Sunday, July 17, 2011

Mitigating Innovation Risk Via Testing

I received an email last week from a supplier (and friendly competitor) expressing concern about the clamps that we were using in our new ULTRAliteLINES. His concern was based on the fact that Gates, the manufacturer of the clamps, recommends them 'for vehicle coolant hose only'. I very much appreciated the feedback from him as it made me realize that others would also raise this concern - even though we are using it with hose engineered for coolant, oil and other fluids. So this blog entry serves to show our approach to insuring the performance of our product.

We knew our kit was a novel application of these components and did not know of any other companies that were using it this way. These lightweight Startlite hose, clamps and BSP fittings, were so cool (to us geeks) that we wanted to determine if they were fit for use in our application. Since coolant and oil as fluids look extremely similar to each other from the clamp's perspective. The only system differences are a small temp difference (coolant goes to 240F or so, oil to 270F) and the significant difference of pressure (15psi vs 100psi). The material properties are irrelevant to our hose system as neither fluid comes in contact with the clamp since our arrangement is over a barbed fitting, not a reused hose that could have oil on it. Therefore, pressure capability was the only real concern for our testing to investigate.

We felt spending the time and money to conduct track and lab testing would be the right path for this kit. It added 4 months to our development schedule but clearly needed to be done as we knew of no others who run this combination.

Ryan, who developed the ULTRAliteLINES, and I have a combined 25+yrs in the OE and Tier 1 auto industry. I spent 12yrs developing new products at 3M Automotive and subjecting these parts to OE specification and internal tests. Developing lab tests that would predict the lifetime of a part was always a Holy Grailish endeavor. There are committees of scientists and engineers who work towards striking the right balance between real world testing and simulated testing done in a lab. We decided a combination of lab with actual in-car testing would be the best indicator of how the product would hold up. Frankly, thoroughly testing this creative 'joint' would be the only thing that would allow us to sleep at night!

Laboratory tests:
We found a lab in MI that specializes in automotive line and fitting testing. They would be able to subject our kit to extreme conditions we could never replicate on the street or track. We sent them three samples of our kit and had them run two types of tests:
  1. Pressure Proof: 150degC@150psi for 30minutes and check for leaks
  2. Burst: increase pressure until failure
These tests represent extreme conditions that would never be seen in our cars. But by testing in this manner, we can fatigue the product and try to extract a failure. Accelerated tests can help predict potential failures, so extreme conditions are warranted. Since our budget did not allow optimization of this joint, we did not test various combinations. We only tested the configuration that we felt would be the best for our kit.

We created a marketing piece that shows the test results. You can see it here: LAB results. Essentially we passed the Pressure Proof tests and showed a safety factor of 3 to 5 times on the Burst test. This test is quite extreme as it is run immediately after the Pressure Proof test. Basically, the fittings blew out of the hose at pressures that were 3 to 5 times higher than they would ever see - even at peak operating levels. Frankly the test showed that the joint was withstanding 6 times normal operating pressures. As an engineer, this is a comforting margin and insures blissful sleep.

Track testing:
Subjecting parts to the track can be some of the best testing possible. This testing will insure that the cars can run even more reliably on the street. We installed the ULTRAliteLINES onto our Blue Car, a 2004 Elise. We initially ran it at the Big Track at Willow Springs, then at CA Speedway (Auto Club Speedway) and then finally at Laguna Seca. Here is a video from Laguna Seca: Blue@Laguna. We were testing several other products as well but the ULTRAliteLINES were run for a total of 11hrs (including dyno, etc) and approx. 360 track miles.
We used our AiM data system to record key parameters like oil temp and pressure. We also reviewed the lateral acceleration numbers to see how the pressures were holding up with our gPAN. The car showed oil temps of approx 200degF which is well under the 300deg F used in the Pressure Proof testing. The actual oil pressures we logged ranged from the high 40s psi to the low 60s psi. This was a third to half of what was used in the lab testing and far, far below the Burst test results of 344, 452, 565 psi. Ryan's OE experience suggested that a peak pressure of 100psi would be the extreme level experienced by our lines.

Other Considerations:
Proper component selection is key for a reliable system. Each of the parts we chose, come from reputable automotive companies who have done extensive testing. We simply supplemented their work with tests that were specific to our needs.

The Aeroquip Startlite hose has been used for fuel, oil and coolant applications successfully and has been fully tested by Eaton Corp. The braided hose actually imparts a clamping force onto the fittings, much like a 'Chinese Finger Trap' when you pull it. The Lotus twin oil coolers utilizes a fair amount of rubber hose. This became a clear opportunity, for weight reduction, if we used Startlite, since it is 40% lighter than typical rubber hose.

