1 MAIDEN AMERICA

'02 38 Lightning, Staggered 575SCi, XR 1.5, 19.5" X dimension, props rotate in.

32P Bravo = 93MPH GPS @ 5350RPM and 4 broken props.
32P 15 5/8" Lab Maximus = 90MPH GPS @ 5200RPM, 5-7MPH midrange increase, no broken props.
Same Maximus + intercooler and pulley (5PSI boost, 5PSI water pressure from through hull and strainer) = 95.8MPH @ 5400RPM full of fuel and passengers. 150 gallons later (an hour or so ), MPH drops to 94 @ 5400RPM.

Goal:
Top speed and still be able to get on plane as I do now (a little tough, but everytime).

Questions:
I've read that too high an X can cause a loss of speed when lighter. I thought the rev limiter was set at 5350. With 30P props, I've hit it hard. With the 32P Maximus' I'm at 5400 RPM. I don't really feel anything but I see the tach twitch a little. Is the X a factor or the rev limiter?

I'm going to install stock heigth IMCO lowers unless I hear good advise otherwise (already did the uppers ). Should I install 1/2" spacers?

I have XR's with DWP. Water PSI is 20-25.
Will water pressure be a problem with the IMCO's?
Is it better to restrict the inlets or dump any excess pressure?

What do you think MPH will be with the IMCO's?

What prop should I use, Bravo, Maximus, Hydro, 4, 5 or 6 blade, diffuser or not, extention ring or not?
I've heard Merc changed the trailing edge on the Bravo prop. Do they still break? The labbed Maximus is way beefier than the stock Bravo. I've never seen a Hydro.

The boat is dry stored and thoroughly cleaned after every outing. Should I scuff the wetted surface? If so, parallel, perpendicular or randomly to the running surface? What grit and how much? What MPH gain might I see from this?

Has anyone tried piping the high pressure at the windshield to the front step? Did it help MPH? Any handling issues?

I run hard and try to maintain well. 175 hours in salt and, mostly fresh water in the Seattle area. I change the engine oil (Kendall 20-50) every 5-10 hours (sample tests every other change suggest I don't need to change the oil as often), drive oil every 25 hours (QS Gear Lube,looks good), blower and fuel pump oil every 50 hours (QS Gear Lube).
I have Red Line Heavy Shock oil for the next drive change. Any good?

When should I change the P/S, trim and tab oils?

Engines run perfect. When should I do a tune up and valve adjustment?
Engine puffs blue on start up sometimes, but no measurable oil consumption (even after 40 minutes at 5350RPM). A little extra valve oiling doesn't hurt.....does it? When should I pull the heads. When should the engines be pulled.

Thanks for any input.
Rob

FYI:
Had a yearly boat trip planned for Memorial day weekend '05, leaving Thursday before the weekend for 5 days in the San Juans. I was out on Lake Washingmachine the Saturday prior running fine. I slowed to go under I 90. When I just started getting back on plane, BAM, BAM, BAM, DAMN, KACHING$$. Spit the input out of a drive. Nothing a little overnight freight can't handle . Put the IMCO Extreme uppers on Wednesday night (they should have showed up Tuesday but someone had a problem, not IMCO or UPS, you know who you are), filled them and went to bed.
Woke up early Thursday morning, no drips, and left for the trip. We had an awesome time and great weather. The Swiftsure/shire (whatever/who cares, it's just sailboaters) race out of Victoria, and a bicycle race in downtown Victoria (great wipeout) were happening while we were there along with the other fun things there.
The straights were a bit rough, I had blisters on my throttle hand, and the sailboaters finished 12 hours ahead of schedule, soaked.
Watch the shower caps on those IMCO's, 1 bolt in the center of a round cap has led to 2 replacement caps. Safety wire them, IMCO.

chief fever

Maiden,can't help you much on yor set-up i've only got a 29' Fever but i lost my cap on my drive also good idea to safety wire it,thank's for the tip and good luck!!

CayFomula

Maiden America,

Have you ever tried another motor oil? I have had some really bad experiences with Kendal (a couple of years back) and I wouldn't use it to lubricate a saw. Based on my experience I wouldn't be surprised if that is why you lost speed when it was light after running and the puff of blue smoke.

