I got onto the previous thread a little late, and now it's locked from further reply. I just wanted to say that many people were touting the e-tec as the better engine based on what kind of evidence? Anecdotal or head to head competition? Well, I happened upon a copy of a test that Bass and Walleye Magazine did last October between 5 90hp motors: Honda, Suzi, Merc Opti, E-tec and Tohatsu tldi, and guess what? The Tohatsu beat all others in fuel economy, was quieter than the e-tec at WOT, and only slightly slower than the e-tec in accelaration. Here is the text of the article:<br /><br />Roarin' 90s <br />Five 90 hp outboards of every technology available duke it out on Mississippis bayous for bantamweight braggin rights <br /> <br />Bass and Walleye Boats <br />October 1, 2004 <br /> <br /> Email this article to a friend! <br /> <br /> <br /> <br />Pound for pound, they pack a mean punch. Were talking about the new bantamweight outboards 90 hp mills, to be exact. There have been a number of developments in this class including Evinrudes new E-Tec and Mercurys 1.5L OptiMax and it seemed like all the players, both four-stroke and direct-injected (DI) two-stroke, were ready to duke it out. But we knew we needed a huge venue for such a championship bout, so we turned loose five of the top engines on Mississippis bayous to see which ones would merely survive... and which ones would flourish. <br /><br />Besides the Rude and Merc, joining the fray on the DI side was Tohatsus 90 TLDI, while the four-stroke contingent was represented by Suzuki and Honda. Unfortunately, we did not get a chance to test the new EFI version of Yamahas F90 four-stroke, as production models were not yet available. We also didnt evaluate Nissans 90 TLDI and Johnsons 90 four-stroke, as Tohatsu and Suzuki make these engines, respectively, so the results would have been redundant. <br /><br />We chose the aluminum Triton 170 CC bay boat as our test bed. Rated for 90 hp, its a fast 17-footer that features a pad bottom with a modest 12 degrees of transom deadrise. Setup is critical with this hull, as it likes to be run with the engine set fairly high on the transom (see sidebar starting on page 22). The stock transom height is 22 inches and all of the outboards except Mercury were run with the engine mounted in the third hole. Mercury chose to use the second hole. <br /><br />THE RULES <br />Our shoot-out was conducted out of Aberdeen Marina on the Tennessee-Tombigbee Waterway in Aberdeen, Mississippi. The rules were simple. Triton graciously provided five identical 170 CC boats. The engine manufacturers were to supply an outboard and a representative to ensure the engine was properly rigged and propped. Each outboard had to remain within its recommended wide-open-throttle (WOT) operating range, and the prop had to be available through a dealers parts catalog. We want to point out that the Japanese manufacturers often buy props from Mercury and other suppliers such as PowerTech, Turbo and Solas. <br /><br />The representatives were allowed as much time as necessary to prepare the boats. Once they were happy with the setup, the actual tests were conducted by BWB Editor Steve Quinlan and yours truly. All evaluations were conducted in similar conditions, in the same manner, and all tests began with a full 6-gallon portable fuel tank. <br /><br />In alphabetical order, lets meet our players. <br /><br />EVINRUDE 90 E-TEC <br />At 305 pounds (all weights per manufacturers specs), Evinrudes new two-stroke design is the lightest of the engines tested. In fact, its 111 pounds lighter than the Suzuki, which was the heaviest of the group. In fairness, Suzukis I-4 block displaces 119 cubic inches (by far, the most in the group), compared to the I-3 <br /><br />E-Tecs 79 cubic inches. At 77 cid, only the Tohatsu displaces less. <br /><br />Perhaps due to its weight advantage, the Evinrude was a shade faster than the rest of the field, posting a two-way-average top speed of 49.9 mph good enough to edge Mercury by 0.2 mph. It was also the only engine to break 50 mph in a one-way run. The E-Tec is our acceleration champ, as well, with 0-to-30 mph times averaging 8.1 seconds. <br /><br />This DI two-stroke has a quiet idle. Although you can hear the clicking of the E-Tec injectors, its not really objectionable. Our sound meter showed it to be the loudest of all the competitors at optimum cruising speed, however, as we measured 88 decibels (dBa) at 3000 rpm and 27.4 mph just a shade more than the Tohatsu, Suzuki and Merc, but 4 dBa more than the Honda. It tied with Mercury for being the loudest at wide-open throttle, measuring 101 dBa. Even so, the E-Tec has a nice, tight sound. <br /><br />In terms of optimum cruising economy, the Evinrude finished in the middle of the pack. Unfortunately, our test engine had two faults. The first occurred at 1500 rpm, where the Evinrude was very rough running. Then, at 2000 rpm, it would not hold a constant rpm but would surge to 2500 or higher. The E-Tec injection system provides a very lean fuel charge at low rpm for exceptional slow speed economy, and we suspect that 2000 rpm is where the changeover occurs to a normal fuel/air mix. If so, this likely explains the surging. At 2000 rpm and 