Author |
Message |
pmriverrat Samba Member
Joined: October 09, 2021 Posts: 92 Location: West Michigan
|
Posted: Sun Jan 22, 2023 3:40 pm Post subject: Aluminum or steel pushrods? |
|
|
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.
Last edited by pmriverrat on Sun Jan 22, 2023 5:02 pm; edited 1 time in total |
|
Back to top |
|
|
VW_Jimbo Samba Member
Joined: May 22, 2016 Posts: 9966 Location: Huntington Beach, CA
|
Posted: Sun Jan 22, 2023 4:24 pm Post subject: Re: Aluminum or steel pushrods? |
|
|
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. _________________ Jimbo
There is never enough time to do it right the first time, but all the time necessary the second time!
TDCTDI wrote: |
Basically, a whole bunch of fuckery to achieve a look. |
67rustavenger wrote: |
GFY's Xevin and VW_Jimbo! |
|
|
Back to top |
|
|
NJ John Samba Member
Joined: September 21, 2007 Posts: 2223 Location: HdG, MD & NJ
|
Posted: Sun Jan 22, 2023 6:48 pm Post subject: Re: Aluminum or steel pushrods? |
|
|
X2 on stock aluminum. Don’t forget solid rocker shafts. _________________ 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!
https://www.youtube.com/@AirSpooledGarage |
|
Back to top |
|
|
pmriverrat Samba Member
Joined: October 09, 2021 Posts: 92 Location: West Michigan
|
Posted: Mon Jan 23, 2023 7:14 am Post subject: Re: Aluminum or steel pushrods? |
|
|
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. |
|
Back to top |
|
|
Zundfolge1432 Samba Member
Joined: June 13, 2004 Posts: 12467
|
Posted: Mon Jan 23, 2023 7:36 am Post subject: Re: Aluminum or steel pushrods? |
|
|
You need to ask this in performance forum, you’ll get better answers |
|
Back to top |
|
|
Glenn Mr. 010
Joined: December 25, 2001 Posts: 76936 Location: Sneaking up behind you
|
|
Back to top |
|
|
bsairhead Samba Member
Joined: October 08, 2008 Posts: 3578 Location: viroqua wi.
|
Posted: Mon Jan 23, 2023 10:35 am Post subject: Re: Aluminum or steel pushrods? |
|
|
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. |
|
Back to top |
|
|
Brian_e Samba Member
Joined: July 28, 2009 Posts: 3291 Location: Rapid City, SD
|
Posted: Mon Jan 23, 2023 10:48 am Post subject: Re: Aluminum or steel pushrods? |
|
|
pmriverrat wrote: |
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. |
I use lots of stock aluminum push rods cut down with HD single springs and up to 37mm intake valves, and cms similar to the w100. They work great, and are WAY better quality than any set of steel rods that cost less than $100/set.
The aluminum are much lighter, which means they will work better if you are getting near the limits of your springs.
Brian _________________ www.type-emotorsports.com |
|
Back to top |
|
|
Glenn Mr. 010
Joined: December 25, 2001 Posts: 76936 Location: Sneaking up behind you
|
Posted: Mon Jan 23, 2023 10:49 am Post subject: Re: Aluminum or steel pushrods? |
|
|
bsairhead wrote: |
Setting valve lash without feeler gauges is less work not more. |
_________________ Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"
Member #1009
#BlueSquare |
|
Back to top |
|
|
oprn Samba Member
Joined: November 13, 2016 Posts: 12730 Location: Western Canada
|
Posted: Mon Jan 23, 2023 10:50 am Post subject: Re: Aluminum or steel pushrods? |
|
|
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? _________________ 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) |
|
Back to top |
|
|
Brian_e Samba Member
Joined: July 28, 2009 Posts: 3291 Location: Rapid City, SD
|
Posted: Mon Jan 23, 2023 10:57 am Post subject: Re: Aluminum or steel pushrods? |
|
|
oprn wrote: |
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 |
HA!!! This is wrong. The stock crank has nothing to do with valve springs.
He is running a w100, and it WILL need better springs. I had a similar setup in my first bug, and I launched a push rod out of its cup peeling out in the rain. I didn't even rev it that high, but I did get to walk back home and get tools. Yes, the valve lash was correct.
He also has a bigger than stock cam, so he will need to set up the rocker geometry, and most likely cut down the push rods.
Brian _________________ www.type-emotorsports.com |
|
Back to top |
|
|
SGKent Samba Member
Joined: October 30, 2007 Posts: 41031 Location: Citrus Heights CA (Near Sacramento)
|
Posted: Mon Jan 23, 2023 11:06 am Post subject: Re: Aluminum or steel pushrods? |
|
|
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. _________________ “Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin |
|
Back to top |
|
|
pmriverrat Samba Member
Joined: October 09, 2021 Posts: 92 Location: West Michigan
|
Posted: Mon Jan 23, 2023 11:27 am Post subject: Re: Aluminum or steel pushrods? |
|
|
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. |
|
Back to top |
|
|
Brian_e Samba Member
Joined: July 28, 2009 Posts: 3291 Location: Rapid City, SD
|
Posted: Mon Jan 23, 2023 11:42 am Post subject: Re: Aluminum or steel pushrods? |
|
|
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 _________________ www.type-emotorsports.com |
|
Back to top |
|
|
oprn Samba Member
Joined: November 13, 2016 Posts: 12730 Location: Western Canada
|
Posted: Mon Jan 23, 2023 12:58 pm Post subject: Re: Aluminum or steel pushrods? |
|
|
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. _________________ 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) |
|
Back to top |
|
|
pmriverrat Samba Member
Joined: October 09, 2021 Posts: 92 Location: West Michigan
|
Posted: Mon Jan 23, 2023 8:42 pm Post subject: Re: Aluminum or steel pushrods? |
|
|
[quote="Brian_e"]
oprn wrote: |
He also has a bigger than stock cam, so he will need to set up the rocker geometry, and most likely cut down the push rods.
Brian |
The lift at the valve stock is .332". The Engle 100 is .420. .088 more lift on the Engle. Anyone care to estimate how much might need to be taken off the pushrod length? |
|
Back to top |
|
|
modok Samba Member
Joined: October 30, 2009 Posts: 26787 Location: Colorado Springs
|
Posted: Mon Jan 23, 2023 8:49 pm Post subject: Re: Aluminum or steel pushrods? |
|
|
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. |
|
Back to top |
|
|
Clatter Samba Member
Joined: September 24, 2003 Posts: 7544 Location: Santa Cruz
|
Posted: Mon Jan 23, 2023 11:58 pm Post subject: Re: Aluminum or steel pushrods? |
|
|
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. _________________ Bus Motor Build
What’s That Noise?!? |
|
Back to top |
|
|
modok Samba Member
Joined: October 30, 2009 Posts: 26787 Location: Colorado Springs
|
Posted: Tue Jan 24, 2023 12:35 am Post subject: Re: Aluminum or steel pushrods? |
|
|
And that's why they call him clatter |
|
Back to top |
|
|
RickS Samba Member
Joined: May 05, 2005 Posts: 430 Location: Speonk, NY
|
Posted: Tue Jan 24, 2023 5:58 am Post subject: Re: Aluminum or steel pushrods? |
|
|
modok wrote: |
And that's why they call him clatter |
That right there is funny! |
|
Back to top |
|
|
|