how can i get more power from my 454?

[the_blaze]

Well I pulled the motor today, the block casting number is 361959 and my heads Casting numbers are 336781. I will check out my pistons tomorrow to see what they put in there and also hoping to get the front torn down to get the cam information.

 

[the_blaze]

Ok I couldn't wait for tomorrow. Looks like the pistons are flat with small grooves for the valves. Looks like I am slowly gathering information on this motor. Still anxious to find any way to squeeze any extra power out of this pig without spending to much $

 

[nvrenuf]

Those 781 heads are open chamber which isn't helping compression but they are widely recognized as an excellent factory head. I would keep them unless you go to an aftermarket head.

Any numbers on the top of the piston?

Edit: this is what a factory piston looks like -

 

[the_blaze]

I didn't take the heads off and my view with the little camera is limited. But I didn't see the bigger center depression. They were perfectly flat except the two groves for the valves. Even those seemed pretty shalllow.

 

[the_blaze]

Are those heads worth having ported and polished?

 

[nvrenuf]

IMO are the head worth building? yes. From the factory they have small valves which you may or may not want to change depending on what the ultimate build / use is. The decision for port work and such, again, depends on the big picture. No sense spending a lot of money on bigger valves or extensive port work if this is a mild motor.

Need to identify the current pistons and cam then decide what you will or won't change before doing any head work.

 

[the_blaze]

So I pulled the timing chain and gear and didn't find any numbers on the camshaft. .. do I need to pull the cam the whole way out to find out what I have?

 

[steelwheels]

Yep...you have to pull the cam out to read the ID markings on the other end of the cam...sucks i had to do the same thing so i could have a better understanding of what i had in my engine build.

 

[TDAWG1]

Building My 454 here in a bit as well apreciate all the info. So excited for mine to get done should Be awesome

 

[76zimmer]

I say go for more compression...I run premium on my engine:
dyno 2000 says 550 tq and 460 hp torque curve is over 520 from 2000 to 4500 rpm...its a real nice powerplant for these trucks, especially when you want to hit the fast pedal often!


Quote:
[So my head guy emailed me the flow numbers for the 781 Oval Ports....

intake exhaust
.100--86 73 @28"
.200--169 128
.300--237 194
.400--285 216
.500--318 227
.600--319 227

Never had heads flow benched before....anyone know how these numbers look?

I just went to the best guy I know, and let him handle it....


by entering those flow numbers in my Dyno 2000 program, with small tube headers &mufflers, 800cfm dual plane intake, 9.4 compression, cam +4 advance....I get a peak of 470 hp, and torque peak of 550 @ 3500. ] end quote

Quote [Zim, here are the final numbers I get for your engine...

Number of Cylinders 8
Bore (in) 4.280
Stroke (in) 4.250
Connecting Rod Length (in) 6.135
Anticipated Redline (RPM) 5500
Gasket Volume (cc) 9.7
Piston Volume (cc) 23
Comb Chamber Volume (cc) 119
Deck Height (in) 9.800
Extra Quench Height (in) 0.005
Intake Closing(deg) 60
Boost Pressure (lbs/sq-in(psig)) 0
Volumetric Efficiency (%) 90

Outputs
Cylinder Volume (in3) 57.55
Swept Volume (in3) 6.52
Engine C.I.D. 460
Engine Liters 7.54
Bore/Stroke Ratio 1.07
Connecting Rod Ratio 1.53
Compression Height (in) 1.665
CFM Flow 659
Compression Ratio 9.82
Dynamic Compression Ratio 8.17

And yes it says 460, technically your bore is probably ~.005 thousands over that for piston clearance, and even if you change it to 4.281, then it rounds to 461 CID. Compression differences are negligable, .01 difference or something.

Also, for reference, in the gasket volume line, I was looking for the compressed volume of the gasket in cc, not the compressed thickness. Many times they list the compressed volume, if they don't I just calculate it based on the bore and thickness then on the side column gasket calculator in my spreadsheet. ] End Quote

my cam specs:

Comp Cams Mechanical flat tappet
rpm range 1600-6000
gross valve lift intake .553
gross valve lift exhaust .568
duration @ .050 intake 230
duration @ .050 exhaust 236
intake centerline 106
lobe separation 110

 

[the_blaze]

I just pulled my camshaft. On the very back it has MP K stamped. Then on the shaft it says EP2 then further up on the shaft it says D2 the 06 on the other side it says C2 in the middle and J5 towards the top. Anyone have any clue what this is?

 

[the_blaze]

Ok I finally got the specs on the camshaft that was in my 454. The shop oopsed and initially gave me the wrong info.
Intake : 204 .268 .455 Exhaust 208 .270 .459. So I guess that's pretty small. I'm still trying to figure out the best camshaft for a 1,400 to 5,400 range to maximize torque and low to midrange power. Thoughts and opinions would be great

 

[the_blaze]

Oh and it has a lobe spacing of 116.

 

[76zimmer]

Ok I finally got the specs on the camshaft that was in my 454. The shop oopsed and initially gave me the wrong info.
Intake : 204 .268 .455 Exhaust 208 .270 .459. So I guess that's pretty small. I'm still trying to figure out the best camshaft for a 1,400 to 5,400 range to maximize torque and low to midrange power. Thoughts and opinions would be great

I gave mine above....for the few that have rode in my truck, they can attest....it is HEAVY, and it MOVES!

 

[the_blaze]

Yeah I saw that it sounds like it's a beast! But also sounds like it's got more $ in it than my current budget allows

 

[the_blaze]

I gave mine above....for the few that have rode in my truck, they can attest....it is HEAVY, and it MOVES!

It sounds like you did a full blown performance engine. Is that right? Mine was just a factory style rebuild with a slightly better cam rods and valve springs. I'm trying to do what I can without a complete rebuild again. So I'm looking at a much better cam and springs and POSSIBLY roller rockers if I can find a set worth the money for the little gain. I do however like the specs on your cam. I think I will take those in to consideration. You wouldn't have a part number would you?

 

[76zimmer]

head work is about as important as cam selection I believe...but something in the .525lift and [email protected] duration should work real good with stock 781's.

BBC's love compression and cam, as always you should strive for matched components and your best bet would be to call Comp for some direction.

I have used a .523/.530 cam about a hundred years ago on an otherwise stock 1974 454, it responded very favorably...a dual plane intake, and 1-7/8 headers....no machining, no valve job, no upgrade on the springs...it really woke it up in a Monte Carlo I had.

 

[the_blaze]

Excellent suggestion. I'd love to do head work. It's all about finding a decent shop and not going way to far out on budget.

 

[the_blaze]

head work is about as important as cam selection I believe...but something in the .525lift and [email protected] duration should work real good with stock 781's.

BBC's love compression and cam, as always you should strive for matched components and your best bet would be to call Comp for some direction.

I have used a .523/.530 cam about a hundred years ago on an otherwise stock 1974 454, it responded very favorably...a dual plane intake, and 1-7/8 headers....no machining, no valve job, no upgrade on the springs...it really woke it up in a Monte Carlo I had.

On the plus side I already have a great dual plane intake a pretty large carb and the long tube headers . What do you know about carb spacers?

 

[76zimmer]

I think I would only use one on a 4x4 engine if it were Hi rpm or having carb temp transfer problems from the intake (you could use it as a themal break)

do you have a desk top dyno or similar?

I used one to evaluate some parts in my engine, it shows basic info as rpm range, hp and torque curves, when changing parts it shows gain or loss of those parts etc. Helpful tool I think.