You won't see more than 40 if the wastegate is set at 40? I don't think you will make more than 520 hp if you don't have more boost out of your turbo than that...run that sucker up to 50.

Boost is tooooooooooooo low...wastegate is open...power is gone in the smoke!

 

I here what your saying.. But your missing the point.. I have a wastegate controller in between the turbo outlet and the wastegate canister.. In its current configuration it CAN'T open before 50 psi because the solenoid won't let it.

I have a boost gauge on that line to see how much pressure is there, and it only registers pressure when its getting past the solenoid.. There was absolutely no pressure getting to the wastegate from the solenoid.

Unless the wastegate can get pushed open from drive pressure alone.. Can it? I wouldn't think my DP would be that high anyways with the 71 wheel....

I thought it was the wastegate controller malfunctioning so I clamped it off and it still didn't seem to boost anymore than that..

Again, on my way home from the shop I hit 50+psi 5 times.

Chad

 

I would say it has to be a load issue.

 

Your description of the way it was run pretty much nails it for me. We run in OD. Run the truck up through OD to about 60-64mph, engage the load (you can run it all the way up with the load if you want) let it bog to 55 or so (should be at 10-15psi of boost) and then start the run and go to the floor. Make sure the speed limiter off on the Smarty. I bet that helps, give it a try

 

what rpm are you seeing at 80mph?

 

Do you have a lock up controller....if not you the TC doesn't usually want to lock till 48mph...then when you run up to 80..its over in a second...I find running a cummins with a 48re...od is almost manditory....although they all want to run it on 1 to 1 which is 3rd.... I could get 90psi on the track and my highest on the dyno was 37psi due to tire slippage. If they could load it with the trailer and get over 50psi then dyno it adding a progressive load if possible...similar to hitting a hill...that should load it up till it hurts. KS

 

I am seeing 80mph at about 3100-3200 rpm I believe...

I have a BD Towloc on it, set to lockup at 40mph, and it does lockup, and stays there.

I like the idea of dynoin in o/d... It makes sense and a lot of people do it that way. This particular shop likes to do it in 3rd (1 to 1) and thats what I always believed was more accurate .. Of course thats coming from a gasser background of dynoing.

So should I try it again and do it in OD instead? I know it will build alot better boost doing it that way. Just seems like doing it that way your not getting a true reading. But thats where my knowledge on the subject is lacking.

Thanks guys! I appreciate all the help I can get. I'm going to sell my truck and my use this one, and then my wife will just drive her Liberty CRD around since it gets better mileage.

This is the truck I am going to be keeping (the 2005 with single pump and flux 2's) because I use it tow with ALOT.

 

Seems to me the street will "load" your engine more than a dyno will, especially if you are doing 3rd gear pulls. Turbo's need load to reach full potential and some of these dyno don't really cut it when it comes to these big diesel rigs

 

Ok well I think I'll retry it in o/d instead. That will at least let me get it spooled up a little better.

Going in 3rd its over in a flash. I mean it goes from 1800 rpms to 3200 in a flash. I kind of wondered how it would build alot of boost if you are starting out from 1800 and nailing it.

Trefling, do you dyno your truck in O/D or 1:1?

 

i dynoed 528 horse, 1082 lbs on a dyno with 30% load with my sps62/14... i let the truck go into overdrive then got rpms around 2000 and floored it... stock cp3, stock stixs, and stock fuel system, and revo tnt on 9

 

What kind of dyno were you on?

 

dyno jet i belive

 

Don't worry about the boost, get on a Dynojet 248 and see where its at. I've seen the mustangs 20% low.

 

After you get the converter to lock you can then slow down some before the pull begins. You just have to keep it to the point where it won't down shift to 2nd when you mash it.

Some trucks like 4th better. Most trucks can be dynoed in 3rd. I tried one run in 4th on my truck and it didn't make any difference.

 

Or the dynojets are 20% high.

Load dynos usually tell the truth a little better than inertia dynos. Just ask the dragstrip.