First Goal: 550hp LS1 Getting 30mpg

[bazman]

Originally Posted by mikesanto70

how tall are we talking like 2:56 and you say more accurate injectors, could you please be morespecific because we all would like better mpg's from our LS motors!!

Both my 4100lb sedan (with me in it) and the Viper have the same 3.07 final drive. However my 4th gear is 07:1 giving an effective final ratio of 2.149:1. The Viper however has a 0.5:1 rato in 6th gear giving a final drive in 6th of 1.535:1. In other words it is idling along at 60mph.

A Viper from the factory in good tune can easily get 25-28mpg if driven very carefully on the highway/interstate. To get the extra 2mpg simply requires a tune that injects less fuel per cycle yet maintains power to maintain cruise speed. In the case of the 1000hp turbo Viper that improvement was a simple combination enabled by custom tuning and after market low impedance injectors that tolerated a more accurate map than stock injectors could. Sorry I don't know the injector make. The custom tune would have been leaner at cruise with as much spark advance as was useful. Factory tunes are conservative and never run as lean or as much spark advance as the engine might like.

My LS3 runs the latest state of art Bosch EV14 injectors and they are worth a little mpg over stock OEM older style injectors. Their main value however is they are available in far higher flow rates so can support more power. LS engines are easy to get great power and economy out of. Mine has 300hp at the wheels as low as 2600rpm, which is phenomenal torque for a 6.2.

[UltArc]

Originally Posted by bazman

Both my 4100lb sedan (with me in it) and the Viper have the same 3.07 final drive. However my 4th gear is 07:1 giving an effective final ratio of 2.149:1. The Viper however has a 0.5:1 rato in 6th gear giving a final drive in 6th of 1.535:1. In other words it is idling along at 60mph.

A Viper from the factory in good tune can easily get 25-28mpg if driven very carefully on the highway/interstate. To get the extra 2mpg simply requires a tune that injects less fuel per cycle yet maintains power to maintain cruise speed. In the case of the 1000hp turbo Viper that improvement was a simple combination enabled by custom tuning and after market low impedance injectors that tolerated a more accurate map than stock injectors could. Sorry I don't know the injector make. The custom tune would have been leaner at cruise with as much spark advance as was useful. Factory tunes are conservative and never run as lean or as much spark advance as the engine might like.

My LS3 runs the latest state of art Bosch EV14 injectors and they are worth a little mpg over stock OEM older style injectors. Their main value however is they are available in far higher flow rates so can support more power. LS engines are easy to get great power and economy out of. Mine has 300hp at the wheels as low as 2600rpm, which is phenomenal torque for a 6.2.

Originally Posted by bazman

Well, I got 31.24mpg from the 550hp LS1 on a trip under perfect conditions but no hyper milling. Averaged 100kph (62mph).

Sadly that is imperial mpg, so that translates to 26mpg US or 9.09L/100km. Still not as good as the stock cam but I am yet to install the new state of art Bosch EV14 injectors which should gain another 3-4% over the bored out crappy injectors I am now using as there are several areas where the tune can be improved with better injectors.

We are getting there :-)

It's not bad for a 4000lb 4 door sedan with auto. Figures are no BS dash reading, these are actual kms and actual fuel used topping up by sight to ensure same level at each fill up.

606 foot pounds of torque is pretty crazy. Is it normal for the engine to only rev to 4.7k? I know a lot of v8s will only go into mid 5s, but I thought the LS series was usually good to 6k or so.

[bazman]

Originally Posted by UltArc

606 foot pounds of torque is pretty crazy. Is it normal for the engine to only rev to 4.7k? I know a lot of v8s will only go into mid 5s, but I thought the LS series was usually good to 6k or so.

