Newbie 21' scarab build
 

New here on the forum. I had a nice turn key 86 chapparrel with a 454mpi but sold it like a idiot right before boating season to buy this 89 21' scarab excel. I was told all it needed was a motor, (sb350) but now after pulling things apart I found it needed a lot more. I wanted to do something different than a 350 so I bought a 5.3 outta a 2002 suburban. there gen 3 ls based engines that put out good power i thought it would be cool in a boat.

here some pictures, the boat looks horrible i think. the guy i bought it from was obsessed with stickers and spray paint

[IMG]http://i47.photobucket.com/albums/f1...d/DSCN0118.jpg[/IMG]

i cant tell if the swim platform is factory, if it is shame on wellcraft..... its coming off

http://i47.photobucket.com/albums/f1...d/DSCN0117.jpg

inside looks pretty good

http://i47.photobucket.com/albums/f1...d/DSCN0110.jpg

here u see where the sticker freak left his work

http://i47.photobucket.com/albums/f1...d/DSCN0147.jpg

old engine

http://i47.photobucket.com/albums/f1...d/DSCN0113.jpg

new engine

http://i47.photobucket.com/albums/f1...1495744893.jpg

got bottom end together and painted

http://i47.photobucket.com/albums/f1...d/DSCN0146.jpg

valve job and comp cams spring kit

http://i47.photobucket.com/albums/f1...d/DSCN0144.jpg

Good progress bud, keep us updated

That's gonna fly when you get it done. There is a lot of power potential in the ls motors. Looks like a fun project. Im in the same boat just finishing up a project that "only needed a motor". Somehow I don't believe the words "upkeep" or "maintenance" were in the previous owners vocabulary.

Welcome aboard!

Sweet project. Subscribed.

Good engine choice. What manifolds do you plan on using?

Thanks every one!

there a site that sells them im not on my computer right now so I don't have the link, il post it later but there made by PCM. around 900 dollars.

made some progress got boat apart and found the gimble housing was trashed so had to pull that off the studs through the transom were dust they were corroded so bad. the housing corroded and expanded squeezing the ply wood together. the wood is still solid so I think im ok but im gonna have to do some filling to make smooth and even so the big oring will seal. lotta work I wasn't expecting. I did get lucky though and found a parts boat for 50 bucks! has a nice lower unit on it. il get some pics up tomorrow.

Welcome, That will be a nice little hot rod when you get it all together. I will look forward to your progress. Randy

got motor out and found the steering arm had so much play idk how the guy could even drive it. I could literally move it 2 inches back and forth.

http://i47.photobucket.com/albums/f1...d/DSCN0114.jpg

here all the other problems. the corrosion squeezed the transom together

http://i47.photobucket.com/albums/f1...d/DSCN0151.jpg


http://i47.photobucket.com/albums/f1...d/DSCN0150.jpg

not really sure what to do about this, my body shop friend says fill it with some fiberglass bondo called dyna glass? does that sound ok?

http://i47.photobucket.com/albums/f1...d/DSCN0148.jpg

boat looks much better with out the home maid swim platform.

http://i47.photobucket.com/albums/f1...d/DSCN0149.jpg

here the parts boat I got for 50 bucks! I would like to put a bravo on it but I just don't have the money. plus this things gotta be done by july 20th!!

http://i47.photobucket.com/albums/f1...192417_121.jpg

any updates? I've got an 89 21 excel as well so I'm very interested to see how this works out for you.

I LOVE THE NAME ON THE STERN -VERY IRONIC:lolhit:
COOL BOAT -I HAD A 21 O/B THAT DID 83 GPS -YE-HA WHAT A RIDE!!
GOOD LUCK ON HITTIN THE WATER

sorry for slow update. been busy. got it painted just went with white. I plan on putting some graphics on it later

got it smooth

http://i47.photobucket.com/albums/f1...193056_741.jpg

http://i47.photobucket.com/albums/f1...193132_813.jpg

http://i47.photobucket.com/albums/f1...204407_652.jpg

http://i47.photobucket.com/albums/f1...114240_934.jpg

http://i47.photobucket.com/albums/f1...113844_808.jpg

Looks great
i like all white w/min. Graphics

thanks!

got the cam and oil pump on. about to put the heads on. I went with comp cam 273hr-12 220-224 duration at .05 112 LSA. 1600-6600 RPM range hopefully its not to aggressive I guess we will see.

http://i47.photobucket.com/albums/f1...133001_503.jpg

I wanted to do fuel injection but for now went the easier route with carburetor. here is the edlebrok ls1 carbed intake.

http://i47.photobucket.com/albums/f1...131159_626.jpg

cleaned the bilge up and did some filling. got a gallon of rustoleum white gonna make her shine


http://i47.photobucket.com/albums/f1...131252_149.jpg

http://i47.photobucket.com/albums/f1...131307_087.jpg

hell yeah man that look nice. I'll be watching this build really close as you are doing exactly what I'd love to do for mine.

