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Discussion Starter · #1 · (Edited)
My Engine is nearly complete,and with all the duckey's I have invested in this project and with still more to go, I don't think that I will have any left on the table for a Dyno session.
So I would like to hear some estimates on where You think the HP will be at.
I know it will be a rough guestimate, But some where in the ballpark will be better than outside the fence!

Allrighty then here are the specs.

489 c.i.d. BBC Full roller motor.

.030" over bore

Scatt 4340 forged crank, 4.25" stroke

Splayed main caps /w ARP main studs

Eagle, 6.135" forged H beam rod's

SRP forged pistons/17cc dome volume

Block has been zero decked

Bullet Racing Cams solid roller cam

Morel pressure fed solid roller lifters

Cloyes hexadjust double roller timming set

AFR 325cc aluminum heads/116cc chamber/ ARP head studs
(Head specs and flow chart. http://www.airflowresearch.com/bbc-325cc-c-1_97.html)

Crane gold rockers,1.8 int.,1.7 ex

Edelbrock TR2 tunnelram

two 600 cfm holley carbs

As good as the heads are I had a little more done to them. A little more port work to smooth out a couple bumps and a little shave to get a little more compretion. 10.29-35:1, not sure where the heah mill puts the chamber size?
I also ordered the AFR intake gaskets which match the head's intake ports much better than the felpro and the intake has been portmatched to the head's.

Here is the Cam card with all the cam specs .

So please give Me You'r best estimates....Hal




Here are a few pics of the Mill before the heads and intake were asymbled.







 

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Resident Ford Nut
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10,033 Posts
I bet you get 400hp :D
I'd bet on it too......

Did I miss the compression ratio :)bulb

What rpm range do you plan on running it. Needs more carb if your going over 5,500 and want everything you can get out of it :)bulb

S CP :D
 

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Discussion Starter · #5 ·

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Amber Racing Services
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Better get more than 400!:mad:
I just wanted to be conservative ... I'm not usually a betting person unless I know I will win.

I'd win that bet. :D

I'm guessing with what you've posted around 650-675?

The largest variables that effect it are your AFR's, .720 lift cam, intake manifold & carbs. Your CID is fixed ... so the hard components are what they are.

Getting your 489 to release the HP it contains is the whole trick, therefore you have to play with the variables. It takes time to figure out how much this or that you need to allow the engine to breathe properly.

Have fun.
 

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i'm back!!
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afr flows those heads at 4.600 bore, ur .030 over stockbore is gunna hurt flow bad,probably kill 50 cfm or more long stroke with short rods..bad rod angle. Good cam choice, tr2? and ur carbs not so much.. but im just a pickey bastard...lets see....I guess about 660 or so with good torque....:D

Nice solid motor...looks good..:)devil
 

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just a ski boat with bark
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My Engine is nearly complete,and with all the duckey's I have invested in this project and with still more to go, I don't think that I will have any left on the table for a Dyno session.
So I would like to hear some estimates on where You think the HP will be at.
I know it will be a rough guestimate, But some where in the ballpark will be better than outside the fence!

Allrighty then here are the specs.

489 c.i.d. BBC Full roller motor.

.030" over bore

Scatt 4340 forged crank, 4.25" stroke

Splayed main caps /w ARP main studs

Eagle, 6.135" forged H beam rod's

SRP forged pistons/17cc dome volume

Block has been zero decked

Bullet Racing Cams solid roller cam

Morel pressure fed solid roller lifters

Cloyes hexadjust double roller timming set

AFR 325cc aluminum heads/116cc chamber/ ARP head studs
(Head specs and flow chart. http://www.airflowresearch.com/bbc-325cc-c-1_97.html)

Crane gold rockers,1.8 int.,1.7 ex

Edelbrock TR2 tunnelram

two 600 cfm holley carbs

As good as the heads are I had a little more done to them. A little more port work to smooth out a couple bumps and a little shave to get a little more compretion knocking on the door of 11:1
I also ordered the AFR intake gaskets which match the head's intake ports much better than the felpro and the intake has been portmatched to the head's.

Here is the Cam card with all the cam specs .

So please give Me You'r best estimates....Hal
Well with the info you gave 4.250+.030 bore x 4.25 stroke, zero deck, 17cc dome pistons and 116cc cylinder chambers I see your compression at 10.3:1.

With you rod stroke ratio at 1.44 (6.135/4.25) I see this being a good low end motor but I think the top end may not be as good.

I'm guessing 630hp around 6400rpm.
 

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Well, being I know what the heads(before they were worked over) cam and t -ram with carbs made on a 496.. Which was 710hp @6300, I would guess, with alittle less CID and a shorter rod in the 650 - 685 hp range.
 

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cubes are smaller than my 502, but cam is relatively similar maybe even a little bigger. you've got a point more compression, and it is stroked 1/4". I'm going to go out on a limb say 700hp+. Those carbs are going to hold you back on top end power but torque will be around 650 ft/lbs. More carbs and you'll be closer to 750 hp
 

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All of you guys know your stuff! And I know very little so my guess is 688 HP. I hope it's more, and should push your boat very well! Man you are getting close to testing it out! Good luck! WT:)devil
 

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mo balls than $cents$
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i'm assume'n:D this ain't a mark 4 block guys, he may have gotten his cubes with a bigger piston than mark 4 and the 4.25 stroke;) still could've went longer.
 

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My 565 with a similar parts list topped out a 807 @ 6200, but still pulls hard past 7K, and that is with two basically stock Holley 600's. Reason I went with the small carbs was for throttle response, I know I'm giving up some on the top end, but this was built strictly as a lake boat.

I'm much too old to go for a swim and try to heal, and besides I gave my word to the little lady.

Your cam is slightly advanced compared to mine if it was installed as shown. I have a 110 LSA and no reversion at all, but I did shim the spring in my T valve so water does not flow till 2K, and stops before it returns to idle.

I think more than anything the small bore is your biggest restriction. The difference between 4.5 to 4.6 on the bore will change the flow significantly, so you can imagine what the diff. is between your 4.28 and 4.6.
 
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