Topic: Fuel consumption

What type of fuel consumption do you get during a race?  (What are you driving?)

Was happily surprised by ours last weekend.  3.7gph

BMW e30 m20b27 ETA motor

"We Got Screwed" NHMS 2017, 4th NHMS 2020,  4th NJMP 2021,
"Judges Choice" NHMS 2021,10th NJMP 2022, 3rd Thompson 2022
#847 Batmobile  aka-"Beulah"  search Squidrope Racing on Facebook

Re: Fuel consumption

v8 infiniti 9.6gph

Homestead Chump 5th-Sebring 6th-PBIR Lemons 9th - Charlotte Chump  CrashnBurn 9th
Sebring 6th again -NOLA Chump 1st -PBIR Chump Trans Fail 16th
Daytona 11th - Sebring 6th - Atlanta Motor Speedway 2nd - Road Atlanta Trans Fail 61st-Road Atlanta 5th
Daytona 13th - Charlotte 9th - Sebring 2nd-Charlotte 25th broken brakes - Road Atlanta 14 10th-Daytona 14  58th- Humid TT 19th Judges' Choice!

Re: Fuel consumption

Prelude, 2000 lbs, give or take driver size
5 gallons per hour, but that is on a nice day
Not wet, rainy, drizzly, wet Thompson track....that is probably closer to half....like 3 gallons per hour...
My estimate, since we have no fuel gauge (nor speedometer)....I should get one, but it is not high on my list...

MarioKart Driving School: 1987 Honda Prelude Si (Opus #28) 
Loudon, NH 2014 - Millville, NJ, Lightening 2019 (RIP)
New and improved: 1987 Honda Prelude Si (Opus #11) Pittsburgh, PA 2021 - ??
and finally won something, Class C Win: Loudon, NH 2022

Re: Fuel consumption

Saturn SC2 4.5 GPH.  Dustbuster minivan with manual conversion 5.5-6 GPH.  1947 Plymouth with original engine 2.8 GPH.

Only one of the data points is useful to anyone but us.

Re: Fuel consumption

Depends on conditions, but averages about 6.5 gph  e36 325 bone stock m50b25  with stock sized tires as they make a difference.

Re: Fuel consumption

We had a bone stock miata that probably lost plenty of horsepower since 1992. 12 gallon tank, we probably filled up like 3 or 4 times at Kershaw. Don't remember how many laps we completed but we came in like 75th out of 140 overall haha.

7 (edited by TheEngineer 2018-08-21 10:13 AM)

Re: Fuel consumption

This thread may be relevant to your interests. (yes it's older, but it has 3 pages of responses that may help)

https://forums.24hoursoflemons.com/view … p?id=16336

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

8 (edited by mechimike 2018-08-21 10:32 AM)

Re: Fuel consumption

Oh look, another "What's your fuel consumption" thread!

1975 LTD with a 460 big block and 3.50 gears.  You don't want to know.

Tunachuckers: 15 Years of Effluency
'08 - '10: 1966 Volvo 122, "Charlie"
'10 - '18: 1975 Ford LTD Landau --> 2018 - current: Converted into 1950 "Plymford"
'22 - current: 1967 Volvo 122, "Charlie ]["

9 (edited by n0m4d 2018-08-28 06:32 PM)

Re: Fuel consumption

Our e12 w/ m30 is 7 gph.  Our previous e30 w/ a m42 was a glorious 2.5 gph (easily could do 3hrs on a stock tank of gas).

30 entries since 2009
#39 & #53 Overengineer'd Racing - Wilton, NH
http://www.facebook.com/nhlemons

Re: Fuel consumption

Depends on the carb.  We did 10 GPH at road atlanta with a re jetted holley

Put on a pro form 650, and its now 7

88 t bird with a high mileage 5.0.

Silent But Deadly Racing-  Ricky Bobby's Laughing Clown Malt Liquor Thunderbird , Datsun 510, 87 Mustang (The Race Team Formerly Known as Prince), 72 Pinto Squire waggy, Parnelli Jones 67 Galaxie, Turbo Coupe Surf wagon.(The Surfin Bird), Squatting Dogs In Tracksuits,  Space Pants!  Roy Fuckin Kent and The tribute to a tribute to a tribute THUNDERBIRD/ SUNDAHBADOH!

