They are all going to hit the same limit on pump gas really, again the issue is not the turbo's being able to make the power it is the octane of the fuel allowing the power. It was pushing it on 93oct and 380whp. I could of made more, but safely I like to stick to 370-380whp. Once you get some good fuel in there the next problem you run into is the stock fuel system running out. I have been able to make 440whp/440wtq on my vehicle with the stock fuel system and 100oct. On Pump gas I would cut it out at 380-385.
This thread is focused on spool not overall power numbers as spool is the most asked question from customers when they are in the market for a turbo kit/upgraded turbo.
Yeah i saw but thats when i confuse things, some of those charts on other turbos dont dive like that, im assuming all of these are on stock heads, so is it back preasure like vvt said?
How can it be the head or cams, when all the motors are stock. It's not the head or the cams causing the 7163 to fall off up top. It's the mixed flow turbine wheel, and tight twin scroll housing. This is turbocharging 101. If it was the head, and the cams you would see every turbo no matter what it's size falling off up top. Is the head restrictive, yes, are the cams begging to be replaced, also yes, but neither of those are the reason the 7163 falls off up top. Turbos are always a trade off, look at the way the 7163 spools, that tells you all you need to know, tight turbine twin scroll housing, and less mass for the exhaust energy to spin. You want to stock like spool, and a tapering power curve up top, run a smaller turbo. You want less tq down low, but a car that pulls hard to redline go with a bigger turbo, or one with a larger AR turbine housing. The 7163 is honestly the best spooling option, but it's basically out of breath up top on this motor at those levels. Of course we are biased, but stage 2 is the best compromise of spool, and top end power, at 1/3-1/2 the price of the competition. Pretty hard to beat
When the amount of air coming in exceeds what the engine can process you get backpressure in the charge system which will slow the turbo down and decrease boost. The same turbo I have on my car on a Subaru holds 35psi to redline no problem and there is no torque dropoff. On my car boost starts to drop and that is when the torque curve plummets.
Only one being held back is the Full-Race kit on my car. I have the boost coming on a little less than what it is capable of but only because I was afraid of traction issues not LSPI. Which, traction was an issue when I went to Florida for the NMRA event. I had 6% slip in 3rd gear and it stemmed from first having too much torque and short gear. I need a taller tire as well and some more suspension.
If the turbo is too smaller it will be effected more. The 5858 moves more air than the 7163 when at full spool. When boost drops torque is going to drop, that is turbocharged engines 101.
Thank you for sharing!
Agreed, dynojet unloaded is what I'm using for comparison to keep things as even as possible. There are ALWAYS going to be variances.
Exactly, this turbo kicks ass, as far as spool, runs out of breath pretty quick, but its a spool monster. Awesome graph!
Good post, I didnt know you guys did a kit for the EFR 7163, a lot of guys on here want those big #s and you did this kit over a year ago, pretty cool, and your local to me.
