Q1: what should the position of the [Anti-Ventilation plate] be relative to the keel bottom of the hull when using an Evinrude E-TEC 90 on a 1989 GLS 17?
BACKSTORY
My latest project boat is a 1989 GLS 17 with E-TEC 90 turning a VIPER 17-pitch propeller. The rig includes a battery under the console and two 6-gallon on-deck fuel tanks under a seat.
PERFORMANCE CONCERNS
My first concern: when [accelerating at full-throttle from a standing start] the bow rises and the boat stands on end.
My second concern: If you accelerate more slowly onto plane the bow remains high until planing speed is reached.
Both of these behaviors do not make me happy.
Q2: what engine mounting height or other changes can reduced the extended bow rise while accelerating onto plane?
ENGINE INSTALLATION DETAILS
The E-TEC 90-HP engine was installed by a platinum-level Evinrude dealer, familiar with large boats in Pompano Beach. A straight edge was used to align the keel bottom to the engine [Anti-Ventilation] plate. How this position would be described in terms of number of holes-up-from lowest mounting height is unknown to me.
OTHER MODELS
Surely, people with Stripers, Newports, and Super Sports don't have these concerns [about bow rise while accelerating onto to plane]
1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
If you provide a photograph of the engine mounting showing the number of unoccupied mounting holes that are above the upper mounting bolt, the engine mounting height in terms of the number of holes up from lowest possible position can easily be deduced from this visual evidence.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
A measurement of the difference in vertical height between the bottom of the hull keel and the Anti-Ventilation plate of an outboard engine when properly trimmed is no longer a benchmark for determining best engine mounting height.glen1941 wrote:Q1: what should the position of the [Anti-Ventilation plate] be relative to the keel bottom of the hull when using an Evinrude E-TEC 90 on a 1989 GLS 17?
For best maximum boat speed in calm water when the engine is trimmed with the drive shaft orthogonal to the water and a modern steel propeller is being used, the water flow at the Anti-Ventilation plate should just be at or just below the A-V plate, as long as this mounting height provides the engine cooling water pressure to remain in the necessary recommended operating range.
For good performance that might sacrifice a small bit of maximum top speed, a slightly lower engine mounting height may be preferred, particularly if the boat will often be operating in rough or confused seas, and the concern is more to avoid propeller ventilation, particularly when making turns at speed.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Jim, Thanks. A photograph might help, but this being my fourth Boston Whaler boat and having read many many posts on this subject, I can say that the current mounting height position of the engine is "one hole up" (with the hardware as) installed. However, the installer used the holes from the previous engine, a YAMAHA 75-HP two-stroke-power-cycle model. My present engine is a Evinrude E-TEC 90-HP [two-stroke-power-cycle direct-injection]. The mechanical engineer in me says that the cause of the bow being way up until planing, and the OMG business when "punched" is because the engine is installed too low. The boat is rotating around the propeller.
As you have said, only using a measurement from bottom of keel to anti-vent plate is not the final answer; for me, it is a decent starting point however. So, this week I am having a local shop raise the engine [mounting height on the transom by] 2-inches ±. Then I will run it [i.e. the boat] and change it [i.e. the engine mounting height] if required, on order to get the anti-ventilation plate riding on the wake at cruise when trimmed.
As you have said, only using a measurement from bottom of keel to anti-vent plate is not the final answer; for me, it is a decent starting point however. So, this week I am having a local shop raise the engine [mounting height on the transom by] 2-inches ±. Then I will run it [i.e. the boat] and change it [i.e. the engine mounting height] if required, on order to get the anti-ventilation plate riding on the wake at cruise when trimmed.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Adjusting the engine height is so easy that it may be worth some experimentation. The adjustment can be made at the launch site so it can be accomplished single handed in a few minutes. You may want to keep a four blade stainless steel propeller in mind. "Generally", a four blade propeller will provide much better hole shot with a small loss of top speed.
