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-   -   230 hp, i want to be at 270-280 (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/230-hp-i-want-270-280-a-424620/)

Meiogirl 05-10-05 03:51 PM

230 hp, i want to be at 270-280
 
i got my car dynoed this last weekend at mazdafest. i was dissapointed at my results; only a 10 hp increase over my last dyno before my mods, new reman, and hose job.
there were some factors: i had just run the car on the track so she was hot, and when i got home i had some belt noise and i noticed the AC bolt you loosen to adjust that belt was loose enough for me to turn by hand.

so could those factors affect my HP?

what other things can i do to get 40 more hp without 'openning a new can of worms' persay? i figure 40 more HP will still keep in a safe range but give me a reason to have done the mods in the first place.

Saner 05-10-05 04:05 PM

Aftermarket ECU

vchacon 05-10-05 04:17 PM

+ catback + downpipe + intake + manual boost controller to keep your boost at a safe level.

Maybe a hi-flow cat.

Edit: just saw you sig... nevermind... I use similar but with a Pettit ECU and boost at either 10 or 12 PSI. I don't know why you got such low numbers, though. I would have guessed at or above 275 hp with your mods.

John Magnuson 05-10-05 04:25 PM

She has the Knightsports ECU.

I would say that the main thing restricting your output right now is your stock intercooler. At the 10psi boost your running I don't know of anyone who gets 270-280 RWHP with the stock twins and stock motor unless they have an upgraded intercooler. Since you already have the M2 intake a nice M2 style stock mount intercooler would fit well. It shouldn't cause any reliability issues either.

I'm not very familiar with the Knightsports ECU. Does it come pretuned or did you have someone tune it for you?

-John

PS Are you going to be at the SD meet tonight? If so what time?

rynberg 05-10-05 04:29 PM

Were the results on a Dynojet, SAE Corrected? What boost level are you running?

Your numbers are extremely low, even for 10 psi. With those mods you should already be in the 270-280 rwhp range at 10 psi. Either something was wonky with the dyno results or it's troubleshooting time.

DaleClark 05-10-05 04:30 PM

First off, what's your boost pattern? You should be getting some creep with the open exhaust.

Second, Knightsports typically tunes their ECU's for a particular car - you may not be running an optimal fuel/ignition setup for your mods.

I doubt the belt problem would cause a loss in power. Heat soak, most likely - that probably cost you at least 10-20 horsepower.

I'd also check for boost leaks. That's a HUGE power robber.

Dale

John Magnuson 05-10-05 04:59 PM

I rode in her car on Saturday at Mazdafest at Buttonwillow. It does run nice and smoothly so I don't think it's out of tune. She was getting used to the track and driving conservatively when I rode along so I didn't really get a feel for the power. Maybe a secondary boost issue?

Feesa, do you still get a little surge in power front the secondary turbo under full throttle acceleration when you hit around 4500 rpms?

Meiogirl 05-10-05 05:07 PM

my boost pattern is 10-8-10 sometimes i get 11 on the second.

creep is turbo lag or a sudden burst? my second turbo hits alot harder than the first.

i got it dynoed at the event in the buttonwillow garage pit area by the '7s only racing' guys. I dont see any correction on the read out i got so i dont know if it was SAE corrected. He didnt use a fan on the car and when i asked him if he would he said it didnt need it.

i figured those numbers were very low, i guess its time to look for leaks.

im prob gonna be up at that boba place around 8, see ya up there John.

Meiogirl 05-10-05 05:36 PM


Originally Posted by John Magnuson

Feesa, do you still get a little surge in power front the secondary turbo under full throttle acceleration when you hit around 4500 rpms?

yup, alot more so than i do on the first.

John Magnuson 05-10-05 06:25 PM

Using a fan is critical for good dyno results for a turbocharged and intercooled car.

If he didn't use the fan he's either:

1) An idiot

or

2) Lazy and didn't want to bother

As you can imagine your intercooler doesn't cool well at all if no air is passing through it. The fact that you had no airflow through your intercooler combined with the fact that you had just tracked the car for 20 minutes and were probably a bit heat soaked anyway makes it surprising that you even got 230RHWP.

I really wouldn't worry about the low dyno reading. If it bothers you a lot I'd suggest you go get another dyno done, with a fan, before you go trying to modify things.

I'll try to swing by Boba around 8

GoRacer 05-10-05 08:16 PM

I'd say both 1 & 2. You should have took your car off the dyno and asked for a refund since you sighned a waiver of liablility and he's not responsible. Pisston carnies shouldn't dyno rotaries.

I beleive the stock hp is 255 and add 10-20hp for the mid pipe. Was the previous dyno before the mid pipe? If my Greddy SMIC got heat soaked when I raced, then i'd imagine your OEM IC was worse. I'd imagine the M2 box gettin heated up as well and not any improvement since it wasn't scooping up forced air with the car standing still and the hood closed.

John Magnuson 05-10-05 08:40 PM


Originally Posted by GoRacer
I'd say both 1 & 2. You should have took your car off the dyno and asked for a refund since you sighned a waiver of liablility and he's not responsible. Pisston carnies shouldn't dyno rotaries.

