Induction Overhaul FAQ

GENERAL

• Q: What is “Induction Overhaul”?
• A: The process of identifying and removing damaging restriction from the intake tract. This will identify the key sources of LLY load induced overheating.
• Q: Why should I care?
• A: Excess restriction, especially before the turbocharger compressor, is responsible for a number of heat related performance defficiencies. In other words, the turbo becomes more parasitic to the powerplant, creating more heat and increasing turbo shaft workload while consuming additional fuel to support these inefficiencies.
• Q: Who is affected?
• A: Every Duramax production vehicle manufactured for the model year 2004.5 and 2005. This includes medium duty Kodiak and Topkick trucks.
• Q: How was this flaw discovered?
• A: Indirectly, it was a search for LLY overheating cause that led to this development. COT, the turbocharger’s Compressor Output Temperature, was observed to be warmer than that predicted by formulas. This disparity led to a search for the source/cause of this additional induction heat. Eventually, the trail led to pre-compressor plumbing restriction, made worse by a method of boost control implemented in the new VGT.
• Q: What exactly suffers with this restriction?
• A: Fundamentally, it increases turbocharger pressure ratio without increasing boost. This means reduced turbocharger efficiency, turbocharger overspeed, while at the same time reducing air flow, increasing EGT, reduced economy, induces dangerous compressor stall (bark), increased oil and coolant temperatures, and very importantly, causes excess induction heat that contributes to performance erosion, and load induced cooling system overheating.
• Q: Are you saying that the widely documented, controversial LLY overheat issues are primarily a result of a mechanism that has NOTHING to do with the cooling system!
• A: Yes. The cooling system in the LLY works exactly as its predecessor.
• Q: How can a turbocharger plumbing restriction, of all things, possibly lead to an overheat of my cooling system? That doesn’t make sense to me.
• A: In the simplest explanation, the intake tract restriction causes the turbo to work harder, and make significantly more heat than necessary. That additional heat is carried to the CAC (intercooler), where the increased heat is rejected directly onto the radiator. Some of this extra heat passes through the CAC to combustion, hotter, rarified combustion air, reducing power output. To get a better and more detailed explanation, requires a complete understanding of forced induction thermodynamics, the mouthpiece restriction, and Thermal Feedback.
• Q: What is a “Mouthpiece”?
• A: The duct that connects to the turbo compressor.  In 2006, I didn’t have a name for it so that is what I called it since it connected to the mouth or face of the compressor. It is one of 2 main hardware components of the Thermal Feedback study.
• Q: What is the other?
• A: The Turbo itself.
• Q: How can I learn more about Thermal Feedback?
• A: Read these articles:
• Thermal Feedback Simple
• LLY Induction Overheating
• Thermal Feedback Primer
• Q: Who benefits the most by heeding these recommendations?
• A: Anyone who seeks to maximize high load performance in any turbocharged/supercharged vehicle. The more air you use (boost and rpm), the bigger your benefit. The biggest benefit goes to the user who tows constant heavy loads, using stock or high boost tunes, at high elevations. Anyone wanting to optimize the VGT for performance in adverse conditions will benefit as well.
• Q: Why does elevation seem to make my issues worse?
• A: To the compressor, elevation and restriction are identical. There is no difference, each makes air thinner. The compressor works best with the full 14.7 psia atmospheric pressure at sea level. Elevation reduces this ambient pressure, also reducing the pressure seen at the “mouth” of the compressor; this is exactly what a restriction does also. There is not much you can do about the pressure lost to elevation, but you can eliminate the manmade plumbing loss. If you remove 3 psi worth of restriction, this is no different than a 6500 ft elevation reduction. IOW, after the change, the truck at 6500 ft will perform like the unimproved stock truck did at sea level. This is a fact.
• Q: I’ve heard that if I do this, I need to reflash my PCM…something about MAF voltage scaling and OBD codes, etc. What gives?
• A: Untrue. MAF voltage scaling errors can, and do cause codes. However, none of the IOH kits requires you to reflash anything, because the MAF flow area remains unchanged. In addition, all kits are guaranteed code-free.
• Q: How does this mod compare to changing my LLY intake or replacing my exhaust?
• A: No comparison at all. This will be the most change you will see from a minor hardware change alone. This sentiment has been unanimous among adopters, hundreds of them.
• Q: Will this reduce the amount of fan-on time I experience in the summer?
• A: Yes, particularly while towing. If you noted that the fan didn’t seem to effectively control ECT on your tow trips, you will see that change for the better also.
• Q: Doesn’t my XYZ Intake fix this issue?
• A: No. Not one of the aftermarket companies have caught this. These benefits are apart from those benefits to dampen Intake Air Temperature rise. IAT rise does harm vehicle performance, and a True Cold Air Intake helps to negate that performance impact. The combination of an IOH kit and an effective True CAI remains the most effective hardware deterrent of Thermal Feedback, and performance erosion. Don’t assume your XYZ intake helps protect IAT rise. This assumption is usually incorrect. 