The Gates clamps were the newest and novelist item in our system. They have the ability to dynamically adjust compression based on temp. They also work very well when applied over hose/fitting barbs as they have much more clamp surface area and better conform the hose to the fitting barbs. The Gates clamps also claim to be impervious to ALL automotive type fluids.

Combining all these features made good engineering sense to us. We just need some testing to insure we were onto a good thing...and separate us from the typical approach that is used in the aftermarket.

Options For the Ultra Cautious:
I recognize that some in our community may still want more security. For them, I suggest the tried and true hose clamp. They can easily be added as a secondary clamp over our Gates clamps or as the primary clamp. They add just a tad bit more weight...I suspect Colin Chapman would simply run our kit as is...

Tuesday, July 5, 2011

Blue Car Testing @ Laguna Seca

The next round of Lotus Cup took place at Laguna Seca. We brought our Elise out for additional testing:
  1. Oil Cooler lines
  2. KATANA265
  3. Brake Relocation: Carbotech pad test
  4. Larini 8" (ultra quiet)
  5. FuelSafe Fuel cell
The boys had to swap out the trans after our last trackday and refitted the conventional gearbox with the Jubu 3rd,4th & Final Drive with the OS Giken LSD.

Oil Cooler Lines: We ran these lines again this weekend and had no problems. Our kit uses Aeroquip's Startlite hose with BSP fittings and a novel clamping system. Our clamp is very clean and compact which will make installation much easier. Our independent lab testing and the 6 trackdays has made us confident that our solution is ready for sale. We should have them available within a week or two.
KATANA265: Another three days of full throttle track use has us pleased with this solution. The AFRs & EGTs are looking safe and we believe we are ready to release the kit.

We believe that Hp north of the KATANA265 will result in problems with a stock transmission. We've witnessed another racer's 300+hp Exige lose 3rd gear at Laguna. We recognize that the allure of big Hp is hard to resist but we hope that folks will recognize what they are getting into. We are still waiting for a reply from Jubu/Drexler on the status of our Dogbox failure from the Fontana event. I think trans failures will become more common as the cars get more power and run slicks on the track.

Front Brake Caliper Relocation: I ran the car with the Carbotech pads and was very pleased with the XP12 & XP8 in the rear. The car did not have any of the nervousness that I had experienced at Willow Springs during our initial test. The pads work well and can be trail braked easily. They are not very grabby and allow a smoother release. I think that a more aggressive pad can be tried on the rear for sure. We'll get to that next time!

Larini 8" ULTRA Quiet: We ran a stock Exige S muffler to start our weekend to make sure the car was very quiet. Laguna has a very strict noise limit which has resulted in many racers trying different muffler contraptions: see previous post. Our car has several upgrades that would add to the noise like the HKS intake, Larini header/straight pipe and Jubu Final Drive. But with the stock Exige S muffler we blew a 88dB - so were well under the limit. The car felt a bit slower possibly because of the added restriction. We brought a new Larini 8" ULTRA Quiet with a special wrap that quiets the system over a standard Larini8"by an additional 2-3 dB. I wanted to test this system to see if it might be close. We installed it before the last session and went out for a sound check. The car sounds much better but I also knew right away that it was too loud! The car felt much faster going up the hills than before but ultimately blew a 98dB!!! Well, they black flagged me pretty quickly and I returned to the pits. Sound can be a difficult thing to measure properly in track conditions but we are so far over the limit that this muffler will not likely work for other heavily modified cars. This muffler will work perfectly with a NA car and possibly with an Exige S with stock intake/header/cat.

Fuel Safe Fuel Cell: We continued to run the car with the cell. Everything worked fine with the exception of one discovery. The system baffles the fuel in the fuel pump cavity too well. This results in the fuel gauge reading a higher amount than what is contained in the whole tank. Essentially the car can be down to a couple of gallons of fuel and system will trap it in this cavity that holds the pump and the fuel level float. The float will assume that the tank is higher than it actually is. The stock fuel tank has a bleed so that the fuel can slowly level itself when the car is sitting. We've contacted Fuel Safe to see if there is a good solution or drivers will need to monitor their fuel consumption.

Overall the weekend was a great success. We supported two Spec Elise clients along with Blue. None of the cars broke down and I was able to get my times down to 1min43s. I made one shock change that felt like an improvement but did not have much time to tinker with settings. With some coaching (and some new tires)I think I can carve another couple of seconds - maybe even break 1min40. That 'll have to wait till next year or my dreams! Our AiM data collected plenty of great info including the fact that car pulled 1.5gs - so I know we continue to stress the various products well. We have many more items in our pipe so this arduous testing must continue....8^)