Props for 46

[splashandburn]

What props are you guys running on the 46's? I'm running stock 28P - 4 blades but not getting the speed that others say they're getting. Boat's an '03 with twin 500 EFI's with ProChargers running 5 psi boost and only seeing 4600 rpm and 66 mph. Any suggestions?

[Ratickle]

You're right, that seems very low for your performance package. What is the HP with that amount of boost?

[Cruz-N-Thunder]

2001 430EC with 575sci dynoed at 725hp, stock 32p bravo one, 85mph at 5300rpm. Seems like u have something wrong. When mine were stock and tired ran 28p bravo one at 5200 at 73mph. I am assuming you are a 1.5 ratio. If somehow a 1.3 ratio would explain how over propped you are. Otherwise something wrong. Tabs up and drives around 7?

[splashandburn]

You're right, that seems very low for your performance package. What is the HP with that amount of boost?

Not sure of HP but I'm guessing its gotta be around 600 HP or so . . .

[splashandburn]

2001 430EC with 575sci dynoed at 725hp, stock 32p bravo one, 85mph at 5300rpm. Seems like u have something wrong. When mine were stock and tired ran 28p bravo one at 5200 at 73mph. I am assuming you are a 1.5 ratio. If somehow a 1.3 ratio would explain how over propped you are. Otherwise something wrong. Tabs up and drives around 7?

Yes these are 1.5 ratio drives with tabs up and fully trimmed. The drives do have 2" spacers on them though which puts them pretty deep in the water - think that could explain why I'm not turning these 28's at a higher rpm?

[Serious News]

Hot Boat magazine did a test in July of 2003 on a twin engine 46 EC with 500EFI's stock. It ran "a consistent solid 70-mile-per-hour top end". In June of 1999 they tested a SC with the same power and it ran 73 with box-stock 26-inch Merc 4 blades and cruised at 60-mph at 4000 rpm.

[CarbonKevlar]

Check your bottom with a straight edge ,from the transom forward down the deadrise ,they have a tendency to prerelease ,you are looking for negatives (hooks) in the bottom. The straight edge should be 8' to 12' long.

[endeavor1]

My 43 with 500s and pro chargers is just took off would run a lot better than 66. I spun 32pitch bravo ones. Dyno sheet said over 750hp. M3sc @ 5lbs rinning a 1.5 bravo xr

[splashandburn]

Tried a set of 28P props yesterday that were labbed by Merc and spun those @ 5000 rpm but got exactly the same 66 mph. Not sure what to try next . .

[endeavor1]

That's 25% slip. Way to high. Is your speed gps? With 17% slip you would have been at 73. It sounds like you have a slip problem or your motors aren't making power. 5lbs on stock 500s should make 650 any day IMO and run upper 70s maybe 80.

[Ratickle]

Carbon Kevlar is right, you need to check for a hook in the bottom of the boat. Plus, if someone has added 2" spacers to the drives after it left the factory, I can't think of a good reason. Maybe they were running bad 3 blade props and now have switched to 4 blades, or the bottom is hooked (but that should make it plane off easier). Here's an outboard schematic, but basically you can check drive height by taping something straight to the bottom of the keel extending back alongside the drives, and then tape another straight piece onto the side of one of the drives. Check the distance between the two when they are accurately aligned. Then, let us know, and maybe even take a picture of your setup.


http://i730.photobucket.com/albums/ww310/ptrose/Misc%20and%20Personal%20Boats/DriveHeight.jpg (http://s730.photobucket.com/user/ptrose/media/Misc%20and%20Personal%20Boats/DriveHeight.jpg.html)

[Ratickle]

I should have said as close to the drive as possible, not the bottom of the keel. Even better would be to have the one taped to the bottom of the boat stop in front of the drive and the one taped to the side of the drive at propshaft centerline extend forward of the drive to get the accurate measurement of drive height.

