Hetzle

Hey all,

As awesome as the car is with a Renntech tune, I would love to unlock power at the top of the rev band, restoring that amazing feeling of power progressing all the way to redline, while of course getting a nice power bump as well. I do not plan on installing DP's or any crazy fueling setups (no meth or E85) and want to continue running 91 octane. I understand that won't net me any crazy numbers, I don't need too much of a monster and am really just aiming for the 600's at the wheels.

With that said, a friend of mine was recommending going with the Pure 1000's anyway, claiming they would be more efficient at heat management. Is there any truth to that? Are there any other advantages over going with the 1000's? How about disadvantages?

Thanks!

Bijan Kohan

u

Hows it going? I’ve had some good experience running pure stage 2 on my ‘16 GTS, I’m running a tune along with catless DP’s as well.

So I have had this setup for a couple of years now. With 91 octane (I’m located in West LA) the highest I’ve achieved is 590 WHP which was very disappointing as I thought I’d be hitting 650 easily. Just recently I took my car to a local tuner and with a 94 tune and 94 blend fuel I hit 675 to the wheels which I thought was impressive considering no meth or e85.

I have already ordered high pressure fuel pumps and having them installed enabling me to use e85 on a nice e85 tune. I’m expecting 700 WHP with this setup.

Bottom line, the pure turbo upgrade will definitely not give you more power and is completely not worth it if you are not considering running 100% or fuel upgrades. If you’ll be happy with 550-600 whp then go for it but those are very low numbers for doing a turbo upgrade. All these crazy numbers you see with pure setups are cars running at least 93/94 octane + 100% meth or 100 octane race fuel to achieve 700-800+ numbers.

Just my .02.

Hetzle

Hey man,

Thanks for elaborating on your experiences I am amazed that 3 octane netted you another 85whp. I had an e85 setup with additional fueling on my last car, and while it was crazy fun, I no longer want to deal with the hassle of filling up at specific stations. Plus, I think I would be happy with ~590whp - as mentioned I am not aiming for crazy numbers, really just looking for a power bump and to restore power building progressively to redline. Any faster feels like it would be edging on too much for my tastes.

502Bill

If your goal is to move your power curve to the right, bigger turbos will do that. However, given your fuel limitations you will not build turbo efficiency, mostly lag. Downpipes and a tune will net you closer to your power goal with stock turbos. Best of all, its reversible. Not sure you would be happy with Pure 900/1000 on 91 octane.

kumizi

I was also advised by Eurocharged to not even consider the smaller turbos and go with the bigger ones if top end power was the goal. I made right at 700whp with catless downpipes as the only other mod. 93 octane, stock fuel pump and injectors

kumizi

so happy to hear you got it sorted out

with e85 and enough fuel pump, you should be able to make 800whp. it's just a matter of how much you want to push/risk the transmission.

here's a c63s running 28psi

Hetzle

Thanks for your input Are you running the 900's or the 1000's?

Thanks Your point about lag is interesting, I will see what EC says.

For context, my last car was a Pure Stage 2 335i on e85 and did 515/531 at the wheels with progressively climbing torque that peaked and flattened out at around 4.4k and I LOVED the way that felt, however it had downpipes and the smell is not something I can live with unless I run e85 all the time, which I'm over doing. The Renntech tune definitely woke the car up and made it feel faster, but it seriously falls flat on its face in the higher revs and I find the way power builds to be unsatisfying. Renntech claims the car should be around 529/512 on 93 octane so, according to my back-of-the-napkin math 91 fuel probably brings it closer to 500/490 at the wheels.

Eurocharged mentioned I would get around 672hp / 700tq crank with the 900's (591 / 616 at the wheels) and that the 1000's would exchange some mid range for higher end power and also a bit higher peak numbers (I'd guess around 700 crank). So, + 90whp / 126wtq is a significant bump and would make the power curve more satisfying.

Check out the torque curves below:

Renntech Stg 1 - peak torque is between 3-3.5k and then drops off hard, dipping down a total of 27.7% by redline (512 - 370 = 142. 142/512 = 27.7%)


Pure 900's - torque climbs progressively and peaks around 5.1k with a 17.6% drop to redline (680 - 560 = 120. 120/680 = 17.6%)


Pure 1000's - torque climbs progressively and peaks between 5.2-5.5k and drops 15.7% by redline (750 - 632 = 118. 118/750 = 15.7%)

kumizi

I had the bigger ones (that’s what she said). They keep changing the names of the turbos.

The car felt like it should. It would pull all the way to redline instead of running out of steam at 5000.

502Bill

Eurocharged does great work. If they say you can pick up that much power on 91 then I believe it. I put down 732 on 93, meth/water and downpipes with a pair of 900s. Pulls all the way to redline.

Bijan Kohan

Yes I believe I’m on the way to my goal. Those are some impressive numbers on the c63s but then 28psi is pretty high. Is this car running the HPFP’s like I’m getting installed? Are those dyno numbers on E85?

I received my HPFP’s from XDI after preordering them and waiting a good 3 months. Now my car is at World Motorsport in Torrance waiting in line to have the work done.

My concerns are:

1) Is E85 safe for our motors, long term? Since our cars are not technically “flex fuel” cars.

2) I have a United Oils gas station a few minutes from my home who offers E85 by Pearson Fuels and at the pump it shows that the ethanol content could range anywhere from e51-e85. I am getting a gauge installed that shows ethanol content every time I fuel up. I’m hoping that it will be a good quality consistent e85. I’m planning on having a less aggressive e60 tune on my handheld as well in case the e85 is not a true e85.

3) I am looking to achieve high HP and keep my torque very limited. I would be happy with my HP in the high 7’s and torque in the low 6’s or even high 5’s. Similar to the S2k (owned 2 of them) 240hp and around 160 torque. And the e92 m3, around 420 hp and 290 torque. IMO this ratio feels SO much better to drive and the low torque would definitely be a lot easier on the motor/trans/chassis etc. I’m hoping my tuner can achieve this.

let me know your thoughts.

Hetzle

Very interested in. learning the answers to Bijan's concerns above! Wanted to add a summary of my conversations with Eurocharged:

Assuming 91 octane (no meth or additional fueling) and stock DP's:

900's
~600whp (@ 12% drivetrain loss)
Power curve is close to stock
Relatively more mid range
Relatively less top end

1000's
~640whp
Relatively less mid range, enough to make the car not feel "peppy" around town
Relatively more top end
Need to go with additional cooling + higher octane fuel or meth to make them worth it