Cool little projects. I dig the choice of the 5.3, they are pretty tough motors. You might see somthing arond the 330-350 hp range with the cam you picked, exhause and properly tuned carb and intake.

So did you meet your goal of getting it in the water by the 20th? I'd love to see more of your build.

Your build got my attention because I just recently built one of these boats just to resale . It has a 454 with cam , intake , and carb . I tried a blackhawk on it but then switched to a bravo for the sale . Fun little boat , really easy to drive and turns on a dime . You will enjoy it when your done . Good luck with your build .[ATTACH=CONFIG]505051[/ATTACH][ATTACH=CONFIG]505052[/ATTACH][ATTACH=CONFIG]505053[/ATTACH][ATTACH=CONFIG]505054[/ATTACH]

no i didnt, sucks. some stuff came up im working in it this weekend il try and put some pics up.

nice boat! what did it do on gps

Man don't lose focus! You have a cool little boat that will haul a$$ when you get done. She is close too, so keep rocking. Shoot for a water test by mid/late Aug and you'll be running solid in time to get the some of October to enjoy her. Hell, down in VA you can probably run till mid November. The put her up for the winter and do interior/stereo and finishing stuff. Next spring rolls around and you'll be rocking!

Watching this one also. Curious on more info with the 5.3 LS setup. What does it take to swap to the 5.3 from a 350 setup? Flywheels, flywheel housing, motor mounts, exhaust, etc. I have twin 350's now and am in the process of building new plants for the future like john has (Sprink on the formula section). One short block is done minus cam, getting ready to take other block in to be machined. Always thought about upgrading to LS series, but I do not know what it would take to change over.

Sweet. your post tempted me register here and this is my first post. Ive got a 89 checkmate 23' that i put a 5.3 in this summer. its running good but i need to get the ecm tuned. its only running about 58mph on gps. i detonates real bad at 4800rpm and stops pulling. you will love the boat with that motor. go efi if its not too late. i hook you up with tips if you want. i went with closed cooling also to save the aluminum heads. going out on it now, ill try to post some pics later.

thanks for the motivation, I needed that right now.

im sure benhaizlett could answer your question better but from what im finding its not to bad of a swap. bellhousing is the pretty much the only thing that's the same though. manifolds are different and are around 850$ from what I could find. 4 bolts for motor mounds instead of the 3. as far as ignition and fuel goes fuel injected would be a better but more work and tuning. I went with carburetor witch gives you a little bit more top end power. my friend put the carb set up in a 78 gmc and it runs great. I would of rather gone with the 6.0 but considering the 5.3 was free I guess I cant complain.

im jealous! im sitting here looking at a empty bildge. LMAO. yea post some pics!

I should hire you to paint my boat, Looks really good. Keep up the good work. Randy

what are you deciding to do for cooling? where did you find the manifolds at?

not sure yet im still trying to decide whether to go with the alpha water pump or put a sea pump on it.. any suggestions??

here the manifolds. http://www.skidim.com/products.asp?dept=1157


got a little done hope to have gimble housing on this weekend. here where im working

http://i47.photobucket.com/albums/f1...d/DSCN0294.jpg

got bilge done and painted. used rustoleum white.

http://i47.photobucket.com/albums/f1...d/DSCN0295.jpg

http://i47.photobucket.com/albums/f1...d/DSCN0296.jpg

gimble housing from old boat gonna clean up and rebuild

http://i47.photobucket.com/albums/f1...d/DSCN0297.jpg

http://i47.photobucket.com/albums/f1...d/DSCN0298.jpg

waiting to find a harmonic balancer for motor need it to align the from cover with the seal.

http://i47.photobucket.com/albums/f1...d/DSCN0299.jpg

im planning on running raw water cooling using the alpha pump for now. the harden marine sea water pump looks great but at 800 bucks i dont see it necessary right now. man those manifolds are cheap. are you eliminating the neutral interrupt switch?

