cprperformance

Just wanted to update my findings on my prop/prop height testing. Had previously put in 2" spacers, removing 2 1/2 spacers (with B1's) which put my prop height at about 1 1/4 above the bottom of boat. Keep in mind this is a notched hull with XR's / sportmasters , no boxes. B1's definitely did not like this height, Too High. Put a vibration through boat and cracked blades! I was going to take spacers out but Jim from Hering said that the new props would probably like the higher dimension.
Last Oct. I finally got my Hering props, after endless emailing and calling! Props are 15 1/4 x 35 x 20deg. rake. Couldn't wait to get them on and go try them out. Upon getting them on and finally getting in for some testing with the new props I was very disappointed. Boat would not get on plane, had no mid range acceleration, and lost 7 mph. I knew that the spacers were going to have to come out anyways so I figured that I would remove them now and try the Herings again. After changing spacers back to my original ones (putting propshaft centerline back to 5/8 above the bottom of the boat) and getting back in the water for some testing I was totally amazed at the results. Boat would now effortlessly plane, had great midrange acceleration, and would run 122mph at 5300rpm, 3/4 -7/8 throttle. If somebody would have told me that 1/2" would make this much difference I would have said that you were nuts. Totally amazed!! However I am still faced with being on the rev limiters.
My thoughts are the props should have been a little larger diameter and a little bit more pitch.
Sent props back last Oct. and am faced with no props again, and can't get in touch with Jim Hering. Very tough individual to deal with!! Last I spoke to him, which was last Oct. he wanted to put cup in the blades. I don't think that cup is the answer, any thoughts?

headshothills

Interesting read.. Last year we picked up a 32SC with 525's, and I have been struggling to find the right setup. Original setup per Palini consisted of ITS, XR's, and -2 Shorties with stock Merc 34's with 5/8" diffuser cutoff. When we purchased the boat, it had 1" Spacers added, and labbed BBlades with a ton of cup. Those more expierienced have looked at the props and have said the 32's dont need the added cup and bow lift. When asking the previous owner what the deal was, he claimed the boat wouldnt plane, so they added drive spacers and labbed BBlades with a ton of cupping.

The boat rode like hell, literally had to drive everywhere will the drives damn near fully tucked to keep it from being a porpoise nightmare. The original labbed 34's from BBlades had the diffusers cut off then welded back on, but the previous owner hit something and broke a blade off, so this new set that came labbed is not as thinned out.. After pulling our hair out at the ride characteristics, I finally broke down and reached out to Jay, sent him pics of the drives, and X. He instructed me to get the spacers out, go back to stock merc 34's, and cut 5/8" of the diffuser off.

Last week we finally were able to test the characteristics with the spacers out. Although, I still dont have stock merc 34's and diffusers cut, I did have a set of Merc labbed 34's to at least get an idea of we were headed the right direction. The closest calc i could get for the current X is about 2 1/4".

The stock mer 34's blew out at 15 mph, tried everything to keep them hooked and just couldnt get on plane, I then left the motors at 4-4500rpm, and it rolled over in a short amount of time and then started to catch, obviously backing out.... The ride characteristic were night and day, the boat felt freed up like its never felt before, it didnt feel like it was stuck on the water. The porpoise was almost completely eliminated if any... Knowing this, we pulled the boat out of the water, and decided to put the labbed BBlades with a bunch of cup back on and see what characteristics it had. Sure enough, the porpoise was back. Although not as bad as it was with the spacer, it was an improvement over running these props with the spacers. Getting on plane was almost identical to what we saw with the merc labbed 34's, although the BBlades seemed to hold a tad longer, maybe 18-20mph, they still blew out, and the only way to roll it over was to let the motors sit at 4-4500rpm until it rolled then back out of it...

This brings me to my next point, I still plan to find a set of stock 34's and cut the diffuser, Im confident getting on plane will be the exact same as we see now, but I have also tried to search and stalk a lot of the Spectre boat and owners down to pick their brain about their setups. I cannot tell you how many 32SC's Ive seen with Hydromotive 5 blades, which really has me wondering if thats the way to go or not. Im still working towards Jay's recommended setup and was told to let him know what the boat was doing and he would advise which way to go next. The last guy I talked to with an 06 32SC, worked with BBlades and ended up with Hydromotive P5X 32's and the diffuser cut off....

Just thought i'd toss that out there if anyone has any input, didnt mean to hijack the thread, just wanted to share some of my exp's im having...

TDSracing

Sub'd in as good learning info. Mine is a full bottom that was original #6. Sad to say they vanished years before I got it. Now XR boat needing dialed in.