pdxhak

iTrader: (2)

Is it a motor built by BDC? Based on the WHP I was thinking the irons he recently ported but you said stock irons.

colombian8

I wish I knew more about tunning. I understand what the graph is used for. Are we trying to figure out what mods the car has?

MazdaManiac

iTrader: (3)

These are GrandAm cars. No porting or internal engine modifications are allowed.

pdxhak

iTrader: (2)

Well he did not say the motor was his or for racing. I'm just taking a stab in the dark...

colombian8

So my question is what is the question... are we trying to figure out how obtained 160 tq between 8000 and 8500 rpm?

MazdaManiac

iTrader: (3)

I don't think there is a question. There is nothing to "figure out".

Eric has a well built engine that made a ****-ton of torque and power (for an NA, restricted-build Renesis) using the same sort of tips/tricks that all the GrandAm teams are limited to.

For those of us that had the opportunity to tune those cars, anything over 225 was happy time, but 230+ was payday.

colombian8

Ok that makes sense. i thought the RX8 had 230 stock. I guess i have a lot to learn. I did figure the torque was high though

RotaryMachineRx

iTrader: (1)

^You have a lot to learn grasshopper.

Highway8

iTrader: (11)

Stock claimed HP was 236 but that was flywheel. 15-17% loss in the drivetrain makes claimed RWHP around 200. Most stock cars dyno around in the 170-185 RWHP.

Silver6

I wish it had 230 to the wheels stock. But unfortunately we do not...

Reaver

iTrader: (1)

I'm on the edge of my seat, I'm guessing he won't tell all because it would allow others competing to copy his hard work and remove his edge over the competition? Very impressive numbers.

EricMeyer

Let's try this again. The chassis dyno sheet offered in post #1 captured on a dynojet is a non-ported Renesis. Non-turbo and non-supercharged. How did these big numbers occur?

There are several assumptions here that people are throwing around--a bit like those in a Who-Dunnit mystery who talk out loud and people believe them. On the other hand a few of you are stating the right things. Put them in the form of a question and some of you will get there lickity-split. It's the ole' outside the box thing. Try using the Socratic method and you'll colectively figure it out quickly.

The question is this: How did a stock Renesis make this much power?

EricMeyer

Good guess but no.

EricMeyer

Not built by BDC

Highway8

iTrader: (11)

You have spelled it out in other post like this one. https://www.rx8club.com/showpost.php...3&postcount=71

Baiscly you build a good motor, with new or mostly new parts, balancing the rotating assmebly and the fuel injectors, a few oil and coolant flow tricks to improve longevity, Use a high flow intake, long tube header, tune it for the spec 98 race fuel (Probably the .93 Lambda aka 13.5 AFR). Break the motor in and then make your dyno pulls. Run it in 5th gear to make the most power.

Brettus

iTrader: (2)

That plus special ingredient 'X' .

MazdaManiac

iTrader: (3)

I was unaware that "meticulous" had and "x" in it.

skc

If I shift to 5th gear then I loose on my lap times as the RPM drops to around 6000 and I also loose a bit of momentum so close to a 3rd gear corner. So this is why I keep redlining until I reach a speed of 198kmph in 4th gear.

I believe the extra HP and torque with a SC will allow me to shift to 5th gear and less strain on the mechanical components. This is only a theory and once I have converted only then I will be able to find out the benefits of any on my lap times and how reliable the system will be. I will have to learn to be less aggressive and show more mechanical sympathy.

Reaver

iTrader: (1)

So non-turbo and non-supercharged but you don't say anything about nos. Did you use nos?

Edit: I guess the guy up a few posts got it nailed by finding one of your previous posts. twas fun while it lasted

skc

All this plus having a reliable source of fuel will allow you to tune the engine to its maximum potential.

skc

It is also interesting to note that the power curve says fairly flat once it peaks. This must be due to the good exhaust.

Brettus

iTrader: (2)

Just for fun - here is Eric's dyno as compared to a relatively strong stock dyno and a Greddy turbo on stock waste-gate with no boost control.

laythor

It boggles the mind to think how much research, testing, dyno time, and tuning go into getting that extra TQ and HP.

Makes me very happy to have the numbers I get from my mostly stock NA.

Highway8

iTrader: (11)

Have you topped 190 yet?

PhillipM

Probably, mine's similar with the really long headers, the power curve is basically flat for nigh-on 1krpm up top.