m477

I'm buying a Black 94 R2, and it's getting a new engine done at Rotary Performance, so I thought that I might have a few goodies installed while it's there (essentially I won't have to pay labor for most things, since they're gonna have the engine out anyway). I'm not looking to have a heavily modify the car, I want something that's balanced and reliable. So here is the list of stuff that I'm thinking about, please share your comments!

Stuff I've Decided to Do
Engine: Mild street port, OEM 2mm 3-piece apex seals
Silicone Vacuum Hoses
Downpipe
Aluminum AST
GReddy radiator cap

Stuff I Might Do
GReddy blow-off valve (standard spring)
Bonez Street-Comp Clutch
Aluminum Flywheel
RB Dual Tip exaust
Mazdaspeed short shift kit

Stuff I'm really not sure about
ECU
Fuel System
Gagues

Mahjik

iTrader: (1)

Looks good. However, I would skip:

GReddy radiator cap
GReddy blow-off valve (standard spring)
Fuel System

Unless you do some more heavy modifying, you don't really need to mess with upgrading the fuel system.

You should also move the "Gauges" up to the "Stuff I've Decided to Do" area. A boost gauge is almost a must and will be invaluable should you have problems down the road.

Good luck.

GsrSol

I would go ahead and do a clutch for sure.

You can also do Efini Ypipe or pulleys. I wouldn't do the short shift kit.

ttpowerd

Yea, go ahead and get them to install the clutch and flywheel while it is out otherwise it just racks up the labor costs later down the line. Plus you can break in your clutch at the same time you are breaking in the engine.

turbojeff

iTrader: (30)

Don't bother with the BOV, stock are plenty good. Greddy rad cap is a waste of $$.

I'd do the clutch for sure.
Cat-back exhaust is nice too.

Don't do the ECU unless you do more mods.
Get a boost and temp gauge.
Fuel system mods don't need to be done until your pumping some serious HP.
The short shifter is a preference thing, I think the stock shifter has pretty short throws. Short shifters tend to be a little more notchy and require more effort to shift.

Jeff

m477

So with streetport + DP + catback I won't need a new ECU?

But if I upgrade the intake, I will definitely need to upgrade the ECU, correct?

rynberg

I agree with others, your list should be:

DO
streetport
downpipe
gauges
silicon hose upgrade (actually, I'd use Viton)
aluminum AST

MIGHT DO
clutch and flywheel - depending on current condition of these parts
ECU - talk to RP about this, depending on how large a streetport you are getting, may be desirable, but only if you also get the cat-back.

Any of the other things will not be cheaper with the engine pulled. I would also skip the Rad cap, BOV, and fuel upgrades. You can install the short-shifter anytime.

93TTRX7

I'd go with a fludyne radiator and a stock mount intercooler instead of the catback exhaust...i wish I did that with mine.

turbojeff

iTrader: (30)

Make sure your fuel system is up to par. Clean injectors and change the fuel filter. If your running stock boost levels then you won't need an upgraded ECU. Even if you add an intake you won't need an upgraded ECU but you'll have to make sure the boost is at stock levels.

I've tested my car with a wideband O2 sensor, stock ECU, DP, CB and Efini y-pipe. A/F ratio pegged the meter at 10:1 ~2500 rpm to redline in 4 gears. Added an M2 CF intake to the same car and got the same results.

Check out Wade Lanham's website he's done some pretty extensive testing of modded cars running stock ECUs at stock boost levels. IIRC all of them still ran rich.

Wade speak up...

Jeff

Wade

iTrader: (1)

I'm speaking...

Jeff is right. See the info at www.wvinter.net/~flanham/wlanham .

On a related note, many people include an ECU (often Power FC) in their list of suggested mods for reliability. I wouldn't consider a PFC a reliability upgrade at all for a lightly modified car, given that it loses the knock control of the stock computer, and it appears the base maps are actually leaner than a stock ECU.

Not to suggest that no one needs a programmable computer, I'm just suggesting that people who don't need an ECU probably shouldn't buy one, and an ECU upgrade doesn't automatically mean richer, safer, or more reliable.

Wade

m477

Thanks, Wade.

I guess the main thing that I don't really understand now is the relationship between A/F ratio and boost PSI.

So is there a point to doing mods like intake + catback while running stock boost levels? Why or why not? If you're running stock boost, and the A/F ratio hasn't changed, I don't see how there could be any benefit (or any reason to spend an extra $700 or so) in that case. I've been searching for an answer to this, but I haven't been able to find anything conclusive or any good explainations.

95R2-89TII Ground Zero

Yeah you have to have a boost gauge. As for the rest of the of stuff, I would get everything except the radiator cap, BOV, and Fuel system

Wade

iTrader: (1)

Yes, even if you keep the boost at 10psi you will still gain some power from mods. There will be less work for the engine, and also the a:f will get slightly leaner. Both of these result in more power. However the greatest power gains come from raising the boost level. I think with normal mods an FD should be able to get close to 300 rwhp at stock boost levels.

There is a point when modifying a car will result in the a:f being leaner than you want. Stock cars run about 10:1 or richer at 10psi. My car with all the normal bolt on mods and no cats, runs in the 11:1 range at 10psi of boost. This is an acceptable a:f ratio for my mods, but I wouldn't recommend running that a:f on an otherwise stock car.

If your car runs correctly and you have some mods (but less than I have), your a:f should be somewhere in the middle, likely still in the 10.X range.

What's your question about the relationship between boost and a:f?

Wade

djantlive

http://www.rx7turboturbo.com/robrobinette/

http://www.scuderiaciriani.com/rx7/

http://www.rotarypowered.com/suspension.html

Some good sites to read up on.

I would start with fixing anything wrong with the car (idle, smoke, vac or oil leak, worn suspension, clutch, leaky fuel injectors, faulty fuel pulsation damper, leaking LIM gasket), change all fluids if due, and then the following basic mods to start:

DP, Intake (Apexi or Rx7fashion or M2), CB, ECU.

Street port is big bucks so do it when your engine blows.

m477

Basically you just answered it. I wanted to know if a:f could change independent of boost psi.

RZFD

Aren't we ever the optomist.