1 MAIDEN AMERICA

The loss of speed only occurs when light. The blue puffs happen here and there after hot soaks. The longer the soak, the more likely to puff. Not always though. Air and water conditions always play a roll in top speed. The speeds I listed are the best top speeds I ever attain. Usually 90% of the time on Lake Washington.
One time I launched the boat, warmed it up, did a full throttle pass at 92MPH max, came back to the dock and changed the oil. Warmed her up and ran full throttle again, 95.8MPH. Kendall 20-50.
I've been running it for years in my boats and hot rods without issues. Knock on teak. I wish it was still green though.
Some of my friends have been switching to Merc/QS oil. They like it. Any good?

CayFomula

The first incident I had with Kendal Motor oil was when I had a mechanic change the oil in compressor for a jackhammer which had been running fine. I got the manual and gave the mechanic the specific oil requirements and left him to change the oil. Shortly after he finished I got a call from the operator to say they had just started using the compressor but thinks it mashed up. They had started it, warmed it up and within less than a minute of starting to use the hammer the temperature alarm had come on then it shut down spitting oil out the airfilter. After a few check I started it up again and it did exactly as the guy had said.

I had the mechanic show me the containers and all the specs were right, after discussing with my boss we decided that the only thing we had done was change the oil and we didn't have any prior experience with Kendal so we instructed the mechanic to replace the oil with Valvoline which we had been using. He replaced the oil and the compressor worked perfectly.

At the time we also had multiple new generators that had been giving trouble particularly when load was applied guess what type of oil we were using in them. Well after the abover experience I decided to try replacing the oil with Valvoline and sure enough all but one of them started to work perfectly, the other had apparantly been permanently damaged.

While I have had other bad experiences with it which I wont bother to articulate I am sure you can see why I don't have any faith in Kendal Motor oil.

1 MAIDEN AMERICA

Cracked a 32 Maximus. Repaired it. Now that engine runs bad. See general Q&A forum please. Help is appreciated.
Thanks, Rob

1 MAIDEN AMERICA

Rotors are bent. Can I get parts? Oil reservoir in rear, dipstick in front style blower.

FeverMike

Wow, that's a lot of questions! My friends, racers and I always use Mobil 1. Tested to be the best...period...end of story.You are wasting money by changing the oil too often...give it a break and enjoy boating...your working to dang hard. trim and drive pumps oils can go for years, don't worry about them. If you have trouble getting on plan it's either the props or most likely the X is too high. That twitch in the tack at 5400 is the rev limit.

nolimits

I have an 03 38 Lightning with 575, supper chillers, 5 lbs boost, Imco shorties, ITS extension, fairing instead of the windshield, 32p Labbed Hydo 5 blades. I was told by the original owner that she has a higher X dimenssion than was typical for the 38's of that year. The boat build was overseen by Reggie and originally released with Sportmasters. It ran 103.5 from the factory. The shorties were added and props were tweeked and the prev owner saw 106.1 on a lake. I saw 105.3 on the test drive and now that I own it, we have seen 108.1. These are all GPS speeds validated through two GPS each time.

Since it now lives on salt, we added a screen for sea grass. Spent most of the summer chasing a port engine that gets too hot after 90 + runs. We enlarged the screen hole which helps alot. We just added a 1" spacer to the Imco's and now it awaits test. Busy week ahead, next weekend for sure.

Snapped a vertical shaft in the Imco and rebuilt an upper bravo. The boats a hoot and I love the tail of water coming out the back. Anyway, aside from props and a year, perhaps different X dimension ( all of this might be a big difference) we are very similar. Seems to me you should be running faster. I am running an 11 percent slip at 5400 rpm. You are slipping alot more than me if you are running 95 at 5400 with a 32p prop. Then again, my drive is a 1.35 ratio and if you are at a 1.5 we are about the same.
Check out this sight for prop slip: http://www.rbbi.com/folders/prop/propcalc.htm

But then you should be hitting the limiter, and maybe you need to try a 34 pitch if you are really running a 1.5 ratio....
I would call hydromotive to start. Hope this helps... Good luck.

1 MAIDEN AMERICA

Thanks for the post. I am 1.5. Since I broke the prop I'll go for the 32 Hydros. First I have to fix the blown head gasket between 3, 5 and 7. 188 hours. And the blower. After that I'll take the other engine apart and do the same...while it still runs properly. Love the twins. I don't have ITS so I'll run standard IMCO's. Do you have any water pressure problems?

Rob