[splashandburn]

I should have said as close to the drive as possible, not the bottom of the keel. Even better would be to have the one taped to the bottom of the boat stop in front of the drive and the one taped to the side of the drive at propshaft centerline extend forward of the drive to get the accurate measurement of drive height.

OK thanks I'll check all this out once I get the boat home. I did run a set of stock 26p props this weekend and boat ran much better - 5300 rpm and 71 mph. Seems like alot of rpm gain from a stock 28 @ 4600 to a stock 26 @ 5300 though?

[endeavor1]

OK thanks I'll check all this out once I get the boat home. I did run a set of stock 26p props this weekend and boat ran much better - 5300 rpm and 71 mph. Seems like alot of rpm gain from a stock 28 @ 4600 to a stock 26 @ 5300 though?

Something is wrong if you are only seeing 71 on blown 500efi. Are you sure your engines are making boost? Sounds like they are running weak if so. Timing? Fuel pressure?? What's the gauges telling you?

Call me if you want and I'll gladly share with you how mine ran and indicated with M3SCs on it or my 46 with 700s.
870 623 434five

Chris

[Ratickle]

If the engines are stock except for the boost, their peak RPM should be around 5200. Before you were under the max hp rpm range, so once you got to the optimum rpm for the configuration of the engine, it could have made that much difference. You'd be shocked at the difference a quarter of an inch will make in one of our race boats.

I still think you are a little low on speed for that package. I'll be really interested in the shape of the bottom and the depth of the drives.

Also, unless a prop has truly been blueprinted by a reputable prop shop, you really have no idea of how good they actually are.

[splashandburn]

I still think you are a little low on speed for that package. I'll be really interested in the shape of the bottom and the depth of the drives.

I plan to get the measurements in another week once I get the boat back home. I know the drives must be deeper than normal since its running with the 2" spacers on them. I'm planning to take those off and see what that does for the performance numbers.

[splashandburn]

Something is wrong if you are only seeing 71 on blown 500efi. Are you sure your engines are making boost? Sounds like they are running weak if so. Timing? Fuel pressure?? What's the gauges telling you?


Not sure of timing but fuel pressure is 40 psi and boost gauges are showing 5 lbs of boost @ WOT.

[endeavor1]

Get rid of the spacers. That's gonna be your problem I bet. I remember talking to the shop that repoed/mechanics lei end your boat from the previous owner and they stated the previous owner had those added to try and bury the drives and keep them from breaking. I misunderstood you and thought the boat already had those removed.

Good luck and let us know how it goes.

[splashandburn]

So whats the thought on burying the drives? Isn't that going to put even more stress on them?

[Coolerman]

2" spacers on that boat is a no-go...... The 2" spacer would keep the prop from spinning up if you are jumping cruiser wakes and didn't want to throttle it.

The boat will probably not only go faster without them, but probably handle much better to. I would even consider -2 shorties and 5 blades.

[endeavor1]

Sax is right. -2 drives and 5 blades on a 46. My 02 was night and day different 4 blade to 5 blade and my 43 was same with /shorter drives. John P kept thinking I was crazy till he swapped out to -2 on his 46 and has never looked back since.

[Coolerman]

Who the phuck is Sax? LOL

[endeavor1]

Who the phuck is Sax? LOL

A really 6 awesome guy. Much better than the phuck head who calls himself cooler bitch

[Ratickle]

Any luck?

[splashandburn]

I pulled the spacers off and actually lost speed all around (mid range and top end). I haven't had a chance to get any measurements as to drive height yet but I will in the next couple weeks. I'll post what I find.

[Coolerman]

Any luck without spacers and 5 blades?

[endeavor1]

If that's the case, I'd seriously be questioning the HP your motors are making. Leak downs are in order IMO

[endeavor1]

Pressure check the inner coolers to ensure you aren't loosing boost there.

