FD with mods slower than stock?
 

My car is MEGA slow!

did 0-60 in 6.1

and 1/4 mile in 14.7

and that was the best run!

One of my runs was 16.3!

WTF?

Everywhere I checked the stats for this car is either 13.4 or 13.5 in the 1/4.
Whats wrong here?

Tell me what you think.

Your sig shows the exhaust and intake. Do you have an ECU or boost control?? A boost guage to check your boost/pattern? How many miles on the engine?

Need More Info!

Auto trans makes a difference too!

Its a mazda reman with 20k miles. No boost controller or boost gauge yet but will have in a few weeks.

Could the auto cause that much difference?
Ive never heard anything about that for RX7s where as the RX8s difference is clearly stated.

Exhaust and intake with no ECU or boost control?? Your damn lucky you haven't popped the motor yet!

Get that guage and some boost control before you go WOT again. Check to make sure your getting 10-8-10 without spikes at transition. If all is good, then the next suspect would be the tires and/or the driver.

No offense, but I think the problem might be the driver.

Auto's have a power decrease... I think.
I think its very notciable to.

i will say since it's an auto it's not the driver...

how are you launching? powerbraking? are you using the hold button on the shifter?

I've had times like those with my manual trans and the problem was turbo/boost related. you need to verify your boost pattern. If its not normal either you've got some bad plumbing and/or faulty solenoids in your turbo control system (which I had) or you need to play around with the boost control a bit (which I also had to do with a midpipe). midpipes change the backpressure alot and you will have to experiment with boost control and maybe backpressure restrictors in exhaust (depending on which catback/midpipe pipe diameter you have.)

of course if you've got old or "well worn" tires that could be the problem.

No boost gauge? You could be making only 7 PSI for all you know. Get a boost gauge then post again.

Brian

Hey lets all spread some false rumors!

Exhaust and intake are fine on a car without an ECU. 3-mods in the general rule, 2 is fine.

Autos have the same power as manuals.

Yeah but he has DP, MP, CB thats just asking for trouble, especially on the stock auto tranny, those trannys cant take much abuse anyways. Its not hard to race a slower automatic like that, I have no idea why your ETs are so far apart unless you were trying different launch methods. My guess is you are having boost problems or your dranny is slipping.

Re: FD with mods slower than stock?
 

Your 0-60 is about right for a near stock auto, but the 1/4 times are off. I suspect you probably have a problem with the secondary turbo. As posted above, you need a boost gauge.

Ok I got a boost gauge today but haven't hooked it up yet. I just put it on temporarily and held it while I had someone start up and rev the car. At idle the gauge showed and held a vac of 12. But when reved it never came out of vaccume, it went up closer to 0 but never went into boost.
Is this normal? Do you have to drive it to bring it into boost?
Thanks

Yould be making some boost even not driving it. The vaccum should be like 15-20psi at idle. You need to hook the boost gauge up so you can see it while driving though.

IIRC its should boost at idle, only under load

at any rate, get that guage on and tell us how it goes

Hey! Lets all review, before we jump in and flame!

As my post reads "no ECU or boost control". By this I was refering to the adjustible boost control capabilities of the aftermarket ECU's. With the completely open exhaust and intakes, comes an elevated boost level. Combine that with a spike at transition, and you could go "lean".


I wouldn't risk it IMO!

You probably have boost problems, and count yourself lucky that you do. With a dp, mp, cb, and intake, you will severely overboost with a properly operating turbo control system and hit fuel cut. The simplest way to get your speed and also keep your engine in one piece is to get a profec B, fix the boost problems, and then carefully adjust to the profec B to see if it can control boost to 10psi. Do not go even 1psi over that. Once you have verified you can control your boost on the street, I'd fill up with 100 octane and get the car dyno'd to verify your A/F ratios. The stock ecu runs pretty damn rich so you should probably be ok AS LONG AS YOU KEEP BOOST TO 10 PSI, but get it checked on a dyno. If you cannot control your boost with the profec, you need to either 1. Get the wastegate ported or 2. Put on a more restrictive exhaust (either get a HF cat or more restrictive catback). I suggest taking the car to a rotary mechanic and having all the vacuum lines redone, all the solenoids and check valves checked, and having the profec installed simultaneously. The vacuum job will cost ~$500 and the profec $200 or so, installation of the profec should be free or very cheap with a vacuum job. The dyno runs to verify A/F ratio should be ~$100. If everything works out right you should be running low 13s and I would just leave it there.

I was going to have the vaccume job done a few weeks back and I decided not to because someone recommended that I go non sequential since I have an open exhaust. Because of this I figured why spend the money to have the vaccume lines redone and then ripped out again in another month?
How much would it cost to have the turbos done non sequential?
I plan on getting a PFC, intercooler and radiator and then having the turbos done non seq all at the same time and then getting it dynoed and tuned.

I didn't think the PFC was compatible with an automatic tranny. Did you look into this?

ya, my auto was definetly slower in the quarter. The powerbraking is nice, but the stock tranny still sucks.

AND THIS OBVIOUS ANSWER IS A BOOST GAUGE. For all you know, you might have a vacuum leak

same bhp, yes. not like the rx8 which has a different engine configuration for the manual trannies.

but an automatic car will put less to the ground because of drivetrain loss.

victor

Chuckling@nonseq and stock stall on automatic.... no power till ~4000 wow no wonder the 0-60 times suck so bad.

The PFC works on the automatic. The problem is that it doesnt properly work the hold button (or whatever it is?) on the tranny.

OK I finally got my boost gauge in and...
my boost patteren is messed up.
its supposed to be 10-8-10 stock right?
well mine goes up to 6 then drops to 5 and then keeps dropping all the way to redline where its about 1.5.

What could be wrong?

Your car is sucking and the turbo not blowing. You have boost leaks somewhere, best bet would be to either do the vac hose job or take it to a nearby rotary mechanic.