Unless you are going to spin it over 8000rpm on a regular basis, the stock springs have been proven over and over again to be able to be up to it. Its a much much bigger job to change springs than it is to change cams. Even with the head off, its a bigger job and on the car, unless you've done it several times, its a big job that can quickly bit you in the ass, as well as requiring specail tools.
As well, unless you can find a set of those fairly rare cams mentioned above a set of 91-94 TSi cams will be an improvement in power over 3000rpm.
Its not in my sig, but I have a 91 N/T AWD 5spd Galant as a daily driver.
I have done a stealthy cold air package, 92 TSi "C"/"D" cams, a 2.4 Spyder header and a full 2.25" mandrel bent exhaust. The car pulls much harder up top than stock and it also now has a useful powerband of between 3k and 6k rmp, whereas stock it had from about 3200-3800 of useful torque.
With a set of TSi cams(not '90 cams) and a set of cam seals and valve cover gasket you are looking at what? $75? I'd say this is worth it.
Well, unless you are going to be building an uberbeast of course, but then you should be using quality aftermarket cams that are made for N/T engines anyways.
Either seach car-part.com or get new ones from Mitsu. About $175-195 each. Ricart Automotive
Search for 1994 Galant GS. The cams can make power up to 6750rpm on a 2L, but on my Galant it is limit to 6500 rev limiter.
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