Gasoline/Fuel Question - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Visibilities · 08-09-2018, 04:24 PM

So to summarize a long story, my car has been parked for 4 months with about half a tank of pure 91 in it. I'm getting a new motor put in and the shop who's doing it claims the fuel will be good for startup and mild driving; 1-4(ish)K RPM. My research has me worried that the car won't like the fuel, and in worst case, something bad will go wrong. He's also doing a 2-bar map tune for the low RPMs on this old gas. By the time the car is running it will be exactly 4 months. The car has sat outside for at least half of the time in the heat. Do you guys think it would be alright for the small stuff? Or should I sternly convince him to drain it? Thanks. - Vis

Sinister10 · 08-09-2018, 04:30 PM

What’s being done to the new motor? Stock or built?

Visibilities · 08-09-2018, 04:34 PM

Darton sleeved 427 with forged everything

Sinister10 · 08-09-2018, 04:38 PM

Compression? And what did your research say?

Visibilities · 08-09-2018, 04:43 PM

10.2:1 with a D1SC procharger on *about* 10lbs of boost. I've heard anywhere from "gas being unsuitable for use within 30 days" to "a year". Even if the gas is still 'usable' I'm still worried it's slightly different burn properties will skew the tune off. Idk, I'm paranoid.

Sinister10 · 08-09-2018, 04:46 PM

At that compression I don’t think I’d be too concerned, if you were 11.5-1 or higher, I’d have them drain the old stuff. How much gas is in it? At the very least, I’d have them detune it till all the old gas is out

Visibilities · 08-09-2018, 04:49 PM

I'd say about half a tank. He isn't doing the heavy pulls on the Dyno with that gas, he even said he'd drain it at that point. He's just doing the drive-around tune on it. I just don't see why he can't drain it now and start fresh while he said he'd drain it if there was any left for the Dyno pulls...

Sinister10 · 08-09-2018, 04:56 PM

Quote:

Originally Posted by Visibilities

I'd say about half a tank. He isn't doing the heavy pulls on the Dyno with that gas, he even said he'd drain it at that point. He's just doing the drive-around tune on it. I just don't see why he can't drain it now and start fresh while he said he'd drain it if there was any left for the Dyno pulls...

I will agree that if he is willing to drain it before the heavy pulls, then why not just do it now and get it over with.

Visibilities · 08-09-2018, 05:18 PM

I don't know either. I just have my concerns. Even if it's still good I'm not sure how differently it will act.

Sinister10 · 08-09-2018, 05:22 PM

Have you done business with this shop before? Do you trust them and their capabilities?

Visibilities · 08-09-2018, 05:51 PM

I haven't done business before. I do trust his capabilities. He's been doing it for 14 years and says he's had cars sit for much longer and done them just fine. I just don't feel like lighting a pile of $20k on fire if you get what I mean.

Sinister10 · 08-09-2018, 06:00 PM

I feel ya. I don’t think I’d worry about as much as you are.

I’ve had a car that sat for almost 2 years and it ran ok with the gas that was in it when I parked it. 1972 Monte Carlo with a 402 big block.

*SSE 4 2SS* · 08-09-2018, 06:05 PM

Quote:

Originally Posted by Visibilities

I haven't done business before. I do trust his capabilities. He's been doing it for 14 years and says he's had cars sit for much longer and done them just fine. I just don't feel like lighting a pile of $20k on fire if you get what I mean.

It'll be fine. I usually try to run almost all of the fuel out of my car before heading to the shop, but I had my tank sit half full for well over six months.... No issue....

We drove it low RPM's until we had 500 miles.... mixing fuel in over time as we needed it, which wasn't long as my car gets about 3 mpg if I drive it very calmly and keep it out of boost.... Then at 500 miles, we put race fuel in it and started trashing on the dyno....

For what you are doing it it's all good... My personal opinion based on my experience...

Overflow · 08-09-2018, 06:35 PM

My rule of thumb is 6 months and it'll be good. Any longer than that and it'll need to be drained.

08-09-2018, 04:24 PM	#1
Visibilities Drives: 2014 SS - Sleeved 427/Procharged Join Date: Mar 2017 Location: Central Oklahoma Posts: 109	Gasoline/Fuel Question So to summarize a long story, my car has been parked for 4 months with about half a tank of pure 91 in it. I'm getting a new motor put in and the shop who's doing it claims the fuel will be good for startup and mild driving; 1-4(ish)K RPM. My research has me worried that the car won't like the fuel, and in worst case, something bad will go wrong. He's also doing a 2-bar map tune for the low RPMs on this old gas. By the time the car is running it will be exactly 4 months. The car has sat outside for at least half of the time in the heat. Do you guys think it would be alright for the small stuff? Or should I sternly convince him to drain it? Thanks. - Vis

08-09-2018, 04:30 PM	#2
Sinister10 Drives: 2010 Camaro SS Join Date: Jul 2018 Location: Indiana Posts: 543	What’s being done to the new motor? Stock or built? __________________ 2010 2SS/RS 6M, MGW flatstick, CAI cold air intake, SLP loudmouth 2 axleback, TSP 1 7/8 headers w/ hfc, pfadt 1" springs, SRP pedals, emblempros "6.2L" emblems on hood, ZL1 grill, M/T SC-5 wheels, nitto motivo 275f 315r. ZL1 addons wickerbill, smoked lenses, resonator delete x pipe, diode dynamics DRLs 1LE suede steering wheel, mighty mouse CC. SCTX4 and Dyno Steve tune.

