Pushrod comparisons

JOHNBOY said:
Did they come with the cam? If they did they are like mine .125 wall. I have bent rockers, snaped bridges, snaped rocker shafts and the push rods are still straight as can be.
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Yes it was all matched with all the other engine components...
 
Johnboy, did you have a failure in your valvetrain?


Our 3/8 .095 wall thickness pushrods will deflect much less than the factory units, and if there is a gear failure they will still act like a fusable link they will bend.

Our7/16" .168 wall thickness pushrods used on our extreme duty sets will not bend in the same instance. THey are rock solid.

Zach
 
I had a failure for the second time in my valvetrain. Its a Dmax. My push rods are fine. Both failures where caused by the same issue I beleive. I overlooked something the first time I had a failure. The second time I broke it I looked much harder and enlisted help. I think I have it handled this time but time will tell.
 
GOT-Torque said:
Here you go...

pushrods.jpg
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looks like my smith brothers push rods
 
jlibert said:
Zach,

Have you dyno tested these on a 500+ hp truck (back to back without any other changes.)


I'm just shy of 700 hp, and I picked up a set of your pushrods last year. I haven't put them in because I convinced myself that they wouldn't really make a difference.

If you don't have dyno comparisons, I could possibly do back to back (before/after) dyno on a dynojet 248.

-jp
Click to expand...

^^ZACH^^


thanks-
 
As of now I have done package (cam, springs, pushrods)dyno comparisons with different packages. I am always interested in seeing customers dyno sheets for feedback.
What cam and springs do you have?

I am doing some testing on some new products now. I am looking forward to sharing all of the info. with you.

Zach
 
Hamilton Cams said:
As of now I have done package (cam, springs, pushrods)dyno comparisons with different packages. I am always interested in seeing customers dyno sheets for feedback.
What cam and springs do you have?

I am doing some testing on some new products now. I am looking forward to sharing all of the info. with you.

Zach
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Thanks for the response. Stock cam (for now), your springs(installed), and your pushrods (still in the box).

I'll talk to eric and reb at browns and see if they have any dyno time available soon.

Would you expect to see any gains on a dyno from pushrods alone?
 
Yes, but negligable in your case. The ramp rates on the factory camshaft are slow and lazy. The aggressive ramp rates found on performance cams will deflect a factory pushrod much more so the gains would definately be higher over a stock pushrod. Also if you were running the 4000 rpm programming, you would see a greater benefit.

Zach Hamilton
 
Hamilton Cams said:
Yes, but negligable in your case. The ramp rates on the factory camshaft are slow and lazy. The aggressive ramp rates found on performance cams will deflect a factory pushrod much more so the gains would definately be higher over a stock pushrod. Also if you were running the 4000 rpm programming, you would see a greater benefit.

Zach Hamilton
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Thanks for the quick response. I'm right at 700hp, and run the TNTR tune.

I see 4000 rpm continuous when pulling.
 
I have never done any testing with your exact combination. Let me know how it goes. There are so many potential combos it is hard to test every scenario.

Zach Hamilton
 
Zach,
I am trying to attach the dyno sheet for the run at Buda on April 4 on the 2001 Ram. Thanks for the build. I need to correct the torque converter issue and try to reach better numbers. The run was EXCITING!!!!!
 

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That was just a shakedown run with a mild tune. I will open her up for you next time you come in.

Zach
 
Hey guys I did some math today as I am stuck in a hotel in the Philippines and have absolutely nothing else to do.

The following equations are for average cylinder pressure not peak which would be much higher for short moments. At the points in which the pushrods will be affected average is more precise such as exhaust opening. Also for horsepower the equation calls for BHP which is at the flywheel. For this I assume any reading obtained at the rear wheels will have a 16% loss in the driveline. For the equation to see how your cylinder pressure lines up look at the second number whiich is a derivative of the BHP. Also a lot of the trucks I have seen peak at around 2600rpm
792,000xBHP/C.I.x rpm=avg cyl pressure

325hp at crank = 273 at the wheels= 275psi
600 hp at crank=504 at wheels= 509psi.
750=630hp at the wheels=636psi
1000=840hpat the wheels=848psi
1200=1008hp at the wheels=1018 psi

now lets figure load on the pushrod factoring 2.65 sq. in. of valve face surface area

275 hp=273psi x2.65sq in=728lbs +220lbs spring press. X1.34 exh. rocker ratio is 1271lbs.

504hp= 2102 lbs force on pushrod

630= 2553lbs on pushrod

1000=3306 lbs on pushrod

1200= 3909 lbs on pushrod

Now here is where the rubber meets the road. Factory pushods are rated at 1794 lbs, motorsport supply 1982 lbs. Hamilton 3/8" 2064 and Hamilton 7/16" 4035. over 500rearwheel horsepower you at least need the 3/8 .095 wall over 630Rwhp you really need to jump to the 7/16" .120" wall. If you don't the pushrod bends first then opens the valve. It delays the valve opening which reduces spool and power. If you are a low budget street racer you will not notice much difference in spoolup or major power but if you are racing or sled pulling and want to make sure you don't snuff that big charger down the line, use a better pushrod to open the exhaust on time at full power. It will help the chargers stay lit by not retarding the exh opening.
 
so what is my advantage with yours versus a 150.00 set of rods from Smith Brothers Push rods ? they offer a ton of 4130 wall thicknesses . what are the cost of yours? i am in the market as we speak and would like to get a set soon.
 
zack ihave a 12v with cr cam and cr lifters what push rod will work for this set up stock push rod ball is to small
 
When it is all said and done I have done the research and make the best product I can for a fair price. I even have some top names in the sport grind my name off of them and sell them as their own for about double what I do.

The best thing for you to do is to use my research to figure out what you need and then go find the cheapest. If price is your main focus mine should not be considered. Look at page one and look at the specs of the black pushrod for better info. Some have said those look like Smith bros.


If you have 24v tappets, although you don't have to, you can order 12v rods from us with 10mm balls on the end, so that everyting is perfect.
 
I have seen a lot of people do it with good results but if you don't mind and extra $50 then we can have a set made that is correct for a 12v with CR tappets.

Zach Hamilton
 
thanks. you give real good imformation on all your parts who do i contact to get this done and what is total cost
 
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