BillSS

I'm about to order a cam for my car. I'm leaning towards the TR 224/224 114 LSA. This car is a daily driver and must pass emissions. Now I am planning on buying the cam and the springs.

But for another $200 I can get titanium retainers as well as hardened pushrods. I see the value of the retainers but don't see why I would want the pushrods.

From what I understand if I mis-shifted my car (which I have done in the past and bent my pushrods) and I have hardened pushrods, wouldn't they break something else in the car by not bending??

Can you tell me why I would want to spend the extra money on the pushrods?

Thanks in advance.

9T9BlueTA

iTrader: (2)

I ran that cam with stock pushrods with no problems what so ever.

BillSS

Cool. Did you go with titanium retainers?

2xLS1

iTrader: (25)

For the bee hive style spring such as a comp 918, there is only 2 grams difference in weight between a Ti retainer and stock because the retainer is so small. 9 grams vs 11 grams. I'm not suggesting not to get them. Just throwing out some info. I found no difference in weight between stock push rods and Thunder Racing Ch/Mol push rods. Their advantage would be in less deflection at higher rpms with stiffer springs. All parts were weighed on a tripple beam scale.

9T9BlueTA

iTrader: (2)

I always go with the Ti retainers. Its good insurance if you are going to rev higher than stock.

Fulton 1

iTrader: (9)

The OEM pushrods are notorious for flexing (not a good valvetrain characteristic). I would get the hardened pushrods.

1Bad RamAir

Since your in there I would go hardened pushrods. If you do any racing it will be worth it. As for the mis shifts get a B&M Ripper or other shifter, problem solved. Just my .02

BillSS

Well, I'm hoping not to miss any more shifts since I cut some length off my B&M but you never know what may happen!

So what WOULD happen if I had hardened pushrods and misshifted down a gear at redline??

samz28

what do you want to bend? the piston/valve contact or the pushrod?

NiceTry

iTrader: (1)

No one is PERFECT there will always be the chance that you will miss a shift, and i have broken stock pushrods and they tore into the head. stock pushrods is kinda like saying well why should i buy good tires? If i loose control and they hold up i might slide further and hurt my car.

BillSS

Damn. In this thread and others on similar topics it always seems to be a 50/50 split on going with hardened or stock pushrods!

Fulton 1

iTrader: (9)

Oh no, not this debate again . The pushrod was never designed to be a fusible link in the valvetrain. Several years ago we even had a member (might have been in the old LS1.com days) that was an engineer from Jesel (don't recall his ID) and he was adamantly opposed to the notion that the LS1 pushrods were designed to break in the event of a mechanical over-rev. The job of the pushrod is to accurately transmit the motion of the cam lobe (via the rocker arm) to the valve. If its flexing under load, then its simply not doing its job.

Look at it this way, you CAN mechanically over-rev any engine - pushrod, OHC, rotary, or otherwise - and cause damage. There is nothing unique or special about the LS1 pushrods making them fusible.

This is like saying that you broke your ring gear on a missed shift so therefore everybody should continue using the weak 10-bolt rearends. Just a silly, backwards argument IMO - especially when you're considered an aggressive cam with heavier valvesprings...

BillSS

Good point but I guess my predicament is that is my 224 cam really that aggressive?
Enough to justify hardened pushrods and retainers??

Assuming that money plays a bit of a factor here is it worth the extra dollars considering this specific cam?

TheMongoose

i'd say btwn cam and stiffer springs that's enough to flex the stock ones at high rpm. i decided to go hardened after hearing both sides of this discussion

SidewayzOZ

iTrader: (11)

With stock cam and valvetrain, I would say yes stick with stock pushrods...but going with a bigger cam go with the hardened ones. You dont want to have a planned weak link in your car. IMO it would defeat the whole point of getting a stronger valvetrain. The extra strength of the valvetrain would never be used if your pushrods cant even handle it.

nuzee

iTrader: (2)

Valve train stability is what everyone should be after. Lighter parts and parts that flex less provide more stability.

BTW, the term "hardened pushrod" used to mean nothing more than a pushrod that was surface hardened to allow it to rub and not wear against pushrod guide plates. I now see the term being thrown around as something stiffer or stronger. Misconception?? or am I missing something??

LS1x2

iTrader: (11)

I run stock pushrods in my motor. Sees 7k all the time and has seen 7500 a few times. I've checked them. They are fine If it ain't broke, I'm not gonna fix it. They seem to be strong enough for there to be no need for the hardened ones.

Fulton 1

iTrader: (9)

As long as the metal wasn't plastically deformed during flexure you will see no evidence after the fact. So, just because they "look" fine doesn't really mean anything other than that they haven't yielded or broken.

whitecamaross

look, i just put the same cam you want except mine is on a 112 lsa. i got the hardened pushrods and comp cam springs with titatnium retainers and let me tell you that the insurance you have with all these items is awesome. i had two bent pushrods without me even knowing and since you are already there why put the same stock items on again? i suggest you get everything in one shot and get it done right. i did the cam myself and it is very easy if you have tools. the car will be noisier, but thats just how it is. you will love the cam you are gonna get and i am on stock tuning on my 99 camaro ss. do the job right one time so you have to go back again and replace springs and pushrods later on. get the whole package and be confident that your internals will be ok.

JohnR

iTrader: (1)

We need some Mechanical Engineers to jump in on this pushrod flex issue. Here's my .02.
What is being discussed is a material property called "Modulus of Elasticity". Most steels all have nearly the same value. (Brass and Aluminum are different materials and have radically different Modulus'). Heat treating the steel makes it stronger, but it can't change the "Modulus". Stronger doesn't me the ability to resist deflection, it means the ability to absorb stress and not "Yield" or break. If the two different style pushrods have the same circular dimensions, that is, the same OD and same ID then the flex under the same load will be identical between the stock and the hardened pushrod. The difference is that the hardened pushrod has a higher "Yield" strength which allows it to take more stress than the stock pushrod and still return to it's original unloaded state. It will still flex, it just won't stay that way as easily. The only way to reduce the flex is to increase the pushrod's material cross-section. This is most easily done by increasing the rod's outside diameter; like from 5/16 to 3/8.
The same thing happens on stud mounted rockers. Going from a heat-treated 3/8 stud to a heat-treated 7/16 stud reduces rocker deflection because the stud's cross sectional area has increased by 36%. The heat-treatment just keeps them from staying bent or breaking so easily.

Now that was a mouthful!
How about some of you ME student/graduates jumping in here and tell me I'm full of it?

John