SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: 88CARRERA on August 20, 2009, 01:34:28 PM

Title: bbc question???
Post by: 88CARRERA on August 20, 2009, 01:34:28 PM
found a good deal on a roller bbc 454 with a 427 crank? any info good or bad???? thanks
Title: Re: bbc question???
Post by: obnoxious001 on August 20, 2009, 02:12:52 PM
The only info you have given us to go by is that it is actually a 427, not a 454 if it has a 427 crank,, bores are the same.

You need to supply more details if you want any kind of valid opinion on value, power, worth buying, etc?
Title: Re: bbc question???
Post by: 88CARRERA on August 20, 2009, 02:39:55 PM
the guy told me it was a 454 with a 427 crank. it has roller valve train, high rise and dominator carb. this is the only info i have. it has a big cam, the car it came out of had a 2700 stall converter. i guess my question is why would they put a 427 crank.
Title: Re: bbc question???
Post by: Luckie Stiff on August 20, 2009, 02:45:23 PM
i guess my question is why would they put a 427 crank.

if my memory serves me right, Tom @ JBP has done a similar engine, at the time he explained it to me, it made sense but it's been a while since then, maybe he or Josh can chime in with some info
Title: Re: bbc question???
Post by: enginedoctor on August 20, 2009, 04:38:09 PM
I BUILD THEM ALL THE TIME.

THE ONLY DIFF. IS THE STROKE ON THE CRANK,SAME RODS,SAME BORE SIZE...RESULTS BETTER TORK  ;D

MOST FREQUENTLY DESIRED FOR C 2 CORVETTES ETC.   :)
Title: Re: bbc question???
Post by: 88CARRERA on August 20, 2009, 04:49:42 PM
thank you! so i am safe in assuming this would work fine in my project?
Title: Re: bbc question???
Post by: enginedoctor on August 20, 2009, 05:10:41 PM
thank you! so i am safe in assuming this would work fine in my project?

NO!!   U need to give us more info on the build Sir.   :)
Title: Re: bbc question???
Post by: 76 Bonneville on August 20, 2009, 06:37:21 PM
I'm running a 427 in my Rogers. I would prefer more cubes.
My boat came with this motor, so it was cheeper to freshen it up rather than buying a new rotating assembly. 454 block, 427 crank, closed chambered heads, 630 lift solid lifter cam, 12-1 comp, 110 fuel, C  cut impeller, 850 Holley and so far a top speed of 80.4.
Title: Re: bbc question???
Post by: SLCKREG on August 20, 2009, 06:55:34 PM
80 isn't to shabby...I haven't quite got there :mad: :banghead:
Title: Re: bbc question???
Post by: enginedoctor on August 20, 2009, 07:05:53 PM
I'm running a 427 in my Rogers. I would prefer more cubes.
My boat came with this motor, so it was cheeper to freshen it up rather than buying a new rotating assembly. 454 block, 427 crank, closed chambered heads, 630 lift solid lifter cam, 12-1 comp, 110 fuel, C  cut impeller, 850 Holley and so far a top speed of 80.4.


Question of tork or top end IMHO :P
Title: Re: bbc question???
Post by: IRRebel on August 20, 2009, 07:42:47 PM
The 427 and 454 are identical in all but stroke. More cubes does not necessarily mean more HP. The shorter stroke of the 427 is VERY desireable in lighter vehicles because of the quick ramp-up in rpm. 'twas why it was developed for the Corvette.  As cars got heavier, they stroked it to 454 to gain more low end torque, but not necessarily more HP.

You'll be perfectly fine with 427 cubes. The rest of the engine? Well, that's a mystery to us as to whether it will suport it. Personally, If the 427/450HP Corvette was the pinnacle of performance, you'd have a hard time convincing me that an 18' jet boat out weighs a 67-69 Corvette. The math from there is inarguable.

Then there comes the 2 bolt- 4 bolt debate, but I'm outta that one.

Ray
Title: Re: bbc question???
Post by: enginedoctor on August 20, 2009, 08:33:14 PM
Is the question ... 2bolt or 4 bolt   ??? ???

IMHO.....Under 6k rpm 2 bolt should be ok.....(Based on application)

The 2 bolt block has more flex....
The 4 bolt block  does not flex... and so all rotating assy should be  FORGED! IMO ;D

I've had great  results with 2 bolt blocks under 6,500 rpm.

endless subject      :screwy:
Title: Re: bbc question???
Post by: 76 Bonneville on August 20, 2009, 09:07:30 PM

Question of tork or top end IMHO :P

I through my specs out there to give filterbiz something to reference from.
I forgot to say its turning 5800 rpms.
I've been told that jets like the longer strokes. If I were buying a motor and had a choice between a 427 and a 454, I would buy the 454.
Title: Re: bbc question???
Post by: 88CARRERA on September 02, 2009, 10:18:26 AM
I through my specs out there to give filterbiz something to reference from.
I forgot to say its turning 5800 rpms.
I've been told that jets like the longer strokes. If I were buying a motor and had a choice between a 427 and a 454, I would buy the 454.
thanks i went 454. at the machine shop now
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