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Thanks, I need to get the windows tinted like yours! I got my JB4 on Amazon $619 ($479 JB4, $140 Bluetooth). Buy with confidence - it every bit as easy to setup and use as everyone says. I ran my OBDII through the fender which makes it super easy to install and remove if I need to take it to the dealer.
 

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Do spend some time reading the JB4 threads as far as map settings and so forth. More importantly, take the time to record some data logs during some pulls to see if your boost settings are safe. If you don't know how to read the data logs, there are others here who can help you interpret them to make sure your AFRs are safe, the engine isn't pulling timing and there aren't any dangerous boost spikes.
 

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Discussion Starter #23
Do spend some time reading the JB4 threads as far as map settings and so forth. More importantly, take the time to record some data logs during some pulls to see if your boost settings are safe. If you don't know how to read the data logs, there are others here who can help you interpret them to make sure your AFRs are safe, the engine isn't pulling timing and there aren't any dangerous boost spikes.
Dang, just read your signature. Nice mods on yours😎👍 And, thanks for the tips. I'll be certain to learn all about logs and the different MAPs
 

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Dang, just read your signature. Nice mods on yours😎👍 And, thanks for the tips. I'll be certain to learn all about logs and the different MAPs
You know the old saying "A fool and his money are soon parted"? That's me.

The tapered boost map (#6) is the best map to use, IMHO. Running additional boost above 5,000 RPM pushes the tiny turbos off their efficiency curve and about all you'll do above 5,000 RPM is generate a lot of heat and put additional stress on the engine and turbos. Tapering the additional boost down to 0 above 5,000 RPM is a prudent thing to do and that's why I recommend using the Map 6 instead of the other maps.
 

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Looks like a Red Sport ECU calls for 11-12 psi between 5000 and 6000 RPM. SS is calling for 8-9 psi. Do you think the stock Redsport is over-boosting at stock over 5000 rpm then?
 

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Consider a spare tire kit before you start putting speakers in the trunk. You'll most likely not want run flats ever again. I didn't mnd them as others but the life on the tire was terrible and the price on new ones is even worse.
 

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Looks like a Red Sport ECU calls for 11-12 psi between 5000 and 6000 RPM. SS is calling for 8-9 psi. Do you think the stock Redsport is over-boosting at stock over 5000 rpm then?
No. I was referring to ADDITIONAL boost over stock. The RS maximum stock boost is 14.7 PSI. The SS maximum stock boost is 9.5 PSI. At maximum stock boost pressure, the RS turbos are still on their efficiency curve up to about 6,000 RPM. If you increase the boost an additional 3 PSI (~18 PSI), the turbos move off their efficiency curve at about 5,250 RPM. At 21 PSI (+6 PSI), the turbos move off the efficiency curve at about 5,000 RPM.
 

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Nice ride! I absolutely love my 19 Luxe 3.0t. I've never had such a fun car before, being mainly a truck and SUV guy. I was hesitant at first to get a small (for me) car, but I'm sure glad I did. Damn things just scorch-ass around corners, and I'm looking forward to hooking up a JB4 to it and upgrading the speakers (and adding a sub/amp). The windows need tint tho. Your pic illustrates that clearly!
 

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Very cool article! Had to look up a few things to better understand the math. - VE% is a constant for the VR30 based on cylinder capacity and displacement. The 14.7 denominator in the PR is a constant and is based on atmospheric pressure at normal altitude. That was confusing because it happens to also be the max PSI the RS puts out at stock. Not sure on the 5660 denominator in the CFM ratio or on the .069 conversion from CFM to CAF. I assume those are both just math and universal to these types of calculations and not specific to anything with our engines.
 

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In order to calculate the mass flow rate of air (CAF) from CFM, you would need to know the pressure and temperature of the air. Since the pressure ratio is taken into account in the CFM calculation, the conversion factor is dependent on the density of air. Looking at air density tables at various temperatures, the 0.069 lbs/cu.ft. air density conversion factor is based on an inlet air temperature of about 120 F.

The table in the article that was calculated from the formulas used 1.5 liters as the displacement for each turbo since there are two turbos and the total engine displacement is 3 liters. The 5660 conversion factor is to convert to cubic feet/min from liters.
 
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