280 Drive upgrades- 2" shorty?
 

Has anybody played with their x dimension either lowering or raising it on their 280 Silencer?
Its too cold to go boating now so I am planning to do some upgrades this winter.
I was thinking of putting on a 2" shorty of some kind.
Any input would be great!
Thanks,
Mike

Anybody??????????

Had a 280 that I just traded 2 months ago for a 340 Vyper. Loved the Silencer but the bigger boat is awsome. I never toyed with the X dimension but in my driving experience with the boat (I owned it 8 years) I believe the drive was height was just right and my Bravo had the 2" spacer in it. I might be worried about your prop blowing out if it were higher. I am not an expert, just my .02 for whatever its worth. Good luck.

Hi

Im also intrested to add 2" spacer on my drive. Is it worth it ? and what benefits i can get with it?

With a 2" spacer that would put the prop lower in the water right??

Yes it will.

Would there be a limit as to how high the prop could be raised without hurting getting on plane?
It would be fun to throw a roost like a #6 drive would.

I "think" the X also depends on which engine is installed in the boat.If someone knows for sure,I'd like to know.

my 2000 w/502 has a 1" spacer, the previous owner put it in and picked up a couple mph, I think he was blowing out all the time also. sounds like they went too aggressive on some of the X dimensions

Not Right, does the boat blow out just as it rolls onto plane or is it everywhere?
I will take the prop off the boat tonight and measure the prop shaft to the bottom of the boat and see where it sits.

Verbi69,
I have a 2000 280 silencer with a 502. It came with a 24 p bravo I. My boat will blow out a little bit just as it rolls onto plane. (It does that only as it coming onto plane, never any time else.)
I believe the X dimension is pretty high on the 280's. I was going to try a 5 blade some time, or may eventually try a 1" spacer. For now, I like the way it runs. I am used to the slight blow out on take off and it is not a problem.

hey guys theres two ways to measure 1 is make sure your drive is level with the bottom of the boat then check from bottom to prop shaft deep drives are ones 6'' or deeper 7 or 8''. 4 1/2'' to 5 1/2'' middle and 4'' to 1'' high side. also your x is measured by center of gimbal pins are to bottom newer boats with steps seem to be 17'' or higher or if you have a box or notched transom. my baja hit a wall at 76mph for years then I but a 2'' shortie on and picked up 8mph with a carb change too. so figure 4 or 5 with shortie. boat ran flatter in rough to and mid 80s. so if you guys post some numbers I can give you some info on other boats that I know the heights of. my new ride is a SABER 28 WITH A KONRAD drive going on with a box. factory was around 7 5/8 or 8'' it was slow then the owner picked up 2 or 3mph with a 2'' shortie. since I am running a box and the performance lower we are starting with a 3'' high or 17 1/2'' X. with big power hope to break a 100.

when your getting on plane are you trimed all the way down and put your tabs down? if you nail it and send the nose to the moon you will slip any boat plus put a lot of strain on your drive. my boat was 7'' deep on the prop shaft and I blew a prop and also the coupler the 1st year I owned the boat:grinser010: with 330hp from not using my k planes trimming in and nailing the throttle:lolhit:. I mostly throttle it up to 3000rpm and as it falls over on plane pull back and throttle it again with a stock b1 drive for 10yrs with 600hp plus and before with 400hp plus for 4 yrs, then went to a newer b1 with a shortie for 2 yrs until it was stolen:eek:. if I can help anyone pm or post back here . and with the spacers you are putting the drive deeper = less performance mostly. so if your cavitating a lot it could be the prop ,there are different 4 blades out there some bow lifting and others transom lifting which will give you cavitation on the wrong hull.

Air Time I could only wish to run 100. Good luck and have fun with that!!
Murf, my 280 blows out exactly like yours...I have to back off the throttle for a second as it rolls over....then throttle up again as it flattens...its the only time I blow out.
What I would like to do is add an extension box to raise the prop shaft height and hopefully pick up some speed....
My boat has a single stepped hull with the notched transom.
Thanks guys,
Mike.

I am super gentle on my boat getting on plane. It ALWAYS blows out as it starts to roll over. It goes again but I think it is always slipping. I can literally rev up the engine while cruising with minimal increase in speed. I feel it is always slipping. 3500 rpm is 40 mph for me. Top speed is 74 gps at 4900. (496ho with 3.5 boost procharger 28 bravo 1 4 blade) I am thinking a spacer will get the prop in cleaner water and help with cruise speed and top end. I am trying to find a couple different sizes to borrow before I spend $400 a crack to try.

Hey Verbie, what kind of speeds are you seeing with your power? Top end and cruising?

SpecialK, if memory serves me correct I think my cruising speed is similar to yours give or take a couple hundred rpm.
I'm running a BBlades labbed 26 Bravo 1 with maximum cup, spinning 5250-5300 rpm ( yes re-mapped ecu).
With this prop, 4 adults and full fuel I have seen 74.0 mph on the gps, the speedo at that speed is only 1 mph off.
Most of the time it is a constant 73 ish.
This spring I will try a labbed 28 with less cup as my 26 to keep the rpm up to where I need to be. Also in the plan is to get rid of the stock exhaust and run headers. I was thinking with an extension box there might be additional mph to be gained as well.

Oh and the only time the boat will blow out is as it rolls over....does not matter if the tabs are down or not.
I can hammer the throttle from a dead stop without blowing out the prop....as the boat rolls onto plane then it blows out...I simply back out of the throttle for a second then I can give it the full throttle again ....and off to the races we go.

