High Speed Runs

[Race Red Boss]

I had read somewhere that sustained high speed runs going into 5th/6th gear were not recommended on the 03-04 Cobra's. Can't recall if it had to due to potential supercharger issues or gearing/tranny??

If true, wondering if that also applies to our GT500's?

 

[Catmonkey]

Sure it does. I blew a head gasket at the Texas Mile quite a while ago, hence the built engine in my signature. If you're going to do sustained high speed runs have more than enough octane in the tank and a way to monitor IAT2 temps.

 

[fullboogie]

The load on the engine at WOT in 5th or 6th is unreal with a real danger of detonation. Cat is right, good octane, good tune, gauges.

 

[2011 gtcs]

I know the 13/14s do better in 5th gear at high speed runs than the 12s and older, but its still not a good idea, my car in 5th gear is over 170mph so I'm not doing that to often. But if you plan on it i would have either MS100, MS109 or E85 and a trunk mounted ice tank is a good idea.

 

[MG0h3]

The main issue is heat combined with tight piston to cylinder fitting in the 03/04s. The long duration pull in 5th/6th creates a ton of heat and the pistons can swell and scuff the cylinders.

 

[Catmonkey]

It's not the pistons as much as the rings. Once the rings expand, if the ends butt, it's game over.

 

[merkyworks]

I know the 13/14s do better in 5th gear at high speed runs than the 12s and older,

This make since with Ford toting 200 mph capable for the 13/14s.

 

[2011 gtcs]

This make since with Ford toting 200 mph capable for the 13/14s.

Yeah, the cylinder heads, factory manley pistons, head gaskets, cooling system and intercooler system help a lot.

 

[KENS96M6]

They also added piston oil jets to cool the underside of the piston on the 13 and 14 gt500.

 

[2011 gtcs]

They also added piston oil jets to cool the underside of the piston on the 13 and 14 gt500.

True, it's crazy how many little things got added into the 13/14s.

 

[LouieMooo]

Wait so if I converted to E85 that would definitely help the situation? Not that I'm doing high speed runs, but just to be on the safe side? 03 BTW

Sent from my SM-G965U using the svtperformance.com mobile app

 

[Catmonkey]

Wait so if I converted to E85 that would definitely help the situation? Not that I'm doing high speed runs, but just to be on the safe side? 03 BTW

There's no doubt E85 has a lot of octane, but it comes at a cost of a return style fuel system and bigger injectors, significantly reduced mileage and more maintenance. Availability is also a big consideration based on your location. It's not for everyone. Sure it's a solution, but is it a practical solution based on where you live and how you use your car. For me, using race gas is a better solution if I want to go hog wild and/or bump up the bost. The rest of the time it's pump gas and a conservative tune.

 

[LouieMooo]

There's no doubt E85 has a lot of octane, but it comes at a cost of a return style fuel system and bigger injectors, significantly reduced mileage and more maintenance. Availability is also a big consideration based on your location. It's not for everyone. Sure it's a solution, but is it a practical solution based on where you live and how you use your car. For me, using race gas is a better solution if I want to go hog wild and/or bump up the bost. The rest of the time it's pump gas and a conservative tune.

Its readily available where I live and I don't have to drive the car all the time if I don't want to, so that's why I've been looking into it. Thank you for the reply

Sent from my SM-G965U using the svtperformance.com mobile app

 

[Catmonkey]

This is a good source to see if it could work for you. E85 Gas Station Locations and Alternative Fuel Information According to this site, there are 4 stations in the entire state of Louisiana.

 

[boduke0220]

E85 is Definitely the way to go. On my Previous tvs coyote I did 156mph in the half mile on 93 octane. with just a switch to E85 I went 165. its good shit.

 

[einehund]

I have literal hours in 5th gear at 160mph plus (love the autobahn). Never had any issues except for the rear end overheating and belching gear oil out the vent on the axle. I solved that with a KR style axle reservoir.

 

[boduke0220]

I have literal hours in 5th gear at 160mph plus (love the autobahn). Never had any issues except for the rear end overheating and belching gear oil out the vent on the axle. I solved that with a KR style axle reservoir.

What kind of gas mileage do you get at that speed lol

 

[einehund]

2.3 mpg @175mph. I hit the reset button while on one of the runs!

 

[RedVenom48]

Its readily available where I live and I don't have to drive the car all the time if I don't want to, so that's why I've been looking into it. Thank you for the reply

Sent from my SM-G965U using the svtperformance.com mobile app

The real magic with Ethanol is its direct ability to cool the air/fuel mixture. It does have a little higher octane than premium, but its the other latent properties of the fuel that allows it to resist detonation and take timing and boost etc better than pump and some race fuels.

Purpose made race fuels are "technically" better as they offer the same detonation resistances as E85 but have more energy per unit. You need roughly 30% more fuel with E85 than pure race fuel/ non-Ethanol blend gasoline. Then again, when race fuel's cost 4x more than E85 per gallon, its VALUE for its performance is what makes it a winner.

Yes, there is no getting around the enormous investment that ethanol takes to run in our GT500s (13-14 GT500s excluded). Yes, it has less fuel mileage than race fuel/pump gas. But in places where its easily available, $2-$3 a gallon is pennies for a fuel that wil let you run big boost and timing with pump availability. I went back and forth on it a lot recently, also trying to find cheaper ways of running it. In the end, the cost of a stand alone fuel system is offset by the overall properties of ethanol and being available at more pumps than race fuel.

Check out The Distillery section here at SVTP for dedicated discussion of Ethanol and other races fuels:

https://www.svtperformance.com/forums/the-distillery.374/

 

[RedVenom48]

2.3 mpg @175mph. I hit the reset button while on one of the runs!