Yea I saw that on Harden site that thing is sweet. Idk what I'm gonna do about the interrupt switch guess il call msd. I'm thinking beaking ground to the coil packs but I haven't looked at it yet.

how are you hooking up the gauges? you going to keep the factory ones or you replacing them?

I love this thread!!! When you do decide to go Bravo...save a bunch of $$$ and use a crank driven pump. I used two on my Formula twin MR/Bravo conversion...very simple...works great.

The intake ports on those LS heads could swallow a pack of cigarettes!!

I emailed msd about seeing if they have a way to allow for the shift interrupter switch to work with their system for these engines. I'll let you know what i find out from them. I have a post going about what all is needed to do a full LS swap and you are more than welcome to add any suggestions or comments from your experiance. I'm sure you are going to fab up your own adaptor plates to go from the four bolt to three bolt set up. I've found tons of them on ebay for 25 to 80 bucks depending on how pretty you want them..lol

[IMG]boat.jpg[/IMG]

tried to post pics of my boat but its saying not authorized.

A little about mine..
I used the hi tek stainless headers, and made the pipes out the back. bit the bullet and got the hardin marine pump. mines a bravo so I didn't have another choice that i found. i think i got the first hardin pump for the ls sold! not sure if it will work correctly with the ls1, but on my 5.3 it was way too short and when bolted on it hit the water pump. I made a bracket to bring it out to line up to the serp belt and it works fine. sucks to pay $900 and then have to modify. you cant use a crank mount pump on these engines with the stock harmonic balancer because its like a thin 3 spoke design. unless you modify the ? i used a stand alone setup from shwanke engines for the electronics and fuel system. great product. and they have everything for 850. ecm, harness, fuel pump, fuel lines, fittings, fuse block, relay. the bravo coupler bolts up to a stock manual trans flywheel without the locating dowels. i used adjustable conversion motor mounts. closed cooling from seakamp. lots of fun matching up the boat harness to the new one.

its hitting a power loss and detonation at 58mph no matter which prop i use. tried 19p and 23p and some random 4 blade i don't know the pitch of. i need to check fuel pressure because its detonating real bad at that speed. i think the fuel pump is not keeping up. not real worried about it as it runs great otherwise, and im probably procharging it this winter so fuel and tuning setup will change anyway.
great power to get on plane and midrange is awesome. it cruises nice at about 42mph at 3200 rpm. got probably 300 miles on it so far. bunch of trips from quantico to Fairview and once into dc. sounds like a open headers vette! so much different than old school sound.

any suggestions on how to post pics and ill get them up.

250kelly, i will see you on the water if you run the Potomac!

use photobucket? thats all I'm using I have a couple threads, one as you know is the LS swap details, the other is a rebuild on my boat.

I love the work done so far on here. If my budget wasnt stretched currently I'd have to follow suit and paint mine... I'm drooling of what you have done so far. I'm still trying to find the perfect LQ4 for mine, but patients sometimes pays off. I love seeing some of the smaller boats getting attention. Granted who doesn't love seeing a monster twin drive boat all done up... I just think these 21' scarabs are pretty bad a$$ little hot rods.

MSD responded, the interrupter switch can not be interfaced with their unit. However, as far as I can tell. If you wired up the interrupter switch to the main power line, it would cut the power and cause the engine to studder. as far as I can tell it should work just like the OEM when it grounds out the dizzy. it happens so fast that you have restored power before the crank can come to a full stop. So, assuming I'm right it would resume operating. only one way to find out however...

great thanks for the info. yea idk what to do about that . im wondering if the repeated on and off lot power to the msd box is bad. il look at it when I get home cause im thinking I could just run the switch through the ground wire for the crank sensor. im in the hospital now for the night I was cutting tree down in the yard and limb fell on my head had a concussion and neck is sore so prolly wont get to do any thing til monday

Ouch damn man glad you're okay. Yeah the sensor might work better. Simply have it cut the signal instead of grounding it. All you need to do it cause an engine studder for a fraction of a second.

yea good idea. hey did any body see the new episode of legend Shelby the swamp man? the one came on this week he hits something and the dogbox flies off and you see a vortec block sitting there! I guess marine power got ahold of it and put their 6.0 in it. bad ass!

hey ben did you use the factory 5.3 water pump? and can you run yr lab top and get live engine data? I head these motors don't like a lot of advance compared to a 350 especially in a boat

did you sell boat yet?

No they don't like a lot of advance I've heard its down around 27 degrees total. I'm planning on the stock pump on my engine. I figured what the hell why not...