Re: Fuel consumption

4.5 gph. 1950lb Mazda MX3 with 1.8L V6....yes, V6.

Re: Fuel consumption

5 gph 2.0L Honda B20

Captain
Team Super Westerfield Bros.
'93 Acura Integra - No VTEC Yo!

Re: Fuel consumption

I have a theory that all that the largest factor is HP (assuming reasonable efficiency IE no carbs) so I would find it interesting to estimate HP. My 210ish hp 325 e46 does 5gal per hr
My 210ish hp Thunderbird does 5 gal per hr. My boss's real race car e36 with 260hp s54 somehow does 10gal every 50 mins.

Owner/Captain of The 27 Club E46. Phoenix, AZ
and now the #95 Thunderbird

Re: Fuel consumption

It’s somewhat a function of HP, but it is also how quick the car is being driven.   The same car with a faster driver consumes more fuel. 

Also amazed at your 325i’s fuel efficiency. 

LemonAid - Changing kids lives one lap at a time.

15 (edited by OnkelUdo 2018-11-03 10:29 AM)

Re: Fuel consumption

Sexy jesus wrote:

I have a theory that all that the largest factor is HP (assuming reasonable efficiency IE no carbs) so I would find it interesting to estimate HP. My 210ish hp 325 e46 does 5gal per hr
My 210ish hp Thunderbird does 5 gal per hr. My boss's real race car e36 with 260hp s54 somehow does 10gal every 50 mins.

This would be all good in theory (same track and similar pace assumed) if not for significant differences in:

How fast does it get to that 210'ish?
What is the gearing/transmission like?
Weight.
Cornering speed.
Type and quantity of forced induction.

Great example...our minivan with the original automatic tranny and Buick 3800 NA almost always bounced between 6 and 7.5 gph depending of driver.  Slap a manual in it with significantly different gearing and and the massively more effecient power transfer it dropped to an average just under 6 GPH at the same tracks with our most aggressive driver and 5.5 gph for most drivers.  Nothing changed on the engine.  4.5 races with the manual and probably about 8 with the manual so big enough sample size to be statistically accurate.

16 (edited by squidrope 2018-11-03 05:06 PM)

Re: Fuel consumption

TeamLemon-aid wrote:

It’s somewhat a function of HP, but it is also how quick the car is being driven.   The same car with a faster driver consumes more fuel. 

Also amazed at your 325i’s fuel efficiency.

Not an "i"  It's an ETA

Thompson was wet and mileage was different than what we experienced at NHMS.  We're at about 4.5 gph at NHMS.  Quite a bit worse than what we'd hoped. None the less, with our current config we could and should go to 5.5gph.  We're suffering on the straights and getting to 5.5 will still allow us to fuel once per day.  How to get to 5.5gph is our next challenge.  That and getting better with our oops'...

"We Got Screwed" NHMS 2017, 4th NHMS 2020,  4th NJMP 2021,
"Judges Choice" NHMS 2021,10th NJMP 2022, 3rd Thompson 2022
#847 Batmobile  aka-"Beulah"  search Squidrope Racing on Facebook

Re: Fuel consumption

Driving smoother aka carrying speed through the corners and less drag racing out of corners is only way.

Maybe go to Thompson on open track night and give your drivers set amounts of fuel in tank,  Set them loose and see who gets most laps and yet consistent and quick times.  It's endurance racing that seems like sprint racing some days.  NHIS has the two grades that make for more fuel consumption and fighting for corner entry position which eats more fuel.  IMO.

Re: Fuel consumption

I posted our best (worst?) fuel consumption ever this weekend.  After an hour and 45 minutes I came in with the engine sputtering.  Car took 20 gallons of gasoline.  That 460 is a thirsty beast.

Tunachuckers: 15 Years of Effluency
'08 - '10: 1966 Volvo 122, "Charlie"
'10 - '18: 1975 Ford LTD Landau --> 2018 - current: Converted into 1950 "Plymford"
'22 - current: 1967 Volvo 122, "Charlie ]["

Re: Fuel consumption

5 gallons/hour  -  Buick 3.8 with a Rochester Dual-Jet in a Triumph Stag

Everybody grab your brooms, it's shenanigans!

