2015 Mustang Ecoboost K/SA?

[davidhuff]

2015 Ford Mustang Ecoboost Auto on craigslist Portland Oregon for $17,500 if interested?

[Bobby Lundholm]

Originally Posted by 6130

I don't think you'll need the rear axles for a Stock Eliminator type car.

And I'd run the numbers before purchasing the 4.09 ring & pinion- the power peak on the Ecoboost engine is only at 5,500 rpm. First gear is so deep, that you'd have a pretty steep launch ratio even with the stock gearing. And turbo engines tend to be more tolerant of taller gearing anyway.

I would use the stronger half shafts regardless. Especially using slicks and shocking the rear end at the launch. With the stiffer gear and it shifting into over drive I would think the 4.09 gear should work fine.

[6130]

Originally Posted by Bobby Lundholm

With the stiffer gear and it shifting into over drive I would think the 4.09 gear should work fine.

If you were going to switch to a C4, then the 4.09 might be needed, but if you're using the stock 6R80 transmission, I'd gear it to go through in 4th and leave it.

The 6R80 transmission has a 4.17 first gear. If you combine that with a 4.09 ring & pinion, that would give you a launch ratio equivalent to running a C4 with a 6.50 rear gear. I just don't think that's necessary for an engine that makes almost all of it's torque by about 2,500 rpm.

The calculations I ran, had the car going through in 4th gear, which is 1.14. 5th gear is .87, and 6th gear is .69. This engine makes so much torque and has such a wide powerband, with a horsepower peak at a relatively low 5,500 rpm, I don't think it would need to use that many gears to get down the quarter mile efficiently.

With a 30" tire, a 3.73 ring & pinion, and a 1.14 4th gear, the car would do just about 115 mph at 5,500 rpm through the lights.

With a 28" tire and the stock Performance Package 3.55 rear end gears, it would do 113 mph at 5,500 rpm in 4th.

With a 28" tire and the stock non Performance Package 3.31 rear end gears, it would do about 115 mph at about 5,300 rpm in 4th.

I'd be tempted to try it with a 28" tire and the stock gearing.

[6130]

Originally Posted by Bobby Lundholm

I would use the stronger half shafts regardless.

Earlier in this thread, there is a video of a stock-turbo stock-engine street Mustang Ecoboost running an 11.03 at 122 mph, on the stock axles.

If you can get a K/SA four-cylinder Mustang into the 10s, then yes, the rulebook will require you to run aftermarket axles. But until that point, I think that $2,000 would be better spent elsewhere, in my humble opinion.

[davidhuff]

Originally Posted by 6130

Earlier in this thread, there is a video of a stock-turbo stock-engine street Mustang Ecoboost running an 11.03 at 122 mph, on the stock axles.

If you can get a K/SA four-cylinder Mustang into the 10s, then yes, the rulebook will require you to run aftermarket axles. But until that point, I think that $2,000 would be better spent elsewhere, in my humble opinion.

Have you bought a Mustang Ecoboost yet or did you check on the one I posted for you on craigslist because you will not find one any cheaper?Just Saying.

[gumbalaya]

Originally Posted by ALMACK

Yep. I still have the e-mails.
1996 and newer with a 15 % reduction would be nice.

Doesn't seem like it will happen now so all the '96-'07 combos are stuck with what they are I suppose.
Just a hand full of the 1996-2007 production cars are running in Stock now so there are all those combos in the guide that will never be tried.

Too bad because there are so many really nice condition OBD II cars out there cheap

I never heard of this 15% rule before this thread, where is it published?

So would a MY2008 car get the 15% reduction? There's a certain Pontiac Solstice/Saturn Sky combo that Billy Nees likes a lot that the rule may apply to.

They did make a few Pontiacs & Saturns in 2009, but they're not in the Guide. If they were to be added to the Guide, would they get that 15% reduction?

Pontiac made a G8 GXP with a 400HP LS3 & a stick in 2009 that's not in the guide, which would be pretty cool also!

[ALMACK]

Originally Posted by gumbalaya

I never heard of this 15% rule before this thread, where is it published?

So would a MY2008 car get the 15% reduction? There's a certain Pontiac Solstice/Saturn Sky combo that Billy Nees likes a lot that the rule may apply to.

They did make a few Pontiacs & Saturns in 2009, but they're not in the Guide. If they were to be added to the Guide, would they get that 15% reduction?

Pontiac made a G8 GXP with a 400HP LS3 & a stick in 2009 that's not in the guide, which would be pretty cool also!

Kyle;

The 15 % reduction on combos already listed in the guides never went into effect.

Jesse tried. He had a meeting with NHRA but Glendora did not go for the idea of re-factoring existing 1996 and later production line ( VIN )combos.

However, I do believe his meeting set the foundation for the current 85/85 deal for all new combos listing in the guide this year (and beyond)

[gumbalaya]

Thanks for the info!