It is crazy, especially when 606rwtq means around 750ft/lb at the crank on an auto! 4700rpm sounds very low for an LS, is that all yours pulls? My LS3 goes to 6500 and pulls all the way, so when I say 300rwhp at 2600rpm the power climbs from there not peaks I peak at 5500 but only because the turbo is too small, it still makes good power to 6500. I'll pick up 150rwhp by changing the turbo, but for now the tires can't cope with what it has got

[mikesanto70]

Originally Posted by bazman

It is crazy, especially when 606rwtq means around 750ft/lb at the crank on an auto! 4700rpm sounds very low for an LS, is that all yours pulls? My LS3 goes to 6500 and pulls all the way, so when I say 300rwhp at 2600rpm the power climbs from there not peaks I peak at 5500 but only because the turbo is too small, it still makes good power to 6500. I'll pick up 150rwhp by changing the turbo, but for now the tires can't cope with what it has got

TURBO BABY!!!! :-)

[UltArc]

Originally Posted by bazman

It is crazy, especially when 606rwtq means around 750ft/lb at the crank on an auto! 4700rpm sounds very low for an LS, is that all yours pulls? My LS3 goes to 6500 and pulls all the way, so when I say 300rwhp at 2600rpm the power climbs from there not peaks I peak at 5500 but only because the turbo is too small, it still makes good power to 6500. I'll pick up 150rwhp by changing the turbo, but for now the tires can't cope with what it has got

I don't have an LS or any 8s, no need for the power of a modern one and no care for the fuel consumption of an older one.

I thought YOURS had 606 torques on the rear wheels, 300 hp at 2600 rpms worked out to that when I did the math- could be wrong.

[bazman]

Originally Posted by UltArc

I don't have an LS or any 8s, no need for the power of a modern one and no care for the fuel consumption of an older one.

I thought YOURS had 606 torques on the rear wheels, 300 hp at 2600 rpms worked out to that when I did the math- could be wrong.

You got it right I was just saying that those are not peak numbers just what it does down low and that 606 torque at wheels = around 750 at the flywheel

BTW - impressive economy you have got, re the 3.7 Mustang - other than hypermilling any special mods/tuning?

[UltArc]

Scanguage II-2012/06/18; 18" OEM 2013 Mustang GT wheels with Pirelli P Zero tires-2012/07/03; Axle Back Exhuast, Front Fascia, Front Air Splitter, Side Splitters, Grille Block-2012/07/18; Cold Air Induction, GT/CS Rear Valance-2012/10/05; Air dam & Upper Grille Block-2012/10/18; Antenna Delete-2013/01/06; UltraGuage Install-2013/02/23; Kill Switch Install-2013/03/17; Premium Fuel Only-2013/04/13; Lower grille block-2013/05/11; Swapping Single Piece Air Dam for New Two Piece-2013/06/01; Full Underbody-2013/06/05; - Details: 2012 Mustang 3.7/M - 2012 Ford Mustang 3.7 Fuel Economy - EcoModder.com

If you're making 300 hp @ 2600, and you're redlining at 6500, your engine should be at 750 ish by math, but not sure how if it works the same with turbos.

[mikesanto70]

If you're making 300 hp @ 2600, and you're redlining at 6500, your engine should be at 750 ish by math, but not sure how if it works the same with turbos.[/QUOTE]

how did you get 49.44 from a 3.7 Mustang? what terrain was it over and how many miles were driven to make that average? You would be surprised what a flat highway can do for mileage, I drove from Phoenix to LA in my stock 98' Crown Vic 4.6L V8, from Phoenix to Blythe I averaged 30 mpg in the Summer w/ A/C on and 80 mph ... from Blyth to LA it dropped to 24.5 mpg.... because of the hills and some brief stop and go close to LA...404 mi door to door

[UltArc]

Originally Posted by mikesanto70

If you're making 300 hp @ 2600, and you're redlining at 6500, your engine should be at 750 ish by math, but not sure how if it works the same with turbos.

how did you get 49.44 from a 3.7 Mustang? what terrain was it over and how many miles were driven to make that average? You would be surprised what a flat highway can do for mileage, I drove from Phoenix to LA in my stock 98' Crown Vic 4.6L V8, from Phoenix to Blythe I averaged 30 mpg in the Summer w/ A/C on and 80 mph ... from Blyth to LA it dropped to 24.5 mpg.... because of the hills and some brief stop and go close to LA...404 mi door to door[/QUOTE]

My 49.42 mpg record was racing at the Green Grand Prix on the Glen Watkins International Raceway. Before that it was 47 and change over 440 miles from Ohio to North Carolina.

I don't want to derail a different thread, you're welcome to visit my build thread for my Mustang