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Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

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Old 01-25-2006, 04:06 AM   #11
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With 1.9 reworked stock rockers stock springs are fine as long as shift points are 5800 RPM and lower. This isn't a big deal since until you do some bigger mods shifting at a higher RPM will not help much.

Here is a good article on rockers, springs, retainers, etc.
http://www.zzperformance.com/grand_p...les1.php?id=53
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Old 01-25-2006, 09:25 AM   #12
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1.9 Rockers make power up to 6000. Shifting earlier than this negates the extra power 1.9s can give you as unlike cams they do not broaden the entire powerband only the upper part (higher rpm). You can certainly run stock springs with any ratio rocker if you only turn the motor to 5600-5800 but again your wasting potential.
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Old 01-25-2006, 07:03 PM   #13
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Quote:
Using a modified 1.9 ratio rocker without changing the valve springs works well because the stock springs are light and you donít get much rocker deflection. You do risk valve float this way but most people donít have that problem.
Read the article and found this. So, what springs are the lightest, create the least amout of rocker deflection, but don't risk the falve float?

Then when I have a look at the modified rockers on the website, I see this.



Quote:
Limited production of 1.9 modified rocker arms. Due to customer requests, we ran a few sets of modified rocker arms.



These started out as a stock rocker arms. The seats have been welded in and remachined at a new location to achieve a ratio of 1.9 (vs. the stock 1.6). There are hundreds of this style of rocker arm in the 3800 market, all with excellent results.



These work with all stock or aftermarket pushrods, lifters, springs, retainers. They will not work with aftermarket cams. Aftermarket springs are recommended for shift points over 6100.
So, you guys say 6000rpm needs new springs. ZZP says 6100rpm or lower does not. Why the contradiction?
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Old 01-26-2006, 03:14 AM   #14
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5800RPM is safe... their are other factors that will effect when you get valve float. Some people have been able to run 6000RPM and higher no problem. I don't think that shifting over 6000RPM is worth $180+, a harder install, and a timing chain dampener that is going to wear out faster.
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Old 01-26-2006, 10:42 AM   #15
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Quote:
Originally Posted by fantastic88
So, you guys say 6000rpm needs new springs. ZZP says 6100rpm or lower does not. Why the contradiction?
Not all cars will perform the same. Yes some people have succsesfully ran 1.9'* with stock valve springs. Some people had valve float problems using stock springs. Just a difference of opinions.
I say change out the valve springs, that way you won't have any doubt.
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Old 01-26-2006, 03:46 PM   #16
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Quote:
Originally Posted by fantastic88
Quote:
Using a modified 1.9 ratio rocker without changing the valve springs works well because the stock springs are light and you donít get much rocker deflection. You do risk valve float this way but most people donít have that problem.
Read the article and found this. So, what springs are the lightest, create the least amout of rocker deflection, but don't risk the falve float?

Then when I have a look at the modified rockers on the website, I see this.



Quote:
Limited production of 1.9 modified rocker arms. Due to customer requests, we ran a few sets of modified rocker arms.



These started out as a stock rocker arms. The seats have been welded in and remachined at a new location to achieve a ratio of 1.9 (vs. the stock 1.6). There are hundreds of this style of rocker arm in the 3800 market, all with excellent results.



These work with all stock or aftermarket pushrods, lifters, springs, retainers. They will not work with aftermarket cams. Aftermarket springs are recommended for shift points over 6100.
So, you guys say 6000rpm needs new springs. ZZP says 6100rpm or lower does not. Why the contradiction?
On our SSEi we have 1.9'* and stock springs. It has been this way since the car had 70k on it (it now has 160k). Shift points are at 5950, limiter at 6200. It doesn't have any valve float, and we've had no problems at all with it really. You could probably run this setup and be just fine, however just to be sure you'll have no float, you can install springs and then if you later want to spin it to 6200 or something like that for whatever reason, you'll be able to. Then if you install a cam in the future you can keep your springs. We never changed out the 90lb. springs in the GTP when we put the XP cam in. It spins to 6600rpm with ease and no signs of float.

We also have stock springs in the Monte Carlo and it has 1.9'* and we haven't had any valve float problems with that car either. All cars are different. When we had 1.9'* in the GTP before we put the springs in it it had valve float like crazy and the car only had ~12k miles on it.

Shawn
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Old 01-26-2006, 05:25 PM   #17
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I noticed your Olds is a 97. Mine is a 97 too, so we should have the same kind of heads on our engines. From what I hear, the 97'* have a slightly different design that doesn't allow the 90lb springs to fit properly.

This is what has held me back from getting 1.9'*.

Some other forums have a lot of info about the 97 heads, just thought youd wanna know.
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Old 01-26-2006, 05:30 PM   #18
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Quote:
Originally Posted by Sol
I noticed your Olds is a 97. Mine is a 97 too, so we should have the same kind of heads on our engines. From what I hear, the 97'* have a slightly different design that doesn't allow the 90lb springs to fit properly.

This is what has held me back from getting 1.9'*.

Some other forums have a lot of info about the 97 heads, just thought youd wanna know.
The LS6 springs wont seat right in the 97 heads however the 105# Compcams will and would allow you to run 1.9'* no problem.
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Old 01-26-2006, 07:32 PM   #19
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Quote:
105# Compcams will and would allow you to run 1.9'* no problem.
So this is the way to go in my 97? Also, my old bolts should be good too. Or, will I need to order new ones?
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Old 01-26-2006, 07:41 PM   #20
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Don't the 105'* take a little power away, as well as put more strain on things?
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