[mpmsmuscle]

I am building a 455 stroker and need some advice on HP projections and camshaft selection. I will be using a hydraulic roller and have been advised to use solid roller lifters. My target hp goal is 650 to 660 hp, pump gas, power brakes with street manners in a 3900 lb car with a 4 spd M-22 transmission. 73 455 block bored .060 over with zero deck. Compression is 10:6 to 10:8.1. I have attached head flow numbers and a suggested camshaft grind. This car will be mainly driven on the street.. What advice or suggestions do you have?

73 455 block bored .060 over with zero deck height
474 stroker
Ohio forged 4.25 crankshaft
Weisco flat top pistons 10cc valve relief
Crower 6.700 sportsman rods
Kauffman High Port heads
Northwind 4500 intake
Pro form 850 carb
Doug’s headers
12 bolt GM reared with 3.73 gears
Muncie M-22 rock crusher transmission
MSD ignition

Flow bench results

Lift Int. Ex. Int/Ex ratio
.200 134 134 100%
.300 201 186 92%
.400 260 227 87%
.500 306 255 83%
.600 332 265 79%
.700 342 271 79%
.800 350 277 79%

Recommend Custom camshaft grind. Hydraulic Roller

254/262 duration @ .050
.570/.570 lift with 1.52 r
.627/.627 lift with 1.65 r
111 LSA

Solid roller lifters with .007 lash
200 lb on the seat

[4dblnkldude]

One hell of a build. Is this going in the bird? I am not experienced enough with cams to give a recommendation. Its gonna be a beast I'm 100hp less and not really sure I would want more.

[mpmsmuscle]

Going in the 69 Judge!!!

[Jay S]

That combo of parts appears to be more in the lower 600s HP to me with the high ports. Should be a blast to drive though.

Run as much valve lift as you can afford.

[tom s]

Your set on solid roller lifters get a tight lash street roller cam in the same specs.No reason to use something not intended.JMHO,Tom

[Formulajones]

Yep, agree with Tom, if you want solid roller lifters, I'd just go for a solid roller stick.

That hydraulic roller cam is eerily similar to the same cam that Kauffman spec'd for a 455 (463ci) I put together for dad years ago. Same .050 duration and lift but Jeff did it on a 110 LSA at that time for what ever reason. Used Kauffman 330 cfm heads he did at the same time. Just an FYI, it didn't hit 600hp on the dyno, but it did make over 600 ft lbs. of torque.

Fantastic engine on the street though, dad had a ball driving that around.

[equidr]

Some of the parts you have listed don't appear to be compatible. The Northwind 4500 is a dominator intake and you have a 4150 carb listed. Hood clearance may be an issue with the high ports and that intake leaving little room for an air cleaner that will flow well enough to feed that engine combo. The Muncie will have difficulty living long behind that much power with spirited driving. With that being said it will be a hell of a lot of fun. My last build made over 500 hp and just under 600tq and it was difficult to make use of all the power on the street.

[chuckies76ta]

What mods are being done to the block? I think a Hydraboost unit will be best for braking system. At 1.5 R/R isn't that a little small for what the heads flow? Wouldn't you want to be into the .600 to .700 lift? As mentioned on intake, the 4150 Northwind should work fine port matched. Maybe a 950 carb. I made close to 600hp and torque with KRE D- port heads with 1-3/4" headers, a Torker2, and a 950 Quickfuel. I would also do the solid roller with tight lash. I'm just a novice here. Others on here have way more knowledge and experience.

[Steve C.]

Here is some insight regarding a reasonably good example of a camshaft selection for the projected 650 horsepower goal.

This build was 463 cid using a 4.210" stroke and 6.625" rods.

It used a Custom solid roller cam with 265/270 @.050" / 0.691" lift / 110 LSA. The cylinder heads were similar in that they both were rated 340 cfm at 0.700" lift.
With a 2.190" intake valve. Spring pressure was 230 lbs on the seat. The compression was 11.4:1 in conjunction with 'heart shaped' combustion chambers.

Quite a bit of difference than the 254/262 duration @ .050 mentioned here. And note the valve lift was up near where the heads were rated at.

It too had a carb / intake combination that was cobbled together, but this with a 1050 Dominator carb using an adapter to mount it on a 4150 Victor intake.
Headers were a small 1.750".

The result was 650.4 hp at 6300 rpm (0.437 bsfc) and 596.5 ft.lbs. torque at 4900 rpm.

As typical this post does not represent any endorsement of the combination here, and offered for general interest only.
The engine was dyno tested, but noting the obvious in that the results with different types of engine dynos, test cells and operators can vary all over the map.
Also noting the stroke and rod length difference will alter things a bit.



.

[25stevem]

With the flow of those heads only need to run .600” to get to your target hp you goal, so a custom hydro roller can be used, but that goal will not take place with a 850 cfm carb, you need 1050!

Also this build when done will shred that 22 trany in short order!

[Steve C.]

For interest I'd like to see a dyno proven 4.250" stroke 650 hp combination with cylinder heads rated 330 cfm at .600" lift using a .600" lift hydraulic roller cam.
Or using a formula suggesting the same heads and with net cfm airflow delivered at the valve thru the carb, intake manifold and cylinder head. Not the cylinder head cfm flow itself.

[OCMDGTO]

Nice build and I'm interested in the results.

[mpmsmuscle]

I was thinking the cam was a little small with the 1.5 r rockers also. Butler flow tested the heads and also spec’d the cam for me, told me no problem with 650HP!!
I thought a good rule of thumb is to select a cam that will lift the valve 20 to 25% past its peak flow point. The reasoning behind this is, if you lift the valve only to its peak flow point, then the valve only flows best when it’s wide open. The cycle is brief and would only happen once per stroke. So to benefit from your peak flow the most, you want to lift the valve past its peak. That way the valve will pass its peak flow twice in the cycle. The result is more flow during the opening and closing event!!
I’m not sure if this is correct or not? It’s just what I have read. That’s why I made the post. I was thinking something more like 640/640 lift with 1.65 rockers.

[mpmsmuscle]

Thanks that what I was thinking also. Something like 640/640 lift with 1.65 rockers.

[ta man]

Street car . I would go less duration and get the lift up in the high .6's.
I have less head flow but my gross lift is .660..with a mild 235/245 duration cam.
I think if your in the 245/255 range with a similar lift that should get er done.
Car will be handful with a stick.

[n20ta2]

Not sure if you already have the intake or not but might want to order now, kauffman has been backordered a couple months now already

[mpmsmuscle]

Thanks, I have the intake already. Just need to hone in on camshaft and lifters.

[74Grandville]

not sure how accurate, but fun to look at.

[AG]

My race car in my sig with a 461 went 10.18 and weighed 3525#, the horsepower calculator says 660 Hp for that. Same top end and cam in a 499 ci plus 28 lb and it goes 10.0 at 134.3 mph now. Heads are KRE CNC ported old style Eddy heads that supposedly flow up to 335 cfm. Both motors use a Victor/dominator set-up. This is an example of what a certain size cam will make for Hp in a motor similarly sized as yours. The cam I use is a solid roller so the duration will be reduced by at least [email protected]" to compare to a HR cam.

[mpmsmuscle]

So are you saying use a solid roller cam? What lift and duration cam are you using in your similar build?