When my Hemi was new i could pin it from a stop and it would spin and the stuff on the dash would fly off....now when i pin it from a standstill or even break rev it to 2400 before i let go just before i start burning out it still doesnt take off fast what the EFF is going on??? i mean it screems up top and in the mid but the bottom take off it all gone wont spin for the life of me on pavement from a stand still any ideas???

 

How many miles you have on your truck?

 

32,311 miles lol its almost new still and the motor is GREAT idles niiiicceee and smooth and uses no oil what so ever.

 

First thing that comes to mind is that it is time for your 30,000 mile tune up.

 

New tires or stock tires? What tune do you have loaded on your cortex?

 

same size as stock tires and am running the 87 octane tune. whats involved other than spark plugs in the tune up??

 

The oil was just replaced the diffs are fine for another 5 thousand or so until they are due i will change the spark plugs myself the air filter is perfect what else??? tranny flush?

 

run on 89 and you will get the engine running to full potential unless you have a 91 or 93 tune.

 

dont got 89 octane fuel...either 87 or 91 and im not running 91 it has always ran fine on 87 until now 91 costs to much specially when i fuel up 3 times a week at 90 bucks

 

Guys that have run 87oct have had piston ringland issues from detonationbecause the way they are constructed. Chrysler recommends 89 in their tune for the Hemi's. If the 87 tune on the Cortex takes away timing(prob does), then you will obviously see a loss in performance. The Manufacturer should not recommend but require 89oct IMO. I always ran 91oct and never had any issue's. So the 87oct mixed with worn plugs and a different compound tire can effect spinning and take-off. Stock tires are fairly slick and spin easy.


Your that worried about fuel prices and you own a truck?? Let's say 87oct costs $2.69 and 91 costs $2.85. When filling up with 24gallons bcause you prob have a 26gal. tank. It costs you $3.80 extra to have the performance your looking for. But it's your truck and you spent $300 on a Cortex why? To save gas? That's the only reason to install and run the 87oct tune. You cannot have gas saving mode on and expect tip top Dyno numbers.


3x's a week of 24gal's at $2.69 is $193 per week in gas and $775 a month just for fuel.
If you fill up 3 times a week, then you would be better off buying a car with a 4cyl that gets good gas mileage. If you spend $10,000 for a car. Your monthly payment would be between $200-$230 for a 60month loan with zero down. Now 3x's a week in the Ram is about 300miles per tank. Total of 1,000 per week. Most 4cyl gets 30mpg. 33.3gallons in a 4cyl to go 1,000miles compared to your truck that uses 72gallons.

At $2.69gal x 33.3gal= $89.57 per week and $360 per month plus $230 for car payment comes out to $590total for car payment and gas. Now add another $60 for insurance. $650 to own a car.
There you got it. It's cheaper to own and insure a $10,000 car and still keep your truck and the mileage down. It's CHEAPER and you will OWN the car. i dunno 'bout you, but I went this route myself. Now I've had my '08 for 16months now and only have 6,000miles. Meanwhile, my beater car is already been paid for and owned AND i have saved money while doing so. Now if gas is more expensive where you are, then figure that you'll save evn MORE than what i am showing! Figure for every .10cents on the gallon more, you'll save .30 more cents per gallon for owning a car.