tried asking in the other forum, do you have to get an uprated converter or anything when doing basic power mods(exhaust extractors, cam) and also do you have to get a cam that is for gas?

Depends how far you are going but if you are doing basic mods as you say, no, you dont need another converter etc, but I would recommend a re-tune. I have JMM streetfighter head, Crow cam and JMM "race" header+ zorst with a Gasresearch system, and I am still using the same converter etc.

I am assuming that you are doing an I6, and I can tell you that NOBODY makes a gas cam for them. They all say that if you use their "petrol" cam, it will be suitable. This is a load of crap, as gas is a different fuel.

All you can do in this case is make your choice and pay your money. I, as I said previously, have a Crow cam (xan't remember the numbers). It seems to work quite well, and JMM were very surprised when I told them what I had after they had tuned the engine. I am getting 133 kw on the dyno.