Engine mods

[Operation.stinger]

Hello everyone! I’m looking into upgrading a few things to give a little more power but also keep reliability and to stay safe but don’t know where to fully start. Anything helps!

 

[ChaneRZ]

Jb4, plugs, exhaust. Maybe tcu tune down the road.

 

[rtv900]

a mild tune is the easiest way, and easily reversible. But it has to be really mild if you want to keep it reliable.
You can't bump up to 18psi of boost or something.
2 above stock would make a noticeable difference but not be too hard on it.

 

[Thomby]

a mild tune is the easiest way, and easily reversible. But it has to be really mild if you want to keep it reliable.
You can't bump up to 18psi of boost or something.
2 above stock would make a noticeable difference but not be too hard on it.

18psi should be something like JB4 map 3, which I think plenty of people are running (on E30) without issue. For that matter, lots of people running maps 4-5 which would be about 20psi.

 

[drob39]

a mild tune is the easiest way, and easily reversible. But it has to be really mild if you want to keep it reliable.
You can't bump up to 18psi of boost or something.
2 above stock would make a noticeable difference but not be too hard on it.

What would +2 put it at?

 

[rtv900]

What would +2 put it at?

I don't know for sure. I'd guess 20-30 hp, which will be a meaningful increase.
Not like the "20hp gain from a cold air intake" or some nonsense like that.

I'm just surmising based on the factory engine making around 375 on 15psi atmosphere plus 10-12 in boost, so 25-27 total PSI.
which means around 15 or so hp per PSI.
That isn't going to translate exactly as you add boost, but it's a pretty accurate estimate for a rough idea.

 

[Thomby]

Assuming this is still up to date, the mildest map that BMS/JB4 offers, designed to be safe for 91 octane, adds 4psi down low and 2.5 up high. And I think that's considered to be good for around 30-40hp.

Kia & Hyundai JB4 - JB4tech.com - International Turbo Tuning Discussion

*** We're going to use this thread as the general Kia Stinger informational thread including posting the install guide, mapping guide, software, firmware updates as we release them, logs, and general discussion. *** Order Here! (http://www.burgertuning.com/kia_stinger_jb4.html) Use subject to...

www.jb4tech.com

Map guide as of v15+ firmware (selected via JB4 Mobile/laptop interface. Map1 is the default map)
Map 0: JB4 disabled
Map 1: 4psi over stock peak tapering to 2.5psi at high RPM. Default performance map suitable for all 91+ octane fuels.
Map 2: 5psi over stock tapering to 4psi at high RPM. Suggested for 93+ octane fuel.
Map 3: 6psi stock tapering to 5psi at high RPM. Suggested for high quality fuel including unleaded race gas, ethanol mixtures up to 30%, or high quality octane booster like Torco or Boostane.
Map 4: Up to 7psi over stock. For use with unleaded race fuel and/or E85 mixtures up to 30%.
Map 5: Up to 7psi over stock but without top end taper. For unleaded race fuel use and bolt on modifications. May not be suitable for E85 mixtures due to high fuel pressure dropping. If using this map on E85 you should be experienced at reading your own logs and evaluating ignition advance and fuel pressure.
Map 6: User adjustable map. Enter value of boost over stock by RPM on user adjustment page.
Map 7: Progressive WMI (water/meth) map. Increases boost as a function of methanol flow & methanol boost additive. Holds boost low until WMI is flowing to avoid tip-in knock, and reduces boost as a function of WMI flow in the event of interruption like running out of fluid, leak, or component failure.
Map 8: Valet map, runs around half as much boost as stock.

 

[ExtremePowerHouse - MIke]

When you are working within the turbo's efficient range, every PSI will add ~ 15 whp

once you start pushing too much boost, the return will start diminishing

 

[drob39]

When you are working within the turbo's efficient range, every PSI will add ~ 15 whp

once you start pushing too much boost, the return will start diminishing

What do you consider too much? And is that when you move to bigger turbos?

 

[rtv900]

What do you consider too much? And is that when you move to bigger turbos?

yes, bigger turbos, but you'll trade off the awesome spool of this car for more lag and top end
bad move IMO
you could easily add 6-8 psi without pushing these turbos

 

[Thomby]

yes, bigger turbos, but you'll trade off the awesome spool of this car for more lag and top end
bad move IMO
you could easily add 6-8 psi without pushing these turbos

Do you have any examples of turbo swap cars and their subsequent power curves? The couple of anecdotes I've seen don't seem to be much ahead of what a dialed-in stock car will do with ethanol and WMI/CPI, and I suspect it's due to the severe restriction in the exhaust manifold/turbine housing.

I'm no fan of big laggy turbos that don't spool til 3500 rpm, but given that ours kick in at 1300 (ie the slightest roll onto throttle to climb a hill), I wouldn't mind giving up say 500 rpm in spool if it meant turbos that kept building power from 6-7000 rpm and let me hit 600hp+. I just don't think that's likely without a freer flowing manifold/housing...but happy to see otherwise.

 

[rtv900]

not other than the endless supply of examples online
I'd never swap these turbos. IMO they're set up for perfect streetability. Awesome low end and taper off at the top.
I don't know how you get to 600+ without giving up every bit of the bottom end.
Plus personally I don't think this platform can handle anywhere near that power level

 

[Thomby]

not other than the endless supply of examples online
I'd never swap these turbos. IMO they're set up for perfect streetability. Awesome low end and taper off at the top.
I don't know how you get to 600+ without giving up every bit of the bottom end.
Plus personally I don't think this platform can handle anywhere near that power level

Fair enough, I guess I figured there was plenty of room between stock 1300 spool and 3500 "big turbo" spool, ie something that kicked in around 2000.

But the upgrades I've seen seem to be either "coming soon" from 2 years ago, or "up to 700hp" with 500 on the dyno but more to come etc. Anything out there that shows where the Pure Turbos spool and max out? All I've found is a grainy Tork dyno that looked like they spool maybe 200rpm later and add 75hp/50tq, but off a pretty low base that I assume was from a few years ago before people really got the most out of stockers...

 

[drob39]

I feel like the only way to get to low 11's quarter mile is the same formula pretty much everyone uses:


ECU
TCU
E85/E30 with WMI or CPI
Exhaust
Plugs

 

[ExtremePowerHouse - MIke]

What do you consider too much? And is that when you move to bigger turbos?

Too much depends on each turbo, a few PSI are well within the stock turbo efficient range.

If you cross that range, a bigger turbo would be the next step