89 octane recommend, does it really make a difference?

[grimreefer]

Never hauled anything heavier than about 3000# around the Florida flat lands and I can count the times I've floored it on three fingers. 87 since she left the lot and she's been a good girl.

 

[HSKR R/T]

From the manual. Does this mean don't use seafoam? I usually put a can every oil change. 1/2 into the vac line of the brake booster, and the other half in the tank.

You shouldn't need to add any seafoam on a brand new vehicle. Let alone every oil change. Get a catch can and there should never be a need to seafoam your engine

 

[CaptainCJ35]

Car and Driver did a pretty good test which includes a 5.7 Hemi...

Is Premium Gas Worth It? We Test High Octane on 4 Popular Vehicles

We tested higher octane fuel than manufacturers require on the Honda CR-V, BMW M5, Ford F-150, and Dodge Charger to see if it impacted acceleration or MPG.

www.caranddriver.com

 

[SD Rebel]

Car and Driver did a pretty good test which includes a 5.7 Hemi...

Is Premium Gas Worth It? We Test High Octane on 4 Popular Vehicles

We tested higher octane fuel than manufacturers require on the Honda CR-V, BMW M5, Ford F-150, and Dodge Charger to see if it impacted acceleration or MPG.

www.caranddriver.com

Holy smokes, the difference in premium to regular in the 3.5L F150 is impressive, I mean 0-60 in 5.3 seconds!

But the Hemi makes more sense for us here, there was an obvious difference, but nothing that we will likely notice with a 5,800 lbs truck.

 

[theblet]

You shouldn't need to add any seafoam on a brand new vehicle. Let alone every oil change. Get a catch can and there should never be a need to seafoam your engine

I have never run a catch can. Although I’ve used some pcv deletes. Not sure how the truck would react to this.

 

[CaptainCJ35]

I'm not sure how much value a catch can has for a port injected engine.

 

[HSKR R/T]

I have never run a catch can. Although I’ve used some pcv deletes. Not sure how the truck would react to this.

PCV delete isn't good for the engine, unless you switched to another way to scavenge from crank case. PCV isn't just about emissions

 

[HSKR R/T]

I'm not sure how much value a catch can has for a port injected engine.

If you've ever seen how much crap gets collected in them, you wouldn't want to go without.

 

[SKT Customs]

For what it’s worth, I was running 87 (because that’s what I always ran in my 5.7 challenger without any issues) and it was pinging a lot. I tried 89, still pinging but not as much. 91 and no pinging. Sucks that I have to pay for premium gas when the truck is meant to run on 89, but oh well I guess.

 

[CaptainCJ35]

If you've ever seen how much crap gets collected in them, you wouldn't want to go without.

Not saying there wasn't crap, just that the crap is a much bigger deal for turbo and direct injected engines. Port injected on the other hand uses the fuel to dissolve and burn the crap away during combustion.

 

[SD Rebel]

Yeah, I was told catch cans really are ideal for direct injected motors, many of which are also turbo charged, so pretty much covers both things.

I'm sure there is a positive to using it on a NA engine with multi-port injection, but maybe not enough to really cover the cost of can, but not bad if you just want one on there.

 

[HemiDude]

Used 88' Tacomas probably cost that much, lol.

Definitely agree with your statement, though I don't think in the short term 87 would hurt your engine, since the manual clearly states it's acceptable, but I don't think it will save you money in the long run and also who knows could lead to issues in the long term, with more engine deposits could lead to more knocking on 87 and some people just don't notice it.

It says in the manual that light knocking on 87 is ok, I rather not have any knocking at all.

Your statement makes me wonder if there is any correlation between fuel quality, octane rating, and cracked manifolds

 

[HemiDude]

Or one could just use 87 and use the saved money for a warranty. Over 125k miles, assuming you get a 1mpg bump with 89, you would save around $1,750 over those miles (depending greatly on difference in price of 87/89 in your area). For that cost you can go get a 7/Unlimited or 8/125k powertrain warranty. Then everything is covered on the powertrain regardless if it is caused by worse gas or not. If there is no gas mileage gain between the two you could probably afford a 8/125k bumper to bumper warranty.

Of course I am not one to own my truck 10+ years or put on 200k miles, so it is different for everyone.

The biggest difference I see in cost savings of fuel verses a long-term powertrain warranty is, I'd prefer not to be without my truck while it is in the shop getting a warranty engine

 

[RAM Patriot]

When I purchased the truck it came with 87 octane ethanol fuel. My first year of fill ups I used 87 octane non-ethanol and noticed some improvement in the gas mileage and power but the truck would still knock a little under loads. After I found another gas station that offered 90 octane non-ethanol fuel, the knocks went away and the gas mileage and performance improved.

I'm averaging 18.6 MPG on this regiment.

The 90 Octane non-ethanol is about 30 cents more per gallon but between the increase in 2-3 MPG increase and the performance and less wear and tear on the motor it is worth it to me.

I plan on putting some miles on this truck. She's a keeper.

 

[HSKR R/T]

Not saying there wasn't crap, just that the crap is a much bigger deal for turbo and direct injected engines. Port injected on the other hand uses the fuel to dissolve and burn the crap away during combustion.

Problem is, that's not how it works. Even MPFI engines develope deposits on the combustion chamber from that crap being sucked in and burned. Unless you are washing down the cylinder from running super rich that is.

 

[Orion10182011]

The ECU will pull timing if it detects knock from low octane gas. That said knock likely isn't an issue with most regular driving. Towing and hard acceleration then yes the better gas makes a difference. Because pulling timing means less power.

 

[Amazing93]

Like many others have said in this post I use top-tier costco 91 octane. Use my costco card and get 4% cash back and it's damn near the price of crappy 87 safeway gas. If the engineers who built the motor say a higher octane is best I'm in no position to argue or second guess. I'm sure it has advantages my non engineering brain don't comprehend.

 

[CaptainCJ35]

Problem is, that's not how it works. Even MPFI engines develope deposits on the combustion chamber from that crap being sucked in and burned. Unless you are washing down the cylinder from running super rich that is.

I think we both agree that there is crap that gets caught by the can, I just don't think the value of putting one in is any where near the same when compared to more modern engine designs with direct injection or turbos or both. I guess if I were towing/hauling 30 - 50K miles per year, then ya... catch can is a good call. Just my opinion of course.

 

[HSKR R/T]

I think we both agree that there is crap that gets caught by the can, I just don't think the value of putting one in is any where near the same when compared to more modern engine designs with direct injection or turbos or both. I guess if I were towing/hauling 30 - 50K miles per year, then ya... catch can is a good call. Just my opinion of course.

Cost is negligible. Can get a good catch can for under $100, my unbranded UPR style was $60. Well worth the added protection it provides for long term engine health. no different than choosing to use a specific brand of oil or gas that might be a little more expensive.

 

[BigD]

Run 87 all the time. Usually Top Tier. Never had a problem. Salesman even said he runs 87 in his. If u ever have a warranty issue u will be covered running 87 all the time. So why bother paying more for 89 or 91 ?