Comp 901 springs with factory 318 retainers, (with pics)

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prorac1

prorac1

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Since I have had some questions as to what the final clearances are when using comp 901 springs (or equivalent) with factory retainers, I pulled the calipers out when the springs came in the mail. This way, right, wrong, or otherwise, there will be digital facts on FABO. Here's what we found.

The outside diameter of the spring measured as the manufacturer states. 1.494.

The inside diameter also measured as the manufacturer stated. 1.080. So no surprises here.

IMG_3427.JPG



Here is a picture of the retainer on the valve spring. It dosent quite reach the outside edge, but it's definitely well supported.

IMG_3423.JPG


Here's the valve spring without the retainer. It's a thick wire as others have stated.
IMG_3424.JPG


Here's a pic of the retainer measurement. It was actually much smaller OD than I anticipated at 1.336.



IMG_3429.JPG


And here's the measurement of the ID of the retainer spring seat area. It measured out to 1.004. A difference between the retainer ID and the spring ID of .076.


IMG_3428.JPG



So there's the numbers.

I'm going to sleep on it. Lol.

Hope this helps somebody.

Eric
 
prorac1 said:
I never doubted you Rob.

Ok…maybe a little. Lol.

But now we have numbers, and my inner geek likes that. Lol.

Thanks again for all the help on this.

Eric
Click to expand...

I have used the 901s more than once with stock retainers I just never recorded measurements. lol
 
I think others have run them for years like that, no issues. It's good to double check.... :)
 
I was surprised the factory retainer was that small OD. I was expecting 1.38-1.39. But it seems to fit decent ID to ID, so we're good.
 
Hopefully we will be setting up the heads and degreeing the cam in the next couple weeks!

Cam card.


IMG_3426.JPG
 
Good numbers! I was looking for this info a while back.

Quick question- When the retainer is pushed all the way to one side, how much of the spring wire is exposed up top (visually)?

img_3423-jpg.jpg
 
The problem I had with the 901's and stock retainers, is the stock retainers would let the spring make contact with the stock rocker arms. Seemed a little sloppy to me. I used the Comp retainers instead.
 
1969reddart said:
The problem I had with the 901's and stock retainers, is the stock retainers would let the spring make contact with the stock rocker arms. Seemed a little sloppy to me. I used the Comp retainers instead.
Click to expand...

How much contact? Was it possible to "clerance" the arm?

I'm assuming these were stock stamped steel hydraulic rockers?

Thanks for the input. We will keep an eye out for that.
 
IMG_3435.JPG
IMG_3436.JPG

This is the retainer slid all the way to each side. It moves about .030 each way.

If we had more spring pressure I'd be worried. But for these little springs I think it will hold up fine.

Hope this helps. Eric

mopowers said:
Good numbers! I was looking for this info a while back.

Quick question- When the retainer is pushed all the way to one side, how much of the spring wire is exposed up top (visually)?

View attachment 1715126709
Click to expand...
 
prorac1 said:
How much contact? Was it possible to "clerance" the arm? I'm assuming these were stock stamped steel hydraulic rockers?
Click to expand...
I am not sure I would do that. The metal is not all THAT thick to start, and they have been known to break.
 
Once it's all assembled I will run the valve train through its cycle and check for clerance.

Aftermarket retainers must be flatter I'm assuming?
 
We're going to measure everything upon head assembly for max movement/worst case scenario.

I'll report back.

But probably……


IMG_3439.JPG
 
Elgin hydraulic that Rob, (Rustyratrod) told us about and had ran before.

Should have the thump we're looking for while still having decent bottom end.

Kit came with cam, lifters, and springs for $184.

And, thanks again Rob.

Eric L




IMG_3404.PNG
 
Let us know how that works. I would like to hear that one run.
prorac1 said:
Elgin hydraulic that Rob, (Rustyratrod) told us about and had ran before.

Should have the thump we're looking for while still having decent bottom end.

Kit came with cam, lifters, and springs for $184.

And, thanks again Rob.

Eric L




View attachment 1715126789
Click to expand...
 
toolmanmike said:
Let us know how that works. I would like to hear that one run.
Click to expand...

We found a couple YouTube videos of it. But not a lot. But I will tell you this.

It had some shag nasty thump.


So we're hoping to turn the jelly bean 318 into Icky Thump.

We will defiantly have videos eventually……if I don't mess up the install and flatten every lobe on it. Lol
 
prorac1 said:
We found a couple YouTube videos of it. But not a lot. But I will tell you this.

It had some shag nasty thump.


So we're hoping to turn the jelly bean 318 into Icky Thump.

We will defiantly have videos eventually……if I don't mess up the install and flatten every lobe on it. Lol
Click to expand...
Any cam with close to 300° is going to be a thumper. I'm surprised the @.050 is so mild. The 112° c/l will help with that.
 
toolmanmike said:
Any cam with close to 300° is going to be a thumper. I'm surprised the @.050 is so mild. The 112° c/l will help with that.
Click to expand...

The intake centerline is a 108. Lobe seperation is 112.

The cam in my LSX is less than 10 degrees bigger in duration. Lol

This thing is going to THUMP. Lol
 
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