I am in the middle of boosting at the moment. I have been gathering parts for about 2 months now, and i'm about 1 month away from the big day!
Here is my story.
What is needed: turbo, manifold, dump-pipe, piggyback computer, injectors, intercooler, Air Flow Meter from RX7, Recirculating BOV and gauges for boost and air/fuel ratio. Obviously all these things will require fitting and plumbing in, so piping, nuts and bolts, clamps and heat shields/material to go with them are included in the budget - AU$1500
1st purchase: the intercooler.
After scouring eBay for the cheapest option, I decided to go for a new intercooler (second hand are not much cheaper) in a 550x140x65 size, with 2.25” inlet and outlet. After realising I was bidding against a fellow forumite, I decided to let this particular intercooler go. However, 1 day before the end, he was outbid, and it was still in my price range, so I decided to go for it. Success! $51 + postage for brand spanking new. As the seller was in Brisbane, I asked if I could pick it up to keep cost down.
Total so far = $51
2nd purchase: the turbo.
I was told that the SR20det turbo was a better package, although a little more expensive than others, such as the RB20 turbo. I managed to find one in my price range, and put in the bid. As it was also in Brisbane, pick-up is the way to go, and cost was $260. The turbo has no shaft play and doesn't blow smoke, so i'm happy. It also has the stock dump-pipe on it, so i may be able to use this to keep costs down.
Total so far = $311
3rd purchase: Jaycar air/fuel mixture display.
After looking on eBay and in different stores around the place, I decided I wasn't really happy with the bar graph displays or the gauges with just "rich," "stoich" and "lean," so I started looking for a digital display. Wow, these are expensive. Jaycar has a build it yourself kit for $63, so I bought one and tried to have a crack at it... I soldered everything, but testing and installing takes more knowledge and skill than I have in this area, so it's going to cost me a 6 pack of beer to get a mate - who is studying electronics - to do it for me!
Total so far = $374 + 1 6pack of beer
4th purchase: the manifold.
I went ahead and contacted a seller about postage for one of these eBay manifolds from the US to Brisbane. He replied promptly and told me a price, but said he was willing to give a massive discount if I ordered multiple manifolds, namely 4. Hmmm, I contacted a friend from the forum, the same guy who was bidding on my intercooler, and asked him if he was interested in helping me fund this venture. After explaining that I intended to sell the other 2 on eBay to get some money back for them, he agreed, and I ordered them. They were shipped by FEDEX and arrived within a week! Straight to my mates workshop to begin fabricating a spacer for the T2 flange. We put our heads together and designed what we need, and began work. Another 6 pack, excellent. Assorted bolts and the T2 flange gasket cost came to $23
Total so far = $397 + manifold + 2 6packs of beer
5th purchase: the GReddy eManage Blue.
I was going to leave the piggyback for as long as possible, and just wait for the right thing to come along... It wasn't long before a deal came along that I couldn't resist. The eManage Blue is a fuel computer which can also adjust timing, which is a massive bonus, and this particular one is second hand, and comes with the support tool and cable, injector harness, which allows you to run larger injectors than the stock ECU can handle by itself, and timing control harness. All up I bargained the price to $500 delivered. It is 1 year old and has been used to run this guy's GReddy kit at 130rwkW.
Total so far = $897 + manifold + 2 6packs of beer
6th purchase: Toyota Supra 305cc injectors.
While reading some information on www.miataturbo.net
I found the DIY FAQ. Information in this thread lead me to start searching for different types of injectors, and finally, I found a set of Supra injectors for $72 posted. These are a direct fit and will supply the required fuel for the purpose.
Total so far = $969 + manifold + 2 6packs of beer
7th purchase: Rx7 AFM.
There was never any doubt where I was going to buy this. A mate of mine and his little brother swear by Rotary Motorsports in Brendale, and they get everything there, including tuning their piston cars! I asked my mate to get me a price on the AFM and he said $30. I couldn't find one anywhere for $100, so I agreed without hesitation. When we got to the shop, it turns out that the particular model AFM I wanted wasn't $30, damn, it was $25... SOLD!
Total so far = $994 + manifold + 2 6packs of beer
8th purchase: Rx7 recirculating blow off valve.
This one was simple too, I was driving past Phil's Rotaries and decided to pop in and have a look. I remembered that I had forgotten to get a BOV and asked if he had one lying around. He sure did. Factory recirculating BOV from an RX7 was $20. I'll need hoses to plum it in, but that is expected.
Total so far = $1014 + manifold + 2 6packs of beer
This info is on my website, which is why some of it is explained in baby terms... Please free to add any comments, but anything I have written there is based on information from either here, or some vrey experienced turbo guys in Australia, so changing my mind will be difficult!
EDIT: Boost Gauge $20 on eBay
Total so far = $1034 + manifold + 2 6packs of beer