[Megahurtz]

Originally Posted by ZLRob

Megahurtz, I forgot that the most important thing to see is SOI and EOI. Currently I sit in very solid standings all around with low, high fuel, SOI, and EOI under full gun with my mods. The only thing showing high on my logging is injector PW's at 6.7 ms peak which eventually comes down to 6.5- 6.6 once it settles down.

Do they hit 6.7 on the hit and then taper towards 6.5-6.6 by redline?

[ZLRob]

Originally Posted by Megahurtz

Do they hit 6.7 on the hit and then taper towards 6.5-6.6 by redline?

Precisely. That's exactly what happens since the injectors are stabilizing towards the end.

[JSH]

OP, King has/is tuned my car so I want to respond to a few of his points here. Thanks

what race gas cost per gallon(14-15.00 per gallon)"

I paid $12 today. My car is too fast now for NHRA standards because it requires a roll cage that I'm not going to put in the car. So I've taken the car about as far as I can take it with this setup and it wouldn't make sense for me to convert the car to a BBFP and ethanol car now. It's already a pretty unpleasant street car, which for me is a local interstate car.

And for the record I am far from an expert."

You're being too modest. You got more power out of my engine than did the three previous tuners.

The only reason you will make more power in cool air vs hot summer air is because you will make more boost"

Right, as ambient air gets cooler, it's air density and pressure increases which is what HPTuners sees as barometric pressure. For me in Denver I would leave here with 11.9 psia and race in Houston in January at 14.7 psia. The difference between those pressures is what I would expect to see in total increased manifold pressure. I wouldn't expect to see much increased boost otherwise.

[Megahurtz]

Originally Posted by ZLRob

Precisely. That's exactly what happens since the injectors are stabilizing towards the end.

If you're at 6.5 now, you will be past 7ms once cold weather comes. Just be careful and keep an eye on it.

I generally don't recommend anything past 6.2ms up top. 6.5 isn't going to break anything but you're hanging over the edge of spray window lol.

[ZLRob]

Originally Posted by Megahurtz

If you're at 6.5 now, you will be past 7ms once cold weather comes. Just be careful and keep an eye on it.

I generally don't recommend anything past 6.2ms up top. 6.5 isn't going to break anything but you're hanging over the edge of spray window lol.

Yeah it's right at the bleeding edge of threshold, but SOI/ EOI is 372-374/ 123-130 and HP peaks out right around 6100 RPM before it drops about 10-15 HP, but it always has with the stock blower. The power/ torque curve actually looks a lot nicer as far as level and stability is concerned than it ever did with the LT4 cam.

I have a couple fuel pressure mods I could try to implement still to reduce the tax on the injectors and lower PW but I'm not sure if it'll help much at this point because my high pressure pump starts sticking a little after 3050 psi.

[JSH]

Originally Posted by Nimair.ZL1

Anyone run a 2.40 upper with a 9.60 lower and have a ported blower? I know the combo is pretty aggressive for stock blower. Was wondering if anyone has the belt size for the particular combo as well.

9.60/2.40 at 6800 = 27,200 blower speed which is too high. Try to stay below 23,000.

[Joshinator99]

Originally Posted by ZLRob

Excellent responses you guys, thanks a bunch for taking time out of your day to respond as honestly and thoroughly as you did. Especially you King!

Josh, the only reason I run pump E is because I don't like having to take the time to math out a blend on my phone and complicate things plus I have found some extra power squeeze out of E85 over E50 blend.

Originally Posted by Megahurtz

If you're at 6.5 now, you will be past 7ms once cold weather comes. Just be careful and keep an eye on it.

I generally don't recommend anything past 6.2ms up top. 6.5 isn't going to break anything but you're hanging over the edge of spray window lol.

Originally Posted by ZLRob

Yeah it's right at the bleeding edge of threshold, but SOI/ EOI is 372-374/ 123-130 and HP peaks out right around 6100 RPM before it drops about 10-15 HP, but it always has with the stock blower. The power/ torque curve actually looks a lot nicer as far as level and stability is concerned than it ever did with the LT4 cam.

