92 Octane in Renix Engine, if anyone cares

I experiment with fuel grades every now and then. My last truck had SoCal emissions. That, coupled with the lower density air up here and corresponding lower octane fuels (85, 87, 91) made it necessary to run premium. Otherwise it knocked horribly(so bad that the dealership changed the timing chain, warranty item) and had noticeably reduced power. I also noticed improved MPG when on the high-test stuff. Even if that part was just in my mind, the performance differences were not. It wouldn't get up the I-70 hill to the mountains without grabbing a gear(to 4th) unless I ran premium. On 91 octane it would, traffic allowing.
 
ceb0217 said:
I live with in an hour of the coast so getting sea foam is easy, but isnt the salt bad for the fuel system??? and how about the people that live farther away can you just foam up water and sea salt ??? if so what kind of mix do I use ??? 1table spoon to a gal of water??? and then how do I "foam it up" mabe a little soap????
Click to expand...

Really? Pay attention junior! :roflmao:
 
how bout I just turn my snorkle upside down and go along the beach really carefull so I dont suck up any sand??? or would the sand help with the low compression by sanding down the bores so the rings seal better??? and wouldnt it clean the carbon off the valves with the sand??? so mabe actual sea foam from the ocean is better than making my own. but what if I accdently suck up a crab??? I really dont think I want my XJ to have crabs. oh sorry for the hijack I for got to use the search feature.
 
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Actually the sand will port and polish your intake and cylinder heads. Make sure suck it in via a vacuum hose at a rate of 1lb per hour, NOTHING MORE or youll ruin it, and youll be amazed at the performance gains.
 
swbooking said:
Actually the sand will port and polish your intake and cylinder heads. Make sure suck it in via a vacuum hose at a rate of 1lb per hour, NOTHING MORE or youll ruin it, and youll be amazed at the performance gains.
Click to expand...

How much would it increase my mpgs? Right nowz im at round 12 or sumting.
 
it would easily kick you up to about 23-24 mpgs.

I did this on my Prius and im now up to about 60mpgs. Its amazing.

I also got a gain of about 37.5 whp. and thats dynoed at the wheels :D
 
There is a process for smoothing intake manifolds, called "extrude honing" or something of the sort, in which you jam a paste of abrasives through. It's sheer genius to accomplish this on a running engine, and with luck you can polish your cylinder walls in the process, all at no cost. I only regret that I live so far inland in clay country. On the other hand we have a lot of very dirty snow right now, so perhaps if I use that I'll get the benefit of polishing and cooling all in one. :laugh3:
 
Snow foam can be used the same as sea foam. 30% snow and 30% sand with 40% gumout works the best for me. This must be done at 5000 RPM for it to be effective. Try to stay away from the yellow snow.
 
is this a one time thing cuse wont running sand in the converter turn it into glass?? or if I remove the converter will it also port and polish the exhaust pipe and muffler??? woooohoooooo we might have just found a way to polish a turd from the inside out!!!!! no one had a thought about the crabs???? if running veggy oil in a diesel makes it smell like fries or dougnuts will sucking up crabs make the exhaust smell like sea food??? or does the jeep just get a nasty STD ???? and should any of this be done with 92 octane or just 87
 
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Forums are so helpful. Premium is a slower burning fuel designed for high compression engines if you did not build your engine for premium it should not be used. If you need a basic understanding of octane ratings go here or do a search and you will find plenty of information. Additives are a waste of money and things like seafoam can be harmful to your engine. If your engine is stock please do not use high octane fuel.
 
hey there "mesh"

seafoam has been around since you were a twinkle in your daddy's eye and is a great product that can be used to clean a tired old injection system, as well as other uses. I swear by it.

So let me ask you this.. When your injector rail and injectors are gummed from sitting unused what do you use to clean them? Seafoam is NOT a waste of money if your truck needs it.
 
Back to the real topic. I dont really count gas mileage, too lazy. But i have far less knocks than with 87 Octane. Acceleration seems to take longer, but it could just be less noise. (I associate noise with acceleration cause of the knocks) I think I might try the seafoam thing.
Always added STP Gas treatment and whatever injector cleaner the gas station had to the 87 octane. Sometimes I would add some Octane additive. Not really sure if it works cause I havent ran an "untreated" tank yet.
 
Ritter4.0 said:
Back to the real topic. I dont really count gas mileage, too lazy. But i have far less knocks than with 87 Octane. Acceleration seems to take longer, but it could just be less noise. (I associate noise with acceleration cause of the knocks) I think I might try the seafoam thing.
Always added STP Gas treatment and whatever injector cleaner the gas station had to the 87 octane. Sometimes I would add some Octane additive. Not really sure if it works cause I havent ran an "untreated" tank yet.
Click to expand...

I have seen posted in this thread that 91 octane will harm the 4.0. That is so very false. I use 91/92 octane often when;

1) 89 is not available or
2) If the 4.0 knocks on aceleration or going up hill (usually associated with bad/poor quality gas.

Yes, it is true the 4.0 do not benefit from the higher octane, compression too low;... as a matter of fact, there is a notably (according to the butt dyno) lower level of performanance when using the high octane fuel.

Sea Foam works wonders when added to gasoline and fed to a 250,000+ miles 4.0 XJ engine.

Did I mention the regular use of Sea Foam also reduce or eliminate engine knocks?
 
i seem to get better mpgs outa the lower octane gas in my 91.
my ol man swears by seafoam tranny treatment. and the fuel treatment. its some good stuff. either that or lucas.
i never really notice anything out of the other treatments like stp or gumout
 
ceb0217 said:
how bout I just turn my snorkle upside down and go along the beach really carefull so I dont suck up any sand??? or would the sand help with the low compression by sanding down the bores so the rings seal better??? and wouldnt it clean the carbon off the valves with the sand??? so mabe actual sea foam from the ocean is better than making my own. but what if I accdently suck up a crab??? I really dont think I want my XJ to have crabs. oh sorry for the hijack I for got to use the search feature.
Click to expand...

OOO! I love fresh crab! Very expensive here. But the snorkle idea is pure genius. I'm off to the beach. Gotta stop for white wine and french bread first.
 
ceb0217 said:
I live with in an hour of the coast so getting sea foam is easy, but isn't the salt bad for the fuel system??? and how about the people that live farther away can you just foam up water and sea salt ??? if so what kind of mix do I use ??? 1table spoon to a gal of water??? and then how do I "foam it up" maybe a little soap????
Click to expand...

Seconded
 
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