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STV_Keith

My new motor???

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My 2.4 BP EFI motor is just about back together now.  The block and heads are due back from Jim Ruck next week.  The block now has all steel sleeves.  Ruck worked the finger ports, transfer ports, opened up the rod slots and ported the exhaust chest.  Heads will be at 33cc to run pump gas.

I've also procured a LW aluminum flywheel for it now, and will be setting this on an offshore mid with my sportmaster gearcase.  It's also got the "big rods" going in it for reliability.  Jim is saying he's expecting the motor to make roughly 280hp at the propshaft  (YEE HAA!!! ).

Previously, the motor was mysteriously limited to 7000rpm.  We think we've found the reasons for that - a 1/4" fuel feed line and an oiler crank with no gear.  I believe this is what caused the #2 piston to fail.  We have since fixed those two items.

It had run a best of 97.5mph with my Mazco RE3-29 at 3/4" above the pad, 2-up.  That was turning 7000rpm on the tach.  If the limiter issue is now rectified, with 7800rpm on tap, I should be able to see 108 with the same prop from my calculations.

What props are you guys running for the big speeds?  I was thinking about something in the 14.5x32 cleaver area.  With a boat weighing in at around 1500# wet with me in it, do you think 120mph is unfeasible?  A friend of mine has the boat builders program, and with that weight and power, it seems to think 120mph is the terminal velocity.

Thanks.

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My Euro and a Merc lab 14.5x32 pulls 7500 at 111mph. You should do about 5-7 more if you indeed got around 280hp!

Good luck and keep it safe.

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120 mph with a 2.4- you will have to spend hours on setup and testing. with what I have seen, 113 ish is about the best they will do with a 2.4- anything above the 113 mark you are bettering some serious hot boaters- good luck

paul b.

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What PaulB said!.

You will need 2.5 power to see 120.......and stock 2.5 power will not do it.

I suspect with 280 hp you should see 110mph, with a 14.5 X 30 or 32 cleaver depending on how high you want to rev the motor. Get a MERC and only a MERC cleaver for top end running.

NO setback if you want top end on that boat.

And as Paul said, the best running 2.4 powered ProComp we have ever seen ran 113..........ONCE, for referance it ran a 14.5 x 30 cleaver at 8100-8300 rpm if my memory serves.

Their a few tricks for more speed, once you have a baseline, let us know.

RT

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Thanks Firewalker.  Maybe I'll move the bar a little (I sure hope so).  :)  Currently my biggest prop is a RE-3 29, so from what I figure, about 108 will be the top end with my self-imposed 8k rev limiter.  Once I get it broke in and running up there, I'll look into other props.

I've currently got 6" of setback on a CMC manual jack plate, set at 3/4" above the pad.

I'll let you know once I get it in the water and broke in.

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Well, we got the crank layed in the block last night, and the port side piston/rod assemblies in.  Things are going well, however we thought we were sunk at one point.

When we pulled the original wasted crank out, we thought it was a big upper bearing crank, so that's what I got to replace it.  Well, turns out it was a small upper bearing crank, so my old upper bearing wouldn't fit.  Luckily, my buddies 2.4 had the big bearing and was apart, so I robbed his parts.

Should be able to get the other 3 rod/piston assemblies in tonight, get the heads on and get the front half and other stuff on.  Plan to install it on the boat Friday, and fire it up.  Should be on the water Saturday for break in.

YEEEE HAAAA!

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Well, bad news tonight.  Found out on the last piston to go in (#5) is an oversize.  It measured .020" larger than the rest, so overbored for a wiseco piston, which is what came out of it; but aparently a +.015" wiseco piston.

So, all the stuff is back out and the block will go out tomorrow, back to Ruck to have this sleeve cut and resleeved in the stock size.

Probably won't be until after the new year that we get this thing together.  :(

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More hurdles, but it's together!

Got the block back Friday and started putting it all together.  Hurdle #1 wasn't until my old stator wouldn't fit the new (big) upper bearing support.  Luckily, my bud Kevin had a new one in the box from when he was troubleshooting his 2.4 a while back.  Up and over!

Hurdle #2 was when torqing the #5 spark plug into the hole, it FELT like I stripped it out.  Turns out the threads on the plug broke!  New plugs fixed that.

Hurdle #3 was my new aluminum flywheel.  We tried to turn the motor over to find the starter bendix just barely engaging the flywheel.  # of teeth is correct, but when comparing to Kevin's LW flywheel, the diameter of mine is about 1/4" smaller on the ring gear.  Some wierd thing I guess.  Can I buy just a ring gear?

Anyway, finally got it together and on the boat.  After 6 - 15 minute sessions of 1500-2000rpm and idle running on the hose, we took it to the lake today.  2 hrs >3k and 1 hr at >5k and it's running great.

Look for my full report with pics of everything in the near future.

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Sounds Cool Keith...Post some pics of the motor for us too!!!

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Excellent pics and movie clips Keith. Very neat to see the guts of an engine in parts then together and running.

The running movie clips were awesome. I never drove my boat as the lake was froze, but man I think I got the itch big time after those clips.....16 weeks till thaw really isn't that long to wait..or is it! Have fun Keith.

Dreamer

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KEITH THANKS for sharing those familiar sites and sounds with me.

I really like what you have done to our old rig. It looks clean and mean!

Finally cool to see a pic of the guy that bought our rig too. It was almost like you bought it mail order from me...pretty cool story...when you think about it!!!

THANKS AGAIN

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KEITH,

I could not get the new movies to run..anyone else have a problem???

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Try this...right click on the filename and choose "save target as" which will download them to your computer.  Once it's on your computer, double click the filename in explorer.

I assume you guys are running Windows Media Player?

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