Butch
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
The location of the holes in the transom should be as recommended by the BIA guidelines. See this article for a dimensional drawing showing where the transom holes ought to be placed:
Transom Mounting Hole Layout
https://continuouswave.com/forum/viewto ... 808#p33740
Typically if would be impossible to mount an outboard engine “too low” by drilling the transom holes lower than suggested because most outboard engines have a mounting bracket that has a lip at the upper end, and If the transom holes were lower than recommended the engine mounting bracket could not fit flush onto the transom when mounted at the lowest height.
As for raising the engine “2-inches” higher than when it is already one-hole-up-from-lowest position, that won’t be convenient because the spacing of the mounting holes on the engine bracket for the upper bolts are at 3/4-inch intervals. You could raise the engine to three-holes up from lowest, which would be 1-1/2-inches higher that the current one-hole-up mounting height you are reporting.
Q3: what is the full model identification for the E-TEC engine?
Perhaps the engine is an XL model, designed for 25-inch transom instead of a 20-inch transom.
Transom Mounting Hole Layout
https://continuouswave.com/forum/viewto ... 808#p33740
Typically if would be impossible to mount an outboard engine “too low” by drilling the transom holes lower than suggested because most outboard engines have a mounting bracket that has a lip at the upper end, and If the transom holes were lower than recommended the engine mounting bracket could not fit flush onto the transom when mounted at the lowest height.
As for raising the engine “2-inches” higher than when it is already one-hole-up-from-lowest position, that won’t be convenient because the spacing of the mounting holes on the engine bracket for the upper bolts are at 3/4-inch intervals. You could raise the engine to three-holes up from lowest, which would be 1-1/2-inches higher that the current one-hole-up mounting height you are reporting.
Q3: what is the full model identification for the E-TEC engine?
Perhaps the engine is an XL model, designed for 25-inch transom instead of a 20-inch transom.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
I just put a five-feet-long level on the keel, and with the boat and engine level, found the AV plate is two-inches above the keel. This is contrary to what the installer told me he had done.
The engine mounting height is "one hole up" and there are no empty holes in the transom.
The only times I have used the boat were in a choppy canal in Pompano Beach and fairly bumpy seas in Sanibel, and that may not have been a fair test.
Without both [the GLS and MONTAUK] boats to compare, my belief is that the helm seat, battery and fuel tanks are all further aft in the GLS than the Montauk--why did I sell that beauty?
From the CW reference, the GLS is lighter than the Montauk by about 150-lbs.
Again, my impression is the engine is rotating up the bow, even when trimmed in, instead of pushing it forward.
The full model identification E90DSLAFA.
The propeller is a stainless steel VIPER model. While the installer-dealer said that it was a 17-pitch, I cannot find any stampings on the propeller to confirm.
I thought the easy answer was going to be to raise the engine mounting height two inches and then experiment, but raising it two-inches from where it is now seems wrong.
I want to do something to improve the situation before putting it in the lake here, but not sure what to do.
I look forward to your counsel. Glen
The engine mounting height is "one hole up" and there are no empty holes in the transom.
The only times I have used the boat were in a choppy canal in Pompano Beach and fairly bumpy seas in Sanibel, and that may not have been a fair test.
Without both [the GLS and MONTAUK] boats to compare, my belief is that the helm seat, battery and fuel tanks are all further aft in the GLS than the Montauk--why did I sell that beauty?
From the CW reference, the GLS is lighter than the Montauk by about 150-lbs.
Again, my impression is the engine is rotating up the bow, even when trimmed in, instead of pushing it forward.
The full model identification E90DSLAFA.
The propeller is a stainless steel VIPER model. While the installer-dealer said that it was a 17-pitch, I cannot find any stampings on the propeller to confirm.
I thought the easy answer was going to be to raise the engine mounting height two inches and then experiment, but raising it two-inches from where it is now seems wrong.
I want to do something to improve the situation before putting it in the lake here, but not sure what to do.
I look forward to your counsel. Glen
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Thanks for confirming the full model designator for the E-TEC is E90DSLAFA.
That decodes as an Evinrude E-TEC 90-HP 20-inch-shaft produced some time after c.2012 in the third major production variant. The "S" designator seems odd, but it probably indicates "saltwater" model.