Re: Fuel consumption

2002 Acura RSX
We did a THIRSTY 8.5 gph at the fall Gingerman race. And that was trying to conserve as much as we could...we can't...lol.
It also lives between 6500 and 8000 rpm all the time. Makes it extra tough when our capacity is 13 gal.

Team BAD Company Endurance
Acura RSX #0
4 times losers, and counting...
"I got screwed" winners? 2018 Cure for Gingervitis, 5th on laps overall 2018 Elite meet to Cheat

Re: Fuel consumption

mechimike wrote:

I posted our best (worst?) fuel consumption ever this weekend.  After an hour and 45 minutes I came in with the engine sputtering.  Car took 20 gallons of gasoline.  That 460 is a thirsty beast.

460 seems like the number of gallons of fuel you'll need for a Lemons weekend.

Seriously, though, you probably need to slow the engine down and make use of the torque.
I'd want to spend most of my time between 2-3.5K RPM.

Capt. Delinquent Racing
RUST-TITE XR4Ti - '21 ARSE-FREEZE-APALOOZA  I Got Screwed
The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
'17 Vodden the Hell - (No) Hope for the Future Award, '08 AMP Survivor, '08 ARSE-FREEZE-APALOOZA Mega-Cheater

Re: Fuel consumption

DelinquentRacer wrote:
mechimike wrote:

I posted our best (worst?) fuel consumption ever this weekend.  After an hour and 45 minutes I came in with the engine sputtering.  Car took 20 gallons of gasoline.  That 460 is a thirsty beast.

460 seems like the number of gallons of fuel you'll need for a Lemons weekend.

Seriously, though, you probably need to slow the engine down and make use of the torque.
I'd want to spend most of my time between 2-3.5K RPM.

A 460 at 4500 RPM sounds soooooo good, though!

Tunachuckers: 15 Years of Effluency
'08 - '10: 1966 Volvo 122, "Charlie"
'10 - '18: 1975 Ford LTD Landau --> 2018 - current: Converted into 1950 "Plymford"
'22 - current: 1967 Volvo 122, "Charlie ]["

Re: Fuel consumption

I'm going to guess a little bit here, but I wouldn't think that weight would actually figure into it but rather a combination of torque used vs max torque and power output, and drivetrain efficiency. Basically it should come down to the wheel hp divided by all of the inefficiencies in the powertrain. This would be drivetrain losses but also fuel use losses. Basically, the way I brain it, if I make 100ft-lb up to 5 k then taper off to 70ft-lb at 6k, that represents an efficiency loss due to engine losses, so I should be making less torque for the same shot of gas. Multiply times number of power strokes and you get hp and fuel consumption over time proportionally. YMMV based on tune here.  Basically, my wild ass guess here is that the only real way to improve the fuel efficiency of your motor would be to try to keep it lower in the rev range.

The next big thing is the driver. The more you can be on throttle and in the power band, the faster you will go and the more fuel you will burn in the same time frame.

Owner of the Knights Templar Neon
A&D of middling proportions

Re: Fuel consumption

1964 Dodge Dart with slant six and 2-barrel carb: ~7 GPH average.

With a badly cross-blown head gasket and running on 3 cylinders but still pumping all 12 valves, more like 10-11 GPH.

Re: Fuel consumption

Peak fuel efficiency, AKA lowest Brake Specific Fuel Consumption (BSFC),
comes a few hundred RPM above peak torque, and then starts to
decrease the higher in the rev range you go. There are reasons to
exceed the  lowest BSFC (the point at which the engine uses the least
amount of fuel for the most power) RPM point, but those usually arise due to other
compromises necessary, e.g., avoiding an upshift to then downshift for the
next corner would be the main one we face.

As has been stated many times on this board, avoiding a pit stop does
more to move you up the leader board than dropping 2 seconds a lap
because you are looking for more HP.

Capt. Delinquent Racing
RUST-TITE XR4Ti - '21 ARSE-FREEZE-APALOOZA  I Got Screwed
The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
'17 Vodden the Hell - (No) Hope for the Future Award, '08 AMP Survivor, '08 ARSE-FREEZE-APALOOZA Mega-Cheater