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1.9s, springs or no?

Sabrewings

Sabrewings

New member
Are 105s really required for 1.9s? I'm not going to be going over 6000RPMs, so if I can at least get that high with no valve float it will do. I know the consensus is better safe than sorry, but has anyone run 1.9s on the stock springs for any length of time?

While we don't know the exact ratio, the ER rockers are somewhere between 1.8 and 1.9 depending on intake or exhaust. ZZP says you shouldn't need springs as long as you're not shifting over 6000. Though I know Whizbang recommends springs just to be sure you don't have valve float.
 


I would say it would be a good idea, but not absolutely necessary. Even with the VS cam, ZZP says you can run stock springs if you want.

Then again, you don't have to go with 105s if you do want to upgrade. SC Drew has been pushing the L76/L92 spring option. 90 lb seat pressure with a 345 lb/in spring rate (same as stock), and can be had very cheap.
 
i am on stock springs with my 1.9s and they are fine. no valve float here. i wouldnt waste the money if youre not going to be shifting over 6000.
 
I think this is a grey area.....

you dont have too, but you can if you want.

I had 1.9's on my 97.... ran fine without. But I put them on anyway.......
 
It's not the money, necessarily. And I've got the heads off so it'd be easy. I just don't really want to put much more stress on my timing chain if I don't have to. 72k miles and I don't feel like cracking open the front cover.

Scimmia, how would those L76/L92 springs run price wise? Also, do they put any significant increase in stress on the timing chain? Where would I look for them?
 
GM part number 12589774, should be around $45 at the local dealer, or less online if you can find somewhere that doesn't kill you on shipping.

With 1.9 rockers on a stock cam, you're going to end up right around .50" valve lift. At that, the stock springs will be at ~248 lb, L76/L92 springs will be ~264 lb, and Comp 105s will be ~262 lb. The LS6 spings that everyone worries about will be at ~277 lb. In short, yes, they would put about the same amount of stress on the chain as the 105s, but less than the LS6 springs and you don't have the breakage issues that the 105s do.

The down side is that the max lift on them is fairly low, .520 in the 2009 catalog (it said .530 in 2008), so they would be limited to rockers or small cams, the XP or any of the Intense cams would be out.
 


So they're still putting increased stress. But, no breakage. Is the increased stress really that critical? I guess down the road I could pop open the cover to change out the chain to a new one and change the dampener. I just don't trust any of the aftermarket setups. And a cam is not in my future as far as I care.

Thanks for the part number, by the way. $34.65 from GMPD including shipping. I'm going to contact my parts guy and see what he can get them for. Usually 10-15% less than GMPD.

Do I still need the valve spring retainers and such just like if I was using 105# or the 90# springs?
 
Sabrewings said:
Is the increased stress really that critical?
Click to expand...

Now THAT is a loaded question; I don't think there's a definitive answer to that one.

Yes, you would definitely want LS style retainers with either the Comp 105s or the L76 springs. Using the stock L67 retainers would give you very high seat pressure, and you would be way over max lift in the case of the L76 springs.

I forgot to add something, SC Drew knows his stuff and he's been talking about these for a while, but I don't know of anyone actually running them for sure. All of the dimensions are the same as the LS6 springs, so I'm sure they'll be fine, though. One of the Regal guys just picked up a set and is waiting for a pair of heads to show up to install them, so it won't be long.
 
yor stock chain would be fine, just dont go up to 130# springs....

you will be fine with upgrading now while the heads are off...

105's and under would be fine on yur stock chain.
 
That's fine. I was planning on ordering the retainers anyway, so nothing changes. I just save $100 on the price of the springs. :)

You, sir, really helped me out here. :th_thumb-up:

Edit: And thank you UR LOSN. I will probably replace it eventually anyway as a preventative maintenance sort of thing to change out the worn dampener. But, not immediately.
 
Sabrewings said:
Thanks for the part number, by the way. $34.65 from GMPD including shipping. I'm going to contact my parts guy and see what he can get them for. Usually 10-15% less than GMPD.
Click to expand...

GMPD has them in sets of 5, the price you gave would be for 10 (atleast that's how it's coming up for me). You would need to buy 15, which be $45.50.
 


Doh, what was I thinking. Of course I'd need 12...

Thanks again. I would've figured it out eventually that I didn't have enough. :th_laugh-lol2:
 


FWIW I have also used 1.9's on stock springs. Shifted at 6400 RPM's. No problems and used them for about 8 months. Stock springs had around 105000 miles on them.
 
Well, I want to put new springs on as long as the heads are off. Perfect time to do it.

Thanks for the info though. I'm sure it'll help someone's decision. :)
 
And that's the only reason I didn't because the heads were not comming off.
 
I have some extra valve keeps laying around if you want some, unless u are just replacing them all. I lost a keeper and had to wait 2 days to get the new ones. I had the heads on the car tho. Pm me if u want a few sent out. (No charge)
 
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