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[Andrew]

depending on the heads, u could throw in a port and polish.......

[TRBenj]

a prop change will have a noticable performance upgrade. other than that cam, heads and intake.

Agreed. The single biggest upgrade you can make to improve overall performance is a new Acme. If you want to add hp, go with heads, intake and a cam.

Groovy, your 351w can use many automotive parts. However, ignition is not one of them- that must be marine specific. Before we start recommending specific upgrades, it would be helpful to know what you have in the boat now. Which motor (base 240/255hp or the Proboss 285/300hp), ignition system (Protec or regular distributor) and tranny (1:1 or 1.23:1) do you have?

And just to note, I wouldnt recommend a port and polish job on the heads. To have that done by a professional, you'll see bigger gains by spending the same amount on better heads.

[GroovyNautique]

I have the base model engine, regular distributor and the 1.23:1 tranny.

currently have a four blade 13x16 OJ prop

[TRBenj]

I have the base model engine, regular distributor and the 1.23:1 tranny.

currently have a four blade 13x16 OJ prop

That makes things simple since you have a standard rotation motor.

The first upgrade upgrade I would do is to add an Acme prop. If you plan to add some decent HP, go with the 1442. If you are going milder, go with the Acme 470. You then need to decide what your goals for power are, and plan the upgrades accordingly. Its easiest to do head-intake-cam all at the same time since the motor will be apart. The cam will be matched to your power goals and specific intake and head choices.

Surf on over to CorrectCraftFan.com and do some searching. Lots of info over there on how to beef up a 351w. Any specific questions, post em of send me a PM.

[MiracleDriver]

Tim, how do you know its standard rotation?

& what do you mean by 'standard'

I thought all nautiques were reverse rotation.

[GroovyNautique]

by going to the 3 blade prop, will I gain hole shot and lose some top end speed?

[GroovyNautique]

and thanks for all the info, I'll check out CCF.com for the rest!

[DanielC]

Standard rotation of an engine is this. If you are standing on the end of the engine that has the drive accessories, and looking toward the flywheel end, if the crankshaft rotates clockwise, that is a standard rotation engine. The 1.23 to 1 transmission reverses the rotation so the propeller is a right hand prop. Most Nautiques have a standard rotation engine.

[TRBenj]

Most Nautiques* have a standard rotation engine.

*Most Nautiques since 1989, that is. Otherwise, youre completely correct.

Nearly all pre '89 (when the 1.23 trans debuted) Nautiques used reverse rotation motors. That was the only way to turn a RH prop with the 1:1 transmissions.

Groovy, your logic on the prop is backwards- in general, 3-blades are more efficient, so they give up a little out of the hole but have the advantage on top end speed. The new Acme 3-blades offer the best of both worlds- due to their large blade area, they hold the advantage over the 4-blades in both holeshot and top speed.

[DanielC]

I know that in the past, CC used reverse rotation engines. I was not sure on the year of the switch to the 1.23 tranny, with standard rotation engines. Thanks for the info.
On my boat, I commonly run two different props. The OJ 13x16, and the Acme 422. Both 4 blade props. I feel I get a little better performance with the OJ prop, than with the Acme. The Acme seems to run a bit smoother. By better performance, the boat seems to have a slightly higher top speed, and pulls a bit harder. The motor will run slightly higher RPM with the OJ prop, that is consistent with the better performance. All my props have been to the prop shop at least once or more. I have three props. The two OJ props both ran smoother after the first time they went to the prop shop, but they seem to be a little more "buzzy" now. I have three props so I have a spare in case my spare prop is getting fixed.

[TRBenj]

On my boat, I commonly run two different props. The OJ 13x16, and the Acme 422. Both 4 blade props. I feel I get a little better performance with the OJ prop, than with the Acme.

I ran 7 different props a few weeks ago and recorded performance numbers (the writeup is in process). The lineup included the 13x16 Legend, 430 XMP (428 with extra cup), 422 and 4 different Acme 3-blades. I havent crunched all of the numbers yet, but I can tell you for sure that they wont agree with your impressions.

Youre right about one thing- the OJ Legend did turn more RPM than the 422 (~200). However, that didnt translate into speed or acceleration, as it slowed the boat down about 2MPH, and the holeshot was not impressive. For pure performance, I would rank the props (from best to worst): Acme 3-blades, Acme 422, OJ XMP, OJ Legend.

I cant comment on the difference in the ski wake, though in pictures the wake does not appear to change much (if at all). I didnt have time to ski them all.

[MiracleDriver]

sorry to hijack, just trying to get clear on the rotation.

nautiques reverse differently than most other boats. I thought this was because it was a "reverse rotation"

I have a 90 like yours Tim, with the 1:23: tranny.

is the motor standard rotation, but the reduction drive reverses the prop? now I'm all confused

so my 90 is a standard rotation motor, but a reverse or RH drive?

[darrel409]

The motor is standard rotation and your 1.23:1 pcm trans changes the rotation so the prop spins the "Correct Craft" way (RH).

[TRBenj]

MiracleDriver, Darrel is correct. If you look at your engine tag, you will notice that it begins PLD. The L denotes the LH rotation of the motor, which is reversed by the 1.23 tranny for a RH prop. Reverse rotation PCM 351's start with PRD.

[Rick]

I second the prop change. If you need more power and less top speed go down 2" of pitch. If you need more speed and less pull go up 2. Acme is really good a prop suggestions and usually will swap them till you are happy.