 

LIGHT DUTY TRUCKS

• Q: Will the Induction Overhaul Kit fit my 01-04 LB7 Duramax?
• A: No. It is specifically designed for the LLY, all 04.5-05 Duramax trucks. It has the worst restriction related issues of all the trucks, and hence the worst performance potential and highest induction heat liability.
• Q: Can I use the LLY IOH kit with my aftermarket intake?
• A: If your intake utilizes the stock intake tube, then yes. Otherwise, you can use the AIOH kit that is made for universal application to all aftermarket intakes.
• Q: I don’t want to give up my “xyz” aftermarket intake that I already purchased. What can I do?
• A: You have 3 popular options, in reverse order of effectiveness,
• 1. Return to the higher efficiency stock filtration, and use the IOH kit (recommended) or
• 2. Order the A-IOH kit (“A” for aftermarket), or
• 3. Order the recycled Machined LLY Mouthpiece (cheapest option)
• Q: Does the IOH kit have a machined LLY inlet mouthpiece, or is it completely different?
• A: Different. There is about 80% more flow area, and dramatically restored flow characteristics.
• Q: How effective is the cheaper recycled Machined LLY Mouthpiece, compared to the other options?
• A: It has about 50% of the benefit, but very inexpensive. A good value.
• Q: I tow a 13,000 lb toyhauler and tend to overheat. Will the recycled LLY MP help?
• A: Yes, but in this case I typically suggest the IOH kit for best improvement.
• Q: Can I buy just a Mouthpiece from you?
• A: Yes, I offer the machined LLY MP as a swapout. But the larger MP offered in the IOH kits will not simply swap out, they are offered in tested and proven turnkey kit form. They come with color installation guides, 100% money back guarantee, and tech support.
• Q: Will this increase my MPG?
• A: Yes. Anything that increases bottom line HP, without requiring added fuel, increases MPG. Typical gains range from 0.5 mpg, to 20% (2 MPG) for heavily laden trucks.
• Q: Will it pay for itself?
• A: It should many times. With fuel savings alone, it will reward the business operator with full payback in 4-6 weeks. Most people will get a slower payback, but this does not factor in the longevity benefits, which are harder to measure, but very significant. For the heavy tow user, total savings include fuel, turbo longevity, EGT related engine longevity, etc. Based on feedback, this is the best known hardware upgrade available for the LLY. It is also like having a turbo one size larger.
• Q: What can I do for my 06 or later truck?
• A: There is no improvement for these trucks, they already operate relatively restriction free, and as such, have better performance characteristics.

 

MEDIUM DUTY TRUCKS

• Q: I have an 04.5 or 05 LLY medium duty Kodiak/Topkick. Do I have the same problem?
• A: Yes, you do. Close study shows that these trucks have an almost identically designed plumbing flaw. Those complaining of cooling system heat issues, poor economy, and/or low power at higher elevations, will find the similar benefits as the LD trucks.
• Q: Does the light duty IOH kit fit my Kodiak/Topkick?
• A: No, but another has been provisioned for these owners, the K-IOH kit.  The Machine Mouthpiece is also available, a significant improvement to the stock MP.
• Q: I tow very heavy loads, 20,000 lbs, and experience hot temperatures. Will this help with that and reduce the amount of fan-on time?
• A: Yes. You will also have more extended range and towing power. Your turbo will run at a lower rpm also, so look for lowered EGT.
• Q: Do I need a new intake also.
• A: No. The medium duty intake is very well engineered to dampen IAT rise.