I have a couple fuel pressure mods I could try to implement still to reduce the tax on the injectors and lower PW but I'm not sure if it'll help much at this point because my high pressure pump starts sticking a little after 3050 psi.

No, you’re not getting extra power by running full E85 over E50-E60 at your power level (or even mine for that matter). E50 will let you run as much timing as your motor needs to make safe power. You are leaving a ton of power on the table by not throwing 4 gallons of 93 in with every 6 gallons of E85 (netting ~E55) as this would let you have much more fueling capacity and be able to up your blower speed.

You’re asking for trouble with your IPW numbers in my humble opinion. Just my 2 cents but I’ve played those games with DI fueling over the years and the car just won’t perform like it should when you’re on the fueling edge constantly.

[ZLRob]

Originally Posted by Joshinator99

No, you’re not getting extra power by running full E85 over E50-E60 at your power level (or even mine for that matter). E50 will let you run as much timing as your motor needs to make safe power. You are leaving a ton of power on the table by not throwing 4 gallons of 93 in with every 6 gallons of E85 (netting ~E55) as this would let you have much more fueling capacity and be able to up your blower speed.

You’re asking for trouble with your IPW numbers in my humble opinion. Just my 2 cents but I’ve played those games with DI fueling over the years and the car just won’t perform like it should when you’re on the fueling edge constantly.

I only have 91 out here and it's garbage 91 at that, so doing 93 is unfortunately not a possibility.

I know the debate between E50-60 to E85 is a never ending one, but I have found extra power out of running E50 vs running E81-82 (which is what I get at the pumps in my area). This is something that I have discussed with King and he agrees. Obviously going off the butt Dyno is not a quantifiable unit of measurement but it is worth mentioning that I immediately feel difference between the step down to E50 after running E81. My logs over time have tended to agree with that feeling as well, but the gains that are had are not in massive margins like the jump from say 91 or 93 octane to E40 or E50. This is not a good thread to start a debate nor do I want to get into one over it, but the only options that exist out here for me are:

- 91 with massively reduced timing and a super lack of power due to that lack of timing and octane availability
- 91/100 blend which only exists at one accessible station in my area and pump 100 Sunoco fuel is over $10 a gallon
- ethanol/ 91 blend to the e content of my choosing (less ideal as it requires I sit there and play games on my phone figuring out the amount of fuel to put in to reach the e content I desire) and lack of power compared to what I have observed running full pump E
- full pump E85 (E81- E82) the most ideal in my area for higher horsepower cars for cars that require over 91 octane

I know some 30 over injectors would be the solution for my build, but my son currently takes financial precedence over the car at the moment.

I've been slowly working on my fueling stuff to bring down IPW's. I'm getting there, but based on the PW's and the SOI/ EOI's, everything is still within good standings. The running conditions are super clean, no smoke on WOT runs, black soot, and solid lambda while under gun. When it gets colder out I may take another log just to see where IPW's and other related numbers stand, but given how much power this car has for the streets, I don't spend much time anywhere north of 4800 RPM unless I'm logging.

[Joshinator99]

Originally Posted by ZLRob

I only have 91 out here and it's garbage 91 at that, so doing 93 is unfortunately not a possibility.

I know the debate between E50-60 to E85 is a never ending one, but I have found extra power out of running E50 vs running E81-82 (which is what I get at the pumps in my area). This is something that I have discussed with King and he agrees. Obviously going off the butt Dyno is not a quantifiable unit of measurement but it is worth mentioning that I immediately feel difference between the step down to E50 after running E81. My logs over time have tended to agree with that feeling as well, but the gains that are had are not in massive margins like the jump from say 91 or 93 octane to E40 or E50. This is not a good thread to start a debate nor do I want to get into one over it, but the only options that exist out here for me are:

- 91 with massively reduced timing and a super lack of power due to that lack of timing and octane availability
- 91/100 blend which only exists at one accessible station in my area and pump 100 Sunoco fuel is over $10 a gallon
- ethanol/ 91 blend to the e content of my choosing (less ideal as it requires I sit there and play games on my phone figuring out the amount of fuel to put in to reach the e content I desire) and lack of power compared to what I have observed running full pump E
- full pump E85 (E81- E82) the most ideal in my area for higher horsepower cars for cars that require over 91 octane

I know some 30 over injectors would be the solution for my build, but my son currently takes financial precedence over the car at the moment.

