Hey guys, I recently bought an FD with mods listed below, also it was a claimed 410rwhp car. Car runs great etc but I had a few questions. I am new to rotaries and reading up constantly and wanted some more opinions on what could be the problem..

the car put down 257rwhp sae on 93 octane running 15psi... the power curve was pretty consistant and the a/f readings were in the 10's... maybe I just need a tune? I really dont know but realistically I would like to get that power out of the motor. I'm not even sure if the motor is ported, which could be holding me back from making the power that was told to me by the last owner.. I dont know, I'm just looking for some ideas... I've talked to a few other FD owners and they were stumped as to what was wrong, I thought maybe the owner did a "glory" run and pushed the boost up and ran the 410 but then lowered it to sell it...

shrug, never hurts to ask...
anyway
here are the mods

ENGINE MODIFICATIONS:
REBUILT MOTOR
GREDDY T78 SINGLE TURBO KIT-- INCLUDES T78 TURBO, DOWN PIPE, STAINLESS
STEEL MANIFOLD WITH EXTERNAL WASTEGATE + DUMP TUBE AND MISC.
HKS EXHAUST
KOYO RADIATOR
GREDDY FRONT MOUNT INTERCOOLER
BOSCH 1600 INJECTORS
CUSTOM FUEL RAIL
B2 FUEL PUMP
ALL BRAIDED STAINLESS STEEL FUEL LINES WITH CURVED ELBOWS
SX FUEL PRESSURE REGULATOR WITH GAUGE
GREDDY POWER PULLEYS
RADIATOR CATCH TANK
GREDDY TRUST TURBO ELBOW
GREDDY RS BLOW OFF VALVE
BATTERY RELOCATION TO TRUNK

ELECTRONICS:
APEXI POWER FC STAND ALONE ECU
GREDDY PROFEC B SPEC 2 BOOST CONTROLLER
GREDDY TURBO TIMER
AUTO METER BOOST AND EGT GAUGES IN CARBON FIBER ON DUAL A PILLAR GAUGE
POD

 

Dyno might be reading low, REAL low.

How did it sound on the dyno? Clean? No breakup?

How did it boost?

 

sounds good, smelled a little rich but no break up's...

except one run the car completely shut off under boost, which scared the crap out of me. but started right back up again and ran fine...

boost is good and smooth, i can post up the dyno sheet later today and show the power curve.

edit: the motor only has about 6k miles on it right now too, didnt know if that made a diff

 

yeah, post up a sheet.....

do you know anyone else who's used that dyno. What brand dyno was it?

whatever you do, don't try and adjust anything....... save that for a tuner

 

Oh believe me, im not touching the tune or boost.

 

How long ago did you buy it? Did you change anything since you bought it? I had a low rwhp run once when I switched to a different sparkplug (B10EGV)...switched back to stock 9's and hit over 400rwhp... Who knows?

I would call the previous owner up and see what he says...that doesn't sound right for 15psi.

And do post up the dyno sheet...we might be able to see something odd.

 

Looks like he just bought it, Aug 17th.

 

Another thing I just thought of is i didnt really spin the motor that high for fear of blowing something since the internals of the motor are somewhat unknown to me..
What is a safe rpm to run the car up to?

and no i didnt mess with anything on the car, there was a previous owner who had the car for a little less than a year but I dont know if he did anything to it while owning it... i will ask him though.

 

compression check? I would do one of those first. A few other things can change dyno numbers is if they didnt input the dyno perameters in correctly. Is this a shop that has dynoed a rotary before? Good luck on your new purchase.

 

as far as the dyno is concerned, its more a subaru shop with an AWD dynojet (which was set up for 2wd on my run) which might make the numbers seem low... yet some (what should be) slower cars dyno'd higher than my car did.. I will check compression even though with how well the motor runs I doubt that is an issue but i will still do it anyway.

the motor on the car is solid, i drove it 6 hours straight from NYC to VA and it did great the whole way.

 

I let a guy that was strictly muscle cars drive my old FD. He kept shifting at 5500 rpms and smoking my clutch...

Did you take it to ~8500rpms?

Where is the boost guage hooked up to?

Ignition problems?

 

www.boostpro.net/prodtester.html or just rig up some home depot stuff

pressure test for boost leaks before anything else.

 

how far did you take it?

 

Why was the engine rebuilt? Did it blow apex seals? If it did, then they shredded the turbine blades, which would cause the low HP numbers if the turbo wasn't rebuilt also..

 

Since you are not too far from one of the best shops for an RX-7 I strongly recommend taking it to http://www.pfsupercars.com It can take a long time to get your FD in there, since they are extremely busy. Also, who did all the work on your FD? There are a few shops in NY that I would personally never go to, since they purposely damage the cars.

 

Something is way off on your car or the dyno. Even with a very rich tune it should still make more than 257HP with a T-78 at 15psi.

 

Yeah, say you even had a boost leak and you're overboosting the turbo and seeing 15psi at the manifold, it's still low. I don't know, I would still check the basics like ignition.

 

right now im trying to get in contact with what i think is the original builder, he's on the forum.. username is Rotor3

 

You said you didnt rev it that high. How high did you take it?

 

stock gauged redline, i know it can do more but i didnt want to risk it since i dont know what all is done internally

 

It's one of two things. One is low compression and the other is the dyno reading out low. How does the car boost? Does it come steady on? Does it just seem to overall lack power? I'm betting it's lacking power and that will a sign that the motors low on compression. A T78 should be 400whp at 15 psi. I don't think the turbo is the culprit as if the wheels in the turbo were severely damaged they wouldn't be able to make the 15psi. Time to pull the plugs and get dirty...

 

I would verify that the leading ignition system is working. Running on just the trailing ignition will produce the same results you are seeing.

 

Get a decent tune on it first.

no reason to be running 10's.

 

The tune alone isnt going to lead to that kind of power production, assuming that you're revving to 8k rpms (wouldnt recommend 8500 unless the motor is built/ported for it). You have some other problem.....

 

Didn't say he's not making alot of power b/c tune alone.

I think he has multiple problems with his car but he needs to fix one thing at a time.

That's why i said fix the tune first.

If he can't fix the tune you can narrow it down to fuel and so forth.

Start with what you know is wrong and keep trouble shooting until you get something reasonable.

Reason you have to take it one problem at a time is b/c alot of times faults will hide other faults.