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Discussion Starter · #1 ·
A pretty high winding big motor. What surprised me is the combination of 10.0 CR & a 273/[email protected] cam. Seems like the dynamic compression would be way low.

Is that someone here's? In other words is the engine builder or owner of the car a poster here?
 

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Discussion Starter · #3 ·
I didn't buy the magazine, but it was just his heads, not his motor or dyno test
 

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I have read and re-read that article in my issue of Car Craft. I can't read it anymore. All the drool is now obscuring the printed text!!

My wife says my motor is already built and I don't need them. And if I buy them she is leaving with the kids!! ....I sure am going to miss them.


Kaase Rules! Go Blue or Go Home!
 

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That was a great read.Two thumb's up.
I can't wait till someone makes an all out race version using these head's. HP number's should skyrocket.
 

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That was a great read.Two thumb's up.
I can't wait till someone makes an all out race version using these head's. HP number's should skyrocket.
Yeah, but if you're doing an all-out race hemi BBF, this probably isn't the head of choice.
 

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Jon K. has made 1000hp with these heads. and there is a u tube video of on here or at 429-460.com site.
and its a street car motor
 

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It would be cool to see what a max effort head would do on a race motor.just to see what it can do,just because.i'd like to see a set of these head's pushed to the limit just to see their all out performance level.Why not is the reason why.:D
 

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Discussion Starter · #13 ·
It would be cool to see what a max effort head would do on a race motor.just to see what it can do,just because.i'd like to see a set of these head's pushed to the limit just to see their all out performance level.Why not is the reason why.:D
this is probably getting close to the point that any more motor just makes them the wrong heads for the job:
http://www.460ford.com/forum/showthread.php?t=145132
 

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I do have a question in regards to this build. It states it has an intake lift of 0.790" with .024 lash and an exhaust lift of 0.787" with .026 lash. It also states it uses Manley 221443-16 springs. The specs for that spring:

Installed height pressure: [email protected]"
Open height pressure: [email protected]"
Rate lbs./in.: 535
Coil bind: 1.17"
Max valve lift: 0.730"

So, the question:

0.790" lift substract .024" of lash equals 0.766" actual lift.

The installed height of 1.95" substract 0.766" actual lift equals 1.184".

1.184" height substract 1.17" coil bind equals 0.014 clearance.

0.014" clearance? I thought you needed around 0.050" clearance. Is my math incorrect or is there tricks to get around this. I thought of increasing the installed height, but that would decrease seat pressure, and in the case of this engine, would that lead to early valve control loss?

Thanks for any clarifications,

Dave
 

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Discussion Starter · #15 ·
In higher end builds, it's common practice to push the coil bind limts. The coils hitting into eachother during spring surge would seem to act as a dampening factor.

Also Kaase is probably very very familiar with just how much deflection is going to exist in any combination of valvetrain parts.

There's a (controversial) example on Speed talk and Yellow Bullet right now of a guy who spent the money to Spintron his setup and found he was losing 15 degrees of valve open degrees at approx .200 cam lift @ 8500rpm, due to rocker and pushrod deflection with some very high rate solid roller springs.
I don't know what that equates to for total lost lift at max lift, but quite a lot. Maybe .080?
 

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I was just re-reading the original article and there is something that I just don't understand. I know the 834 horsepower sounds great. But the peak torque number seems pretty low to me. 674 lbs/ft at 5000 rpm. So with a pretty much "normal" bottom end and some monster flowing heads... Why is the torque peak so low? Wouldn't you want more torque for a drag race motor? I know some of the mud bog guys on here are into the high rpm's to get them through the mud but doesn't this torque number seem awfully low for that kind of horse power and cubic inches? What am I missing here? What don't I understand? Or is this due to how the cam is spec'd out? O.K. experts... Take me to school please. Thanks!!
 

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Discussion Starter · #18 ·
big cam, modest compression, and big ports, in that order...give you what you see.

.... @ 13.75:1 you'd see more torque by far. How much is a guess for me, some others on here are more expert, might be able to put a number to it.'

This is a classic example that a big hp number is just the ability to carry out the torque to a higher RPM... and that is in not way taking away from this combo, if you think about it.
HP is HP
 

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Dave,

I asked the same question of JK when I saw that he was using a .456 lift lobe on the Boss9 with the manley spring. Theory says thats .798 lift on a spring thats "recommended" for a max lift of .750.
John actually sent me this email back

"John, we normally run the 221443 spring with .456 lobe lift and 1.75 rockers. The spring coil binds at 1.140". The actual lift will be around .760. (with lash & deflection). I ran this in my Enginemasters Boss 511 and it worked fine. The math says no but in reality it works. The closer you get to coil bind, the better the spring works.

Not To Worry!, Kaase"

The maths dont work but he is the man.

Still , I am playing safe initially with My setup , a .440 lobe , and creap up on the spring by tightening up the lash?

John.
 
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