Actually the car was put on the dyno at Mostly 7s facility. I think they're just used to non turbo rotaries... bridgeports and suchs. Without a turbo you don't really need the fan unless the car needs it for engine cooling. I think that most likely the guy was being lazy or in a hurry since it was a "Dyno Day" at the track and perhaps lots of people were paying for dyno runs.

diyman25 05-11-05 05:20 AM

MM... I think most important thing Is to learn how to drive your car fast.... YES you got some low Dyno power, but if you can drive it better, It will ber more important than Number. Hope you enjoy the track day....

Plus. A long as your car hold togeter this is most important thing in my opion.

dgeesaman 05-11-05 07:45 AM

I agree with John Magnuson. I think your intake was heat soaked. I did some dyno runs a couple summers ago on an almost stock car (dp only), and got 220rwhp. The dyno guys claimed they didn't have fans, and though I was pissed I was already on the ramp. So I did the pulls and by the 3rd one I was down to 210hp, and my engine was only just warmed up.

Dave

potatochobit 05-11-05 07:51 AM

your dyno numbers seem WAY low for your mods.

you say you are running a mid pipe? i see no way to go below 250 HP boost spikes without something not functioning correctly.


also i would never dream about running a mid pipe with no boost controller. i get 15 LBs spikes with a stock cat. unless your ECU controls it well, i have not heard much about the one u have.

POS7 05-11-05 07:57 AM


Originally Posted by potatochobit
your dyno numbers seem WAY low for your mods.

you say you are running a mid pipe? i see no way to go below 250 HP boost spikes without something not functioning correctly.


also i would never dream about running a mid pipe with no boost controller. i get 15 LBs spikes with a stock cat. unless your ECU controls it well, i have not heard much about the one u have.

Wow what are your other mods?

DaleClark 05-11-05 09:23 AM

That's what I'm thinking - there's no WAY you'd be running a 10-8-10 pattern with open exhaust and intake. That would be hard to get with a boost controller!

I'm starting to suspect a boost leak.

Dale

KaiFD3S 05-11-05 10:52 AM

she probably is not getting the boost spike since she is running the stock IC, would'nt that restrict it a lot.

Get an aftermarket IC and a boost controller and you should be at the HP you want to be at.

apneablue 05-11-05 10:59 AM

Actually, if I am reading this right. It doesn't seem she is really that off...

or maybe my car was FUBARed at the time too. but I dont think so because Chris at RP fixed my boost issues and dynoed me with almost the same mods she has.

I was running Intake / DP / Exhaust / Efini Y-Pipe / PFC
and got this

255 Dyno

Then I added a FMIC and resonated MP and got this

317 Dyno


EDIT...So she's a bit short about 15hp. Maybe 15hp could be factored in for heat soak from being at the track.

clayne 05-11-05 11:14 AM

That's way too low. I did 240 to the wheels with an exhaust and a downpipe only back when I first got my car. You should be doing atleast 250-260 to the wheels, minimum, with a mid-pipe. The only thing you can do is use a PowerFC and datalogging to see what actually is going on.

Also another dyno run would settle this.

Meiogirl 05-11-05 12:03 PM

wow, thanks for the further replies guys.

sounds like a good inspection for leaks and a cooler dyno run are my answers. i guess an intercooler and boost controller have been added to my list of future prospects as well. i think a PFC is a little much for where i want my car to be at.

i have never spiked or creeped. perhaps the KnightsportECU is keeping this from happenning?

iceman4357 05-11-05 12:07 PM

i didnt see a DP on you list of mods, that will help. Or if you have an aftermarket ECU, up the boost and tune it. I had a DP, mid pipe, intake, and a PFS shitty tuned for 13psi and ran 12's with it. Never dyno, but had to be around 270 to the wheels.

DaleClark 05-11-05 12:49 PM

When I first got my car, with JUST a cat-back and a downpipe (stock air box, stock air filter, etc) I got spikes when I hit the second turbo. I just can't imagine how you aren't spiking with your setup, or at least creeping to a higher boost.

I seriously doubt it's a restriction problem with the stock IC. If that was the case, you'd see LOTS of FD owners with stock ECU's and intake/exhaust not spiking and running a nice 10psi. That's just not the case.

Dale

clayne 05-11-05 01:30 PM

Yea, what it sounds like to me is a LEAK.

Anyways, presuming that you have a boost gauge, you need to relocate the vaccuum line for the source to the gauge to the turbo manifold and tell us what boost levels you see.

This involves using a plastic t-adapter that you can get at any Pep Boys, Kragen's, etc. for 2$. Connect this t-adapter, along with another piece of vaccum line to one of the nipples on the back of the turbo positive pressure intake manifold (y-pipe). Then move the vaccum for your boost gauge from the intake manifold to this t-adapter instead (obviously cap the nipple you just moved it from). If you see around 20+ psi here and 10 psi on your gauge, then you have a leak somewhere between the turbos and the intake manifold (not a 10 psi worth leak, but definitely a leak).

clayne 05-11-05 01:36 PM

http://robrobinette.com/efini.htm

Look at the first picture. It's an efini version, but for this discussion has the same nipples. See the two sticking out in the center? Use one of those with a t-adapter.


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