 

PERFORMANCE

• Q: What kind of performance benefits will I get from Induction Overhaul?
• A: Depends on your use and tune, and because of this, all results vary. High boost tunes at high elevations will see a 40-60 HP peak increase, depending on fueling. Race tunes, 40 HP. Stock tunes at sea level will be less, approx 15-20 HP. At altitudes over 6000 ft, add another 10-20 HP. The heat of summer will realize maximum benefits.
• Q: I have a Chevy Silverado LLY and I use 32 psi of boost, I want the best solution for my truck, I prefer to preserve stock appearance. What’s the best option for me?
• A: The IOH Kit, with internal high flow machining option. There is no better flowing alternative available… ANYWHERE.
• Q: I am planning to upgrade my turbo to the Cheetah, what do you suggest?
• A: see response above. The IOH kit is the perfect compliment, as is.
• Q: Will my track time improve?
• A: Yes. Typical ¼ mile times improve by 0.4-0.6 sec for stock turbos, 0.7-0.8 sec for larger turbochargers.
• Q: How much more boost should I be able to create safely with programming?
• A: D’pends. Usually about 4-5 psi. This assumes no changes to vane position. If willing to re-program vane position, you should be able to see 6 psi, or about 20% more mass air flow for the same turbo shaft speed.
• Q: Is there another way to observe or measure the benefits of the IOH kit?
• A: Yes, you can monitor vane position. You should see sharp reductions in the amount of vane closure required to make your programmed boost. This was one of the conclusions made by Joel Paynton in his MaxxTorque magazine validation testing. http://www.maxxtorque.com/summer-2008
• Q: Thank you for all that you have done, I have installed the IOH kit and am impressed with the performance enhancement so far. If I want to now maximize economy with tuning, what should I do?
• A: reduce boost 20% across the board, and advance timing 2-3 degrees. This simple technique will gain a 1-2 mpg increase, and keep the same power. Beyond this, consider “wastegate tuning”, an EFILive power tune I have created for the LLY. It dynamically adjusts timing and boost with these changing variables, to limit the production of waste induction heat.

 

PRODUCT SPECIFICS

• Q: How do I order your kit for my truck?
• A: Review the options here, and just email me at info@killerbeeperformance.com with your order request, and I will set up an invoice that permits the use of your choice of payment options, Paypal, Credit Card or check.
• Q: Is the core charge in addition to the price?
• A: Yes. It is refunded automatically if you used a credit card method.
• Q: I’m not much of a mechanic. How tough is this kit to install.
• A: About the same skill level as an oil change. 20 minutes and 2 tools. The color illustrated documentation is very easy to follow.
• Q: I’m a hobbyist DIY’er. Can’t I just buy a Kodiak Mouthpiece from various sources, and do this myself.
• A: Sure, though due to scarcity, it may take some effort to find one. There is fabrication skill involved and you have to decide if the amount of research time and detail involved with this option is worth the effort. If it is cost savings alone you are after, it’s often not worth the savings when the value of time is factored in.
• Q: What is the difference between the new IOH kit mouthpiece and the Kodiak Mouthpiece?
• A: The differences are substantial enough that they are not interchangeable. Ironically, the Kodiak MP is smaller, and dimensioned differently. It is also a bit more restrictive and does not allow you to use the stock black resonator. All these issues can be remedied with the modified MP used in the IOH kit which guarantees that your oem warranty is safe. However, the Kodiak part is better than the stock LLY MP.
• Q: I just want to buy a part from you.
• A: Sorry. They only start out life as an oem part. I modify these parts considerably to be made useful for the LLY, and to maximize fit and function, they go through a series of machining steps. They are then coupled with other temperature rated parts to complete the kit. I have done considerable legwork and testing to validate them. I don’t sell parts because I then have no control over how you use it, and I don’t want to be held responsible for misuse, or deal with complaints when the reality sets in that it is not simply a swap out part.
• Q: I want to remove the resonator, what are my options?
• A: I can’t really imagine why you would want to, but the resonator port opening can be capped (cap supplied), or simply use the Kodiak part, since it has no resonator port. Just be aware that your dealer might have a problem servicing your vehicle under warranty after your decision to scrap it. I do not recommend it.
• Q: You offer an internal hand machined flow treatment for $75. What benefit is that?
• A: For most recreational users, it is not required, the gains are modest. But if you tow with over 25 psi of boost, or race with over 30 psi, you should consider it worth the added cost. It removes imperfections that result from the mold and production process, providing detailed airflow improvement and smooth transitions for the least possible obstruction to airflow.
• Q: If I don’t agree with what you have stated after I install it, will you refund my purchase, excluding the shipping cost?
• A: Yes.  Just ship it back within the 30 day trial period.
• Q: Are they in stock?
• A: Usually. If they are not, you will know this before I accept your order.