S54 Dyno Database

[Nick_P]

Stock cams?

Yes, stock cams. No other engine mods

[stash1]

Not sure if this has been posted in here, but here’s a recent dyno test of the ARH header system by Buildjournal:

https://thebuildjournal.com/reviews/...ts-and-review/

The data looks pretty consistent w/my own personal experience as well.

[fourmula1]

342hp on a dynojet
2003.5 dedicated track car ~93k miles...a lot of them on the track.
karb csl intake, catless headers, oem section 1 & 2, old agency power section 3
suspected fuel pressure issue...

If anyone has recommendations for troubleshooting fuel pressure issues in order of most likely culprits to least likely that would be helpful. Fuel filter under the car was just replaced. I'll replace the fuel pressure regulator next. Fuel pump after that?

[Anri]

Not sure if this has been posted in here, but here’s a recent dyno test of the ARH header system by Buildjournal:

https://thebuildjournal.com/reviews/...ts-and-review/

The data looks pretty consistent w/my own personal experience as well.

Stan,

I have not seen the ARH in person to compare the length
of the tubes to other brand headers. The longer the better.
From pictures looks like they are equal length and that is
a good thing.

ARH did something a bit wrong and reason for 5k rpm
and up of operation.

Regards,
Anri.

[stash1]

Stan,

I have not seen the ARH in person to compare the length
of the tubes to other brand headers. The longer the better.
From pictures looks like they are equal length and that is
a good thing.

ARH did something a bit wrong and reason for 5k rpm
and up of operation.

Regards,
Anri.

Hey Anri, I'm not 100% sure that they're actually even advertised as equal length or not-lol But yeah, as we all know now, it's a compromised design. Poor low-end performance w/some pretty good top-end w/the right tuning.😉

[DoubleSidedTape]

288/280 cams, Megan headers, everything else stock. Tuned by HTE.

[///Mangler]

Hey Anri, I'm not 100% sure that they're actually even advertised as equal length or not-lol But yeah, as we all know now, it's a compromised design. Poor low-end performance w/some pretty good top-end w/the right tuning.😉

Here is a quote and plot from my tuner. The loss of torque can be almost completely mitigated with a proper tune on a stand alone EMS.

"Make sure you have a pretty much open 3.5” exhaust, otherwise will lose huge power.

Here is a SSV1 complete, swapped over to the AR header (only change). Both tuned on same dyno, both by us, both on Emtron. Note – SAE number too."

[duracellttu]

Here is a quote and plot from my tuner. The loss of torque can be almost completely mitigated with a proper tune on a stand alone EMS.

"Make sure you have a pretty much open 3.5” exhaust, otherwise will lose huge power.

Here is a SSV1 complete, swapped over to the AR header (only change). Both tuned on same dyno, both by us, both on Emtron. Note – SAE number too."

Which curve is which?

[///Mangler]

Which curve is which?

Red is ARH

T

[stash1]

Here is a quote and plot from my tuner. The loss of torque can be almost completely mitigated with a proper tune on a stand alone EMS.

"Make sure you have a pretty much open 3.5” exhaust, otherwise will lose huge power.

Here is a SSV1 complete, swapped over to the AR header (only change). Both tuned on same dyno, both by us, both on Emtron. Note – SAE number too."

Would your tuner mind sharing what he's done differently (tuning wise) w/the stand alone vs. modifying factory maps, to retain low-end torque? Also, keep in mind that a proper stand alone set up can run into the $3k plus range, and while it's pretty awesome...99.9% of folks will never go stand alone-for that reason.

[ZiMMie]

Here is a quote and plot from my tuner. The loss of torque can be almost completely mitigated with a proper tune on a stand alone EMS.

"Make sure you have a pretty much open 3.5” exhaust, otherwise will lose huge power.

Here is a SSV1 complete, swapped over to the AR header (only change). Both tuned on same dyno, both by us, both on Emtron. Note – SAE number too."

What other mods does the car have?

[///Mangler]

Would your tuner mind sharing what he's done differently (tuning wise) w/the stand alone vs. modifying factory maps, to retain low-end torque? Also, keep in mind that a proper stand alone set up can run into the $3k plus range, and while it's pretty awesome...99.9% of folks will never go stand alone-for that reason.

This is why you pay good $$ for a real tuner and a high end stand alone EMS. The one on the car with the dyno above is way more than $3k installed and tuned. You get what you pay for.

as for the other question about the mods, its a stock motor with airbox and the headers/exhaust that are listed. That's it.

T

[stash1]

This is why you pay good $$ for a real tuner and a high end stand alone EMS. The one on the car with the dyno above is way more than $3k installed and tuned. You get what you pay for.

as for the other question about the mods, its a stock motor with airbox and the headers/exhaust that are listed. That's it.

T

Uumm, a lot of us do use “real tuners”, so not sure what the implication is there? And yeah, I kinda figured that the stand alone you’re running is well north of $3k…I was being a little conservative on purpose.😊 Again though, I was just wondering what parameters exactly your tuner changed to recoup the low end torque loss? AFR trims and timing are fairly easy to do w/a factory ECU…and 1/2 pt of fuel or a couple degrees of timing here or there aren’t going to recover that much torque. Of course there’s also cam timing to play with, but you can only compensate so much w/VANOS adj's.

These headers just don’t seem to flow well under 4k rpms, and every single graph that I’ve seen to date seems to reflect that…everyone is pulling fuel at low rpms. You can’t make power if the airflow isn’t there to support it.

[digger]

This is why you pay good $$ for a real tuner and a high end stand alone EMS. The one on the car with the dyno above is way more than $3k installed and tuned. You get what you pay for.

as for the other question about the mods, its a stock motor with airbox and the headers/exhaust that are listed. That's it.

T

You dont need an uber dollar ecu for a NA S54 that is mostly street driven. Tuning WOT is the easiest part to tune, there are only so many variables to change and optimise that actually affect torque/power. There is no magic / secrets with tuning that standalone brings to the table its just about how much experience the tuner has with each variable and how much time/$$$ the customer is prepared to pay to optimise everything as AFAIK the stock ECU gives you access to all parameters that are going to affect WOT but just in a more cumbersome way making the process less efficient than a aftermarket ECU. Personally i would go standalone so you aren't limited to a couple of tuners and in the long run it might be cheaper as many things can be DIY

All the other non WOT stuff is where the skill/time goes is and why keeping the OEM ecu has some fairly big advantages on a mild spec engine.

[digger]

Uumm, a lot of us do use “real tuners”, so not sure what the implication is there? And yeah, I kinda figured that the stand alone you’re running is well north of $3k…I was being a little conservative on purpose.😊 Again though, I was just wondering what parameters exactly your tuner changed to recoup the low end torque loss? AFR trims and timing are fairly easy to do w/a factory ECU…and 1/2 pt of fuel or a couple degrees of timing here or there aren’t going to recover that much torque. Of course there’s also cam timing to play with, but you can only compensate so much w/VANOS adj's.

These headers just don’t seem to flow well under 4k rpms, and every single graph that I’ve seen to date seems to reflect that…everyone is pulling fuel at low rpms. You can’t make power if the airflow isn’t there to support it.

there isn't much beside fuel quantity, injection timing, ignition timing, coil dwell, vanos inlet/exhaust positions, throttle position (i.e not going 100% at WOT), not much in the way of power in optimising per cylinder basis though less likely to burn the engine up from heat/knock. As you say there is only so much you can counter fundamental reversion issues via software changes.