Hey guys. So the other night I went out to a closed road I've been on several times. Ususally I have no problemn burrying the speedo past 200km/h (canadian truck) I seem the be lacking almost all top end in third gear. I couldn't break 165. Any ideas what might cause this? 2 months ago we had it up to 235 on my friends (local Sheriff) radar gun.

Any help is appreciated (and those going to bash me for going that fast need not respond)

 

At least you stayed safe. Any number of things could be wrong, Spark, fuel delivery, air, etc... What is 235km in mph?

 

235Km/h is about 146mph. And last time I checked, even with a SC'ed truck, the top out is 140.

 

Superchips has a 140mph speed limiter, unless the newer one can up it a little more. I know the Diablo ups it to 190mph

 

stock suspension & 140+mph = scary


going that fast could be a number of things....Air density, altitude, wind speed...etc

 

I didnt know the DSP ups it to 190. Now THAT is scary

 

I was running a borrowed diablo at that point and the top speed was 150. Truck seems to run out of power around there anyways. The sc constantly pulls 140 normally for me on the same stretch of road in similar conditions.

There doesn't seem to be any signs of lack of power at any other time tho so I'm somewhat boggled...

Truck is due for a tune up but would it cause such a loss of power?

 

I think its more for bragging than anything... "Oh yours can only do 140? HAHA Mine can do 190!"....

 

how long does it take to get that beast up to 140? i did a speed run in mine and got up to about 105 but it didnt seem to be pulling much harder and was vibrating so i let off. this was with od off and 91 sc tune with speed limiter maxed out. maybe i just didnt hole it long enough??

 

Lotsa things can affect that: wind direction/speed, humidity (drier air has more oxygen and a bit more power), tire inflation. The list is long. Heck, a pickup truck isn't exactly aerodynamically efficient anyway.

I recently had to lean on mine -- according to the GPS, it got to 109.3 with "plenty of pedal left". I've seen an indicated 115.