I have a labbed 26 bravo so I think you guys with 100-150 more hp are way under propped, you can borrow props from any of the guys that sell them.

I dont have any blow out issues, I was saying the previous owner had issues before the 1" spacer.

I have tried about 5 different props. I could not turn any rpm with a 30. I did not have access to a five blade. It will never be the fastest around, but I was trying to pick up some cruising mph to help with the gallons per minute burned. Of course I would love to see upper 70 mph range even though you can never go out and do that on lake michigan with a 28 footer on most days.

Trying to find the right prop can take some time and requires patience thats for sure.
Not Right, maximum rpm plays an important role in prop pitch selection.
I was able to keep the 26 Bravo 1 I was running before the increase in hp because the engine went from max rpm of 4900 to the now new max rpm of 5350. I also had alot of cup added to the prop which brings down rpm.
That being said I think a labbed Bravo 1 28 pitch with little to no cup would be a good fit and keep me in the rpm range and give me more mph.
Thanks my thinking anyway....

ohhey can you measure your prop shaft to bottom of keel and post it. what speed did you have at 4000rpm also. I might have a idea for thr both of you. with a box if your two high that will get you deeper. if your deep or so so a imco 3'' raised box helps. there is a 25ol with 525 merc would run 74gps with a prop change to a 28b1 and imco 3'' raised box went 81mph with a merc 600 same box and 1'' shortie was running gps87 to 89.I take it your prop is stock, post your height and I could give you advise on either needing a box which one or your perfect and need brett to adjust your prop your rpms are low for your set up you could pick up speed with one of the following height is fine work prop, height is low go to box with raised3'' orprop is high go to box or 5 blades, like Isaid my boat with standard height would rev if I did not pull back with 3 and 4 blades. so if you to give me the numbers I will try and help thats what oso is about. the b1 prop is a bow lifting which is good for you guys.

Thanks for the info Air Time. Not sure when I will get around to measuring, it is tucked away for winter. Dont forget the 280 PQ is a stepped hull. A box would be getting a little carried away for the kind of boating I do. It would start with the box, then need k-planes then upgrade drive then run a little more boost...etc. I love the boat but toying the idea of a 30 something foot with twins. However, 5 mph extra with my present package would get me thinking.

I'll get my lazy but off the couch and get in the garage hopefully tonight to do the measuring....I keep forgetting.
If there is more mph left in the boat to be had with some drive work I'm in for that...it is probably cheaper then putting in more hp. We love the boat...just wanna go faster!!
Thanks for all the input....I really appreciate it!!
Thanks,
Mike.

stepped is goodmost of the time have a higher x.once you guys post the height I will look overwhat I have on stepped hulls for height. with a box k planes and hyd steering is a must. jon on here has a duel set up, and I have a single set for sale.but 1st lets see where the props are. forshaft height

i just went and measured mine, best I can tell it's 4.5" from btm to cl of prop shaft, keep in mine I have a 1" spacer.

I just went and measured my drive height and I am at 5 1/2" as best I could tell.
Set up is a 496 ho with Bravo X drive.
I also measured the X dimension- centre of gimbal ring to centre of prop shaft and it is at 22" as best I could tell there also.
I appreciate everyone taking their time to help out!
Thanks,
Mike.

Air Time, what do you have for hydraulic steering that is for sale??

Looks like I am at about 5 1/2 inches. Should the prop shaft be level when measuring or drive all of the way down. I measured all of the way down which does not seem right. I didnt feel like connecting batteries to raise drive to make shaft level. Also, I am assuming we should measure from back of the boat and not the lowest part which is the front section of the step.
The notched section at the transom is 6".

mine wasnt perfectly level so I may be closer to 5.5", it was about 30 degress out so I didnt spend too much time out there.

Sounds like we have the same setup.

Or you could buy my '01 280.Already has full hyd steering and runs 80-81 gps and not have to do all that work! lol Bob

hey that measure you took is wrong, you go from gimbal center which you did to keel bottom, not prop shaft all bravos are the same from gimbal to prop shaft just think for a second. unless they have a spacer or shortie. its the hull and drive. so you are at 17 1/2 which normal. steering is ziegler single ram new and imco twin minus drive plate used

level and you have a notch to, could someone post a pic that changes stuff sometimes.

My bad, I had forgotten to subtract the drive depth.
I;ll head to the garage and grab a pic.
Thanks.

Her you go.....
Bob stop rubbing salt in the wound..lol
:coolcowboy:

Darn, how the heck do you load a pic????

Verbi,Sorry,just trying to sell my beautiful PQ.I love it,just want a two engine 35 before I'm too old to enjoy it!

I hear ya Bob....I think I'm ready for twins too!!
A 30 ft Revenge with the same graphic package would be really nice!!

I just moved to Slidell(off Lake Ponchatrain)and this Summer I want to make a few trips to the Gulf Coast.Like my buddies say...."if it's too big to paddle,ya need two engines!"

I had twins but got out of boating for a while and wanted to jump around to some rivers and lakes just to go boating again so I picked up the 280. As much as I like the 280, I am like the rest of you that would jump up to a twin mid 30 footer if the right deal popped up. I almost bought a revenge loaded with options with the same graphics as Verbie. 496s super low hours but the seller kept raising the price. Had my interest at 50k and lost my interest at 65k.