7.9 mph, this rig is about to climb onto plane and the surging will probably be inconsequential for most owners. <br /><br />BWB Field Editor Bill Grannis, our Johnson/Evinrude expert, tells us that this problem, which generally occurs on light or overpropped boats, has been addressed in a warranty bulletin by BRP titled Recalibration/Software Update. The software update that corrects this problem is available for 2004 models at dealers for no charge. The warranty bulletin states improvements are already incorporated in 2005 models. <br /><br />Otherwise, the California Air Resources Board (CARB) 3-star-rated E-Tec performed flawlessly throughout the balance of the rpm range. <br /><br />HONDA BF90 <br />Do you like a quiet outboard? From idle to WOT, the four-stroke Honda proved the quietest of the bunch. It did exceptionally well in fuel economy, too. We recorded 9.2 mpg at 3500 rpm and 29.3 mph. This is the fastest cruising speed measured a full 6 mph faster than Tohatsu, which placed first in cruising economy with a remarkable 9.7 mpg. <br /><br />Our Honda-powered Triton had an acceleration problem off the line. When we popped open the throttle too quickly, the engine would die. This can be attributed to federal emissions regulations and the carburetors. The idle mixture screws are capped to prevent them from being adjusted too far, and the factory settings are extremely lean to bring this model into emissions compliance. These are the same caps that made our carbureted cars run so poorly 25 years ago. <br /><br />The automotive industry overcame these problems with EFI systems, and since the Honda 90 is a fairly old four-stroke design, we suspect that a replacement model featuring EFI is not far down the line. <br /><br />The initial hesitation hurt Hondas 0-to-30 mph times, but once this CARB 3-star engine accelerated beyond idle speed, it punched hard and performed well throughout its powerband. <br /><br />MERCURY 90 OPTIMAX <br />Mercurys I-3 OptiMax is only half new, as its really just a 3.0L V-6 split in half. At 93 cubic inches, this CARB 3-star outboard is the largest and heaviest DI two-stroke in this test. As stated, the Merc was nearly as fast as the Evinrude, and tied with the E-Tec for being the noisiest at WOT. While the Mercurys noise is not objectionable, it does not have the tight, solid sound of the Evinrude. <br /><br />In our 0-to-30 mph acceleration runs, the OptiMax came in fourth, just 0.10 seconds shy of the third-place Tohatsus 9.3 second showing. And we were surprised to see it bring up the rear in optimum cruising economy. With the Merc strapped to its back, the Triton 170 CC managed 7.1 mpg at 3000 rpm and 24.0 mph. And while that speed is comparable to the economy-champion Tohatsu, it comes at 2.6 fewer mpg likely due in large part to increased drag. <br /><br />Mercury is the only company that ran with its engine mounted in the second hole. All the others used the third hole. Mercury had done some rigging work before we arrived. The OptiMax was originally mounted in the lowest hole, but there was no paint scuffing around the third hole, which leads us to conclude that they never tried the third hole. In our opinion, Mercury would have come out on top in the speed department if it had raised the engine one position. <br /><br />Although the Mercurys performance was satisfactory, the boat exhibited some of the porpoising problems described in the Triton sidebar, and its handling was not as crisp as the other setups. On the plus side, Mercs lower engine setting did help the 170 CC carve better turns. <br /><br />SUZUKI DF90 <br />As noted, the four-stroke DF90 has the largest displacement and weighs the most of the engines tested, mainly because Suzuki uses the same block for its 115 and 140 models. Thats nearly 25 percent heavier and 33 percent more displacement than the Evinrude and Tohatsu. <br /><br />The Suzuki didnt win any single category, but it fared well in most tests. With an elapsed time of 8.3 seconds, it was the second quickest from 0 to 30 mph just 0.2 mph behind Evinrude. It also finished second in quietness, just a decibel or two noisier than the Honda across the rpm range. <br /><br />Unofficially, it would have posted the third fastest top end, clocking 49.5 mph at 5800 rpm. Unfortunately, this is 300 rpm beyond the DF90s maximum recommended operating limit, which our rules dictate all engines must stay within (as did each of the other outboards). Matched to Tritons fleet, 17-foot bay boat, Suzukis 131/4x26-inch stainless three-blade the tallest available from the manufacturer was simply not enough wheel to rein it in on this application. Thats why in our performance charts youll see the official speed capped at 5500 rpm, where the Suzuki was running 44.4 mph. <br /><br />Even so, the CARB 3-star Suzukis acceleration times should lay to rest the notion that four-strokes are doggy out of the hole. By the same token, it is fair to point out its strong showing is due in part to Suzukis large displacement and that comes with a weight penalty. <br /><br />In terms of overall performance, the DF90 was a smooth operator. There were no flat spots or rough running throughout the acceleration curve, and the engine offered a