87 octane?

Post by **occasional demons** » Fri Apr 23, 2010 9:46 am

DoubtedNeon wrote:i have heard that they are service free. thats what i heard.

Basically, yes. Until something gets into your tank and clogs it. Other than that, they can last for the life of the car, if you are lucky enough to get good clean fuel, and no one sabotages it.

darthroush · Post by **darthroush** » Fri Apr 23, 2010 6:23 pm

DoubtedNeon wrote:i have heard that they are service free. thats what i heard.

So is the transmission fluid...

Post by **racer12306** » Fri Apr 23, 2010 6:26 pm

Only in manual trans. Autos have a 48k replacement.

darthroush · Post by **darthroush** » Sat Apr 24, 2010 12:09 am

From the manual:

Fluid and Filter Changes
Automatic transmission fluid and filter should be changed as follows:
Maintenance schedule “A” — No change necessary.
Maintenance schedule “B” – Every 60,000 miles (96 000 km) change fluid and filter under the following conditions: Police, taxi, limousine, commercial type operation, or trailer towing where the vehicle is driven regularly for more than 45 minutes of continuous operation.

48,000 miles is listed for trailer towing, and 60,000 for "Police, taxi, limousine, commercial type operation" in the actual service schedules.

I'm on schedule "A," except for the more than 45 minutes continuously. I go over that every day. However, I never planned on leaving the transmission fluid in there forever either...

winter0991 · Post by **winter0991** » Tue May 04, 2010 4:23 pm

all i see is 87 on here. what about 85? thats what ive been using since ive owned this car

Post by **occasional demons** » Tue May 04, 2010 5:14 pm

If it is running fine with it, there is prolly not a problem. You might be losing a little power, due to the PCM pulling timing, but if you have an ATX, it may not be noticeable. The combustion process will be done a little sooner than with 87. That is about all the difference is.

I think 86 is about the lowest I've seen here. And it it hard to find. Mainly at those rare stations that offer about 5 or 6 grades of fuel, ranging from 86 to 93.

sneakers O'toole · Post by **sneakers O'toole** » Tue May 04, 2010 5:48 pm

BlackRoseRacing wrote:Our cars with basic bolt ons can run pretty good on 87 octane, the magnum engines require 91 or higher due to the performance components of the engine. The magnum motor can run 89 or less, but performance is downgraded as detonation may happen and the pcm will pull ignition timing.

what about what is basically a magnum engine running on a non-mag computer?

Post by **occasional demons** » Tue May 04, 2010 6:01 pm

sneakers O'toole wrote:
what about, basically a magnum engine running on a non-mag computer?

Basically, a pre NGC engine with a Magnum cam.

A Magnum spec engine running on a standard PCM may not make as much potential HP due to less timing available. The timing/fuel maps might be more aggressive on the Magnum PCM too?

With the '02 Magnum PCM, there is a noticeable difference at about 4900 rpm. I do not yet have the IM on my car, but at 4900 rpm, it feels as if something opens up. My guess is, it adds fuel/timing at that rpm to compliment the butterflies opening. The '01/NGC Magnum PCM's may be the same, but I can't say from personal experience.

Post by **racer12306** » Tue May 04, 2010 8:33 pm

85 octane is used in places of high altitude, like Denver. That is where I've seen it.

Post by **occasional demons** » Tue May 04, 2010 8:45 pm

That would make sense. Less air would need a faster burn. It's not like the engine is making full power at high altitudes.

sneakers O'toole · Post by **sneakers O'toole** » Tue May 04, 2010 9:17 pm

occasional demons wrote:
Basically, a pre NGC engine with a Magnum cam.

A Magnum spec engine running on a standard PCM may not make as much potential HP due to less timing available. The timing/fuel maps might be more aggressive on the Magnum PCM too?

that's what i'm thinking. i switched back to 87 today and i still chirp 2nd..and still feels just as tourquey, same as 89. like Dante said a few posts back, i figure as long as the computer is tuned for 87 i should just use 87.

occasional demons wrote: the '02 Magnum PCM, there is a noticeable difference at about 4900 rpm. I do not yet have the IM on my car, but at 4900 rpm, it feels as if something opens up. My guess is, it adds fuel/timing at that rpm to compliment the butterflies opening. The '01/NGC Magnum PCM's may be the same, but I can't say from personal experience.

i feel a little difference at 4900 with the mag mani...just not enough

Marcel · Post by **Marcel** » Wed May 05, 2010 3:50 pm

87, 85 octane.. damn!! in the netherlands you can only get 95 and 98, in germany there's still some gasstations with 91..

why are your octane levels so low, i wonder

Post by **racer12306** » Wed May 05, 2010 6:21 pm

It's a different rating system. If you look at your pump I believe you will see 98 RON octane.

We have RON + MON/2 numbers.

Marcel · Post by **Marcel** » Thu May 06, 2010 5:06 pm

indeed, all those numbers are RON..

and thanks to wikipedia, i know why the numbers are lower!

BlackRoseRacing · Post by **BlackRoseRacing** » Fri May 07, 2010 5:16 am

racer12306 wrote:Only in manual trans. Autos have a 48k replacement.

Severe duty, lot's of stop and go 15K on ATF+4
^^^Mail carriers, UPS drivers, severe in those cases
Average driving every 30K for ATF+4

Post by **racer12306** » Sat May 08, 2010 11:16 pm

BlackRoseRacing wrote:
racer12306 wrote:Only in manual trans. Autos have a 48k replacement.
Severe duty, lot's of stop and go 15K on ATF+4
^^^Mail carriers, UPS drivers, severe in those cases
Average driving every 30K for ATF+4

Not according to the FSM, it says 60k for auto trans fluid replacement. So I was wrong too, I thought I remembered a 48k interval.

fattycrack · Post by **fattycrack** » Sun May 09, 2010 12:54 am

i run 87 and when i engine break i blumble like a baby srt but on 91 or 93 i do not get the blumble soooo i choose to run 87 till i get my turbo on

BlackRoseRacing · Post by **BlackRoseRacing** » Sun May 09, 2010 10:06 am

racer12306 wrote:
BlackRoseRacing wrote:
racer12306 wrote:Only in manual trans. Autos have a 48k replacement.
Severe duty, lot's of stop and go 15K on ATF+4
^^^Mail carriers, UPS drivers, severe in those cases
Average driving every 30K for ATF+4
Not according to the FSM, it says 60k for auto trans fluid replacement. So I was wrong too, I thought I remembered a 48k interval.

I've seen too many trani's blown up pushing the fluid intervals over 30K. Hell even at 15K the fluid is broken down already....

Post by **racer12306** » Sun May 09, 2010 11:05 am

My sister's tranny is doing just fine after about 130k, even after a trans cooler incident, and I'm sure it was changed at intervals less frequent than 30,000 miles.

Post by **occasional demons** » Sun May 09, 2010 9:15 pm

Since we are off topic on ATX fluid...

Redline ATF FTW. Jeep recommends every 30,000 or something close to that in the AW4. At 30,000 the oem looked pretty dark. I have 71,000 on the Redline I put in at 30,000. It has been overheated to the point it was flowing out the dipstick tube. It is still clear and pink.

This is Dexron IIE designation, in synthetic form. I would go with their version of ATF+4 if I had a need for it. It really doesn't cost that much more these days. About $3 or $4 more a quart at the most.

winter0991 · Post by **winter0991** » Mon May 10, 2010 2:17 am

That makes perfect sense. I'm in Utah @ 5500ft. Never thought of that. Drove down to Sacramento, didn't see one 85 octane. Sac is at like 200ft.