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tmdog
03-16-2011, 11:37 AM
Last season the 383 was dependable but lacked power. Gps mid 70's. Pulled engine and sent short block to machinist for freshening. Reset cam and bored block to .040 over, also replace bearings. Needed valve job ( valves hammered into seat), likely valve float. Mind you, only 30-35 hrs on eng.

Dyno time arrived and did 12 pulls. The final pull advanced timing to 36* total and eng. came alive. Results below.

Just Say N20
03-16-2011, 12:22 PM
Wow! You must be pleased.

Nice torque curve.

maddad
03-16-2011, 01:00 PM
Awesome power from a 385! Care to share some of the specifics?

Tidbart
03-16-2011, 02:40 PM
Just curious, where would you set a rev-limiter on a motor like this?

5500 with flattening HP and declining torque?
5000 with slightly declining torque and increasing HP?
4600 with max torque and increasing HP?
Something else? What would be the factors you look at when making this determination?

I would imagine, although you can get higher Hp with higher rpms, you consider longevity as part of the equation.

Bob

Pismo
03-16-2011, 03:17 PM
Nice T curve. What boat?

tmdog
03-16-2011, 07:12 PM
Thanks for the positive comments.
Wow! That was the first word from my mouth also. The T curve was of utmost interest to me in the eng. build. Thanks to Bullet cam who chose cam to match the AFR heads.
If I was to set a rev limiter I would set it at 5800. A couple of major factors should be considered. Prop pitch and longevity of a Alpha SS drive. Sure, I intend to visit 5800 which will be infrequent and swing no larger than a 25p Hydro OT. I hoped for a strong power plant which I think I have and will be happy with a limit of 70. It is also nice to say " I almost have a 500/500".
The build. Block, O decked, SRP 16cc dished pistons for a comp. ratio of 9.7 and 6" rods. AFR 195 Elim. alum. heads, Edel. Rpm airgap intake and a 750 holley. Prem. fuel only. Stuffed in a 18 Classic.
AFR heads are pure art work.

BUIZILLA
03-16-2011, 07:27 PM
excellent choice of parts :wink:

Pismo
03-16-2011, 09:02 PM
How's your quench?

SamIam
03-16-2011, 09:04 PM
Nice motor.
Thinking of the same engine for my 16

tmdog
03-16-2011, 10:25 PM
How's your quench?

Tight, .038 Felpro gasket.

Want to thank Mr. Fix for his help and advise.

tmdog
03-16-2011, 10:28 PM
excellent choice of parts :wink:

Thanks Buiz. Getting a compliment from you Fl. boys is tough.:yes:

mrfixxall
03-18-2011, 12:30 AM
Tight, .038 Felpro gasket.

Want to thank Mr. Fix for his help and advise.


Any time jim!! Now let's hope it warm's up real QUICK so you can get a video of that little monster in action for us..:kingme:

Sweet Cheekz
03-18-2011, 07:39 AM
Cant wait to see how this and an ss runs in a 18 instead of a 16
Well done
Parnell

pipnit
03-18-2011, 09:29 AM
Congrats, nice work! I'm in the process of building a similar motor but I have a constraint, I can only get 87 octane. Out of curiosity, what octane gas are you running in the boat? Again, nice work!

The Hedgehog
03-18-2011, 09:32 AM
Nice numbers. Congrads!

tmdog
03-18-2011, 02:04 PM
Congrats, nice work! I'm in the process of building a similar motor but I have a constraint, I can only get 87 octane. Out of curiosity, what octane gas are you running in the boat? Again, nice work!

The dyno guy suggested premium fuel only. The same fuel I ran before teardown.

tmdog
03-18-2011, 02:13 PM
Cant wait to see how this and an ss runs in a 18 instead of a 16
Well done
Parnell

I followed your build on your sweet rideing16.

Before teardown with 2 cyl. barely functioning ( 76% and 45% leakage) boat ran mid 70 w/ the SS.:shocking:

Just want a reliable ride so as to quit turning wrenchs during the season.

younger
03-18-2011, 02:14 PM
Great combo! Those AFR heads are the ticket. My Motown 415 is going to have a set of the 210's at some point hooked to the bh 16. You have the power to fly!