I don't see a 350hp rx7 keeping up with a C6 ZO6. I sell them. I've driven them. Not very likely. And if it did happen, it wasn't for long.

 

That's what I was thinking. I remember a few years ago when 360whp was the magic number for the 7 to out run most production cars on the street. Namely the C5 Z06, 911 Turbo/GT2, Viper, etc. But I thought the 7 would need somewhere around 415-430whp or so to run with the C6 Z06?

 

maybe you cracked an apex seal trying to race a Z06 while on a tune not meant to handle a midpipe. .... Oo

 

some people have really cool wives

 

your not properly tuned.. ive put down 275rwhp with less mods than that..

 

Well I wish I could say I knew the right answer but the previous owner has lied to me about a LOT of things on the car. The hiflow exhaust was a random tech not a bonez, the wastegate actuator wasnt even hooked up when i bought it - he said it was jsut running low boost...

However I do have the receipts of the injectors from RC engineering and as far as I can tell they have only as many miles as the rebuild. My biggest concern is that the stuttering of the car under WOT became evident sometime last summer, thats why I took it to get tuned. However even after the tune the car is undrivable under WOT conditions. The midpipe and tune helped a little but not much - flooring the car is just embarassing the way it shakes and stutters.

At this point I'm ready to throw in the towel - it's way beyond my feeble understanding. The problem is that there are no good rotary tuners in my area since sevenspeed closed down and rx7store is moving. When the car started doing this rediculous stuttering under WOT I got it tuned - it kept doing it after I got it tuned so I jsut assumed this is the way it was supposed to be but after nearly losing to a stock srt-4 theres no way it can be right.

Also plugs, oil, and oil filter all have > 1500 miles on them - I replaced them last summer when I noticed the problem.

I have not replaced the fuel filter since I bought the car, so I will try doing that.

 

To echo everyone else, yeah, get a good tune. Especially since you now have a midpipe.
FWIW, my stock FD walked two different stock SRT-4s quite badly from a ~45-ish mph roll. One stock SRT-4 was making 14lbs, another was making 16-17lbs stock(excellent QA by Mopar ) Brake boosting from a 45 roll made it even worse on the SRT-4. A properly running stock FD should walk the dog on a stock SRT-4 from just about any roll.
Hell, even my stock BMW 540I barely walked on a stock SRT-4.

 

Not really. It has turned into a "trouble shoot my problem" thread.

 

The age old answer.. Its as only as good as its tune. I would be afraid to blow the motor if I did not know exactly what was going on and jamming the pedal through the floorboard.

 

Thank You!

 

find out and make sure he is not staged. i have an srt-4 and with stage 1, map clamp, and wastegate, that puts my car right around 265-270 to the wheels...granted it's going front instead of rear or all..damnit

 

when is this? I need a slight retune.

 

Yeah, you should destroy that car if your fd was running correctly. I have similar mods as you and on 10psi 3 days ago i ran all over a stage 2 mopar SRT4. 40mph roll to well over 120... wasnt even close.

 

How old are your plugs/wires? Im not sure what the stuttering is you are feeling at WOT, but Id bet its ignition related. Possible its running so rich that the plugs cant fire the mixture correctly? Maybe its time for an ign amp, and a RETUNE.

EDIT: Just noticed you said the plugs/wires were 1500 miles old.

 

Describe your stuttering..

Does it fall on its face, then back on, then falls again??
You could be over boosting and hitting fuel cut.

or

you might need an ignition amp, like HKS or MSD

 

okay, if he got tuned already, and its suttering under WOT, that leads me to think that there is a problem that needs addressed. First off, i could take the car to a mazda dealer or someone else with an actaul rotary compression checker, and get some solid numbers on the condition of the motor.

Then if the compression is keen, look at your fuel system and your ingition system, the first being fuel. Shutter sounds like a lack of fuel. Its possible your fuel pump is crapping out. What you should do it connect a fuel pressure gauge and try to mimic the shutter, which should be hard, and see what the fuel pressure does. When my FD pump died in my TII under wot, it shutter VERY bad and got worse to the point i couldnt drive the car.

If the fuel pressure is working fine, the injectors could still be in question.

If the fuel system checks out, look at your igintion. Wires, Plugs? Take the leading plugs out and see what condition they are in, or better yet take them out then immedaite take good close up pics and post them up for us to see.

Doesnt sound like a timing issue. And there is no MAF sensor to have a vac leak unless a charge pipe is opening up a bit under boost.

 

If you have been running the same fuel filter for awhile it would not cause you to run rich it would make you run lean.

For oil and plugs, if you drive your car very little it should be at the opening of every summer no matter what mileage you have done.

Lastly, from experience, when I was juste midpipe and catback I was dead even with an SRT-4.

Now with a intakes, intercooler, downpipe, high flow cat, catback, and pfc tuned by Steve I demolish bolt on SRT-4's especially after 5,000 rpm. So get that car up to date in the maintenance schedule and get it tuned right so you will be killing them too

Good luck,

Alex

 

You ought to find someone with a datalogit and wideband and go out and log some data under WOT. It freaks me out to hear you get a stuttering @ WOT Post up in the PFC forum and the guys there can most likely help you out. Good luck.

 

Do you have a graph of the dyno sheet from the tuning session? If so, does it have the A/F plotted as well?

What's the car's idle rpm and also what vacuum is it pulling at the rpm?

Tim

 

It was the coils, swapped em out and it runs fine under wot now

 

Then the obvious statement would be ....race him again. Although you need to retune the ecu, more than likely he took fuel out since he thought it was running rich...it was since it wasn't giving full spark so it might be dangerous lean now that you are.

Tim

 

I am in need of a tune, yes I know this much. I dont think it is dangerously lean, Im not getting any knock readings from the pfc and my a/f gauge isnt acting strange. In all honesty I still think it is running rich - my mpg and tailpipe still indicate it. I know it it needs a tune one way or another since I put a midpipe on it, but Im having trouble finding someone in my area with a wideband and experience.

 

BUY A WIDE BAND. AEMEUGO =$200.

 

I have almoust the same config that your carsnd I'm running at 10psi , I have never race with that truck but I think that the Rx-7 should be faster , I have race with the Porsche 996 gt3 in a track , mines was faster in the strait line , but in curves the GT3 just kill me.

Check out you A/F there is a lot of diference if you R running too rich , and try to buy a Aphexi AVC-R it works perfect.

Now I'm going to single turbo , cause I have another how was single converted and it runs much much faster at the same 10psi, it get to the 170mph so fast, it was so fast that my bro crush it and leave it total lost.

 

that's horse **** with your mods