TomZ

iTrader: (2)

Well, Jeannette had surgery this afternoon and is now here at home resting comfortably. She had to have the never-ending miscarriage forced to end, and they'll need to run everything through pathology to confirm some things. Basically, her problem is what's called a "molar pregnancy" which can lead to cancer-like cell growth that spreads from the uterus to everywhere else. So, not only has it taken us over three years to be able to properly conceive (after me going through surgery and a very rough recovery period myself), but now we have not only a miscarriage, but a potentially life-threating complication. Fortunately, the doctor said that the tissue did not "look" like that of a full molar pregnancy, but she couldn't rule out a full or partial wihtout tests. Needless to say... I'm praying for it to not be either. Man... what a day. Thanks for the well wishes.

Jeff,

I think Comp is going to recommend a custom grind for my setup (they did before when I ran the 274H by them... same numbers basically with a change in the LSA to 112*). I know that you love those cams. Hmmm... I really don't know what to say (too much going on in my head at the moment). I'm having trouble trying to figure out how this boat should perform. The hull is a deep-vee (rather conservative toward the rear but still a vee, not a a modified vee) and I figure that the weight is somewhere in the 4800 pounds range with full fuel and people (let's say Jeannette and I). I'm running a 1.50 Alpha drive and I'm pushing at least double the power that the old 355 made (seeing as how it was whooped and all). I'm not doing any better so far that the old motor did. Aside from the cam and maybe some minor tuning issues, what am I missing here? I've read up on some hull features and such and feel that I'm "ok" in those respects. Outside of doing some cleaning and waxing of the bottom, and working on the trim, what else am I missing here? Is the cam selection hurting my torque enough where I can't spin that 21P faster than the 4200-4600 RPM that I already achieved? I know that there is some serious speed lokced up in here somewhere... I'd just love to figure out how to pick the lock free!

Thanks!

mxz800

Tom best wishes with the medical problems, hope it turns out for the best soon!!!!



as for waxing the bottom might want to do a search on that seems it sometimes hurts way more than it helps. some even go to the point of sanding the bottom to introduce air and free the hull up rather than the wax making the hull grab the water.



Rob

jr

I'm hoping for the best for your wife Tom. Like I said hang in there.


Remember that we have two different boats. I have a twin engine hull that weights as much as yours. I'm spinning 22 hydromotives, but need bigger, but my two drives share the load. So far my top end is approx. 65 But I have twice the HP and at the same weight.

Think about a smaller carb. Remember what George said. Torque comes from velocity of the mix. A 650 will boost your velocity. I'm also running a 1 inch spacer that was port mached to the carb, as was the manifold. Which all smooth the mixture stream.

50 is still pretty good in a 5000 lb. single boat. How would it run with the old 350?

TomZ

iTrader: (2)

Wow, didn't know that a 26ft Wellcraft was so light! I really have no idea about the weight of the boat other than the fact that NADA lists the "net weight" of the boat at 3415 lbs. I'm assuming that, a) the weight is the boat outfitted with the engine and drive, and the different accessories that were "standard" on the boat, and b) the net weight does not include fuel, life saving equipment, food, occupants, and any water that may be in the hull (it's been pretty dry lately and with the heat I think I'm pretty dry in there). If the posted net weight includes fuel then knock off a good 500 pounds or so. Ya know, I may just go and have the boat and trailer weighed and then subtract the trailer weight to get the boat weight.

The 355 was pushing the boat to about 40 or so with the crap heads and Isky cam and then to about 50 (maybe 48, 49) with the Vortec heads and Comp cam. Still, the motor was a DOG due to the fact that it was wore out and consuming oil. So.... something is not right here.

Also, just looked up the "net weight" of the Nova II 26 and the weight comes in at 5200 pounds. So before you figure in weight of fuel, etc., the extra horsepower is still trying to carry an additional 1800 pounds in comparison to my boat's net weight. which equates into about a 2 lbs per hp difference between the two boats with the odds in your favor (net weight of each boat divided by approx. HP at top end... I figured 800 for yours and 400 for mine... granted, I still have not seen the top-end on mine, still about 500 RPM shy if not more). Should that equate to a difference of at least 15 MPH (being that your engines are still not into the secondaries)? That just doesn't quite compute, don't you agree?

olysan

Hey Tom,

Best of luck to you and your wife.

I think that my boat is a pretty good comparison. I have a 1989 Mach 1, MV 2450 CC Magnum. I dug out the old literature, and here are the specs:

Centerline Length : 23'8" I'm not sure but I think this includes the swim platform.
Beam : 96"
Weight (7.4/Bravo): 4025 lbs
Deadrise : 22 degrees

I haven't been out this summer, but last year I was running a consistent 53-54 on gps at 5000 rpm.

I'm running the same cams as jr in my 406. I had it dyno'd last year before I put it back in the boat 'm going to try and attach a scan of the dyno sheet. Max power was 360 @ 5000.

I think that you're making more power than that with your cam. I'd give that 21 another try now that you've got some of the bugs worked out with the engine. This is just gut feel, but I would think if you can get on plane then you should have plenty of torque to get up into the power band of your engine.

The only other thing you might want to think about is are those heads to much for your the rest of your systems? I'm running stock Vortecs. I know yours are ported and use bigger valves, but if you don't have a good breathing flame arrestor, and free flowing exhaust, you could be having some problems.

I'll try and post a pick of my boat below for your reference.

Mike

olysan

pic from 1989 literature.

TomZ

iTrader: (2)

Mike, Your pic didn't make it.

I guess I need to find out exactly what the boat weighs to be able to accurately predict the top end. My boat is slightly smaller than yours and that makes sense when looking at the posted weights of the boats.

As for the heads... they have not been "over ported" just opened up some (especailly on the exhaust side). The guy who ported the heads does the same work for guys running Vortec-based motors in IMCA racing (the engines are for the most part stock to keep the fields even). So, I have the big valves, blah, blah, blah which basically turned the heads into iron versions of the Fast-Burn aluminum head, flow-wise. I think they work OK.

I'm going to try out the 21P again this weekend to see what happens. But I'm still interested in finding an explanation to the above info that I posted regarding the comparison between my configuration and jr's.

And another thing... watching my boat from the water\ (tubing, sidelines, etc.) I noticed that a lot of the hull is still in the water even planing. maybe I need a way of getting the stern out of the water more.

Thoughts... ideas?

Thanks!

jr

Mike, what are you running for an intake?

Tom, I looked up an old spec sheet on my boat. It goes 5200 lbs, plus 108 gallons, plus 200 lbs of me, and misc. crap. So I'd figure 6300 easy. Now also figure in the rolled on bottom paint. Now if that isn't like trying to drag a non slip surface through the water I don't know what is.

After looking at Mikes numbers, I feel I'm pretty accurate around 425 HP probably give or take 15.

turbo2256

Do you know what the heads flow at different valve lifts. Hope the wifes better by now.

olysan

edelbrock performer rpm - vortec intake
Aluminium