So heres the plan....... NOT BLOWING THE 13B UP! Haha. Basicaly for now i want to run 3'' turbo back single tip, delete the airpump/AC/all other useless crap that can break, also i want to run a good intake (not sure what to buy yet). I only want to run close to stock boost level (6psi i think), I know porting the wastegate on a stock S5 turbo wont bleed enough exhaust gas. So what are my options... turbo upgrade with an external wastegate? Im not looking for too much power (250hp... 200whp).. just drivability and gas milage better than 10mpg..

 

for only 6 psi and an upgraded exhaust and intake you wont need and external wastegate

 

Sweet. I cant wait to get this project rolling. Thanks

 

You only need a external WG if you get boost creep becuase your hotside is too small for the hp/boost level you want to run.

I suggest you first mod the driver, of course and just make sure you have good tires, the brakes are bled and have good pads on them, bushings, no worn out shocks/springs and the bearings are all in order, and then learn about turbos before doing anything signifigant.

Its not hard to learn and teach yourself about them via the internet, but it will take time and actual comprehension. There are also several books out there that can help (some are a bit dated, but still useful) but you really should at least understand what a compressor map is, how to read it, and why saying a turbo makes boost is like saying a dairy farm makes manure.

Also, get some good tires.

And now that I've ranted, the stock turbo when maxed out will spool early and start to taper off as rpms go up (remember, turbos dont make boost, they pump air...) because the engine will actually suck in air too fast for the turbo to huff it out in time to build up a high pressure ratio (aka boost).

Basically, if you max out the boost of it as far as it will go, It'll give a powerband not unlike a v8 or a wrx... might be your thing, its definitely not what most rotaries are, good for a newbie and on an autocross expecially, but your stock turbo can only go so far. If you run lower boost (such as what it will taper down to at redline) the whole time, it'll be more linear but not have the midrange.

Also, just the way I think about things, a standalone or piggyback of some sort to be able to have control over the tune is a very GOOD THING with any car... especially a RX-7. You may not need it as mazda likes to be rich to be safe stock, but... well, it cant hurt to get a good tune, and it can hurt to run too lean!

 

Roger that. I know how the entire system works, what everythign does.. were they go etc. I just need to get my hands dirty with a project and see all of my knowledge being put into practice. I just want to do it right the first time.. lucky for me i have a good buddy what built up his FC and did it right.. so hes pretty knowledgeable.

Another noob question.... What have you found is the best turbos for low boost applications, that is 10psi and lower? I mostly want fast spooling and small turbo lag. Thanks

Oh and FTW power upgrades are last on my list of mods. I was going to take care of everythign else first... Suspension/brakes/tires/filters and fluids/ hoses/cooling etc etc.

 

i would get a FCD and boost 10psi daily.. thats how my old S5 was. i never got boost creep or anything. ran 13.9 with the mods you just named

 

FCD? So basicaly as long as your running enough fuel.. and under 300hp.. your engine wont blow up from boosting?

 

just to be on the safe side from running lean, you should up grade your fuel system and get a Rtek.

 

Ya I definatly want to do something about the fuel.. make sure im a little bit rich to be on the safe side. I really dont want a gas guzzler though, what kind of gas milage are you guys getting with the mods i have listed?