Engine options
 

Was a big block chevy engine optional in a 1986 scarab1 - 21'?

Spec sheet says "Max. Horsepower: 260", then on the options list, it didn't mention engine upgrade, so I'm not sure if someone special ordered it, or swapped in more power. Dan at Archer Marine could probably answer that question off the top of his head!

I don't have an '86 brochure, but if its the same hull as the attached image from 87 or 88, just without the integrated platform.

As far as I know Wellcraft never offered the 21 with a big block.

'85

https://cimg3.ibsrv.net/gimg/www.off...6a337fce6b.jpg

Short answer is no

[QUOTE=phughes69;4787711]Short answer is no/QUOTE]
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Thanks, here is my delema, i recently bought a 1986 scarab 1 with alpha 1 outdrive (inside of boat) with other misc parts, and big block chevy exhaust manifolds with risers and was told the last engine in it was a bbc, however the thru hull exhaust holes in transom are in stock location, i just picked up a 454 short block but wondering if i would be better off installing sbc and selling the bbc parts

Really depends on your budget and goals. If you keep the alpha drive, go with a small block.
get up to ten posts and post some pictures

Scarab 1
 

Ive seen a few of the members scarab1 boats & mods turn out really good, & wondering if anyone has one of these older 21' scarabs with the bbc installed & if it drastically changes the handling characteristics of the boat, also the boat does not have trim tabs, are they a must with a big block?

I had the newer model, a 1989 w/SBC and I think they optioned BBC/330hp starting 1990. Not sure if hull bottoms were the same, but mine had a pad.

Scarab 1 engine options
 

Has anyone put a high revving 302 chevy small block in a 21' boat

Drive becomes a problem I think. Max designed rev is around 5-5200 for Alpha. I've turned them 55-5600 without issue (blower was the issue...different story)

Not sure how relevant this is...but just throwing it out there...I have a 21' Baja with a big block in it, it does just fine without tabs. It's got a 17 degree deadrise...not sure how that compares to your Scarab? Weight is around 3,500 pounds.

The big block wasn’t offered before merc had a good option for a drive without a transmission. Bravo drive wasn’t available until ‘88.

plenty of later small block options that don’t include the old school thought of a dz302

what kind of speed does it run, & u pull skiers also?

Engine options scarab 1
 

Ok i hope im not entering this twice, but when i submitted it, it disappeared, may have deleted, i am new here and hope this isnt a dumb question but just like tricking out a motor & making it twice as good, can the alpha 1 outdrive be "tuned up" or made better like maybe spin balance shafts, gears, upgrade to harder metals at weak points. And curious what is a ballpark figure to upgrade to the bravo 1?

I don't know of any modifications to improve the strength of the Alpha, it's just plain small. I have sold used Bravos with transom assy in good condition for $3,500.00. Good used parts are out there, you just need to be patient.

Valid question, but would be a waste unless they had one and just had to do it. Cubic inches are your friend. 350/383/406 much better small block choices. I have not been in a ScarabI with big block, so can’t answer how they handle.

Mid-to-high 60s with a 21" labbed Mirage. Great for watersports, I used to ski and kneeboard a LOT before I got old, lol!

Engine options scarab 1
 

I am going with the bbc 454 that i have, and is the starter in different location for marine use, can a truck block be retrofitted ?

I’d stay with the BB and add a Bravo drive and you’ll be happy for a long time. Replace as much cast iron off the BB with aluminum bits and you should be close to the oem small block.

Caveat: I really know Jack **** of what I’m talking about but that would be my path to explore.

Engine options scarab 1
 

will the starter location be same on a truck 454 block as it was on the 350 sb that came in boat?

Engine options scarab 1
 

Im trying to use the flywheel cover that came with boat, also trying to id if block it mark IV or gen V, it has a fuel pump mount but block off plate bolted to it and also has hole for crank sensor on bottom of timing cover ? Any help appreciated

starters are in the same location on a SB and BB, unless a top mount rear CCW starter is used in a trans application

Engine options scarab 1
 

https://cimg4.ibsrv.net/gimg/www.off...8dfd49d7d2.jpg
1st time tryin to post pic. Here she is old but solid transom

^ looks good!

If you spend some time going through the Mercruiser parts diagrams, you should have a good idea of what you have and what is required to make the swap....

https://www.mercruiserparts.com/part...ndrive-inboard

Engine options scarab 1
 

Thank you

Merc had 330hp BBC in front of Alphas for a couple of years. Late 80s maybe? waiting on the Bravo. A friend had one he bought new that lasted until he decided he wanted to hop it up quite a bit, then it didn't make the next summer. :(