devious12

I went to Mustang Magic and had the car on the dyno for 2 pulls. After I was traveling about 10 miles the first pull was made and it was 181.0. We let the engine cool for about 10 mintues and pulled again this time 191.0. The conditions were slightly cool outside, 93 octane, no cat B&B straight pipe, B&B catback, K&N intake, and the LSD turn all of the way off, also I had a check engine light which they Joe said could definatly effect the numbers in a negative way if the car is running too rich, and I know it has to be running to rich because I haven't had the car tuned after I took the cat off and added the K&N. I do more pulls on the same machine over the winter after I do some mods to the engine. No, I didn't dyno the car when it was bone stock, I know I should have, but at least I know where I stand now.

r0tor

iTrader: (1)

peak power should have been closer to 8000 rpms, so yea it does appear the ecu was holding back in the upper rpm range and you would have made more power.

rotarygod

I want someone to find a way to make a note of the water temperatures at the time of their dyno pulls. I want to see the differences between runs. I want to find a corellation between heat (coolant) and power.

bryrx804

was the cell on before the dyno or did it turn on during the dyno..?

brothervoodoo

CEL or flashing DCS light.....

Good pulls even with CEL...

zoom44

the charts are off. the HP and T lines cross at the wrong rpm.

monzter

Thats what I was thinking..shouldn't they cross alot sooner? 5252rpms I think. Unless there's some sort of plotting error or something else I'm not grasping.

mysql101

what did the dyno cost you?

RX8-TX

Different scales for hp/tq :D

BaronVonBigmeat

Err...what do you mean by "different scales"? The dyno just measures torque and then calculates HP right? They should always cross at 5252.

devious12

Listen I don't know much about the dynos, but I do know that the cel was on before both of the pulls do to the fact that I have no cat. The 2 pulls cost me 100 bucks. 75 for the first and 25 for each additional pull.

Please explain how this chart is off because I do not know much about the way a dyno correctly runs.

Thanks

PoorCollegeKid

The chart is fine. At 5252rpms, torque will always equal horsepower. If you graph torque and horsepower using the same scale, then the torque curve will cross the horsepower curve at 5252rpms. However, on this graph, the torque and horsepower curves are graphed using differing scales. If you look where it says 100hp on the left side of the graph and draw a straight, horizontal line over to the right side of the graph, you will see that this line roughly coincides with the 75lbft of torque mark. This is what is meant by different scales. Now, if you look at 5252 rpms and find the value of each curve at that point, you will see that both torque and horsepower are ~125, which is as it should be.

To sum it all up, your graph is right, those who believed that it was wrong simply forgot to look at the relative scales of horsepower and torque as those curves are graphed on your print out.

devious12

Thanks, good explaination

bureau13

Why would you be running rich with an intake and exhaust? Shouldn't that tend to lean you out?

jds

devious12

I would only think that the engine would run rich because there is not cat on the car just a straight pipe, also the smell of the exhaust is horrible, eye burning, and most of the time when I shift (when racing it) flames blow out the back. I know some of that stuff is normal for rotary but only to a certain extent? right?

I'm not completely sure, I'm no expert, really just guessing because I didn't get the a/f ratio reading.

Let me know if I'm wrong, I'd rather someone tell me how it works than to be wrong and sound stupid.

I can tell you that I had the K&N on before I did the exhaust, and it ran rough, now after I opened up the exhaust with the straight pipe and catback, it seems to have balanced it more, or it's all in my head.

Relentless

How did you dyno it?

We tried and had some problems, as the ECU knows that the front wheels aren't moving and would brake the engine at about 150 hp and 6000 rpms. Wondering how to get around it.

devious12

I don't know they didn't seem to have any problem with my car. I do recall him asking me to turn off the DSC totally before each pull, I don't know if that really has anything to do with it.

Maybe someone who has more experience with this can answer it better.

bureau13

I know with my previous car, opening up the intake and exhaust would make it run lean....better airflow, same fuel. However, come to think of it, that was not a MAF-based system. I would assume the stock ECU would act to keep the air/fuel where it expects it to be based on your MAF readings, so you should probably be roughly the same mix as stock? Which is indeed rich up top. So never mind, you're probably right, although I doubt you are actually *richer* than stock.

jds

RX8-TX

I meant that the 'grid' for Horsepower maxes at 200, whereas the 'grid' for Torque maxes out @ 150.

Follow the hp curve to 5252, note the hp value. Then follow the Tq curve, and note its value at 5252rpm. They have the SAME value, different unit.

zoom44

thanks for the explanation. note that i didnt say the info was incorrect only that it looked like the graph was "off". thanks to the info and a second look at the graphs i stand corrected

Mr. Ed's rx-8

i have the same set up on my car(just greddy exhaust instead of B&B) but i have the same mid pipe with no cat. i just got my O2 eliminator wired in and and the car seems to have leaned out a little. i'm still shooting flames out the exhaust but not nearly as bad. i need to get mine on the dyno see if it pulls about the same.

devious12

Hey Mr. Ed what O2 eliminator did you use? Thanks I need to get one. If you can post the model number and the website please.

Mr. Ed's rx-8

i got mine through my buddies shop(gothamracing.com). i beleive you can order one through casperselectronics.com but you need to keep your stock o2 sensor and splice the eliminator into it. just keep it all zip tied up out of sight. i plugged my test pipe and now my CEL light is off after resetting the battery and my car has a little more pep to it. like i said though it still is shooting flames which leads me to beleive it is still running a little rich.

KTune3

These dynos are probably why I wont get a RX8. I have a base RSX and I'm buying a new car soon that is faster. The RX8 and RSX Type S are the front runners. The only problem with my car now its low torque which sucks at low RPM till the HP kicks in. Now I see that from these dynos that the RX8 has even LESS torque than the RSX until 6k rmp. This is a no no. I guess I'll see for sure when I test drive a RX8 but this doesnt look promising I really would want the more upscale RX8 because its more exclusive but the gas mileage and its shitty torque might put the nail in its coffin.

rotarygod

If you are only basing your buying decision on power, why in the world do you want an RSX or any Honda product for that matter? There are so many other more powerful cars out there. Instead of looking at numbers, go DRIVE ONE. Numbers mean NOTHING when comparing other cars. There are too many variables. People that actually drive one always comment on how they don't understand the lack of torque complaints that people have. It doesn't feel like it. Compare the RX-8 to an S2000 and you'll understand. The S2000 is a gutless wonder until you rev it way up. The RX-8 unlike the S2000 actually has usable power everwhere else in the rpm range. You won't make me believe that the RSX engine is better than an S2000's. If you only want power, buy an LS1 Camaro and avoid Honda like the plague. If you actually want a car because of how it performs in the real world and not on paper, go test drive an RX-8. Until you've driven one, you have no right to insult it.