Highest HP for a 3rd Gen?

[MD500E]

I am about to order a new truck and would like to end up having about 500 to 550 rear wheel HP. I was just wondering what Is the highest hp that you guys have seen on the dyno? It looks like one of the new high hp boxes, a set of injectors and a turbo... . maybe twins, would do the trick!



Kevin

 

[qzilla]

I have seen over 6xx with Twins in NOV/02. MOre recently we have seen 6xx on a single!



It took drugs, but we made it!





Quad

 

[Vaughn MacKenzie]

Without drugs you can throw the biggest injectors and boxes at it you want, but beyond about DD2 injectors and a good fueling box the CP3 and fuel rail run out of capacity, and you reach a HP cap in the 500s.



The next major BOMB these trucks need for more power is someone to figure out how to modify the high pressure injection pump and the fuel rail. And to make the injection event quick enough because it seems for example with the TST box on higher settings fuel delivery terminates so late in the power stroke it just makes tons of heat and destroys turbos (and certainly is killer on the exhaust valves).



Vaughn

 

[ChrisKringle]

Heard 584 w/hx40, 675 on nos.

 

[Jim Fulmer]

625 without N2O... ... Canada based... ... anyone want to guess who built it



Jim

 

[PGoble]

507 rwhp with DD stuff.

 

[KLockliear]

We did 563 waaaay back with just the standard stuff and a set of hotter than normal injectors. When the new Edge box comes out, and the bigger single to support it... over 600 on #2 looks pretty easy.



How muck do you need?

 

[Agades]

OR



whats even more important



TORQUE



and at what RPM is it kickn in at



and is it a curve, a mountain or a plateau on the dyno chart



If you just want high HP to kick in at 2900 RPM , you can get a gasser to that



I bought a diesel to pull the arse off a chevy at low rpm

 

[thejeepdude]

Originally posted by KLockliear

We did 563 waaaay back with just the standard stuff and a set of hotter than normal injectors. When the new Edge box comes out, and the bigger single to support it... over 600 on #2 looks pretty easy.



How muck do you need?

I thought you were the one that said the CP3/fuel rail was the restriction once you get to the ~500's? Are you saying the new edge box will get around that somehow? Or are you saying you've figured out how to get past that bottleneck?

 

[qzilla]

We are not sure of the torque. The dynojet we ran on stops at 1200 ft lbs.

 

[Agades]

Originally posted by qzilla

We are not sure of the torque. The dynojet we ran on stops at 1200 ft lbs.

maxin out the dyno:-laf



can you post the chart?

 

[KLockliear]

I thought it was a fairly broad curve.



#ad




563 was the outer limits of what could be done with just rail pressure/injectors and the current turbo. More will be had with a larger turbo, the pulsewidth/timing boxes and perhaps more pusher pump.

 

[SRadke]

Kieth, am I reading that right to see the peak torque at 2400-2500 rpm? That seems late to me. Is it only the timing and/or pulse width boxes that will make a peak below 2000? That was using your current production Jammer turbo I assume? Thanks.



-Scott

 

[KLockliear]

Yes, you are. The timing/pulsewidth boxes will be able to change the curve much like the comp/ez did for the older trucks. Rail pressure was pretty linear. How much tq do you want down low anyway? More to make the bottom end move around? Slip the clutch, break the trans?



It's making almost 700ft-lbs at 2000rpm. That's 225ft-lbs over stock.

 

[SRadke]

I do my driving between 1700 and 2200 rpm. That's where I want my power. I understand it is up higher if I need it but it's nice to not have to go looking. Sometimes I don't have time to shift down before I imbarrass a ricer.



-Scott

 

[Greg Boardman-RIP]

Like Kieth said,



It is making 700 TQ at 2000 rpm,s. Ill take that any day.

Originally posted by SRadke

I do my driving between 1700 and 2200 rpm. That's where I want my power. I understand it is up higher if I need it but it's nice to not have to go looking. Sometimes I don't have time to shift down before I imbarrass a ricer.



-Scott

 

[SRadke]

Originally posted by KLockliear

How much tq do you want down low anyway? More to make the bottom end move around? Slip the clutch, break the trans?



It's making almost 700ft-lbs at 2000rpm. That's 225ft-lbs over stock.

How is 1000 ft/lbs at 1800 rpm any harder on the clutch and trans then 1000 ft/lbs at 2200 rpm? Torque is torque. I just expected to see it a little sooner with this Jammer turbo that is suppose to be a fast spooler. I see that as another problem with the pressure boxes, they leave you at the mercy of the original DC/Cummins program that doesn't fuel early. JMHO.



-Scott

 

[thejeepdude]

Originally posted by SRadke

How is 1000 ft/lbs at 2200 rpm any harder on the clutch and trans then 1000 ft/lbs at 1800 rpm?

Actually, I think he's saying 1000lbft is harder on the transmission at 1800RPM than 2200RPM. This is true. If you had 1000lbft at 1000RPM you'd be a whole lot more likely to slip the clutch. Think of it this way...



An analogy: take a theoretical vehicle with a completely flat torque curve... say, 400ftlb flat from 500-5000 RPM. It would be a lot easier to peel out from a dead stop than 5mph. And it would be easier to burn rubber at 5mph than 20mph. All cases are in 1st gear and the motor is making the same torque. However, the differece in potential energy vs. kinetic energy makes it unlikely that the 20mph throttle stomp will create any wheelspin at all with 400lbft unless the hypothetical vehicle is very light. The tires on the pavement are nothing more than a friction surface, just like the clutch in a manual or the clutch pack in an auto. Plus, with an auto you have the added problem of less line pressure at lower RPM, thus making the high torque at low RPM even more likely to break things.



All that said, I STILL want as much torque as possible at as low RPM as possible. I would rather let my right foot and my own judgement determine how much torque I need at the moment. If I break something, I'll just make it beefier!

 

[SRadke]

Originally posted by thejeepdude

Actually, I think he's saying 1000lbft is harder on the transmission at 1800RPM than 2200RPM

Sorry you're right, I worded it backwards. I don't think your analogy works though. It takes a certain amount of torque to slip the clutch, or break the tires loose. There is a certain amount of torque required to break the tires loose and with any number above that they will slip. The torque (unlike hp) is multiplied through the transmission and rear end. With your analogy (in first gear) you have about a 4:1 (wild guess) reduction through the trans and a 3. 73:1 reduction through the rear end. Your 400 ft/lbs has now turned into 5970 ft/lbs at the tires. It doesn't matter what rpm your motor or tires are turning. If that is enough torque to make them slip they will.



That is a tough analogy because of the multipliers. Moral of the story is torque is independant of rpm. It doesn't matter how fast your clutch is spinning when you try to put more than X torque through it it will slip. Potential and kinetic energy have no place in the formula unless you want to take into account the torsion action of the driveline and axles in the wheel spin situation but we're just talking about the clutch and trans here. Sorry to the rest of you for getting off topic.



-Scott

 

[banshee]

Scott,



A clutch will generally hold a little more as RPMs increase to the centripital acceleration (and thus force) of the fingers on the pressure plate. Some of the clutch manufacturers take advantage of this by placing weights on the pressure plate to apply even more force as the engine speeds increase. Centerforce's Dual Friction had these, and their motto was "The higher you rev the harder we hold". But in general, you're right, 1000 ft/lbs is 1000 ft/lbs and will break or slip something regardless of the RPM.