Sharif@Forged

iTrader: (92)

We also have the single retarder 450. It had stead state 600whp, and measure 1200whp. Thanks.

We do tune the Split Second boxes. It's not a bad system, but there are better offerings out there...such as the UTEC.

El Verdugo

Thanks for the quick response, yes you are the third tuner that tells me about the UTEC. Must be that good of a system, had not had a chance to install or tune one yet.

I just brought it up since there is a client (G35 with Vortech SC) that asked me if I could tune this system for him. We have done other standalones, so looking at the SS GUI does not seem too bad. As long as the SS box follows my command and does not act crazy or stubborn.

datsunscom

Sure, but you're not going to make a big turbo show that it's spooling sooner than reality are you? If 3.5L isn't spooling a T88 by 4000RPM I don't see how you can load it to make it look like it spools sooner, then again I'm no dyno expert. I know you can make the absolute numbers read pretty much what you want but I figured changing the shape of the torque curve would be a different animal.

Also if they preload as you stated wouldn't the torque curve have a funny bump in it (as seen clearly in dyno pulls where you run through the gears instead of a single gear pull)? Dunno.

In any case it sounds like we're back to the "just stick to one dyno and use it just for tuning" that most of these comparo threads end up at.

Dave Lum
www.datsuns.com

Sharif@Forged

iTrader: (92)

^^we dont manipulate our dyno runs...but my point is that its easy to do^^

Turbo spool is driven almost entirely by engine load..not RPM. It's the same concept as brake boosting, or using a two-step launch control. If I were to load my dyno (Steady state), and mash the pedal, I can built 10+psi of boost without actually recording or releasing a run. So once I release it, the trq curve will look like a monster down low...there will not be spike, as the peak trq will remain the same. Does that clarify it for you?

doug

iTrader: (5)

sweet area under the curve

NTRIGUE

Thanks for the research GMAN.

The DYNO is a valuable tool for effective tuning of one's modified Z. By analyzing A/F ratio, torque curve, peak horsepower, and peak torque we can make a much safer more driveable Z. We can also track the progress of our modifications from inception to completion only by eliminating as many variables as possible; these include but are not limited to temperature, humidity, A/F ratio, and altitude.

If you intend to play into the testosterone game then find a dyno at sea level on a chilly day and make it a dyno jet; heck just SAE correct it at 13%. You will have the higher numbers and in turn the larger manhood.

But, if you intend to build a flawless performer and develop consistency in track runs then stick to one dyno Mustang, Jet, Dyno Dynamics, whatever it may be.

doug

iTrader: (5)

nevermind...

El Verdugo

Well said, the true numbers is on the grin of the driver after his investment is running great and at the track when the ETs are much lower.

ronald_m

Out of topic. Any input on Dynapack dyno?

Bullitproof

iTrader: (3)

My car was tuned with a dynapack and they used a fan to simulate airflow. i went to a mobile dynojet with no fan and my numbers were 20whp less in the same weather. i only did one run on the dynojet, so it wouldn't be a fair comparison to the runs on the dynapack. i know i am making over 400whp, how much more, who knows? I'll probably throw some drag radials on it in the fall and try to lay some times down.

datsunscom

I understand what you're saying yes. It's the same reason you can rev the engine to 6000rpm in neutral and get no boost (all RPM, almost zero load).

Dave Lum
www.datsuns.com