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View Full Version : How much HP does a stock 460 have?



THEPISTONHEAD
04-18-2007, 02:13 PM
Im curious for insurance sake. I know there are different 460's but for the sake of general 1970's and early 80's boats....how much would a bone stock marine 460 pump out? 290hp...320hp....less......more?
Thanks as always guys!
Jason

dmontzsta
04-18-2007, 02:29 PM
That is a tricky question, they are all over the place in terms of hp/tq.
I would guess any marine 460 (stock) makes around 320-360hp.

Coded-Dude
04-18-2007, 02:33 PM
What he said

IMPATIENT 1
04-18-2007, 02:38 PM
don't know but feels like ALOT more than stock bbc:D

4trax
04-18-2007, 02:46 PM
My first boat was a 77 Baja jet with a 460 and the factory stickers were still on valve covers that said 330hp. Along with some other info.

THEPISTONHEAD
04-18-2007, 03:08 PM
Thanks all!

SmokinLowriderSS
04-18-2007, 03:46 PM
My dad'sw Indmar book that came with his/my Taylor rated the 460 at 320 HP. The 330 HP 454 only made about 280 to 290 from what I have learned, I'll bet the 460 was similar.

sstjet
04-18-2007, 04:47 PM
smokin is right on. We had a 79 wreidt with a stock 460 and had the original owner manual from indmar showing 320 hp.

IMPATIENT 1
04-18-2007, 05:02 PM
Im curious for insurance sake. I know there are different 460's but for the sake of general 1970's and early 80's boats....how much would a bone stock marine 460 pump out? 290hp...320hp....less......more?
Thanks as always guys!
Jason
change the timing chain to a 1970 model tru roller, small 500 lift cam, and rpm intake and you have over 400hp really cheap;)

LakesOnly
04-18-2007, 05:57 PM
The Ford Marine-issue 460's HP varies from brand to brand, sticker to sticker. Generally, the Hardin-Marine 460's were rated at a realistic 320-330HP. This was essentially a bone stock 460 with truck/CJ rods, fully grooved main bearings, 24cc cast dished pistons, D3VE heads with special valve springs and/or spring cups, Ford Motorsport M-6250-A460 cam and the D0OE-9425-C iron CJ intake manifold and a Holley carburetor. Compression ratio just below 8:1
The King Cobra 460's that came out in the mid-1980's had the addition of forged flat-top pistons which increased compression ratio to about 9.2:1. I forget the exact HP rating but I think it was somewhere from 340 to 360HP.
LO

THEPISTONHEAD
04-18-2007, 06:26 PM
change the timing chain to a 1970 model tru roller, small 500 lift cam, and rpm intake and you have over 400hp really cheap;)
Thats what im talkin bout' !!!!!!

LakesOnly
04-18-2007, 06:50 PM
change the timing chain to a 1970 model tru roller, small 500 lift cam, and rpm intake and you have over 400hp really cheap;)The factory 460 marine cam specs are already at .500 lift.
The M-6250-A460 Hydraulic Flat Tappet Cam = 0.493" Intake, 0.502" Exhaust and 216°@.050" Intake, 220°@.050 Exhaust.
These factory 460 marine engines benefit greatly from head porting and a compression ratio increase (if you have the dished pistons). A real popular swap for our customers is to R&R the D3VE heads for ported D0VE heads with 1.8 ratio roller rockers...100HP gain is possible even when keeping the thru transom exhaust.
LO

Duane HTP
04-18-2007, 07:42 PM
Dominator rated their 460 Ford and pump package at 195 usable HP at the pump shaft. This fit into the insurance formula very nicely.

pw_Tony
04-18-2007, 11:32 PM
I wonder why my Cam in my boat is only 'bout a .445" lift or so? Is that a normal RV cam?

jetboat
04-19-2007, 05:56 AM
growing up in california and boating in the 60's and 70's,moat of the builders i was told reduced the horsepower ratings so the insurance people would be appesed.on the title to my 79 taylor it states 250hp.and the old valve covers said 325hp from hardin marine.

IMPATIENT 1
04-19-2007, 06:04 AM
The factory 460 marine cam specs are already at .500 lift.
The M-6250-A460 Hydraulic Flat Tappet Cam = 0.493" Intake, 0.502" Exhaust and 216°@.050" Intake, 220°@.050 Exhaust.
These factory 460 marine engines benefit greatly from head porting and a compression ratio increase (if you have the dished pistons). A real popular swap for our customers is to R&R the D3VE heads for ported D0VE heads with 1.8 ratio roller rockers...100HP gain is possible even when keeping the thru transom exhaust.
LO
i measured the stock cam that came outta me oe taylor sj mill and it only had maybe 440-450 lift. the reason i suggested the 500 lift cam is becuase the oe cam is a smog cam and once you install the "good" timing chain and try to degree the oe cam, ya damn near gotta retard it 4degrees to get it back to perfect 0 which defeats the purpose of a pre-smog chain i thought. i stuck in a summit racing 505 lift cam ,pre-smog chain, rpm intake, degree'd the cam and it was perfectly centered, which i found impossible to do with the stock cams.

Amm
04-19-2007, 07:16 AM
This is what I have, http://www.harmanmarine.com/newsite/Library/pp/04.pdf
It says 330 hp.

Sanger Jet
04-19-2007, 08:30 AM
To much HP for some and Not enough for others:idea: :eek:

IMPATIENT 1
04-19-2007, 08:54 AM
To much HP for some and Not enough for others:idea: :eek:
is there every enough??:D i built a blown 475bbc, its gonna be strong and all i can keep thinking about is how i can get more hp before i stick it in the boat:devil:

BADAXE
04-19-2007, 09:07 AM
This is what I have, http://www.harmanmarine.com/newsite/Library/pp/04.pdf
It says 330 hp.
This is what we got 30 years ago when we picked up our brand new 1977Mach1 Mini Cruiser.

dmontzsta
04-19-2007, 09:25 AM
don't know but feels like ALOT more than stock bbc:D
Doesnt chevy pay you? :)
...if they only knew.:D

IMPATIENT 1
04-19-2007, 09:42 AM
Doesnt chevy pay you? :)
...if they only knew.:D
yes sir, i'm a gm master tech and foreman at a chebby dealership. i know whats up, bbf's rule:D

Ken F
05-10-2007, 06:41 PM
yes sir, i'm a gm master tech and foreman at a chebby dealership. i know whats up, bbf's rule
Boy, that right there is "Signature" material. I don't care who you are!

camoman
05-10-2007, 08:03 PM
is there every enough??:D i built a blown 475bbc, its gonna be strong and all i can keep thinking about is how i can get more hp before i stick it in the boat:devil:
Methanol:confused:

IMPATIENT 1
05-11-2007, 08:27 AM
Methanol:confused:
you buy me a hat injection system and i'll go that way:D :D :D