What is the easiest and cheapest way to increase high end torque?

 

I don't know about easy or cheap but a cam with the proper grind could move your power band into the upper RPM's. Just out of curosity why would you want more upper end torque, in a big truck, especially 4x4 most people want better low end.

 

"High end torque" [&:] There is no such thing You can move the peak up further in the RPM band, but there's no way to create "high end torque". Unless you have a V10 or Diesel, your torque will always peak closer to the low end....where as the torque band on the diesel and V10 are fairly flat throughout the whole RPM range.

I agree that a cam is the easiest way to move the peak in the RPM range.

 

cutting the runners on the intake plenum or going with an M1 intake manifold would give somewhat of the result your looking for.. rom is right there really isnt something called high end tourqe.. better explained as the infamous "powerband" this is where the engine performs the most effecient and makes most of its power..

kinda like when someone dynos there truck or car,, and say you come out with 400 HP (hypothetical) this doesnt mean at idle your motor is producing 400HP.. its in the higher rpm's that these power is made at..

what your looking for my friend is just more HP.. low end tourqe on the other hand is something very true and its what gets you off the line quicker.. low end tourqe is also contributed to better mpg.. and better towing capabilities..

 

Exactly shot--- Torque gets you going, horsepower keeps ya going...to improve on top end, you must improve horsepower!

Good advice!

 

uh, I disagree on this... there is a thing as high end torque... it's keeping your torque curve as flat as possible. most dyno sheets show the torque dropping off the higher in rpm's you go. however some engine mfgrs (bmw) have been able to get the torque curve flatter throughout the rpm range. the flatter the better. I'll see if I can dig up an example when I get to work. (5am, time for the gym... later)

 

OK, looking back at the dyno sheets for my 325is, with all the mods I did to it, HP went up 8.1% and tq 11.3% (max gain). the peak torque before the mods was at approx 3500 rpms and remainded fairly flat until about 4900, then it started to drop off. after the mods the peak was shifted to the 4900 mark... at 3500 it was still climbing and became flat at about 4200 thru 4700 where it took off again.

stock tq @ 6000 rpms was ~= 147~148 (tough to tell on the graph)
modded tq @ 6000 rpms was ~162 (also tough to tell)

interesting though is @ about 6200 tq for both modded & un-modded starts to drop off significantly, hp flattens out a bit.

anyway's food for thought.

 

i see what steve is saying here.. you want to try and reduce the drop of TQ when you pass the opitmum rpm range for production... so moving the rpm band up or down would cause this to shift the peak curve of TQ.. but how could/would you bolt on a "flatter" tq profile?

 

Or you could get a Vtec, look at the torque!

 

well yea.. thats what steve is talking about. what the hell is a vtech?