HI, i have an Ibanez GRG 170 been laying around for about 3 years and i wanted to do it up a bit as it is pointless selling it because its in bits. I know it is a basic guitar but with abit of work to it i recon it could be a good started guitar for my brother as he wants to start learning guitar and it be great for teaching him. The problem i can remember with it was that it always kept going out of tune and so i got an Ibanez S470 which i love. Is there away i could out a fixed bridge on it or just a better bridge to keep it in tune, i have already changed the pickups on it and out some warpigs on there.

many thanks
You could order a hard tail bridge from Ibanez. But if you're looking to put a Floyd Rose in there, it just wouldn't be cost effective.
My Gear

Ibanez S470DX
Squier Strat
Washburn Bass

Spider III 15W
Peavey Vypyr 75

Assuming it's a strat style bridge (it looks like one in the pics I've found but I really don't know the guitar) get a Wilkinson Tremelo for it.

Assuming you are in Norfolk, UK, check out axesrus, they have the Wilkinson bridges, with the key measurements so you can work out which one you need.

I've been trying to get tuning stability for ages, and I've tried all sorts of things, but the wilkinson bridge is by far the best upgrade I've come across.