also...can an open loop tune slow the car down in the 1/4mi?
last year my car ran a best of 11.1@123mph. this year i added the fast 90mm intake and a new cam. i gained 24 peek hp and tq and in some spots under 5,000rpm's i gained 33hp. this year the car only ran a best of 11.28@122 in the 1/4mi,this year the car is on an open loop tune. for racing what tune is better open loop or standard tune?
thanks, mike c.

 

WOT is open loop no matter what. You probably need to tweak your PE or OLFA tables to make the most of your new mods

 

a full open loop tune is where no O2 feedback is used...this sometimes is done if you have a cam with large overlap. Some self tuners do it just to have full control over everything thats going on rather then have a ton of sensors trying to make decisions.

 

so an open loop tune would not slow a car down in the 1/4 mi?

 

done correctly, no

 

what do you mean done correctly? like i said i gained power at all rpm's,but still made np gain in the 1/4mi in e.t or mph.

 

gaining power on the dyno in 1 gear is different then going to the track running through 3 or 4 gears with different conditions from one day to the next. Maybe a head wind that second day who knows...real world is different then a dyno.

 

yeah i know,but ganining power i should of gained e.t. i just thought i would look into this new open loop tune that my tuner put into my car to see if that may cause something.
thanks.

 

meaning if you are commanding the optimum AFR and Timing for max TQ/HP, you won't loose a thing. If your fueling or timeing is not optimal for you combo you will loose power.

 

Not exactly.Just because it dyno's more doesn't mean it will run faster at the track.We see it all the time. Your car is probly tuned for the most hp on the dyno but when you go to a real street/load condition the car is actually making less.

 

Its possibly running lean at the track - when it was spot on when on the dyno.
The tune might need to be shifted just 0.3afr points richer.

More power will make it quicker at the track in good weather.

My baby cammed car is tuned in open loop using EFIlives custom operating system.
It has done 11.619/116 mph 1.583 off just a 3600 stall and 3.73s at a race weight with me in it of 3625lb

Its also getting 30mpg at 70mph cruise.