Yeah, I was very fortunate to stumble upon this. Just happened to be looking for TRS drives in Seattle Craigslist. Ad was 7 hrs old. Fate I suppose.

I've been less than impressed with these massive outboard boats these days. Seems like the go-fast vee hull with inboard engines is on it's way out. All the more reason to maintain the boat that has links to the offshore racing legend...even if it's just a little bit.




The tops of the upholstery took a beating from the UVs. Next years problem to solve. In the meantime, I'll likely cut out new marine vinyl to the piping on the top and glue it on. Then try out some vinyl renew spray to see if that works.

Got the port floor board out. It was quite the fight... both floorboards are waterlogged. If I have time, I'll cut the bottom glass out and remove all the plywood. Then add another piece of ply and laminate the 2 fiberglass pieces together...at least that is the plan...until glassdave chimes in...lol.



Engine bay is it came. 30 year time capsule. Orange extension cord is from the low temp heater system you can see behind the port engine. You can see how forward the engines are. I wouldn't be able to service the raw water pumps or even really hard to change a belt. Amazing how preserved most things are, despite the time in the PNW.

The engine cover was raised a few inches to create room for the flame arrestors.



The engine hatch needs some work. The plywood bottom has the plexi mirrors on it. But no fiberglass base to the cover...that I can see so far. Top of cover has a slight concave to it. I don't want to put the mirrors back on. The plan so far is to flatten the cover...glass the bottom...and get my 2 girls to name the engines and draw a mural for each one. Something like that.

These photos were from when I was military housing, summer 2023, just before I retired.

I'd always been a SBC fan...never really looked into BBCs. It's taken some time to bone up. My forever plan was to pull BBCs out of whatever boat it got, and put SBCs in place. Now that I've grown up...lol...I see that the BBC is really not that much of a weight penalty. I weighed a bare BBC Gen 6 with Main bearing caps...and it weighs 220lbs. Not much extra over the SBC. That was always my intent...to lower the engine weight. Now I see that I can only do that so much before the hull doesn't perform as intended.

I would call Cobalt factory just for the hell of it and tell them what you have.
They may have some interesting info. I have called several times on my 05 343 and usually have been very helpful.
Yours is a lot older but you never know. Pac- the founder is a really good guy and has a place on Grand Lake. Cobalt was bought out a few years ago and he retired but several of the same people are still around. Worth the call.

Yeah with my 30ft Cary very similar old heavy V str bottom I always thought some stout svc would be way to go. More room to work etc.. Easier on drives too. Problem is you would have to turn some serious rpms and have serious motors with expensive parts. BBC always seemed cheaper and had lower rpm torque which a heavy boat likes, however there were some killer race boats this size with Sbc that were sick fast

Modern heads and parts really make a SBC different animal than even the 80s.

Honestly, I was really shocked at the weight minimal weight difference off BBC blocks and parts. I was thinking of doing a thread on the GM Marine BBC forged longblock...essentially a 365 Mag. Photos, part numbers etc. There's been a a lot of 365 Mag questions and I couldn't even find photos of the pistons.

As for going SBC...once you go down a path, it's really hard to deviate. Just the cost of getting new performance exhaust would be prohibitive.

Great find! If you ever, EVER sell it please contact me or post it on the “your classic cobalt” facebook page.

Hey I had not seen your resto project, now I may have to start my scarab resto thread, biggest problem for me will be posting pics, if you ever decide to get rid of the 420 blowers let me know, I have that tall deck 496 with the correct 420/250 tall deck blower intake manifold, I am a good year from getting my scow into water, how long for yours, maybe meet up in San Juan’s

I think your bbc blowers and arneson drive will be way faster than my sbc 388 with blowers, hopefully ditching the trs drives and transmissions and going with aluminum heads/watermanifolds/water pumps and Volvo dp drives saved me a lot of weight. I know the dp drives not the best for speed but will see I guess.

I ended up refocusing on the Formula 233. More practical for me and the family around here...and far less complex to get running. I'm thinking of going NA on the Cobalt engines. 600hp 454s are relatively easy these days. Saves weighr and complexity. Moving the engines aft is probably something that needs to happen. Fabricating extension boxes would be the way to go. Engines back around 12". Something like that.

90mph would be a good reasonable speed goal. RPM around 5800-6000 with a 14-16% slip.

I had the issue of the fuel tanks covering up the bilge drain holes from the cuddy. Thinking about just running a bilge pump in the cuddy. Easy solution. Then seal the holes. Bilge pump would likely move more water than the 2 small bilge holes with gravity feed anyway.

Wow that engine bay is stuffed, need to be an 11 year Chinese Olympic gymnast to do anything in there, that was one of the things I did with the scarab, moved the engines up and over 3/4 for watermanifolds clearance and spark plug access.

The Damn Carrera raceboat was staggered twin small blocks and with no back seat a lot more room and better balanced.
The 27/30 Carrera's are tight in the engine compartment and all that weight in the back is not conducive to good running angle.
My belief is you would have to blueprint the bottom and throw a LOT of power at it to run 90s, Id say a real dyno proven 800hp per side.
I have a 32' Carrera raceboat different hull than the (27/30) that also had Arnesons orginally but also had small blocks.
It was swapped to Bravos on boxes later in its racing life.
I also had a twin to your 30 a while back, it had twin 440hp/454 with Trs , I ended up parting out the drivetrain and selling the hull by itself.