[splashandburn]

If that's the case, I'd seriously be questioning the HP your motors are making. Leak downs are in order IMO

I was planning on doing that this winter anyway just to see what things looked like. I'll pressure test the inter coolers too while I'm at it.

[endeavor1]

I was planning on doing that this winter anyway just to see what things looked like. I'll pressure test the inter coolers too while I'm at it.

Hope it's something simple for you to fix rather than a big mess. I remember those motors were torn down then being put back together when it was first listed for sale.

[splashandburn]

Hope it's something simple for you to fix rather than a big mess. I remember those motors were torn down then being put back together when it was first listed for sale.

Not sure. Boat runs great and I've put 120 hours on the motors so they couldn't have done too bad a job with them.

[endeavor1]

Not sure. Boat runs great and I've put 120 hours on the motors so they couldn't have done too bad a job with them.

Agreed, I doubt the engine itself is to blame but rather the procharger setup

[splashandburn]

Yah that's what I was thinking too although not sure what could be the issue. I'm making 5 lbs boost according to my gauges so where could that be going?

[endeavor1]

Where is pressure reading taken? Mine being carbed 500s was in the intake under the carb. 5lbs is what mine ran also. I spun 32s though. My 43 shouldnt differ that much if any from your 46. It blows me away that things got worse when you pulled the spacers. I run 26s now on NA motors and run 70 at least all the time loaded. I'm perplexed with that boat but I still like the paint job!! I'd try the following to see if anything stands out.

Compression test

Verify drive ratio is 1.5

Get a long straight edge and check hull for hook and drive height

If possible, weigh boat and trailer to make sure it isn't soggy.

[splashandburn]

Planning to do leak down test and dyno this winter. That should tell me alot.

[endeavor1]

^^^agreed

[splashandburn]

So I pressure tested one of the intercoolers today and it has a leak on the water side. Very small pinhole inside the heat exchanger. Goes from 20 psi to 10 in just over an hour.

[endeavor1]

Hmmm

[Ratickle]

Would that make that much of a difference in power?

[endeavor1]

Would that make that much of a difference in power?

Called Sax and he stated that the variance would lead to putting out the flame in the fire.... He's the Sax so I'd say he's qualified

[splashandburn]

I don't buy that this could be at all power robbing. This has to be a pinhole and under such low pressure I can't be putting that much on the fire.

[Ratickle]

Do you notice a major throttle position difference between the two engines?

[endeavor1]

I'm curious on what they make on the Dyno ? Ed Champion said 700 to me when the boat was listed for sale

[Ratickle]

Everything else being said, I'm still thinking there is an issue with the setup or bottom. The huge differences in speed with 2" extension in or out, and the two different prop sets, makes me think there has to be a trim, bottom, drive lineup, prop configuration, etc issue as the main problem. He's not even getting the same speeds as the tests when the test boats had stock engines.....

[Coolerman]

The intercooler could be putting out the fire, but not necessarily.

You checked everything with your ignition as well? Timing? We've had a rev limiter go bad in the MSD ignitions before. It was very tough to read because the motor with the good ignition didn't have enough power at the time to pull that many more rr's than the one with the bad ignition.

[Ratickle]

If the pinhole were hurting that much you don't think the throttle positions would be drastically different when in sync?

[splashandburn]

Throttle positions are identical. Gonna pull the other cooler Sunday and pressure test that one too.

[splashandburn]

OK so the second intercooler is leaking even worse. I put 10 psi on the water side and it leaks out almost immediately. Motor is out so gonna do a leakdown on that next week and see what shows up. I have 2 new intercoolers from Frozen Boost that I'm gonna use to dyno.

[endeavor1]

OK so the second intercooler is leaking even worse. I put 10 psi on the water side and it leaks out almost immediately. Motor is out so gonna do a leakdown on that next week and see what shows up. I have 2 new intercoolers from Frozen Boost that I'm gonna use to dyno.

Good deal. Glad you are finding something to point you in the correct direction

[Ratickle]

I guess that's good news, kinda.....