That decodes as an Evinrude E-TEC 90-HP 20-inch-shaft produced some time after c.2012 in the third major production variant. The "S" designator seems odd, but it probably indicates "saltwater" model.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Thanks Jim, The E-TEC engine does [have decal that ] say "Saltwater" [on the cowling]. I have not tried to determine what makes the “Saltwater” engine different than a non-Saltwater, but will [look for information on the difference].
I am towing the boat to Viking to have them raise the engine mounting height to "two holes up", or another 3/4-inch higher.
I am starting to believe, and I hope, that the bow raise business might be operator error.
After Viking raises the engine mounting height to two-holes-up position, will take [the boat] to Keowee [unclear, perhaps some body of water]. I will make sure that I start [a test of how the hull behaves when accelerating onto plane] with the engine trimmed in all the way.
I could not find any stampings [that indicate the propeller dimensions] on the propeller, but it is a big propeller. I don't remember the VIPER [propeller that I used] on the MONTAUK being this large.
I am towing the boat to Viking to have them raise the engine mounting height to "two holes up", or another 3/4-inch higher.
I am starting to believe, and I hope, that the bow raise business might be operator error.
After Viking raises the engine mounting height to two-holes-up position, will take [the boat] to Keowee [unclear, perhaps some body of water]. I will make sure that I start [a test of how the hull behaves when accelerating onto plane] with the engine trimmed in all the way.
I could not find any stampings [that indicate the propeller dimensions] on the propeller, but it is a big propeller. I don't remember the VIPER [propeller that I used] on the MONTAUK being this large.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
I do not think that the “Saltwater” designation on the engine will have any influence on the tendency of the hull to exhibit bow rise while accelerating onto plane.
Re beginning the acceleration onto plane by having the engine trim set to maximum trim-in: that should be very helpful in reducing the tendency for the hull to have a bow-high attitude as it tries to climb over its own bow wave and rise unto plane.
The E-TEC engine should have plenty of power in the lower-mid RPM range to be able to easily push the 17-foot hull over its own bow wave and get “up” onto a planing trim. Of course, the operator needs to manage the throttle position to allow the engine to produce the needed power. If the throttle setting is too low, the hull may get stuck in a bow-up trim while is is still trying to climb up the bow wave.
Also, for a propeller to lack all markings of its model or pitch or part number would be very unusual.
Re beginning the acceleration onto plane by having the engine trim set to maximum trim-in: that should be very helpful in reducing the tendency for the hull to have a bow-high attitude as it tries to climb over its own bow wave and rise unto plane.
The E-TEC engine should have plenty of power in the lower-mid RPM range to be able to easily push the 17-foot hull over its own bow wave and get “up” onto a planing trim. Of course, the operator needs to manage the throttle position to allow the engine to produce the needed power. If the throttle setting is too low, the hull may get stuck in a bow-up trim while is is still trying to climb up the bow wave.
Also, for a propeller to lack all markings of its model or pitch or part number would be very unusual.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
jimh--Thanks.
I read the information on the "Saltwater" modell of the E-TEC, and I found it contained good stuff to combat internal and external corrosion
I have my fingers crossed that when I get boat back and out on the lake, that trimmingin all the way to start [the acceleration onto plane] will confirm that there was never a real problem, and that all along the cause of the bow rise was me being in difficult situations and being rushed.
The dealer found the propeller designation on the thrust washer: 13-7/8-diameter and 17-pitch. [This propeller has the] same [dimensions as the] old VIPER [that was on the MONTAUK 17].
I read the information on the "Saltwater" modell of the E-TEC, and I found it contained good stuff to combat internal and external corrosion
I have my fingers crossed that when I get boat back and out on the lake, that trimmingin all the way to start [the acceleration onto plane] will confirm that there was never a real problem, and that all along the cause of the bow rise was me being in difficult situations and being rushed.
The dealer found the propeller designation on the thrust washer: 13-7/8-diameter and 17-pitch. [This propeller has the] same [dimensions as the] old VIPER [that was on the MONTAUK 17].
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
That is very odd. The thrust washer is not a part of the propeller. The same thrust washer would be used with all propellers.The thrust washer is located on the propeller shaft ahead of the propeller, and it is designed to transmit the thrust force onto the propeller shaft.glen1941 wrote:The dealer found the propeller designation on the thrust washer: 13-7/8-diameter and 17-pitch. [This propeller has the] same [dimensions as the] old VIPER [that was on the MONTAUK 17].
