question for anyone with flex tune

Viper1500

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Any of you all that have a flex tune and are making 16+ lbs of boost, I am curious if you have done a before and after an intake change? No matter what brand. Did you have to retune for it?
Was there a good power difference? Did the IAT change? My truck runs excellent now with the flex tune and I am on E85 all the time now. But I'm all for more power if it comes from efficiency
I love the design of the S&B but just not sure its worth it.
 
Any of you all that have a flex tune and are making 16+ lbs of boost, I am curious if you have done a before and after an intake change? No matter what brand. Did you have to retune for it?
Was there a good power difference? Did the IAT change? My truck runs excellent now with the flex tune and I am on E85 all the time now. But I'm all for more power if it comes from efficiency
I love the design of the S&B but just not sure its worth it.
I believe @10mpg did dyno with and without S&B and showed 20awhp gain while he was already making significantly more power.
 
I believe @10mpg did dyno with and without S&B and showed 20awhp gain while he was already making significantly more power.
It would make sense that it should at least make as much difference on a modded set up if not more as more air is required.

Thanks for the reply.
 
It would make sense that it should at least make as much difference on a modded set up if not more as more air is required.

Thanks for the reply.
It made 20whp when I was already over 900whp to begin with. A lot of people assumed it would make more at higher power but that was not the case. Stock TRX and heavily modded both made about the same.
 
It made 20whp when I was already over 900whp to begin with. A lot of people assumed it would make more at higher power but that was not the case. Stock TRX and heavily modded both made about the same.
You ever do a pull with the lid off? My hypothesis is that the ducting (from front rad area and hood) in the intake is the limiting factor in stock form, and also for the aftermarket intakes. While the aftermarket ones improve the flow, it’s not enough to stop that from being a choke point.
 
You ever do a pull with the lid off? My hypothesis is that the ducting (from front rad area and hood) in the intake is the limiting factor in stock form, and also for the aftermarket intakes. While the aftermarket ones improve the flow, it’s not enough to stop that from being a choke point.
I did a couple pulls with the exposed filter with no shroud at all. It did not seem to change much from what we could tell. 20whp really isnt that impressive from the fact that we also kept the stock intake and all we did was remove the filter and it picked up 10whp just from that, showing how restrictive the OEM filter is (for good reason, as it was meant to filter out sand and crap)
 
I did a couple pulls with the exposed filter with no shroud at all. It did not seem to change much from what we could tell. 20whp really isnt that impressive from the fact that we also kept the stock intake and all we did was remove the filter and it picked up 10whp just from that, showing how restrictive the OEM filter is (for good reason, as it was meant to filter out sand and crap)
Interesting. Hypothesis proved false then perhaps. Appreciate you sharing the information.
 
Interesting. Hypothesis proved false then perhaps. Appreciate you sharing the information.
Yeah. It is what it is. At the end of the day the price for a 20whp pick up is not bad once you get way down the list of mods. After you've done the basic pulley / tune / E85 route shit the dollar per horsepower cost starts to go up exponentially but of course you know all of this :)
 
I don’t, and have loved the recent threads on tuning/e85/performance mods. Much appreciated to all those who have MUCH more knowledge about this stuff then I and are willing to share. 👊🏼
 
I did a couple pulls with the exposed filter with no shroud at all. It did not seem to change much from what we could tell. 20whp really isnt that impressive from the fact that we also kept the stock intake and all we did was remove the filter and it picked up 10whp just from that, showing how restrictive the OEM filter is (for good reason, as it was meant to filter out sand and crap)
Thank you for sharing. By any chance did you have to change the tune after changing the intake?
 
Thank you for sharing. By any chance did you have to change the tune after changing the intake?
No, not necessary for intake only. We changed nothing in between those dyno runs except the intake itself.
 
Who can I get the flex tune from? I didn’t think it would work in a close to stock truck as the injectors seem to be the first problem we run into?
 
Call curt Dusterhoff and tell him steve from Washington state sent you. Personal friend of mine and a awesome tuner.
 
Can you get an ethanol sensor input into the ECU to run a true flex fuel tune and not just an E85 map?
 
Can you get an ethanol sensor input into the ECU to run a true flex fuel tune and not just an E85 map?
Curt runs inferred flex tune. No sensor needed. Uses the stock wideband gauge to calculate. Same as most stock flex fuel vehicles run. Either Barth or Satera add the sensor and use that (similar to what the GM guys do). All 3 of those shops run true flex fuel (not dual tune).
 
Curt runs inferred flex tune. No sensor needed. Uses the stock wideband gauge to calculate. Same as most stock flex fuel vehicles run. Either Barth or Satera add the sensor and use that (similar to what the GM guys do). All 3 of those shops run true flex fuel (not dual tune).
Gotcha, thanks for the clarification! In the GT-R world, we hijack the secondary air input for a GM FF sensor input and run a blended map. Didn't know if there was something on the hellcat that could be re-purposed. True FF is the only way to do E85 as far as I'm concerned.
 
Gotcha, thanks for the clarification! In the GT-R world, we hijack the secondary air input for a GM FF sensor input and run a blended map. Didn't know if there was something on the hellcat that could be re-purposed. True FF is the only way to do E85 as far as I'm concerned.
No problem. Yea I used the FF sensor added on for my V so familiar with the setup. On the hellcat platform there is a stock wideband sensor. HPTuners has a pretty recently added feature within it to run flex fuel using the wideband to calculate ethanol content based on AFR and fuel trims. As far as I know only 3 tuners out there familiar enough with that tuning method though including Curt.
 
No problem. Yea I used the FF sensor added on for my V so familiar with the setup. On the hellcat platform there is a stock wideband sensor. HPTuners has a pretty recently added feature within it to run flex fuel using the wideband to calculate ethanol content based on AFR and fuel trims. As far as I know only 3 tuners out there familiar enough with that tuning method though including Curt.
I'm going to have to do some reading up on how to use a wideband for FF management. Learn something new everyday!
 
Curt has tuned 100's of hellcats and his flex tune is dialed and works perfectly. I have a flex set up on my 2021 hellcat superstock also but on that car If I want to run e85 I just drain the tank, fill her up with e85 and flash my race e85 tune in it. I run the car hard so If I'm going to fuck around with e85 I'd rather just run my big race tune and my 20lb boost tune. What I like about the flex in my trx is I can be coming back from Eastern Washington and there's a gas station on the way back right off the highway that sells e85 so I can put in 15 gallons of e85 and pick up 50 or more hp just with the fuel and the added timing when the wideband sensor picks up on the new fuel. It's just a bad ass set up. There's only 2 stations in Washington that I know of that sells e85 so I keep 4 drums in my shop and when I drive by the station I fill up some cans and keep my drums filled up at home. In the spring I take a day and make 2 trips to get 200 gallons of e85 and that will last a long time running it in my hellcat. I don't run e85 in my trx to often but the power difference on the truck is insane.
 
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