Don't forget to check the bottom and the drive height though. You would be shocked at how much speed is scrubbed by very slight indent area.

[offshoreexcursion]

I had very good luck with my Procharged 500EFI's. Hang in there and you will get all the kinks worked out.

There might be more then one problem at a time also

[splashandburn]

Ran an 8 foot straightedge all along the bottom today and there's no hook. Its completely flat all the way back. I'll get drive height later this week. Doing leakdown this week too.

[endeavor1]

Cool

[Ratickle]

That is a good thing. Black Thunder never had the big problems some mfg's did with pulling the hulls too quickly from the mold, but you never know.

[splashandburn]

So here's another update. Pulled the 1st motor and did leak down and compression test. Ends up there is 150 psi in 2 cylinders, 125 in 2 others and only 110-115 in the other 4, so I'm guessing that's my issue. Didn't bother to dyno after finding these results. Pulled the 2nd motor and that ones in the shop now too. While they're out we're gonna do complete rebuilds - 540's. It'll be interesting to see how these were actually "rebuilt" before I bought it or if they were done at all. We'll know more in the next week or so.

[Ratickle]

540's with the blowers? Should be a strong runner then.

[endeavor1]

Any updates to your engine builds?

[splashandburn]

Any updates to your engine builds?

Parts are all in an being put together now. Going to dyno once they're done and should have them back in a couple weeks. Can't wait to run them!

[endeavor1]

Parts are all in an being put together now. Going to dyno once they're done and should have them back in a couple weeks. Can't wait to run them!

Curious what cams you were running? When dynod they made 760hp @5lbs on Dyno headers and no accy. I just pulled mine out to go to a cam more favorable for NA.

Compression readings were 183-194

The cams I pulled were:

270/276 adv.
.510 lift
110 LSA
Comp grind HR270

[splashandburn]

Pretty sure the cams were just stock cams. I dont think much was done to these motors previously. They were in pretty bad shape.

[endeavor1]

Pretty sure the cams were just stock cams. I dont think much was done to these motors previously. They were in pretty bad shape.

How many hours have you put on it? Ed Champion told me when it was for sale that the power was being rebuilt and would be fresh. At least it will be right now!!

[splashandburn]

I put 100 hours on it. They might have been "rebuilt" but not very well. There were mismatched pistons, a chunk missing out of one block and the oil pump pick up was only held on with a piece of wire on one motor. I'm guessing whoever built them reused the same rings cause the compression shouldn't have dropped off as far as it did with just 100 hours. New motor build dynos @ 640 hp before the Prochargers so we'll see what they do with the Prochargers. Should be dynoed later this month.

[endeavor1]

I put 100 hours on it. They might have been "rebuilt" but not very well. There were mismatched pistons, a chunk missing out of one block and the oil pump pick up was only held on with a piece of wire on one motor. I'm guessing whoever built them reused the same rings cause the compression shouldn't have dropped off as far as it did with just 100 hours. New motor build dynos @ 640 hp before the Prochargers so we'll see what they do with the Prochargers. Should be dynoed later this month.

Glad to hear about those new mills!!!

[Ratickle]

So a complete engine rebuild with existing rings. Must be a new Obamacare engine shop.......

[endeavor1]

First off , Sax-Cooler is on a date with a thick thigh hottie. I've got a set of 088 head 555cid motors headed to the dyno. Pro/System carbs among some goodies from derebery in TX. Not gonna out run a skater but may it drink one or at least cut it in half

[Ratickle]

Naturally aspirated?

[Coolerman]

First off , Sax-Cooler is on a date with a thick thigh hottie. I've got a set of 088 head 555cid motors headed to the dyno. Pro/System carbs among some goodies from derebery in TX. Not gonna out run a skater but may it drink one or at least cut it in half

OMG, she was hot, but not hot (when I turned the lights on). Picks nsfw