More likely the dealer found the markings on the propeller but hidden under a washer or spacer that is under the propeller retainer nut.
Fig. 1. A view of a propeller with the embossed diameter, pitch, and part numbers visible under the retainer nut, washer and spacer. On a smaller propeller a spacer or washer could be large enough to obscure those markings, or there could be a build up of soot from the exhaust that obscures the numbers.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
I put the boat in [unclear, perhaps means a local lake] on [Saturday, June 6, 2026], a bumpy day. The dealer had raised the [engine mounting height] to "two holes up", and the A-V plate is now 2-3/4-inches above the keel. The static waterline was observed at just [below] the the transom drains, with the boat having no one aboard but with 12-gallons fuel and a battery. With a slightly-overweight pilot onboard, there was no water [in the engine splash well].
PROPELLER TEST
The [E-TEC 90-HP engine production epoch] is 2017. The engine has about 400-hours. It was checked-out by an Evinrude "Platinum-level" dealer just before I bought it. The hull has no anti-fouling paint.
[Readers: you need to recall that the propeller being tested is described as have 13-7/8-inch diameter and 17-pitch, is made of stainless steel, and is a VIPER model, which if the propeller is from Evinrude means a three-bladed propeller with some blade rake designed for high-speed.]
With the engine trimmed-in all the way, the boat was accelerated slowly, and the bow did not rise. (Yeah--no structural concern).
In some quiet water. the boat tried to leap out of water. The engine accelerated to 5,500-RPM and produced a boat speed of 33-MPH. I was expecting the the engine to accelerate to more than 5,500-RPM and for the boat speed to be about 38-MPH.
[I infer that] that going to a higher pitch to obtain more boat speed would only bring down the engine speed.
Perhaps the propeller is not actually what the thrust washer says it is. [Moderator's note: probably does NOT mean thrust washer].
Give me suggestions of how in increase engine speed at full throttle and also to increase boat speed at full throttle.
PROPELLER TEST
The [E-TEC 90-HP engine production epoch] is 2017. The engine has about 400-hours. It was checked-out by an Evinrude "Platinum-level" dealer just before I bought it. The hull has no anti-fouling paint.
[Readers: you need to recall that the propeller being tested is described as have 13-7/8-inch diameter and 17-pitch, is made of stainless steel, and is a VIPER model, which if the propeller is from Evinrude means a three-bladed propeller with some blade rake designed for high-speed.]
With the engine trimmed-in all the way, the boat was accelerated slowly, and the bow did not rise. (Yeah--no structural concern).
In some quiet water. the boat tried to leap out of water. The engine accelerated to 5,500-RPM and produced a boat speed of 33-MPH. I was expecting the the engine to accelerate to more than 5,500-RPM and for the boat speed to be about 38-MPH.
[I infer that] that going to a higher pitch to obtain more boat speed would only bring down the engine speed.
Perhaps the propeller is not actually what the thrust washer says it is. [Moderator's note: probably does NOT mean thrust washer].
Give me suggestions of how in increase engine speed at full throttle and also to increase boat speed at full throttle.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
The dealer's technician only saw the 13 7/8 x 17 on the washer. He did nothing more than look as I did.
I will remove propeller and take it to a good peropeller shop to find out what the propeller dimensions are. If the propeller turns out to If it turns out to really be a 13-7/8 x 17-pitch, then the plot thickens.
I will remove propeller and take it to a good peropeller shop to find out what the propeller dimensions are. If the propeller turns out to If it turns out to really be a 13-7/8 x 17-pitch, then the plot thickens.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Your description of the component on which you can see the propeller dimensions as "the thrust washer" is probably not accurate. A thrust washer is the first element placed onto the propeller shaft during installation of a propeller. The propeller hub completely conceals the thrust washer. There is no way to see the thrust washer when the propeller is in place on the drive shaft.
To allow readers to better understand where you are seeing the propeller dimensions inscribed on some component of the propeller assembly, please show a photograph of the inscription that you and the dealer's technician can see while the propeller is installed on the engine propeller shaft.
