need help

darkstang · 02-14-2007, 12:40 AM

I Just bought a 98'mustang gt 4.6L but I dont know if it is the sohc or the dohc and I need to know what is the best octane fuel to put in it

Jeff Chambers · 02-14-2007, 06:54 AM

A GT is a SOHC 4.6L. Factory calibration is based on 87 octance fuel. The better fuel you can run, the better for the car IMHO. If you run 93 all the time, then you can have the car re-calibrated/tuned to make use of the extra octane.

Coupe50h · 02-14-2007, 10:50 AM

Run 87 unless you get some mods like a timing adjuster or custom chip and a power adder.
Hey wait this is the windsor forum

USMC302 · 02-14-2007, 01:51 PM

You want to run the lowest you can get away with without pinging.

02-19-2007, 09:32 AM

I am basically new here and a first time Mustang GT owner. 2004 4.6L.
The mfg said 87 octane would be fine. But I already added premium 93 oct should I just go back to 87oct, I'd just thought that running higher octane would make for better performance...am I wrong?

Also I drove 115 miles (last time I do that(Trying to keep mileage low)) to NY from Pa and it only used up a 1/4 of my tank

that's great!!!

p.s. What is IMHO, Jeff Chambers? Thanks again

darkstang · 02-19-2007, 02:35 PM

i just put in 92 octane and try it then put in 97 octane and it smoothed it out

darkstang · 02-19-2007, 02:39 PM

oh and you dont want to run the lowest octane you can unless you have some weird motor in it. higher is better, if the motor is a high output motor that is.

The Deuce · 02-20-2007, 01:22 AM

Quote:

Originally Posted by darkstang

oh and you dont want to run the lowest octane you can unless you have some weird motor in it. higher is better, if the motor is a high output motor that is.

Octane is the measure of fuels resitance to combustion. You want the fuel to burn as efficiently as possible without pre-ignition. This means running the lowest possible octane.

I don't know where you live but I've never heard of 92 or 97 octane fuel.

If you run a higher octane than you need, it won't all burn off and you'll end up with carbon deposits in your motor. That's bad news.

blue00gt · 02-21-2007, 05:13 PM

Quote:

Originally Posted by The Deuce

Octane is the measure of fuels resitance to combustion. You want the fuel to burn as efficiently as possible without pre-ignition. This means running the lowest possible octane.

I don't know where you live but I've never heard of 92 or 97 octane fuel.

If you run a higher octane than you need, it won't all burn off and you'll end up with carbon deposits in your motor. That's bad news.

Bingo. The only reason to run higher octane would be if you have advanced timing or higher compression that requires the extra octane. You will not make any more power just by putting in higher octane gas unless your car was set up to run it.

02-21-2007, 06:58 PM

Even though I didn't start this thread, I appreciate the tip on octane. Thanks all

. I went back to what the mfg said I should put in it: Regular Unleaded

02-14-2007, 12:40 AM	#1
darkstang darkstang98 Join Date: Feb 2007 Location: oregon Posts: 6	need help I Just bought a 98'mustang gt 4.6L but I dont know if it is the sohc or the dohc and I need to know what is the best octane fuel to put in it

02-14-2007, 06:54 AM	#2
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	Re: need help A GT is a SOHC 4.6L. Factory calibration is based on 87 octance fuel. The better fuel you can run, the better for the car IMHO. If you run 93 all the time, then you can have the car re-calibrated/tuned to make use of the extra octane. __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"

02-14-2007, 10:50 AM	#3
Coupe50h Registered Member Join Date: Aug 2002 Location: SanAntonio, Tx Posts: 957	Re: need help Run 87 unless you get some mods like a timing adjuster or custom chip and a power adder. Hey wait this is the windsor forum __________________ X-Texas highway patrol ssp 1990 coupe - exploder Gt-40 iron heads, Explorer intake, 19 lber's. E-cam. crane 1.7 rollers. 190fp. 75mm maf. 65mm tb, tubular subframe connectors, mac cai, Asp crank pulley, T-5, king cobra clutch, flowtech 1-5/8 unequals, mac X-pipe Frpp driveshaft, lakewood Lca's. race weight 3,160 12.69 @ 107.35, 1.71 60' 26x8.5 drag's 3.90 gear 13.20 @ 106.91 - 235/60/15 firestones 2.3 60' 3.27 gear

02-14-2007, 01:51 PM	#4
USMC302 Registered Member Join Date: Apr 2001 Location: Gallatin, Tn Posts: 1,326	Re: need help You want to run the lowest you can get away with without pinging. __________________

02-19-2007, 09:32 AM	#5
amongtheliving Guest Posts: n/a	Re: need help I am basically new here and a first time Mustang GT owner. 2004 4.6L. The mfg said 87 octane would be fine. But I already added premium 93 oct should I just go back to 87oct, I'd just thought that running higher octane would make for better performance...am I wrong? Also I drove 115 miles (last time I do that(Trying to keep mileage low)) to NY from Pa and it only used up a 1/4 of my tank that's great!!! p.s. What is IMHO, Jeff Chambers? Thanks again

02-19-2007, 02:35 PM	#6
darkstang darkstang98 Join Date: Feb 2007 Location: oregon Posts: 6	Re: need help i just put in 92 octane and try it then put in 97 octane and it smoothed it out

02-19-2007, 02:39 PM	#7
darkstang darkstang98 Join Date: Feb 2007 Location: oregon Posts: 6	Re: need help oh and you dont want to run the lowest octane you can unless you have some weird motor in it. higher is better, if the motor is a high output motor that is.

02-21-2007, 06:58 PM	#10
amongtheliving Guest Posts: n/a	Re: need help Even though I didn't start this thread, I appreciate the tip on octane. Thanks all . I went back to what the mfg said I should put in it: Regular Unleaded