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Hi there, I have a 454 with a cracked head in our 1978 Caribben Daycruiser 26' with a TRS outdrive. I also have a ls2 from a GTO with 1500 miles, What parts will be needed to convert to marine? I did a ls1 conversion in my 1969 camaro about 4 years ago, but not sure on the water pump lines o2 sensors.....ect and help would be gr8
 

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I'm just finishing up an LSX swap myself. There are a few things you'll run into. The LSx engines have a different bolt pattern on the crankshaft so it will take a different PTO. I couldn't get anybody to understand this so I ended up having an SBC PTO redrilled. Also GM used 11mm flywheel bolts. This is an odd size and it proved impossible to find any that would fit in the countersinks on the PTO. I ended up tapping my crank to accept a 7/16-20 bolt. You'll only lose abot every third thread so as long as you have enough threads engaged you'll be fine. You'll probably have to use a shallower oil pan (F-body or a C6). As far as exhaust, I run OTT headers and fortunately Schoenfeld is a local company. They were able to modify a set of sprint car headers to work. There is also company in Australia that makes marine exhaust manifolds for the LSX. The cooling system was easy, pm me an email address and I'll send you some pics of what I did. You can also get away without O2s and MAF. If you have any other questions I'll try to help in anyway I can.

**Edit**
This was on a jet so if you're running something else then I don't know how much of this will apply.
 

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I'm just finishing up an LSX swap myself. There are a few things you'll run into. The LSx engines have a different bolt pattern on the crankshaft so it will take a different PTO. I couldn't get anybody to understand this so I ended up having an SBC PTO redrilled. Also GM used 11mm flywheel bolts. This is an odd size and it proved impossible to find any that would fit in the countersinks on the PTO. I ended up tapping my crank to accept a 7/16-20 bolt. You'll only lose abot every third thread so as long as you have enough threads engaged you'll be fine. You'll probably have to use a shallower oil pan (F-body or a C6). As far as exhaust, I run OTT headers and fortunately Schoenfeld is a local company. They were able to modify a set of sprint car headers to work. There is also company in Australia that makes marine exhaust manifolds for the LSX. The cooling system was easy, pm me an email address and I'll send you some pics of what I did. You can also get away without O2s and MAF. If you have any other questions I'll try to help in anyway I can.

**Edit**
This was on a jet so if you're running something else then I don't know how much of this will apply.

any pics.....:D
 

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A company called S&W race cars makes the front plates. All I had to do was notch the corners. I think they were like 100 bucks for the pair. For the back I just cut a semi-circle out of a piece of aluminum bar and drilled it to fit the bellhousing. I drew out the water-pump block-off plates on 1/2" aluminum stock and had a buddy cut them out with a band-saw where he works. He then drilled and tapped them for 1/2" npt fittings.
 

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this is great! this is exactly what i want to do with my dads little 17' sanger flat. I was also thinking about picking up a jag supercharged V8 (im a jag tech) super light and over 400 hp...should make our little v drive move pretty good. plus i love the look...definitely make people stop and ponder. great work on that thing. is it on the water yet? do you have any gps numbers with it?

AP
 

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another thing, you are running drive by wire right?...it looks like it from the pics. how did you do the throttle? did you modify the pedal or did you run a normal throttle cable to another drive by wire pedal?

AP
 

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Yeah I got it on the water for the first time weekend before last. We didn't get alot accomplished that trip but we have had it out on the river every night this week trying to get the tune dialed in. Max speed on the GPS is 60.4 mph at about 4300 rpm on a AA impeller. The motor is a stock LQ4. I did put an LS1 intake on and obviously it has headers. It is DBW and I just mounted the GM truck accelerator pedal in the boat. I was thinking about mounting the GM pedal under the back seat and using a cable pedal to actuate it but I really like the way this worked out. Thanks for the compliments.
 

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4300 on an AA is faster than I would have thought. Thats stock big block territory there. I had always wondered how a LQ4 or 5.3L would do. I would like to swap one into my jet, but just have not had the time yet.
 
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