I don't understand your suspicions that the propeller dimensions you are seeing are somehow NOT the proper dimensions for the propeller. There is no normal practice in which some element of the propeller assembly other than the propeller itself would be marked with the propeller dimension,
Regarding how to get the engine to accelerate at full throttle to a higher engine speed, you need to compare the observed 5,500-RPM at full-throttle with the recommended optimum engine full-throttle engine RPM in the owner's manual. Or see my article on E-TEC engine speed recommendations at
https://continuouswave.com/whaler/refer ... neRPM.html
Note that for a c.2012 or newer 90-HP engine, the optimum full-throttle engine speed is 5,200-RPM. That engine speed generally means the speed where peak horsepower and torque occur. So in your situation, the propeller you tested with is already allowing the engine to run above the optimum speed, but just be 300-RPM. I don't think you are going to be able to unlock 5-MPH of hidden boat speed with a different propeller, but you are welcome to pursue that goal.
Also, you should carefully observe the position of the A-V plate compared to the water flow at the A-V Plate to see if the A-V plate is running at the top of the water flow. It the A-V plate is still buried in the water flow, then you MIGHT be able to improve the top boat speed by raising the engine slightly. However, before going higher than two-holes-up mounting height you should have some instrumentation to monitor the cooling water pressure. If the engine mounting is too high, the cooling water pressure will fall off. Loss of cooling water at full-throttle operation can cause the engine temperature to rise higher than normal.
To allow readers to better understand where you are seeing the propeller dimensions inscribed on some component of the propeller assembly, please show a photograph of the inscription that you and the dealer's technician can see while the propeller is installed on the engine propeller shaft.
I don't understand your suspicions that the propeller dimensions you are seeing are somehow NOT the proper dimensions for the propeller. There is no normal practice in which some element of the propeller assembly other than the propeller itself would be marked with the propeller dimension,
Regarding how to get the engine to accelerate at full throttle to a higher engine speed, you need to compare the observed 5,500-RPM at full-throttle with the recommended optimum engine full-throttle engine RPM in the owner's manual. Or see my article on E-TEC engine speed recommendations at
https://continuouswave.com/whaler/refer ... neRPM.html
Note that for a c.2012 or newer 90-HP engine, the optimum full-throttle engine speed is 5,200-RPM. That engine speed generally means the speed where peak horsepower and torque occur. So in your situation, the propeller you tested with is already allowing the engine to run above the optimum speed, but just be 300-RPM. I don't think you are going to be able to unlock 5-MPH of hidden boat speed with a different propeller, but you are welcome to pursue that goal.
Also, you should carefully observe the position of the A-V plate compared to the water flow at the A-V Plate to see if the A-V plate is running at the top of the water flow. It the A-V plate is still buried in the water flow, then you MIGHT be able to improve the top boat speed by raising the engine slightly. However, before going higher than two-holes-up mounting height you should have some instrumentation to monitor the cooling water pressure. If the engine mounting is too high, the cooling water pressure will fall off. Loss of cooling water at full-throttle operation can cause the engine temperature to rise higher than normal.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
if you provide the GEAR RATIO of your engine, then your performance data could be better assessed.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
I removed the propeller and found 13 7/8 x 17 stamped into the hub
No joy that a propeller might be the easy answer.
The engine gear ratio is 2:1.
During the short [time the engine throttle setting was] WOT my onboard passenger was an elderly person with a bad back, and thus I could not do any sustained data collection.
The engine is now 2-3/4-inches above the keel.
[On the] next trip [I] will get into flat water and observe where A-V plate is located in relation to the wake. Also, [I will] experiment with trimming to sweet spot.
In the very short and bouncy WOT period, I saw [engine speed was] 5000-RPM and [boat speed was about] 33 or 34-MPH.
I believe the [engine mounting height position is now] at the right height and the propellet is correct—as was for the Montauk.
If trimming does not produce [an engine speed of] approximately one 5,300-RPM and [a boat speed of] 38-MPH, what are other possibilities for improvement?
No joy that a propeller might be the easy answer.
The engine gear ratio is 2:1.
