Aluminum or steel pushrods?

[pmriverrat]

1600 DP. Being built as a 1641. Stainless stock size valves. Stock rocker arms. Engle 100 cam. Valve load is 90# at opening and 200# at max lift. Professionally rebuilt heads. Stock crank so intending to limit revs to 5000 rpm. Looking for improved low end torque. Leaning towards steel pushrods. Anyone have experience to share? Edit to add. We are running high performance single valve springs.

[VW_Jimbo]

Keep the stock aluminum push rods. You have no reason for the steel ones. The steel is heavier and needs to be set differently, as the expansion rates are different between the 2 metals. You gain ZERO by going to steel and more work.
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Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[NJ John]

X2 on stock aluminum. Don’t forget solid rocker shafts.
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1973 standard, yellow, lowered, 3” narrowed front, 1600 blo-thru turbo w/single dell 15.4@86, so far
11.41 et buggy. Long gone
Let’s go O’s! Let’s go O’s!
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[pmriverrat]

I understand the differences in setup between steel and aluminum. With the increased spring loads because of the stronger springs and higher lift there will be more load on the pushrods. Steel pushrods are available locally. Was looking for someone who had experience with this combination. Appreciate the input so far.

[Zundfolge1432]

You need to ask this in performance forum, you’ll get better answers

[Glenn]

[bsairhead]

It strikes me funny that someone said that chromoly (steel) push rods are more work. Setting valve lash without feeler gauges is less work not more.

[Brian_e]

[Glenn]

[oprn]

If you are running a stock crankshaft and limiting RPMs to 5000 then there is no need for stronger springs and no need for different push rods and for that matter likely no need for the so called solid rocker shafts unless the valve train is noisy. In that case just remove the wavy washers and replace them with shims to get zero side play.

As for improved low end torque, you kind of blew that one with the cam change?
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We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age)

[Brian_e]

[SGKent]

In the late 70's early 80's. I built a stock 1600 for a bus that I used for many years. In spring and fall I took it out from Riverside to Lake Havasu once a weekend. A couple times it went from Riverside to Sacramento to visit family. Usually it was cruising at 75 - 80 mph in the middle of nowhere with the RV cam, back cut valves, and headers, dual carbs etc.. With the gearing on a bus that is like 5,500 - 6,000 RPM for hours on end. Totally stock crank, flat top pistons and stock pushrods and rockers. You can mentally masturbate yourself by putting whatever you want into your engine, but a well built stock engine runs and runs for 40,000 - 50,000 miles in a bus, more in a lighter car. And there is no need for killer valve springs either. Some good chrome silicon steel springs that are 150 - 180 lbs on the nose are fine. You'll need samples of each valve spring and a valve spring scale to test them. Other than I think Crower, the manufacturers won't share specs on their springs.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[pmriverrat]

The 70 and 200 pound figures were observed on a valve spring scale. The original valve springs were all soft. The core for this build was badly abused. Had to align bore it and cut the thrust. Oil leakage so bad most of the fins on the jugs were completely clogged.

[Brian_e]

The ramps and lift on YOUR cam are what determines what YOU will need for valve springs. Much more damage is done with too weak of springs then to heavy of springs. There are huge differences in cam lobes even if they look similar in the magazine ad. The w100 is an ancient grind, and known to be not real accurate.

Brian
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www.type-emotorsports.com

[oprn]

Yes I suspect ramp speeds do effect it. I am running a Web 86 cam with used stock springs and I have run it to 5800 rpm with no sign of valve float. Maybe it does have milder ramps.

As for the effects of the stock crankshaft, i just assume that anyone knowing they have a stock crankshaft is not going to be buzzing their engine into valve float rpms. That’s the only reason I said that.
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We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age)

[pmriverrat]

[quote="Brian_e"]

[modok]

How much should be taken off or extended depends on what YOU have changed.
Mostly....valve stem height vs how much machined off the head
The valve stem height on these isn't well standardized so that makes it impossible to have a universal spec.

So if you haven't changed anything then, time to decide what to change or figure out what's already changed.
If you install .040 lash caps then maybe the pushrods need to be shortened that much.

If you milled the rocker pedestals .040 then they will need to be shortened about .080, it's a two to one ratio for when you move the whole rocker shaft.
If you put on .160 radius swivel feet which extend the stem height, and .060 shims which go the other way, then that ends up .040 shorter

So, I'm guessing .040 shorter, + whatever was milled off the heads.
But that's a guess.

OE 1600 pushrods would be ok for what your doing but watch the travel in the rockers, aftermarket Smith Brothers or Manton, steel or aluminum is ok, the only thing not OK is cheap parts.

[Clatter]

I run steel pushrods on anything over stock.
No more remembering feeler gauges or fumbling with three hands adjusting valves.
Especially with swivel feet..

While some of the newer aluminum pushrods are perhaps better overall performers (lighter),
The convenience of steel pushrods makes them my choice in a street motor that will be driven.
While steel might be noisier when hot, especially overheated,
At start, or cooler temps, they are quieter than aluminum because of zero lash.

I just love steel. No going back for me.
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Bus Motor Build

What’s That Noise?!?

[modok]

And that's why they call him clatter

[RickS]