It should be making at least a 100 horsepower more than what it put down.

Seeing a data log or the tune itself would help but that isn't really something that is possible right now.

 

my tuner and I don’t actually believe that dyno graph. We believe the dyno tech didn’t lock the converter up, which makes sense. Come on now, a 2005 GMC Yukon Denali with a whipple 2.3 w/3.00” pulley making only 250 rwhp 🤣🤣🤣 that’s laughable. Just a waste of money and time for me going down there. According to the rwhp online calculator it takes over 390 rwhp to launch a 5820 lbs suv to 14.3 @ 97 mph. My truck runs like a r*ped ape and the tune is spot on so no worries there

 

before I do anymore mods, my tuner wants me to beef up my fuel system which is understandable but I’m not trying to put that much into the truck to begin with. Just more parts I’ll have to remove if I decide to sell. I want to add a NW 102, 2/3 bar map sensor or LPF 100 mm maf, and a smaller pulley. My tuner wants me to add dual pumps and injectors and he’ll tune me SD. I’m still contemplating all of it

 

you are a confusing man


But yeah that dyno is screwed up. You are pretty close to 400 hp with that set up and ET

 

Your tuner is right about needing more fuel. You need to get the 2 bar map, and add a bigger fuel pump. If you don't want to do a custom dual pump, deatschwerks makes a drop in unit that is good to about 800 HP. Keeps factory fuel gauge working and works with factory wiring. (works better with a hotwire kit, but does work on factory wiring.) Hell, it can even run on the stock lines if you have a return style system.

But based on the weight and the times you are showing, I think the truck is close to correct. Could it do a little more, yeah probably. but you aren't gonna gain a half second with some major thing you are missing or something. The 2 bar map will let you log boost even if you don't have a gauge and you will know how much you are making. That will be a big help on determining power. You can try out the boost calculator excel sheet that I attached here. Its pretty close if you enter the information correctly. I put in some guesses and added the info you told us. 2.3 whipple, with a 3" pulley. I assumed a stock truck balancer. It shows you should be running 8 to 10 pounds. That 6.0 made 335 HP stock at the crank. assuming 15psi would double HP, which is pretty close, then each PSI of boost is worth 22.33 HP. So you gain 178.66 HP to get a total crank HP of 513.66. Run that through a calculator and you get a 13.5 at 105 mph. Which is damn near nuts on because thats what my srt10 did with near identical numbers.

Given that you are running a 14.3 I am going to guess that you are making less boost than you think. Blowers are very sensitive to pre-rotor restrictions. Look at your intake tract and see if something could be a restriction. What filter are you running, what maf? stock air box? Then take a look at your exhaust. If there is a restriction there then it will mess with your HP gain per pound of boost. Also check your IAT's, if its too high the truck will pull timing and kill power to prevent damage. Increased restrictions will also increase IAT which could mean a combination of all three is effecting your truck. It is behaving like it is making about 5 PSI of boost instead of 10. All stock components surrounding your blower may be killing the gains you should be getting. Take a look at the screenshot below, and get a way to check your boost numbers. See what it should be making and how accurate that is to what the truck is doing. Then look for some well known causes as to why its not doing what you think it should.




Forgot to add that I did not create this calc sheet, another member on here did who's name I don't remember now.

 

you’d be confused too if you drove 3 hours one way for a dyno session and the tech it telling you your truck only makes half of what you know it makes and you’ve been mopping up sports cars stoplight to stoplight back in town

 

im working on the bigger pump. It’s been trial and error with my fuel pump situation because I didn’t do my research and it’s costs me unnecessary funds but I do have an Aeromotive 340 sitting in the garage waiting to be installed into my oem module and I’m gonna try and replace the filter but hopefully I don’t ruin my module, I couldn’t find any videos to help with the filter part.

I’ve been eyeballing that deatwerks unit for awhile now but it doesn’t come with the fpr built into the module so to me that’s not plug and play. I’d have to run lines and get an adjustable fpr. I know that’s what I need, but I’m trying to see if I could do it without it first. Definitely gonna get a boost gauge. I’m starting to see how much of a necessity that is now.

 

Yeah, I bought the kit with lines and the regulator and just put it all in. but if you have the trucks with the fuel pump control module, it can run that pump and control the fuel pressure. Deatschwerks doesn't recommend it, but it will do it. The boost referenced regulator is better though.

 

im not too sure if my vehicle has a fpcm or not. I’ve always assumed that it didn’t but I could be wrong. I’m also assuming that the kenne bell bap is doing its job. I’ve verified and it’s putting a steady 17 volts. I’m gonna leave it connected whenever I install the aeromotive 340.

injector swap is my next issue. I want to change them but it looks like I may have to remove the headunit and I’m not too thrilled about that, so I’ve got to wrap my head around that idea as well. That sucker was heavy and cumbersome and I don’t like the idea of moving it once it’s already been installed

 

I missed that you had the boost a pump. That and the 340 will get it just fine. if your supercharger is anything like mine (working with the LSA) then you will probably have to pull it. My injectors and coils were so close together I had to modify the coil brackets to drop them a half inch further down the valve cover just to be able to plug everything in. Even though it may be hard, doing it right is better than not doing it.