[JC]

JMO - are you talking I6 or V8? I'll assume I6.

There are so many threads on each of these topics, that your best bet to find all the info you need is to use the search function.

Now, I can summarise it all for you, but others will no doubt post their opinions as well, so you will still need to do the search anyway, I reckon. Here goes:

1. (a) For extractors, Pacemaker 4499s or 4480s will both do the job admirably. The 4499s are better for a stockish engine, while the 4480s give better gains on a mild/wild build. I went the 4499s (on 2 AUs), and would again. 4499s fitted go for between $500 and $700 depending on what town/city you live in. Ring around and get prices.

Power increase anywhere from 5 to 15 rwkw (usually 5)

1 (b) Cats - the stock cat when widened out to 2.5" entry and exit does a very good job - no need to replace it unless it is stuffed. If in doubt, I'd replace it anyway with a 2.5" metalcat or similar from ebay for around the $200 mark. The exhaust place I go to does a 2.5" cat for $200 fitted, as long as you get it at the same time as either extractors, or cats back system (ie no extra labour charge).

No real power increase, unless your current cat is stuffed.

1 (c). Cats back system is what dictates the noise level of your car, as it is the thing that has the mufflers, resonators and/or hotdogs. Personally, (and again, I have this on my current EL, as well as 2 previous AUs) the Redback 2.5" catsback with the additional rear resonator ($400 odd from ebay, delivered) does the job very well, and gives a nice note without being loud. If you want loud, then just order the system without the rear resonator. It bolts straight up to the factory position using the hangers on the stock system (you juts swap them over). To get this from an exhaust shop should be around the $400 to $600 mark as well, again, depending on city/town you live in.

Power increase anywhere from 3 to 15 rwkw (around 8 would be average)

If you get extractors, HF cat and 2.5" mandrel bent system all at the same time, expect to pay anywhere between $900 and $1200 for the lot. The $1200 is what I'd call an average cost, the $900 is the best quote you may get in the larger cities, due to increased competition between exhaust places. These prices are all for mild steel, BTW. No need to go stainless unless you have money by the truckload.

2. (a) Springs. King Springs, or Lovells, or even Pedders sports springs (XR equivalent for each is "Low") are around $150 a pair (or thereabouts). Whether they are Lows, SL or SSL doesn't affect the price either - they are all the same, but it sounds like Lows are what you should get for yours, and you will be happy with them, no doubt. So for a full set, you'd be looking at around $300 odd, plus fitting, which should be around 2 hours labour (around $200 max). I can do them in my garage in around that time, so a mechanic should be able to do them way quicker. So you are looking at say, max of $500 for springs all round (supply and fit).

2 (b) Shocks are around $100 per front corner for Monroe GT Gas/Reflex shocks - probably worth doing while you're there, as they need to disassemble the whole shock/spring assembly to fit the new springs, so doing shocks at the same time should be no extra labour charge - only the price of the parts. So you're looking at around $700 for front shocks, and springs all round.

2 (c) If you have a live axle (forte etc), then rear shocks should be around $100 a pair, so you might as well get them done at the same time, making the total bill around $800, but that gives you all new shocks and springs at a lower ride height than standard.

So, to summarise, for around the $2k mark (max), but for as cheap as perhaps $1500, you can get low springs, new (Monroe or equivalent) shocks all round, and a nice new exhaust system that should see some useful power gains.