I've been slowly working on my fueling stuff to bring down IPW's. I'm getting there, but based on the PW's and the SOI/ EOI's, everything is still within good standings. The running conditions are super clean, no smoke on WOT runs, black soot, and solid lambda while under gun. When it gets colder out I may take another log just to see where IPW's and other related numbers stand, but given how much power this car has for the streets, I don't spend much time anywhere north of 4800 RPM unless I'm logging.

Totally agree that 91 is garbage but E85 mixed with 91 to get you to even E60 will still be over 100 octane and reduce your fuel system strain by enough to get your IPWs under 6.0 ms. Just my two cents and totally understand the money it takes to fuel these cars…not cheap and life can have other priorities.

[ZLRob]

Originally Posted by Joshinator99

Totally agree that 91 is garbage but E85 mixed with 91 to get you to even E60 will still be over 100 octane and reduce your fuel system strain by enough to get your IPWs under 6.0 ms. Just my two cents and totally understand the money it takes to fuel these cars…not cheap and life can have other priorities.

Oh yeah, E60-70 is a pretty good drop down as far as reduction in PW's are concerned for mine. Maybe during the winter I can always step down the E content to 60 if the PW's show to be a touch higher than I am comfortable with seeing. I still have several mods left to implement in the fuel system as far as tuning goes so we'll see how it fares out.

[Nimair.ZL1]

Originally Posted by JSH

9.60/2.40 at 6800 = 27,200 blower speed which is too high. Try to stay below 23,000.

I talked to Brett over at Jokerz and he said I should be good as long as IAT2 stay under control. Said I should be fine unless things get hot

[Megahurtz]

E50-E60 has 90% of the power gain of E80. You can probably get another degree of timing in at E80. If you run E80 and go beyond the spray window, you start to lose power and your wideband lambda readings become unreliable.

So E50-E60 in a proper spray window vs trying to stretch the fuel system to E80 and spraying past the spray window will equal no gain or actually a loss of power up top.

Just a word of advice. 6.5ms at redline is the beginning of the area where you start to lose power up top from improper mixture and burn. When it gets cold out, you will be in the danger zone and the engine will start to detonate and/or misfire due to spraying too far into the compression stroke. This is when you start breaking piston rings.

I'm not here to tell you what to do. I'm only trying to provide some information for you to consider when you make your choices.

[ZLRob]

Originally Posted by Megahurtz

E50-E60 has 90% of the power gain of E80. You can probably get another degree of timing in at E80. If you run E80 and go beyond the spray window, you start to lose power and your wideband lambda readings become unreliable.

So E50-E60 in a proper spray window vs trying to stretch the fuel system to E80 and spraying past the spray window will equal no gain or actually a loss of power up top.

Just a word of advice. 6.5ms at redline is the beginning of the area where you start to lose power up top from improper mixture and burn. When it gets cold out, you will be in the danger zone and the engine will start to detonate and/or misfire due to spraying too far into the compression stroke. This is when you start breaking piston rings.

I'm not here to tell you what to do. I'm only trying to provide some information for you to consider when you make your choices.

I appreciate the info man! I'll keep on tuning and see if I can step it down on the fuel side.

[RobZL1]

Originally Posted by ZLRob

I appreciate the info man! I'll keep on tuning and see if I can step it down on the fuel side.

What lambda are you running? Any room to lean it out more? I think that's all you can play with in the tune based on what you already noted.

Sounds like here's the breakdown:
- SOI in the 370's
- EOI in the 120's
- Pulse width over 6ms
- Rail pressure tapped out at 3000 or so

With those conditions, I think the only thing left you can do in the tune is lean out the mixture, right? (or reduce the E content as noted) I don't see where you have any other options within the calibration.

Side note- I think it's great that we have guys like Jason and Joe on here that contribute on a regular basis, with lots of first-hand experience on these platforms. Really helpful for guys like me who tune a small handful of cars for myself and close friends as a hobby, who don't have the week-in, week-out experience these guys do.

So thanks to both of you (and a couple others). I'm glad you guys are here and willing to contribute.