Can Someone Explain My Tune? Out Of Puff?

[Rekin]

Hello all,

Just wanted some input on my tune...

Back in 2008 I had my car tuned with HKS2530 @ 15psi & ARC sidemount intercooler

The results shown below: 207.9kw @ 11.5afr

Just recently had my car retuned with HKS2530 @ 19psi, retarded exhaust cam by 8degrees & Apexi Front mount intercooler

The result shown below: 207.8kw @ 11.5afr

Both tunes conducted on the same dyno / mechanic??

Could anyone help explain why there was no power gain when increasing boost? Does it look like a restricted intake / exhaust? or does the turbo top out at 15psi?

Ive found some quick info on the turbo...

===================

HKS GT2530: uses compressor of T3 63 trim, flows a little more but slightly less efficient than the T3 60 trim.

Compressor Map:

30LB/Min or 434cfm @ 2PR @ 65% efficiency.

32LB/Min or 463cfm max flow @ 16psi.

28psi max boost limited by compressor wheel speed.

===================

Thanks for the help

[AngryRB]

there doesnt look like theres much increase in boost, looks like 16psi in both at redline

[ARTZ]

to be fair it has made the power earlier throughout the entire midrange though...it seems up a little everywhere...adding more boost will often add more to midrange power, but no effect top end too much. depending on the turbo of course but you can put 2 bar through it and it might not make more power but it will pick up a little in the midrange....if you notice your 207kws is in some 300rpm sooner..

basically if you want more power get a bigger turbo or fill the tank with e85, but I imagine from looking at that chart the car is faster now than it was before regardless of the peak power output

**looks like your old ARC cooler was doing a perfectly good job too

[scotty nm35]

Needs moar Hypergear...

What did Trent say?

[sickr33]

How is the boost controlled?

The boost curve is much nicer in the first graph Nice and flat with slow creap!

The second graph looks nice but the falls away too early for my liking so as menchioned only running about 16psi in the top end!

Maybe the exhaust cam has been retarded too far? Causing it to be really strong in midrange but fall over too early! Maybe 6deg and if you could hold the Higher boost too the red line that power figure would grow?

But as said the second tune would have more useable power!

(I am not a tuner just my personal opinion!)

[Rekin]

Thanks for the comments.

First tune was using a bleed valve on stock actuator.

Second tune is an adjustable actuator.

The car does feel much faster. However boost is hitting 19psi without much power increase but has all the risks involved in running higher boost?

Tuner reckons intake pipe could be restricting flow, although hasn't been proven yet.

Surprised how well the arc sidemount did. (Could have kept my foglights & auto front spoiler too )

Thanks

[scotty nm35]

Stock intake? They suck shut at around 200kw unless you slide a bit of 3 inch pipe inside them...

[ARTZ]

What does it matter if there is a power increase ?

if the car is faster you're winning...

edit*

Ok quik browse through rb20 thread shows it should be making around 230-240 yeah..

[Rekin]

Stock intake? They suck shut at around 200kw unless you slide a bit of 3 inch pipe inside them...

Yeah that's what I'm feeling could be the issue... Will add a 3inch pipe inside on the weekend

[Rekin]

What does it matter if there is a power increase ?

if the car is faster you're winning...

edit*

Ok quik browse through rb20 thread shows it should be making around 230-240 yeah..

Yeah was expecting around 220+ hence the worry, else would have stuck to 15psi and sidemount.

Also found it interesting how both tunes were identical peak power 4 years apart haha

[copycutter]

What are the inlet temps with that sidemount? That 210 alone is impressive in my book for a side mount intercooler. What are the ARC sidemount's dimensions? I'm guessing decently thick but still rather small length and height wise.

[Rekin]

What are the inlet temps with that sidemount? That 210 alone is impressive in my book for a side mount intercooler. What are the ARC sidemount's dimensions? I'm guessing decently thick but still rather small length and height wise.

Its a big boy but no doubt it would heatsoak after repeated use. An fmic would provide better temperature though.

ARC m105 - 105mm thick

[copycutter]

Are you particularly averse to the idea of getting a bigger cooler?

[GTSBoy]

He already has a bigger FMIC compared to the old run.

[Plattsy]

if you have that arc sat in the garage give me a shout lol.

[copycutter]

He already has a bigger FMIC compared to the old run.

Sorry my mistake, didn't read properly.

If the intake to the turbo, or the exhaust system aren't restrictions, and it's not the exhaust manifold, then maybe you'd have to have a look towards engine compression & then leakdown test to make sure the engine's healthy?

Not making power per extra psi of pressure sounds more like intake/exhaust restrictions though.

[sickr33]

Also what exhaust do you have? 3" all the way? Cat?

Some people don't agree but I install a decat pipe when ever I do exhaust upgrades.

I find the car seems much more rev happy with out them! Assuming the rest of your exhaust is good!

You can get silicone intake pipes for about $60 of eBay might be something to think about?

Filter is it a good brand? And clean? You would be surprised at how much hp you can loose with a dirty one!

These are the things I would check first and then play with the boost until it holds 19psi to redline

[AngryRB]

its only running 19psi in the mid , theres hardly any change to the boost at the redline, hence you get the same rwkw?

Maybe get an ebc and set it up for 19psi at redline , and add the 3inch steel intake pipe, although im not sure that turbo is happy with much more than a bar is it?

Edited March 15, 2013 by AngryRBGTX

[Missileman]

I could use that side mount for my 32, is it for sale?

[DVS JEZ]

Rb20's just dont seem to be making power lately. Time for rb25