During the short [time the engine throttle setting was] WOT my onboard passenger was an elderly person with a bad back, and thus I could not do any sustained data collection.
The engine is now 2-3/4-inches above the keel.
[On the] next trip [I] will get into flat water and observe where A-V plate is located in relation to the wake. Also, [I will] experiment with trimming to sweet spot.
In the very short and bouncy WOT period, I saw [engine speed was] 5000-RPM and [boat speed was about] 33 or 34-MPH.
I believe the [engine mounting height position is now] at the right height and the propellet is correct—as was for the Montauk.
If trimming does not produce [an engine speed of] approximately one 5,300-RPM and [a boat speed of] 38-MPH, what are other possibilities for improvement?
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Assuming you have the engine operating at the recommended optimum engine speed at full throttle, improvement in boat speed can be provided by reducing the total weight on the boat and by testing with other propellers, particularly propellers which are advertised as being focused on producing more boat speed. However, specialized propellers can be very expensive, such as the Mercury Marine ENERTIA ECO XP RACING model, a hand finished custom propeller that sells for about $1,300.glen1941 wrote:If trimming does not produce [an engine speed of] approximately 5,300-RPM and [a boat speed of] 38-MPH, what are other possibilities for improvement?
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
That sound like the engine has fallen off the boat and is mostly submerged in the water.glen1941 wrote:The engine is now 2-3/4-inches above the keel.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
You probably don’t need to get into the water. You can observe the position of the A-V plate while still in the boat.glen1941 wrote:[On the ] next trip [I] will get into flat water and observe where A-V plate is located in relation to the wake.
Also, the wake is always behind the A-V plate when the boat is underway and making forward propulsion.
You need to look over the transom and downward at the engine gear case, noting the relative position of the A-V plate to the waterline, as the water flows over the gear case. Please read the posts at
A-V Plate Photographs
https://continuouswave.com/forum/viewto ... f=7&t=8605
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
With that information you now can use the propeller calculator to compute SLIP from you engine speed, boat speed, and pitch.glen1941 wrote:The engine gear ratio is 2:1.
See
https://continuouswave.com/calculators/propCalc.php
Using your latest test data of 5000-RPM and 34-MPH, the SLIP was 15, which is higher than expected.
Your goal of 5200 to 5300-RPM and 38-MPH would require the SLIP to be about 9 or 10.
Re: 1989 GLS 17 E-TEC 90 Bow Rise While Accelerating
Jim--who said that you don't have a sense of humor.
[I] will [conduct some performance tests in] some quiet water, [set the throttle to allow the engine to accelerate to] 4000-RPM, trim [the engine] to sweet spot, let a friend take the wheel, and go back to take photos of the A-V plate in the boat wake.
I hope [performing the steps listed above] will answer that my goals have mostly been met. Maximum [possible] boat speed is not a priority; it is only an indication of overall boat performance. My real goal is a solid cruise at 4000-RPM at a boat speed of about 25-MPH.
ASIDE
I was reminded after the most recent (and only my third) trip that the E-TEC engine does not use [much] fuel. [My observations were] not analytical, just that after a half-hour-long [or longer] cruise, the [fuel tank level gauge] needle barely got off the peg from FULL on a 6-gallon fuel tank.
In a week I will have more [performance and fuel consumption data]
Thanks, Glen
[I] will [conduct some performance tests in] some quiet water, [set the throttle to allow the engine to accelerate to] 4000-RPM, trim [the engine] to sweet spot, let a friend take the wheel, and go back to take photos of the A-V plate in the boat wake.
I hope [performing the steps listed above] will answer that my goals have mostly been met. Maximum [possible] boat speed is not a priority; it is only an indication of overall boat performance. My real goal is a solid cruise at 4000-RPM at a boat speed of about 25-MPH.
ASIDE
I was reminded after the most recent (and only my third) trip that the E-TEC engine does not use [much] fuel. [My observations were] not analytical, just that after a half-hour-long [or longer] cruise, the [fuel tank level gauge] needle barely got off the peg from FULL on a 6-gallon fuel tank.
In a week I will have more [performance and fuel consumption data]
Thanks, Glen