FreedS4

I'm new to the RX-7, but i am in love with them. I just got an 87 Turbo II. I haven't done anything to it yet and don't know where to began. I don't want to go too outrageous with this car, i kinda just wanna get to know the rotary. I have plans to remove the A/C and Air Pump. I also plans for a Bonez intake and some kind of exhaust. I have a few questions though. Is it worth my time to remove the A/C unit and the air pump? What gains will i get from removing these? And is the Bonez intake good? What is a good inexpensive complete exhaust system? What else can i do inexpensively to gain a little more power without losing a lot of reliablity?

Thanx, any help is appreciated, chris

vaughnc

FreedS4,

Hey welcome to the forum.

Which direction are you thinking about or are you just considering options?

Good news - your drivetrain can handle 450+HP very well, but you need to upgrade carefully to prevent engine damage.

If your thinking of removing things to recover used HP & lighten the car that is one way to improve your 0-60 and 1/4 mile times. Personally I'd avoid removing anything unless your are committing this car for racing.

Most people divide modifications into stages. There are definilty quick mods to increase boost and increase flow to make more HP, but I'd be cautious of any mods you make. You should install gagues to monitor your air/fuel mixtures, boost (in PSI), exhaust temp, and coolant temp. After this then you can work on stage I mods:

Note many recommend saving your $$$ and just buying the Haltech or similar ECU upfront as it's cheaper in the long run. From this you can tweek your car much more (boost, fuel/air maps, etc..) Your other options are to buy devices to fool your OEM ECU into allowing more boost, fuel delivery, etc.. You can also move away from fuel injection and go carbed.

Stage I: (good for 240rwhp)
Performance cat, down pipe, performance exahust, performance intake, cold air box & cold air headlight intake (check mariahmotorsports.com for those), gagues, igintion, etc..

Note intake & exhaust mods on a turbocharged car will increase boost from 1-3 PSI above stock. You'll need to monitor the gague to make sure your not running to lean (which will pop the engine).

Stage II: (good for ~280rwhp)
Front Mount Intercooler, fuel pump, drivetrain mods (lightend flywheel, stronger clutch)etc..

Stage III: (good for 450+rwhp)
larger fuel injectors, fuel rails, Haltech ECU, larger turbo, etc..

Stage IV: (unlimited rwhp)
adding a 3rd, 4th, or 5th set of injectors, 3 rotor engine upgrade, etc..

There are a BUNCH of websites with rx7specific upgrades. As a start you should check the links section on this forum for a good list. Off the top of my head - teamfc3s.org, racingbeat.com, fc3s.org, mariahmotorsports.com, corkspot.com, victoriabritish.com, etc..

Besides peformance upgrades, you also have a wide variety of bodykits, general accessories, and mazda upgrades.

You might also check other's mods list for other ideas.

-- vaughnc

BogusFile

Um, the stock turbo can only support about 260hp before it starts spilling its guts. I think the HP levels are inaccurate acording to your stages. 240 RWHP with exhaust and intake? Even with the cold air induction, it just doesnt sound right. A stock 87 TII puts down about 150-160 RWHP. Are you saying stage 1 adds 80HP?

Felix Wankel

You're better off not buying a Bonez intake, they are horribly overpriced. Go to www.k2rd.com and get the HKS air flow meter adapter, then buy a K&N cone filter. Same results, much cheaper.

FreedS4

Thanx to all of you. Felix, whats a good inexpensive exhaust? And should i remove the A/C and air pump or no?

Felix Wankel

Bonez and Racing Beat I think both make 2.5'' downpipes. That would be the best place to start. I have a Racing Beat 3'' downpipe on my car, but it requires some welding to make work, since its not a stock replacement.

vaughnc

Yeah I was going by what I've read in the past for 89+ Take 15% off the top

Side note - previous notes mentioned stock fuel system is only good for 240rwhp while the oem turbo (with fuel deilvery upgrades) is good for 12PSI / 300fwhp. Are those #s about right?

FreedS4,

Your call on removing but I've heard ~15HP is about all you'll get back. Felix (I'll have a rx7 BB too) Wankle might know more about specifics.

Which direction are you thinking about??

-- vaughnc

FreedS4

At this point i'm just kind of experimenting. I don't use the a/c anyways so i was gonna get rid of it. And the air pump, i dont know what it does and dont know why i need it or don't for that matter.

vaughnc

Yeah AC's a must in Atlanta, so I kinda feel "severing your leg" is about like removing it (although having the windows down at highway speeds feels great).

Air pump I believe is for emissions & decelleration - it shoves more air in the cats I believe (correct me if I'm wrong people).