Subaru WRX Forum banner
1 - 13 of 13 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 ·
Hey all,

I just installed cobb flex fuel and wanted to post my graphs and see how they compared to people with similar setups.

Event: Dyno Pull
Location: JM Automotive, Minneapolis Minnesota


2013 Subaru WRX
Tuner: Devin from JM auto
Dyno Info: Dynotech
Transmission: 5spd
Gear: 3rd
Peak HP : E85- 367.9 hp 91- 304.5 hp
Peak Torque : E85- 435.5 tq 91- 357.0 tq
Target Boost: 20PSI

Cobb catted DP, Cobb AP, Grimmspeed TMIC, Cobb flex fuel, ID1050s, AEM320 fuel pump, AEM Intake, TGV Deletes, Nameless exhaust, Comp clutch stage 2.

This is with an Ethanol content around E70.
Text Line Plot Font Design

91 Octane Tune
Text Line Font Plot Design
 

·
Super Moderator
Joined
·
11,429 Posts
That’s a fierce amount of power. Stock block?
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #5 ·
Well I am hoping it least last a little while, I just had the block rebuilt.

JMA Stage 1 – 500 HP Rating

Rebuilding a used block. We tear it all the way down to just the case halves. Send the case halves out to be torque plate bored and honed. Rebuild the heads back to OEM spec and assemble using OEM gaskets and seals. This option comes with Manley forged pistons (or JE Pistons for hybrid builds). With this option we also use good, OEM spec, STI rods and a polished OEM STI spec crankshaft. Lastly, we get rid of the horrible factory bearings and clearances and install King Racing bearings
 

·
Registered
Joined
·
171 Posts
Hmmm. You're pushing it with STI stock rods. But at least it's something

You're stressing the hell out of the turbo with those numbers
 

·
Premium Member
Joined
·
112 Posts
Thanks for sharing. Looking to do this soon. Please follow up if you run into any issues, and if you've got any maintenance regimen for removing water from the tank, or any observations you have about reliability impacts.
 

·
Æternum
Joined
·
15,860 Posts
Hmmm. You're pushing it with STI stock rods. But at least it's something

You're stressing the hell out of the turbo with those numbers
The turbo is seeing no additional stress from any other situation. At 20 PSI, the turbo is very likely well within its efficiency range. The higher effective octane of the Ethanol and more optimal timing should further reduce the EGT, so if anything the turbo is seeing less stress.

I also disagree with the rods. EJ25 rods are fairly beefy and 430wtq on most dynos should still be within the "comfort" range. The FA20F, with thinner rods and a poor R:S ratio is far higher risk of ejecting rods. I'd be far more concerned about the transmission.

That dyno plot does a fantastic job of illustrating just how knock-limited these motors really are on pump fuel, and just how "small" for the cubes the VF39/48/52 really is.
 

·
Æternum
Joined
·
15,860 Posts
Well like most people, once you start getting more power you just want more :) I ended up getting a Blouch 20GXT-R 8cm2 Turbo and installed a Grimmspeed uppipe with a turbosmart EWG, and an IAG AOS.
View attachment 312750
Interesting.

I wonder if the torque drop-off on the plot is due to the turbo's efficiency or if we are legitimately seeing the maximum practical VE that can be achieved with OEM heads and cams.

What does the boost taper to by redline?
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #11 · (Edited)
I wanted to update this post because I have now installed Killer B header, Perrin turbo inlet, and a nameless midpipe and now making more power! It's crazy how much the header increased the power over the entire powerband.
 

Attachments

·
Super Moderator
Joined
·
11,429 Posts
That transmission hates your soul. Beastly numbers for a stock turbo though
 
1 - 13 of 13 Posts
Top