Crane 1.8 gold rockers on LS6 - Stock Springs ok?
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Crane 1.8 gold rockers on LS6 - Stock Springs ok?
Hey Folks,
Need some guidance from the experts. I was wondering if the stock ls6 springs were sufficient for Crane 1.8 quick lift rockers. This is on a Cadillac CTS-V, so please no comments on I should have gone for cam. If concensus is springs, would 918's do, or is dual spring required? What dual spring kit will fit stock heads without machining and work well? Any guess as to real world gains with 1.8's (other mods headers, intake,exhaust )
Thanks
Need some guidance from the experts. I was wondering if the stock ls6 springs were sufficient for Crane 1.8 quick lift rockers. This is on a Cadillac CTS-V, so please no comments on I should have gone for cam. If concensus is springs, would 918's do, or is dual spring required? What dual spring kit will fit stock heads without machining and work well? Any guess as to real world gains with 1.8's (other mods headers, intake,exhaust )
Thanks
#2
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ok do this, its an equation for finding your new lift by increasing the rocker ratio
as an example we will use my cam since I dont know your specs
228R 228/228 .588/.588 112lsa stock 1.7 rocker
so what we are gonna do is take 588(intake and exhaust lift) and devide it by 1.7
588/1.7 = 345.8823529411764058823529411765
now we take that number and multiply it by your new rocker ratio to get your lift
345.8823529411764058823529411765 x 1.8 = 622
so by using a stock 1.7 rocker im at 588 lift and using a 1.8 rocker im up to 622
understand?
as an example we will use my cam since I dont know your specs
228R 228/228 .588/.588 112lsa stock 1.7 rocker
so what we are gonna do is take 588(intake and exhaust lift) and devide it by 1.7
588/1.7 = 345.8823529411764058823529411765
now we take that number and multiply it by your new rocker ratio to get your lift
345.8823529411764058823529411765 x 1.8 = 622
so by using a stock 1.7 rocker im at 588 lift and using a 1.8 rocker im up to 622
understand?
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Stock Cam specs are:
204/218 int/exh @ 0.05" duration
0.551" / 0.547" int/exh lift
117 LSA
So that said I would be at total lift of .583. I guess the overall question I have is whether LS6 springs would sufficient to control valve float.
204/218 int/exh @ 0.05" duration
0.551" / 0.547" int/exh lift
117 LSA
So that said I would be at total lift of .583. I guess the overall question I have is whether LS6 springs would sufficient to control valve float.
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The stock springs won't keep up with the acceleration rates of those rockers. I would get the PAC 1218's or better yet the PAC 1518's, which will run a lot longer mileage wise. These rockers come off the seat at a high rate, you will need new springs. I don't trust the Comp 918's only because there still may be a few sets of the bad ones floating around out there and PAC's stuff is excellent (they used to make the Comp 918's).
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The stock springs won't keep up with the acceleration rates of those rockers. I would get the PAC 1218's or better yet the PAC 1518's, which will run a lot longer mileage wise. These rockers come off the seat at a high rate, you will need new springs. I don't trust the Comp 918's only because there still may be a few sets of the bad ones floating around out there and PAC's stuff is excellent (they used to make the Comp 918's).
I know they are made for higher lift, and they are heavier - but won't they last longer and not wear out as quick because with a light lift of .583 max your operational parameters lie well under the max lift that spring is capable of.
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The stock springs won't keep up with the acceleration rates of those rockers. I would get the PAC 1218's or better yet the PAC 1518's, which will run a lot longer mileage wise. These rockers come off the seat at a high rate, you will need new springs. I don't trust the Comp 918's only because there still may be a few sets of the bad ones floating around out there and PAC's stuff is excellent (they used to make the Comp 918's).
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Comp used to have PAC make the 918's for them, then they switched manufacturers and ran into problems. If you go straight to PAC (there are a couple of vendors that sell them) you in effect end up with the original 918. The 1518's have more surface treatment to last longer. Both should be compatible with stock hardware. "Yeahdoug" (I think) is a PAC representative, shoot him a PM with technical questions. Find a vendor that has them.
Here you go, Speed Inc. carries them:
Link
Here you go, Speed Inc. carries them:
Link
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Hey Folks,
Need some guidance from the experts. I was wondering if the stock ls6 springs were sufficient for Crane 1.8 quick lift rockers. This is on a Cadillac CTS-V, so please no comments on I should have gone for cam. If concensus is springs, would 918's do, or is dual spring required? What dual spring kit will fit stock heads without machining and work well? Any guess as to real world gains with 1.8's (other mods headers, intake,exhaust )
Thanks
Need some guidance from the experts. I was wondering if the stock ls6 springs were sufficient for Crane 1.8 quick lift rockers. This is on a Cadillac CTS-V, so please no comments on I should have gone for cam. If concensus is springs, would 918's do, or is dual spring required? What dual spring kit will fit stock heads without machining and work well? Any guess as to real world gains with 1.8's (other mods headers, intake,exhaust )
Thanks
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I am sure I won't be going cam in the future. I do not need any more lope or emmisions concerns. Again this is on a Cadillac CTS V. Will the patriots require any machining to the heads? Any down sides?
#14
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I have just ordered a cam grind to take into account my high lift rockers, i have 1.85 Comp cam rockers, but i have now decided i need more duration. No one seems to think its a problem, so it is possible if you change your mind. I got a 35bhp peak gain out of my rockers, just for the record, but mine is a 383.