Hey all. Was just wondering if 24psi from my stock K04 is going to have the same power and torque as a ZFR at 24 psi. I know the ZFR is a bigger turbo and if I wanted a power increase in the future it could be on tap with a re-tune. But is it worth it with a 91 octane tune and trying to maintain engine life?

 

Not even close to the same power levels. Your talking about the max safe zone for the K04 and a low psi tune for the ZFR... It's really only a measurement of restriction in that you could make the same/more power on 20 psi with the ZFR than you could at 24 on a K04... Get it?

 

Zfr flows more air so no, zfr will make more power at 24 psi than k04

So k04 at 24 psi would flow 24 pounds per square inch of air at 32 lbs a minute and zfr would flow 24 psi at 54 lbs a minute. So both turbos compress the air the same, but zfr pushes that 24 psi into motor faster so u got more air in cylinder at 24 psi on zfr then u would on a k04 at the same psi

 

If I have those numbers right that is

 

just remember PSI means absolutely nothing!!

 

See that's not true. Psi does mean something. If u had 54 lbs/ minute going into the motor at 1 psi ud make less power than at 24 psi. U compress the air charge more it holds more oxygen than when u compress it less. So obviously it means something. I think the better thing to say is psi or airflow by themselves mean nothing, u have to look at both really.

 

Excellent. Thank you gentlemen. My K04 at 24 psi is very motor safe. Can the same be said of the ZFR?

 

Zfr at 24 psi will be motor safe, but not trannysafe, due to it makes a lot more torque very quickly at low rpm, almost like pretty much as fast as with stock turbo , so all that power coming on with stock tranny and 3rd gear go boom. Gotta tune so torque doesn't come on so quick or even better, get a Powell 4.45 gear tranny upgrade like gonna have to lol

 

If mine blows I'm getting a 6 speed. I have enough money in the car to justify it. Plus I'm keeping it for a long time so why not.

 

zfr flows better so for ricer math purposes lets just say where a 24psi k04 makes ~315whp, and zfr at 24psi might make ~380whp.

 

No the powers is different. Compressor maps and efficiency ranges for the two different turbos vary greatly, and so will performance.

 

Lol at op's question, but that's what is so great about the zfr. Even at the same psi levels you're going to have more power and a broader powerband till redline that won't die off around 5-6k like the k04.

Pretty much what everyone else said

 

I don't know if this is strictly true but I have noticed it in most cases.

Pressure seems to increase torque more then hp
And flow seems to increase hp more then torque

 

Obviously there are many factors but Just to simplify it...

 

Would the increased efficiency of the zfr create less heat of the compressed air, compared to the heat created at the limits of the k04?

 

My head sort of hurts after reading those responses.

PSI is basically a measure of the head loss in your piping system. The head loss is a function of the density of the air and the restrictions in your system. Two turbos boosting 24 psi just means that the head loss between the two is the same. The flow rates are different because one turbo might be more effient than the other in that range, meaning the charged air is less hot (more dense).

 

u are really close

I did 31 lbs/min and dyno 318whp. our hhr zfr did 39 lbs/min and 390 whp

 

so I guess to summon up what everyone said, yes 24 psi is 24 psi, how much air the turbo flows is what makes the difference. end thread. lol

 

Put both on high and check for results

 

nice lol