Hey, a local shop was having a cheap dyno day, so I took my car in and did 2 runs.

My car is stock, the only real 'mod' is that I removed the VFAD duct, other than that nothing is changed. The engine has 8500 miles on it.

We ran the dyno in 5th gear (1:1) and it made 165whp/140wtq. We did the 2nd run in 4th gear and it made 163whp/138wtq. I will post the dyno graph later when I get a chance to scan it in. I was suprised by the tq, but thought I would make a bit more HP, I was thinking it would be in the 175whp range.

My girlfriends '03 RSX TypeS (injen cold air intake otherwise stock) made 170whp/134wtq on the 1st run in 4th gear, and on the 2nd run I tuned her VFAC and it ran 175whp/136wtq)


Its a Mustang dyno and it was about 89*F out, moderate humidity and elevation is about 50ft above sea level.

 

I will also post that even with the DSC off, the car was having a hard time reving over about 7K rpm, felt like timing was being pulled, or the car wasnt letting the throttle open 100%.

On the street the car pulls good in all gear, on the highway 5th gear pulls from 4k-9k (same thing we did on the dyno) take about 15secs less time, and the car will pull smooth all the way up to about 150mph. On the dyno the car started to struggle to get ever other MPH out.

Anyway, I dont care much about the dyno numbers, Im happy with the performance of the car.

 

why did you remove the vfad duct?

 

^Yeah. But if that is indeed a Mustang dyno, you did pretty good.

 

Yeah, if it's a Mustang dyno your numbers aren't really off compared to other owners.

 

So What would he have got had he been on another dyno?

Or is it just something he'd have to try out and see?
________
How to roll a joint

 

All dynos are calibrated differently so you can't really give an exact figure. All cars are a little different as well... However, on a dynojet his numbers probably would have been around 180 give or take 5whp.

 

yeah, Im not sure how this dyno was calibrated, another car that went said his car did 230whp on a dyno jet last week and did 207 or something this week, so about 15whp less (corrected) so I would guess I would be about 170-180 whp range on a dynojet, and thats about what other owners are getting, right around 180 seems to be the norm.

At the same time, a lot of other RSX TypeS owners dyno 180-185 on dyno jets with the same mods as my girlfirends car, and she did 170 on the mustang dyno.....so thats about the same 15ish whp off.

I was supprised by the TQ, 138/140 wtq.....I thought it would be more in the low 130s/ high 120's but Im happy.

Thanks to the racing beat breakin and premix in my fuel tank!

I wonder if I would have picked up any power if I reset the ECU? Also the AFR was pretty rich (as usualy) I might be able to pick up 5-10 whp if I could pull about 1.5 points out of the AFR and run about 13-13.5 AFR accross the board.

I was also pretty happy that 45 secs of WOT and the car didnt overheat or anything sitting on the dyno with that baby fan....

I took the vfad duct out case it was broken (cracked in half) when a car hit me in a parking lot. So I figured I would just leave it out. Plus the car sounds better without in IMO.

 

Mustang dynos always read low. Unfortunately for me, the only Dynojet in El Paso is run by a pack of children (see my dyno nightmare thread in the aftermarket section for details) who have no idea what they are doing.

 

yeah, we have a dynojet here at work, so one night this week I will run a pass on the dyno jet to see what the numbers are. From then on ill use the same dynojet at work to run the car, so I can have the same dyno to compare baseline to mods....ect.

 

how about hooking another CFL rx8 owner up

 

If you have a Dynojet at your owk why didn't you just use that in the first place?

 

 

lol well at work our wideband o2 is broken, plus I cant do friends cars and stuff for free, a couple of my friends were going to this shop, and it was only 20 for 2 pulls, so I figured why not, I end up spending 30+ everynight I go downtown, so Ill just skip out this week and end up saving money...lol

It was fun, and I can run on a dynojet anytime, but i have to pay to run on a mustang.

I am gonna get some baseline #'s on the dynojet at work this week one night....and then Ill keep using the dyno at work to compare before and after, so it will be a little more accurate.

Tommorow Ill scan in my dyno sheets from the mustang, and add the dynojet sheets later.

 

I though a dyno pull is best done in the middle gears, why 5th?

Regardless, I wonder if there is any truth to the renesis not showing well on dynos because of electronic nannies...I heard to combat inherently excessive catalyst temps, any excess wheel slip causes it to retard power to avoid higher temps, even with a full DSC shutoff.

Either way, it should not show less that a relatively stock RSX-S.

 

A stock RSX Type S dynos at nearly what an RX-8 does, plus an intake on those cars can add 10+whp.

 

ky,
let me know when you are going to do the next one.

beers

 

gear ratio is 1:1 in 5th

 

The rsx being FWD has less 'drivetrain loss' than the RX8, so they both will dyno about the same HP stock. My car is still stock while hers has an intake, common power increase with an intake on those cars (as ike said) is in the ~10hp range.

As far as electronic problems, yes there are obviously some with the rx8 on a dyno. I know the car has more power than it shows at a dyno cause for a 3000+ car to run 95mph in the 1/4 mile you need at least 200-210whp.

If you were to dyno the car with the DSC system on, it would apply the brakes to stop the rear wheels spining and would cut the throttle input, to let the RPM drop.

Even with the DSC off, after the wheels spin up to ~5mph+ the ABS light comes on, this could be causing something in the ECU to freak out....im not sure.

Also as you said as the EGT temps go up, the car dumps in more fuel and retards the timing, the car wouldnt even rev over 8k rpm in 5th gear, I know I can take 5th gear over 9k as I have done on the highway a few times.

You want to dyno a car in the 1:1 gear, or as close as possible to that, so that the WHP (wheel horsepower) reading is as close to what the engine is putting out, caues the gearing in differnt gears can affect it.

Anyway, I would much rather have the car making full power out on the road than on the dyno.

 

as it turns out, the HP/TQ figures on these dyno's is UNCORECTED. After talking to the shop, my CORRECTED number is 169whp on the 5th gear pull and 163whp on the 4th gear pull.

5th Gear


4th Gear

 

The 5th gear run was cut off at about 7900 rpm and the 4th gear pull was cut off at about 8200rpm, as the car didnt want to rev any higher. I was also getting quite a bit of blowby and lots of oil out the exhaust after 45+ secs of WOT, but the car didnt go above 220*F coolant temp.

Does anyone know where the best place is to get an rpm pickup, we tired and tried to get it off all 4 of the plug wires coming off the coil packs, but the signal was droping in and out.

 

This is the first time I've heard somebody say FWD has LESS drivetrain loss than rwd...weird.

RWD - especially RWD with a rotary engine and light-weight components (CF Driveline) - should 'eat up' less available engine power, as the motion direction is only changed ONCE - at the rear-end differential.

 

That is one weird dyno... Time based? Doesn't tell you much does it? All I see is a nice flat torque curve.

 

Most cars that have ABS, the light will come on when you are on a dyno because of all the wheels not moving together, did this in my old SVT Focus I had. I think you are right, the electronics on the 8 definantly do not like to be on a dyno.

 

Just wanted to add what I have been told on this forum, that most people are using 4th gear because you will have less heat bulit up by the time you are ready to run in that gear, instead of 5th.