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Eugene Nahemow
05-10-2003, 03:21 PM
If you had these choices which would you choose to install in a 1970 Classic 18?

Small block 388 Dyno 470hp.
Big block 427 Dyno 540.

I am real concerned with engine hatch clearances.
I believe the big block will be about an inch taller. I do not want to modify hatch.

CDMA
05-10-2003, 04:11 PM
SBC. BBC is cool but with so much weigtht torque and rotational mass it disturbs the balance of the boat. A SBC is a great fit in an 18 and with 470 hp you should being doing just fine...

Chris

HP envy

MOP
05-10-2003, 06:09 PM
About 8-10 years back a buddy had an 18 with a 383 the one with dual quads it was awesome, I also think it will handle better with a small block. But that is better answered by the guys that have done the BB thing. I was told there is a 16 on Great South with a BB so who knows.

BUIZILLA
05-10-2003, 06:37 PM
SB

J

no brainer to me...

olredalert
05-10-2003, 07:42 PM
------I had one of the few big block/TRS X-18 boats built by the factory,and I found it to be too ass-heavy.Plane-off was slow.The boat heeled over severly in sharp turns.It was a seventy mile an hour boat bone stock,but I like my small-block/TRS Corsican more.Handling is just plain better.Now if you could whittle off enough weight to make the two equal I might feel different......Bill S.......ol red!

Moody Blu'
05-10-2003, 08:19 PM
small block ford wink or perhaps the big block cleavland wink

Eugene Nahemow
05-10-2003, 10:05 PM
The weight difference that I have calculated between the two seems to be around 200lbs.
The heads on the 427 are aluminum and I will be using CMI headers in either application.

The difference of HP wasn't too radical that I was favoring one over the other, but the torque on the 427 is another beast.

Chris, Why is the greater torque a problem?

Moody, I am not a big Ford fan. Except if it's a 427 side oiler in a Cobra. :D

The 427 is a Corvette engine that has been modified for marine use. I guess I can always put it in my truck. eek!