This is NOT an advertisement for Banks products. However my first mod in the fall of 1999 was to get their Stinger package, and while sorting through some old stuff I came across their brochure that gives dyno data on their 99.5 test truck for their stuff compared to stock. I painstakingly transferred their dyno graphs onto my computer so I could compare them with my model. I decided to post this because I think it provides a quick way to estimate your dyno results by comparing your mods with those in the Banks packages, and see where you're likely to fall on their dyno graphs.

The second set of graphs compares the Banks dyno data with my model. Thanks to Pocket for pointing out the importance of considering fuel atomization, I added that to my model, and I'm now getting better agreement between measured and predicted MAF vs dyno results. I used to assume that black smoke meant that essentially 100% of the MAF was being combusted, and I calculated the fuel needed for that, and used the thermodynamic function I've developed to calculate how much fly wheel HP was produced by that amount of fuel.

Pocket pointed out that you can't combust 100% MAF with a stock HPOP because it loses too much pressure and leads to poor fuel atomization if you push the fuel setting too high in an attempt to combust all the air. In fact with too high a fuel setting you wind up with black smoke and less HP than with a more modest fuel setting that allows for good atomization.

In my comparison graphs I adjusted my volumetric efficiency function to best match the air flow quantity for the Power Pack, and my model outputs for HP and TQ match the Banks curve for the Power Pack very closely over the entire RPM range. I didn't go to the trouble of adjusting the air flow quantity on the model to match the other packages, I just turned down the fuel setting on the model by reducing the % MAF combusted from 90% MAF for the Power Pack down to 70% MAF for the stock case. As you can see, by just doing that much my model still matches the Banks curves fairly well over the RPM range that determines the maximum HP and TQ.

The Banks acceleration data appears to be slower than many drag times I've seen posted, and when I get time I'm going to do a detailed analysis of that. Acceleration and drag ET's depend mostly on the area under the HP vs RPM curve as you shift up through the gears, and that's a rather involved and time consuming analysis.

 

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Anyone out there with a banks kit ever make 660 lb-ft of torque?

 

Gene, am I missing something, or how does the "Git Kit" net you the results it says (Takes exhaust cfm from 600 to 939 @ 1psi) ORRRR does that mean in a comparison, the git kits exhaust can flow 939cfm with 1psi restriction, vs stock which can flow 600cfm at 1psi restriction? It makes it look like the motor makes that much more cfm at 1psi.

 

Ernest, I also wonder if they ever considered air temperatures, and humidity while testing the different kits. If you look at the Stock vs Git-Kit, with no changes to the induction system, it drops the air filter restriction? Then there is an obvious drop when they installed a K+N air filter, but then again, with no more changes to the induction side, they measure less and less air filter restriction as the kits progress. They do have an asterisk that says at equal flow conditions. So what gives?

 

I'm also wondering what my discovery of less (or no) air in the fuel supply after in-tank mods & CCK or reg-return affects this. Injectors ingesting aerated fuel HAS to affect the performance of them. The fact that I don't get my low HPOP pressure as easily is a testament to that, but goes right along with Pocket's suggestion I think.

EDIT: I CAN'T WAIT to get my truck on the rollers to see where I'm at.

 

In order to check your dyno results to see if you got a good run, you need to compare your maximum values of HP and TQ to see if they're internally self consistent, as one is mathematically determined from the other. If they're not self consistent, and the run was done on a portable inertial dyno vs a shop load dyno, then the TQ reading is probably lower than what it should be for self consistency with the HP reading. The HP reading might be ok, but not getting a self consistent set of HP and TQ readings on a given run casts doubt on the accuracy of that run.

The load type dyno allows steady state operation at a constant RPM and boost whereas the inertial type dyno is subject to transient errors as the operator revs the engine to accelerate the drums. Also, operators of the inertial type dyno often don't fully load the engine in the lower RPM range where the TQ is a maximum.

These graphs give plots of RWHP, along with the corresponding plots for RWTQ, and the summary table gives pairs of self consistent maximum RWHP and maximum RWT. As you can see from the graphs, in the RPM range for max HP and max TQ the plots are fairly flat, so for an actual dyno run determining the precise values for max HP and max TQ isn't exact like in my computer model. However, your max HP and TQ should be fairly close to these pairs if you got an accurate run.

If you study the table, you'll see that you can use your dyno readings and interpolate between the lines to see how self consistent they are. For example, look at the lines for IAT=80, 100, and 120, and you see that the HP for IAT=100 is half way between the HP for IAT=80 and 120, and likewise the TQ is also half way. So if you get HP and TQ numbers that don't exactly match the ones in the table, just see if they line up equally between the values that are given.

 

The Banks brochure has a part # 96691, and they might still be available at a Banks dealer like Camping World. On page 2 there's a bar graph comparing the exhaust flow between the Git-Kit and stock at 1 psi Exhaust Back Pressure, EBP. My interpretation of that graph is that you increase the throttle setting on the stock until you see 1 psi of EBP and you measure 600 CFM flow. If you do the same test with the Git-Kit you see 939 CFM at a 1 psi EBP, because the straight through muffler and larger tailpipe allow a higher CFM at the same EBP.

In the table they give different EBP for equal flow (2.1 psi stock vs 0.8 psi Git), but in the graph they give different flow (600 CFM vs 939 CFM) for equal EBP. All of those numbers look self consistent to me!

 

If you read the various tech articles on the Banks site, they claim to do a better job of calibrated dyno runs than anyone else. Also, all of their dyno results are exactly self consistent between their HP curves and their TQ curves, which is more than I can say for many other dyno results I've seen posted on this site!

If you check my post on turbo surge, I gave a discussion of how reducing EBP increases VE and therefore MAF for a given throttle setting. My interpretation of their air filter restriction data is that equal air flow means equal MAF which gives equal HP, and that reducing EBP allows you to achieve the same MAF and HP with a lower CFM through the filter, which produces less restriction. The lower CFM produces the same MAF and HP as before because the VE is increased due to the lower EBP.

 

I've previously posted about a test of the FASS at Browns Valley RV Performance, where before and after dyno runs showed that installing a FASS gave a 12 HP increase with a stock tune, and higher increases with the more aggressive tunes. Your mods probably got some of the air out, but if you check the post by Dennis on the subject, he has all the in-tank and other fuel mods, and still saw a big difference when he installed the FASS, or whatever version he sells. He also reported that Jody saw a similar improvement.

If you check the Racor site, they've done testing that clearly shows most of the air is dissolved in the fuel when you buy it, and a lot more gets in there from sloshing around, and the mods you've done so far don't get any of that air out! So if you see an improvement now, there's still more to be gained with a complete air removal system.