Was just wondering if any of you normally aspirated guys out there can help me crack the 200 horsepower barrier.

To start off with this is the car in question, these are photos taken from before I bought it but nothing has changed.





Mods at the moment include:

-RX4 13B bridgeport
-50mm injection perfection with 650 siemens injectors on a manifold which has been match ported to the motor.
-Series 5 turbo gearbox with brass button clutch and light weight flywheel (extremely fun to drive in start/stop traffic)
-17" Simmons (Has to add at least 10hp right?)
-series 2 diff with 4.1 ratio
-Exhaust is 2 x 2inch pipes running from the engine straight to the back into a 2.5" Racing Beat muffler.
-Koni shocks and king springs, cusco front strut brace and adjustable camber tops.

Anyway, I recently got it dyno tuned and it made 194hp at about 8500 rpm.



So the question came up, what can I do to make over 200hp?

 

Holy **** *****! Your 1st gen is BEAUTIFUL!!!!

 

lighter weight oil? either way, its impressive man, congrats

higher flowing muffler?

 

Are those LS1 coils? Very nice setup, I want mine to be like that!

 

lighter flywheel, better header maybe (SDJ if you can find one), Even though NA, maybe try a higher octane fuel if not running that already, racing fuel ... is all the above don't work time to boost or make the porting just a tad bigger


Very nice clean engine bay .. I plan on going with those style IDA injection system myself... are all four of your injectors 550cc? Are you running a haltech? Also what kind of ignition mod is that ?

 

I'd say the Racing Beat muffler is holding you back a lot. Bridge-ports need a very free flowing exhaust to make full power.

 

nos setup could gain u the extra hp
or could u get bigger injectors and change the timming a bit?

looks like u have a very well thought out setup what kind of igniton coils are those

 

That's a hawt spoiler.

 

royal purple oil, free up the exhaust, and you can add a lil Nitrous for a kick in the butt also what ecu are you running? who did the map for it?

you can also try grounding the motor better... i know it sounds lame and like some ricer crap but it helps.. do 8 ta 10 even grounds around the motor with some 4g wire it "CAN" help not sayin it will help but good grounds dont hurt anything...and it looks like you motor is tied down like its going ot jump out of the car... kinda like a crazy dog woot... for the 20 bucks it cost to make it wont hurt


edit: your car is goddamn BEAUUUUUTTTTTIFULLLLLLLLLLLLLLLLLL

 

Holy ****, and I thought this was going to be another 15 year old asking a bunch of wacky questions. Very nice car, man.

Would the muffler be holding back six horses worth of power?

I understand it's more restrictive than the rest of the exhaust system (if I read his post correctly) but do you think it's choking the power output off a lot or just a wee bit?

 

RB mufflers are not free-flowing at all. Any reverse flow muffler is gonna kill power, especially up top.

 

OPEN EXHAUST!!!!! let the dragon breath

 

first off beutiful car,that said a large streetport will make 230 hp,a bridge will make up to 300,i would say your tuneup is way off,how much timing etc.

 

Yeah, I can understand that.

I don't know if the noise level that you'd get from running two inch straight pipes off a bridged engine back to a "straight through" type of muffler would be worth the extra seven horsepower needed to break two hundred (for me, anyways, I'm sure other people wouldn't mind at all) but I can definitely see how it would help with the power output levels.

 

Pportnosgsl where do you get those figures from? I was under the impression that 194 from a bridgeport was fairly decent. Have you got any idea how they make that much power without boost?

The car has been professionally tuned by a rotary workshop and it's running a Microtech LT10s computer.

I understand that the muffler may be holding it back a bit but it's already loud enough to attract unwanted attention and I live in a decent apartment block where I don't really want to **** anyone off.

NOS would be an option if I was going to race it but I daily drive this car and trying to keep it as street legal as possible.

It's already got a swiss cheese flywheel so it's not going to get much lighter than that and I run 98RON fuel in it (highest octane you can buy from a gas station here).

 

as i reread your post,a couple of things came to mind.1,a 50 mm throttle body should be on a peripheral port,or a monster bridge,since i don't know what size the bridge ports are,i'm gonna say they aren't real big,i'm thinking the engine falls off before the induction hits it's sweetspot,the bigger throttle body make the motor make the power at higher rpms,your exhaust isn't bad,i run 2 2inch allthe way through,i use 2 powerpulse presilencers,and 2 walker superturbo mufflers,13b pport 51 ida,my engine makes 315@9800 no bottle.

 

Very nice, what car/truck is this engine in?

 

RX7,here on the west coast i have put a weber carb and some good exhaust and made 200 hp on a stock 6port 13b, my second motor i ever did was a 13b bridgeport not into the water seal area,it made 240 hp,it all depends on port timing.fuel system,we have had trouble with 2 of the microtech systems here,they have a rich spot at around 3500 rpm that we can't fix,microtech tech support won't help figure out the problem,one of the cars is 3 rotor 10th an RX,med streetport,single GT42r.

 

my first gen RX-7,it will be out and about this summer,ilove to drive it around,people stare.

 

So I should be running a smaller throttle body?

 

i have read that the NA rotarys make more power on a lower octane... that mazda used low 80's in there race car NA only caz you dont have to worry about detanaton as much

 

yes,i would say a 48 mm,i know its not a big jump,but you can also take some fuel out,that brings me to another question,what is the afr reading.

 

true,my peripheral port makes 315 on reg 87 octane,i love it.

 

Lower the octane! Try 89 octane, you should pick a good amount of power. And like everyone else said, ditch the racing beat rear muffler, and get a straight through design. Then add two more pre-silencers in the mid section.

 

Is that rwhp, or flywheel? I want to see that dyno!