Need a spare prop -have a 1235

[EricU]

I just sold my spare prop, a 1617 and now need a new spare for my old (08) RZ4 with the 340 (I think).

I am currently running a 1235 and wonder if I should try a 2079 or something else...

We both board and surf (hopefully) and have the potential to run a LOT of ballast (over 4k lbs) though I haven't really had the boat dialed in yet

• Any suggestions?

[Ewok]

Call acme directly and they will ask you lots of questions and they will give you their recommendation. Probably the 1235.

[shawndoggy]

Properly (ha ha pun intended) propping your boat is a function of being able to hit max operating range (4800 rpms for a 5.7L motor) with all your ballast. If you can't push the RPMs that high when slammed, then you need a lower pitched prop.

[talltigeguy]

Properly (ha ha pun intended) propping your boat is a function of being able to hit max operating range (4800 rpms for a 5.7L motor) with all your ballast. If you can't push the RPMs that high when slammed, then you need a lower pitched prop.

I've never tried to get up to max RPM with my boat fully weighted. Interesting concept and I could see that as a measure of how much you are lugging the motor, but I think the drag characteristics are so different at 30 MPH vs. 13 MPH that I am not sure it would hold up as a valid measurement of whether you are propped 'right'.

Give me some more insight on this.

More directly to the OP's question, I think the 1235 is the bomb. I do know that Acme is fond of using the same prop and adding a little more cup to it, which preserves the low end torque but also gives a couple MPH on the top end, thus getting the best of both worlds. I have a hunch that they might try to sell you that. Call Acme for sure. They usually would let you send it back if you think it doesn't perform well enough.

[EricU]

I was planning on calling ACME, but I just didn't have time last week. That is what I did last time and how I ended up with the 1235 that I have.

But I was kind of wondering about the 2079. I definitely need another as a spare as our lakes are low!! (Like that matters, I can hit things anywhere) and if I end up with another 1235, that is alright.

[shawndoggy]

I've never tried to get up to max RPM with my boat fully weighted. Interesting concept and I could see that as a measure of how much you are lugging the motor, but I think the drag characteristics are so different at 30 MPH vs. 13 MPH that I am not sure it would hold up as a valid measurement of whether you are propped 'right'.

Give me some more insight on this.

http://www.themalibucrew.com/forums/...l-your-engine/

[chpthril]

That is what I did last time and how I ended up with the 1235 that I have.

How is the 1235 performing currently? Has your ballast, size of crew, or lake elevation changed? I would answer those question, then based on those answers, you will have an idea of whether you need a more or less aggressive prop.

[EricU]

The current 1235 works fine. I have added more (potential) ballast, but last season was not able to dial in the wake for a number of reasons (ex. Blown fuse we couldn't find). I have system now working great (thanks CMS!) and have a bunch of lead on the way.

I need to order a prop this week because our main lake is two and a half hours away and I don't want a bent prop shutting down a weekend's worth of fun

[EricU]

I talked to ACME today and told them what I was running currently (1235) and that we had the potential now for more ballast.

He said to use either the 1615 or the 1873 and was suggesting that I go with the 1873.

Below are the different prop specs:

Part# -- Diam. Pitch ------ Cup
1235 ---14.50 14.250 --- 0.105
1615 ---14.50 13.750 --- 0.105
2079 ---14.50 12.000 --- 0.105
1873 --14.50 12.000 --- 0.150

Any ideas?

Chpthrill, can you get these props?

[Travism]

Could someone explain to me how the pitch and cup size work in relation to the top speed/bottom end torque of the boat ?

Sorry to Hijack

[chpthril]

@ Eric,

Yes

@ Travis.

Pitch on a boat is like rear end gears on a vehicle. Low gear and acceleration improves, engine RPM go up and top speed is decreased. Higher gear and acceleration slows, RPM are reduced and top speed increases.

Think of pitch of and RPM on each end of a teeter totter. Pitch goes up, RPM go down, go down in pitch, RPM go up. Top speed is tied to RPM. Pitch up = RPM down = top speed up. And pitch down = RPM up = top speed down. Tweaking the cup can improve the props performance, without the side effects of a pitch change

[EricU]

Mike, you pm box needs emptying!!! Trying to PM

[EricU]

Mike!!!! I need a prop!! I am just a couple of short weeks away from hitting the lake!!