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View Full Version : Shazaam!!!!! She Runs!!



sosmerc
05-20-2001, 08:29 PM
Finally, after a year's waiting and many hours of work, I got a chance to put my '88 20'Laveycraft in the water. This was a project boat. Completely re-wired, all new guages,added 10" Bob's jack to existing bracket(now how 20inch setback), somewhat experimental motor. I rebuilt a 2.5 litre 175 Carb Block and installed an '87 Laser fuel injection system. The usual stuff like solid mounts, Boyeseen reeds, 2.4 Bridgeport driveshaft housing and CLE case. For break-in I threw on a 23" High Five. I mounted the engine as high as possible on the jack and with the jack all the way down this prop barely holds. The engine ran well and feels pretty responsive...next run I'll put on something with more pitch. Have a feeling that a 26 Chopper is going to work out best. I mostly ran the engine at 3500 to 4000...with occasional bursts to 5000. Watching my duel pyrometer closely. She's well under 1100 degrees, but above 5000 I could see the Port bank climbing near 1200 so I backed off. I am opened to suggestions on how best to stay under 1200 above 5000 rpm. Thinking about installing a different fuel pressure regulator that I squeezed in a press until I got about 45 PSI. My current regulator (stock) is only showing about 32-35 PSI. I'm thinking the 45 PSI will richen things up and hopefully keep the temp under 1200 at WOT. I'm running 18 degrees timing. Heads are basically stock. Water pressure is around 12-15 at 4000 and both head temp guages show less than 130. When I get a chance I will run both compression and leakdown tests...she now has 3.5 hours on it and should basically be ready to roll. I will be switching to Amsoil Injector oil at 40:1 as soon as I run out the remaining fuel which is Premium gas with Merc's "plus" oil at 25:1. She does smoke at idle, but the idle quality was pretty good. I suppose when I install that 45 PSI fuel regulator that may screw up my idle and mid-range...may have to play with TPI huh?! This is an analog box so if I can't make it work I'd like to acquire something that is adjustable.
Anyway, it's a big relief to have survived the first water test and not have to lift the cowling or break out the paddle.
Also, the Nordskog GPS speedo works great...money well spent. How fast?.....when she's dialed in I'll let you know.
My goal is 80....I think it may be do-able with say a 28 Chopper....light fuel load, just a bit of chop to keep the bottom free. Time will tell. Can't tell you how great it feels to be back on the water with something to run other than customers boats.!

daytona
05-22-2001, 11:27 AM
Hi Sosmerc I think the ignition timing should be closer to 25 degrees. 18 degrees is so late that it may be affecting your pyro readings. rick

steve
05-22-2001, 11:40 AM
Have one for sale reasonably if you are looking for a good High 5 with a bit more pitch. stephano@coiinc.com

sosmerc
05-22-2001, 02:06 PM
Hi Daytona, yes timing would be at 25 degrees if I were using the detonation sensor and box, which I am not. So I will try raising the timing a little at a time and see how it affects my pyro readings. Just didn't want to start out possible running too warm at mid-range. I appreciate your advice.
What do you think about getting my fuel pressure a bit higher by using a regulator that I have modified to work at 40-45 psi? Any other tricks you can think of to fool my analog box into making things a bit richer if need be?

sosmerc
05-22-2001, 02:09 PM
Thanks for the offer Steve, but I already have access to 25 HighFive. I like these props very much, but I'm sure either a chopper or maybe even a LaserII will work better for achieving my speed goals.

daytona
05-22-2001, 02:49 PM
Hi sosmerc run your timing up some and try your squished reg. Timing at 25 degrees will make a big power difference and more fuel pressure will make it richer.10 lbs extra is quite a bit. I think timing and fuel mix will affect pyro probes, so try to get everything as close to merc specs as you can, then rely on exhaust temp to fine tune. You dont want late timing to be burning part of the charge in the exhaust tract and fooling the pyros.26 inch chopper with 20 inch setback sounds perfect on that lavey. Like my 21 eliminator tunnel it needs bow lift. Try a 26 chopper and you will never put the high five on again. Say, just how did you raise the fuel pressure in that regulator. rick

[Edited by daytona on 05-22-2001 at 04:52 PM]

sosmerc
05-22-2001, 06:06 PM
To adjust the regulator I first setup a test. Hooked up a high pressure pump off of a 2.4 bridgeport. Put a "T" fitting between the pump and regulator to attach my 100 psi test guage, finally just let the reg hang into a portable tank to retrieve the fuel coming out of the reg. Pressure was about 34PSI. Then I put the regulator in my press. I put a small 1/4 inch drive socket down over the little tube at the top of the regulator where the vacuum line goes. This way I was pressing on the area just below where the little tube goes into the reg. I just pushed it in a little and then set up my test again. Kept doing this until I got about 45 PSI. I know that there are some race motors that use 56 PSI...but those regs will not fit into the vapor tank like the Laser style EFI uses. I have no idea how much richer this is going to make my system. I do not intend to try it until after I have first set timing up some. Then I may disconnect my Port head temp sender (that will richen things up also 30% or so) If I need more I can also disconnect air temp sensor...good for another 10 %). Someday I'd like to see a pyro probe at the exhaust port for each cylinder. I am aware that high pyro readings good be unburned gas getting lit up and burned below the powerhead. For further experimentation I have at my disposal a test box made up of six temp guages that utilize
probes under each spark plug. In order to make room for the probes I had to have my machinist grind out a recess in each plug hole. But, my thinking is that by looking for a major difference in temp under each plug I might be able to narrow down a rich or lean condition to a particular cylinder. I have not hooking this setup to a v-6 yet, but I have played with it on some 2 and three cylinders. I think it could be helpful in some situations. If a plug were very cold relative to other plugs you might suspect an ignition problem, or a cylinder that wasn't getting any fuel. Something more to play with. I've got lots of ideas and things I want to try....just need to buy some time. It is now the peak of boating season here in the Pacific Northwest and I am about 3 weeks behind. Weather is perfect and so everyone is screaming for their boats. Where were they in February and March.?!

Rickracer
05-27-2001, 10:06 AM
making that regulator adjustable? Some of them (generically speaking)lend themselves to threading the nipple for an allen setscrew, with a vaccuum passage drilled through it. This would make it precisely adjustable. Just a thought...

sosmerc
05-27-2001, 01:33 PM
Yes Rickracer, an infinitely adjustable regulator would be a good thing. My problem is Laser EFI uses a proprietory regulator that "fits" into the top of the engine's vapor tank. I don't see anyway to modify the existing regulator...however, I guess one could drill and tap the hole where the regulator mounts and then use a barb fitting so the the regulator could be of a different design and simply go anywhere between the rail outlet and the vapor tank inlet. I suppose the Holley regulator could even be used, although you would give up the "vacuum" adjustment that the stock regulator uses. I have a lot of things to try first. I am going to start by slowly bringing my timing up 2 degrees at a time and looking for pyro reading changes.
If I don't see my temp coming down some above 5000 then I will install my "squeezed" regulator and see if more fuel per squirt is needed. I'm also eager to see if switching to synthetic is going to have any detectable different to exhaust temp (don't plan to do that until I've got about 8 hours on this powerhead). Was hoping to do some testing this weekend, but the wind has come up so I may be doing some tinkering on the trailer. I don't know, I'm also watching the 500 and also looking forward to the 600 at Charlotte tonight.....feeling the need for speed!!