pleasing, tight, four-stroke sound. <br /><br />TOHATSU 90 TLDI <br />The Tohatsu ran in the middle of the pack in all test parameters except cruising economy, where it shined above the rest. This DI two-stroke gives up approximately 2 percent in top speed to the Evinrude, but goes 10 percent farther on a tank of gas. Its displacement (77 vs. 79 cid) and weight (315 vs. 305 pounds) are similar to the E-Tec, although the Evinrude has slight advantages in both areas. <br /><br />The 90 TLDI was the quietest of the two-strokes at WOT. We recorded 99 dBa at the helm at 5700 rpm, which is 2 dBa less than the Merc and Evinrude. The Suzuki and Honda four-strokes were clearly quieter, though in fact, the Honda was significantly quieter at the same basic rpm. The Tohatsu is the oldest basic design of all the engines tested, and those who love the sound of a two-stroke will feel right at home with the 90 TLDI. It is not objectionably noisy, but, like the Mercury, it doesnt have the tight sound of the Evinrude or the lower-pitched sounds of the four-strokes. Its also the only engine in the group to merit a CARB 2-star rating; all the others are 3-star, ultra-low-emission designs. <br /><br />This outboard performed well throughout the rpm range, with no flat spots or misfires although it exhibited a vibration that is characteristic of a bent or poorly balanced prop. From past experience, we know this is not normal. Tohatsu used a Mercury Vengeance prop with a Flo-Torq II hub, and we have heard there are occasional vibration problems with this hub. Well give Tohatsu the benefit of the doubt on this issue but if contemplating a Tohatsu with a Mercury prop, check the prop for a vibration problem before laying down the hard cash. <br /><br />PHOTO FINISH <br />The most impressive aspect of our 90 shoot-out is the closeness of the results. With the exception of the over-revving Suzuki and again, this engine was limited by available props the difference between the slowest and fastest was 2.2 mph. <br /><br />Yet, when buying a 90 hp engine, raw speed is just one of many attributes a consumer looks at. After all, this is a fishing motor, not a drag motor. And not all boaters place equal emphasis on each of these categories. Some would say quietness is most important, while others would consider acceleration to be of greater value. Yet, fuel economy may carry the most weight for others. <br /><br />If quietness were our top consideration, wed have picked the Honda. If fuel economy had been the deciding factor, wed have given the nod to Tohatsu. However, we tend to favor engines that finish strong in multiple categories, and neither of these engines fared well in performance. So, while Mercury turned in the second-fastest top speed, it was slow out of the hole, and it was not only the loudest, but the thirstiest of the five engines tested. This leaves Suzuki and Evinrude. <br /><br />Though Suzuki did not finish first in any of the four categories tested, it was my pick. It was second only to Evinrude in acceleration by a mere 0.2 seconds and if allowed to over-rev, it finished third in top end (0.4 seconds behind Evinrude and 0.2 seconds behind Mercury). It was also quieter than the Evinrude not only at idle, but at cruise and wide-open throttle. <br /><br />I asked BWB Editor Steve Quinlan how he would rate the engines (after all, he was right beside me during each phase of testing). Like our readers, and like me, he values certain performance aspects more than others. Heres what he had to say: Sure, Suzukis four-year track record for that engine and great showing in most of the categories we tested made it a tougher contender than the spec boxes might indicate. Yet, when you add up the numbers, the Evinrude was slightly quicker, slightly faster and offered better fuel economy than the Suzuki. I also like the E-Tecs three-year/300-hour no-maintenance program. I disagree on the noise issue. I still like the growl of a two-stroke as long as its not unpleasant or overpowering. The E-Tecs growl is the sound of a tight machine. It doesnt have the rattling sound were accustomed to hearing from most two-strokes. <br /><br />Quinlan went on to say that theres no doubt in his mind that if the Suzuki had a bigger prop to keep it within its recommended wide-open-throttle range, it would have been the fastest engine of the bunch. However, a bigger prop would have knocked it down a notch in holeshot. How much, Quinlan says, I dont know. <br /><br />Though E-Tec is a rather new technology, Im confident its rock solid, he says. Evinrude is banking its reputation on it. All things considered, Id have to give the edge to Evinrude and call Suzuki a close second. <br /><br />Just as we dont see eye to eye on everything boat related, we have agreed to disagree here, and have declared it a split decision between Evinrude and Suzuki for bragging rights as the bayous top bantamweight. BWB
.<br />I always figured the American market wasnt thier bread & butter so they werent in a hurry to meet our EPA laws, but I'm not in the business..<br />So in other words, we can see cleaner Yamaha's & Tohatsu 2 strokes then the E Tec's soon..<br />Well, the way they copy each other's designs it wouldnt suprise me now that I think of it.