4000 RPMS on the Dyno

[jwilliams3]

Bottom line, if the chart is accurate, at 2000 rpm the truck does not make enough power to hold 55 mph, much less keep the engine running.

#ad




I guess mine wont run at 55mph either..... :-laf



Thanks for sharing your expert opinion though!!

 

[Bob Wagner]

John, Is correct this dyno was only to prove full fueling to 4000 rpm



This was the first dyno just to put the competition is place. So many say that they can fuel to 4000 RPM but its bs because no one can back it up with a dyno graph.



Thanks for your support

 

[BSwope]

This is AWESOME!!!!!!!!!!!!!!!Oo. Oo.

Great job fellas!!

Time for me to start puttin some more jing back!!

 

[TCluff]

sounds like someone needs to pm me on where and when and how much...

 

[Tomeygun]

Tho, there's that one thing that is an unknown, how well will the syncro's like 4000rpm?

hehehe, no synchos needed when you have a 42k sled behind you and you are inching out the DD in 4th gear and the ol' cummins is spinnin' at 4k :-laf:-laf



woo-hoo!!!!!!!!!!!! Justin - Make us 3rd gen guys proud!!!!!

 

[AEzzo]

That curve begs a lot of questions for me. The first is, how come there is no power below 2150 rpm? Don't most of our trucks put out a bunch of torque down below 1600? What kind of gearing do you have that gives 57mph at 2200 rpm? Also, how did you get the valve float to stop above 3500rpm

I'm no expert but I've been on the dyno a couple of times. The dyno runs on my truck were started in OD in lockup at 55-60 MPH at about 1800 rpm and then the dyno was loaded and the pedal put to the floor. I believe that lower rpm readings will be off due to low boost levels compared to normal driving.

As to the question about rpm to speed being off, I've read that the run was done in third to limit over all MPH on the dyno. He was not to exceed 120 MPH.



Hope this helps.

 

[JasonCzerak]

55mph with 4000# rollers NOT EQUAL 55mph + 7000# truck + wind resistance.



It's simple math folks. Stop freaking out.



I read some place that the new 6. 7 CTD has more HP and TQ AT IDLE!!! then the 89 CTD had at peek. Why is 100hp, essentially while freewheeling so hard to understand?

 

[Bean]

Also this was not a normal street truck, built trucks usually do not make tons of low end hp and tqu due to slower spooling larger turbos, this will show up on a dyno even more then on the street. Mine on a dyno will not make power before about 2800rpms, I mean dead. On the street I can run it just fine but it is laggy.



That graph makes me tingly in my special parts.

 

[MickeyMiller]

WOW!... ... . got to get to 10 characters...

 

[JCasper]

FYI,



The truck that ran on the dyno is VERY FAR from stock. From what I understand, Yes valve springs are a necessity.

 

[SNiebaum]

FYI,



The truck that ran on the dyno is VERY FAR from stock. From what I understand, Yes valve springs are a necessity.

Rips truck is certainly far from stock... it's flat out built for hauling the mail and runnin' the 1320'... .



People have been clamoring for fueled RPM's, now they can get them but as with anything, it's going to cost them some pennies... in this case an upgrade to their valvetrain to handle it... .

 

[Bob Wagner]

We will be dynoing a mildly bombed early 2004 very soon

 

[Tomeygun]

We will be dynoing a mildly bombed early 2004 very soon

darn... And I thougt the post over at NWbombers meant you are looking for someone near "ofallon, MO" :-laf:-laf



You know, that sounds alot like "southend", hahahahaha

 

[Bob Wagner]

tomey you have mail :-laf

 

[DPeltonen]

#ad




I guess mine wont run at 55mph either..... :-laf



Thanks for sharing your expert opinion though!!

ouch! Wish I was the expert. Maybe I should practice asking for info in a different way. Unfortunately all I was provided was the graph... and I can read a graph. No info on the truck in the run or the graph... I had to ask. As far as a diesel that can run 4000 rpm... no problem. With some valve train mods and a pump that can keep up, it is possible. Volvo has been playing with high rpm diesels for years (over 15).



I would like to see and hear more about this engine. Given that the numbers are real (no reason not to believe they are not), I could get a real education on performance enhancing.



Oh, and jwilliams, your printout shows over 100 hp and 300 lb/ft tq at 1900 rpm, while Bob's chart indicated he would have 0hp and 0tq at 2100 rpm (or 55 mph). Not an expert opinion, just an accurate read of the facts presented. Since absolutely nothing was given regarding the engine, any modifications, or how the set up was done for the dyno, I responded based on the information given. In fact, there is still no information presented on how the RPM was verified. Actually there is still no information at all, just a big whoopee and a lot of replies that say congratulations. All I can do is assume that there is much more than presented. And we all know what they say about assume.



As far as reading and interpolating graphs, I have been doing it as a part of my job for 34 years. I do find it interesting, however, that with all the questions I raised, none were even addressed other than one comparison that was the equivalent of comparing an apple and a rock...

 

[betterthanstock]

ouch! Wish I was the expert. Maybe I should practice asking for info in a different way.

Actually, don't feel too bad. Jwilliams3 truck is a wuss below 2500 rpm. What his has at 2500 (torque), mine has at 1600 rpm. Of course, after 2600, mine tapers off, and his climbs thru the roof. But on the road, he needs to scream to keep up with traffic, while I upshift at 1800-2000 rpm. Even towing about 12K, I was able to outdrag a school bus while upshifting at about 2100. To each his own, but if you can afford a quarter mile truck only, go play. Now, an engine that would have my low end, and his high end, or better yet 4000 rpm, that would have my respect! I think that may require twins, or triples, and variable cam timing.