08-09-2018, 04:38 PM	#4
Sinister10 Drives: 2010 Camaro SS Join Date: Jul 2018 Location: Indiana Posts: 543	Compression? And what did your research say? __________________ 2010 2SS/RS 6M, MGW flatstick, CAI cold air intake, SLP loudmouth 2 axleback, TSP 1 7/8 headers w/ hfc, pfadt 1" springs, SRP pedals, emblempros "6.2L" emblems on hood, ZL1 grill, M/T SC-5 wheels, nitto motivo 275f 315r. ZL1 addons wickerbill, smoked lenses, resonator delete x pipe, diode dynamics DRLs 1LE suede steering wheel, mighty mouse CC. SCTX4 and Dyno Steve tune.

08-09-2018, 04:46 PM	#6
Sinister10 Drives: 2010 Camaro SS Join Date: Jul 2018 Location: Indiana Posts: 543	At that compression I don’t think I’d be too concerned, if you were 11.5-1 or higher, I’d have them drain the old stuff. How much gas is in it? At the very least, I’d have them detune it till all the old gas is out __________________ 2010 2SS/RS 6M, MGW flatstick, CAI cold air intake, SLP loudmouth 2 axleback, TSP 1 7/8 headers w/ hfc, pfadt 1" springs, SRP pedals, emblempros "6.2L" emblems on hood, ZL1 grill, M/T SC-5 wheels, nitto motivo 275f 315r. ZL1 addons wickerbill, smoked lenses, resonator delete x pipe, diode dynamics DRLs 1LE suede steering wheel, mighty mouse CC. SCTX4 and Dyno Steve tune.

08-09-2018, 05:22 PM	#10
Sinister10 Drives: 2010 Camaro SS Join Date: Jul 2018 Location: Indiana Posts: 543	Have you done business with this shop before? Do you trust them and their capabilities? __________________ 2010 2SS/RS 6M, MGW flatstick, CAI cold air intake, SLP loudmouth 2 axleback, TSP 1 7/8 headers w/ hfc, pfadt 1" springs, SRP pedals, emblempros "6.2L" emblems on hood, ZL1 grill, M/T SC-5 wheels, nitto motivo 275f 315r. ZL1 addons wickerbill, smoked lenses, resonator delete x pipe, diode dynamics DRLs 1LE suede steering wheel, mighty mouse CC. SCTX4 and Dyno Steve tune.

08-09-2018, 04:34 PM	#3
Visibilities Drives: 2014 SS - Sleeved 427/Procharged Join Date: Mar 2017 Location: Central Oklahoma Posts: 109	Darton sleeved 427 with forged everything

08-09-2018, 04:43 PM	#5
Visibilities Drives: 2014 SS - Sleeved 427/Procharged Join Date: Mar 2017 Location: Central Oklahoma Posts: 109	10.2:1 with a D1SC procharger on about 10lbs of boost. I've heard anywhere from "gas being unsuitable for use within 30 days" to "a year". Even if the gas is still 'usable' I'm still worried it's slightly different burn properties will skew the tune off. Idk, I'm paranoid.

08-09-2018, 04:49 PM	#7
Visibilities Drives: 2014 SS - Sleeved 427/Procharged Join Date: Mar 2017 Location: Central Oklahoma Posts: 109	I'd say about half a tank. He isn't doing the heavy pulls on the Dyno with that gas, he even said he'd drain it at that point. He's just doing the drive-around tune on it. I just don't see why he can't drain it now and start fresh while he said he'd drain it if there was any left for the Dyno pulls...

08-09-2018, 05:18 PM	#9
Visibilities Drives: 2014 SS - Sleeved 427/Procharged Join Date: Mar 2017 Location: Central Oklahoma Posts: 109	I don't know either. I just have my concerns. Even if it's still good I'm not sure how differently it will act.

08-09-2018, 05:51 PM	#11
Visibilities Drives: 2014 SS - Sleeved 427/Procharged Join Date: Mar 2017 Location: Central Oklahoma Posts: 109	I haven't done business before. I do trust his capabilities. He's been doing it for 14 years and says he's had cars sit for much longer and done them just fine. I just don't feel like lighting a pile of $20k on fire if you get what I mean.

08-09-2018, 06:00 PM	#12
Sinister10 Drives: 2010 Camaro SS Join Date: Jul 2018 Location: Indiana Posts: 543	I feel ya. I don’t think I’d worry about as much as you are. I’ve had a car that sat for almost 2 years and it ran ok with the gas that was in it when I parked it. 1972 Monte Carlo with a 402 big block. __________________ 2010 2SS/RS 6M, MGW flatstick, CAI cold air intake, SLP loudmouth 2 axleback, TSP 1 7/8 headers w/ hfc, pfadt 1" springs, SRP pedals, emblempros "6.2L" emblems on hood, ZL1 grill, M/T SC-5 wheels, nitto motivo 275f 315r. ZL1 addons wickerbill, smoked lenses, resonator delete x pipe, diode dynamics DRLs 1LE suede steering wheel, mighty mouse CC. SCTX4 and Dyno Steve tune.

08-09-2018, 06:35 PM	#14
Overflow Space Shuttle Aficionado Drives: 2016 Camaro 2SS Join Date: Jun 2010 Location: Tampa, FL Posts: 30,899 View My Garage	My rule of thumb is 6 months and it'll be good. Any longer than that and it'll need to be drained. __________________