

Could the springs have been mislabeled? It isn't uncommon..... If you look at the spring chart it says this as a note after testing:

However the fact that you have a different number of coils makes it seem like that might not be the case. Do you have another gun to test the springs in maybe? Also how are you testing the new speed? If you're doing the coke can test that's not a good test at all, and if you're using a "visual" guess that's also not very good either. You should really use a proper chrono or at least doing the poor mans microphone chrono.

@Behnken: I have no clue, and searching google doesn't give me any info but I would assume that if they offer a 90% gearbox that's designed for CQB and therefore probably around the 330 mark. So my guess based on that is that you're probably looking at the 400-420 mark with a "150% gearbox" (just my guess based on the info given, this is not to be used as actual advice).

When G&P says ins it's gearbox "Power 150%" is how much FPS? And 150% of what??

Cheers

i belive its vs a stock TM spring. that being 100 (.99 joule)
I have a few tms and stock they run around 270
so if you figure 50% more power
270 + 50% = 405 FPS
just an edgeumacted guess
so L4s statement of around 400 should be spot on

That's a problem.

Because in some GB 150% like SP150, M150 and others... it is like 500/550FPS.

That's almost a round-house kick.

IMO, some companies refer to % compared to 1Joule spring, while others (Like Systema) I believe is the actual value in Meters/second, so a M120 systema would go about 120m/s, which is about 400fps if I remember correctly.

SP150, M150, and MS150SP ratings are NOT a percentage rating. They typically refer to 150mps, or 492fps. That looks about right, if you're saying these kick out around 500fps.

Yeah, that's the question.

With value G&P uses?
150% of 1joule?
150% = M150/SP150...


Because there's a big gap between them.
;S

Sorry, couldn't tell you for certain, as I've never used G&P springs before. But if it says "%", it's almost always safe to assume that it's of 1J.

I need a little help please i recently installed an m125 into a AIM TOP M4 with a 300mm inner barrel. My hope was to get around 400-410 fps, i ended up with 330fps. As a result i tried a Prometheus m110 and got 340-344 fps. My air seals are 100% no air loss and the flow coming out of the gearbox seems to be on the dot. can anybody give through me a ball as to what the problem might be?

You have an airleak somewhere. If you didn't have one it would right where it should be at 380-390 with a Prom M110SP.