Classic 1969 Mercury Cougar Restomod
 

Hi from Southern CA

I own a 1969 Mercury Cougar
that has been heavily modified.

It's now got a 351w overbored 0.03 so 357w.. Afr 205 aluminum heads a decent cam, aluminum intake, forged internals, internally balanced. An EFI Holley Sniper An Aod has been added

It's rated over 500hp..
Not exactly eco friendly.

BUT a lot has been done with efficiency in mind...

I first recorded my tank to tank mpg at 9.. the latest modifications have brought it to ave 14..

I also have a 2005 Civic so not shooting for moon as it has a few eco upgrades already and the Civic a daily driver... doing ok.

I'd like to shoot for 20mpg + on the Cougar which I think is doable while keep it close to looking original.

I'll list everything done later as well as projects.

Belly pan next on list.
Raise thermostat to modern 195 degrees.

Welcome.

Is it as convertible XR-7? [probably not?]

The bellypan could start with sealing up the radiator bulkhead.

Welcome!

I should mention I'm thinking engine Bellypan sealing up about 3/4 of it. I ll likely vent the hood near the radiator to extract heat amd get just a tad of downforce too by doing so.

I mention the bulkhead to insure all the air is available to the radiator. If there is sufficient room ahead of the radiator behind the grillework a bellmouth helps more.

Might be achievable, but it will definitely involve some adjustments to the car and maybe to your driving style too. I guess it might be quite tempting to make the V8 roar loud once in a while...

So goal's already been achieved... new goal =25mpg

So the big change that made it possible was regearing the rear differential.
I was still with the original 2.75 rear end ratio.

I had somebody who mentioned to me in another group that this ratio was killing me. I'd say about 90% of the info out there just says that lower #'s equal better gas mileage. This poster had mentioned to me , nope it's making your engine lug.. It has to really work to get to your RPM and it's way below where your engine's rpm efficiency curve.

Well he is right. I had spent $1000 getting my rear end differential. The best bang for your buck upgrade and they aren't kidding. It will pay for itself though in gas mileage saving in only a few months.

I've got an approx 27% increase in torque with this new rearend. It's a definite jump in power. But I've also got a huge jump in gas mileage as my previous best was 14mpg and now I'm getting almost 22.. (and this is two fillups so not a fluke)

So I've got a 500hp 69 Cougar that's been lightened a bit, has an AOD, new rear end and Sniper now getting much closer to modern day fast cars.

now to lighten it a bit more. and more tuning the EFI Sniper.

What differential ratio are you using now?

3.5 now.

I had debated between 3.73 / 3.5