Detergents are 90% waste of money in a well tuned engine with regular oil and filter changes. They only add all that crap because they know people will not perform proper maintenance.

 

Todays gasoiline is actually of a lesser quality than that from 1980. Carburetors could not handle any dirt or other contaminates.
The needles would get clogged and all hell would break loose.
Fuel injectors are not that picky, thats why there are no fuel filters, not to mention that the fuel is pushed through at such high pressure any grit is pulverized when it passes through the injector screen.

 

We only have 91 here in AZ so I usually alternate between 89 and 91 between fill ups, although I can't fill it all the way due to a leak I have yet to get to either on the filler neck or return line, prob neck.

With that being said, I usually run a bottle of lucas FI cleaner once a month too, not too sure if it does any good but with 91 running 4/gal, it's about the same price to run a bottle of cleaner once a month.

 

Injector cleaner is a waste of money, save your $4 per bottle and buy a extra gal of fuel.

 

I think the detergents in injector cleaner are effective -- however, it's totally uneconomical to buy them by the bottle. It's far more cost effective to add them when they formulate the fuel. It's like designer brand-name bottled water versus tap. Of course you're going to mix them, so if your tap is bad, there's really nothing you can mix in it to make it better. If it's good, there's really no reason to mix anything in it either.

 

Can I suggest it be standard practice to put people on "forum probation" when they start up a "what octane should I use" thread?

 

AMEN!!!!!! Premium (93 - 91) is roughly $0.10 more per gallon than mid-grade (90 - 89).

Let's also assume you are a ding-dong and run your tank down until the light comes on (bad for pump). So, we are looking at a 20 gallon fill up. $2 per tank difference. Between $100 and $200 per year difference.

If owning a 12 to 14 MPG truck and $2 - $4 per week is hurting you to fill your rig with a quality product that 90% of Rover owners will tell you does make a difference in performance and engine longevity, then you are totally driving the wrong vehicle.

 

LMAO...

I only brought up the injector cleaner since I've only owned it 2mos and it had the slightest rough idle. Ran 2 bottles through it at 91 and cleaned it right up, did run a 1/2 tank of 89 through it a couple of times to see the diff. Now I'm running only 91 through it have been for the last month.

Spike, I also changed over to Rotella 15/40 with a better larger oil filter, wow, it actually made quite the difference, thanks.

 

Hmm so Spike and myself are not alone in switching to Rotella diesel oil. But larger oil filter? What size and do you have the exact part number so I can try it out? Currently I'm content with a Bosch filter found at any local autozone, but I'd be more than happy to try a bigger Bosch filter.

 

I noticed people really are against 87 octane. While I have mostly run 91 out of habit I decided to look into it since I found it odd such an old design / low compression engine needed 91.

According to RAVE there are two different compression ratio's for my motor (4.0L). That is news to me. These are the octane recommendations according to RAVE.

9.35:1 - 95 RON (91 AKI)
8.13:1 - 91 RON (87 AKI)

Seeing as how AKI is the North American pump spec, why is it everyone pushes 91 so firmly without knowing the users motor. Was the low compression motor never sold in this market?

I'll still always run 91 it is more curiosity.