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I'm interested to see this as well, seems like quite a few people run the double roller set, but I haven't heard hardly any discussions about people installing it advanced or retarded and what was gained.
 

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Just out of curiousity, might I ask why you put it there? Correct me if I'm wrong, but its adjustable up to +8 or -8 in 2 degree increments, and advancing the cam is supposed to increase hp in the top end (and retarding it makes better bottom end power). So I was just wondering how you decided that point, (I figure its probably either b/c you can't advance it any more b/c you'll get have too little piston-valve clearnace, or b/c that was where it made the most power)? Just curious because I haven't found much info on this, and I also plan on running the double roller.
 

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Your last post doesn't make much sense to me. I understand how it all works, and how to degree a cam, and I do realize there are clearance issues to worry about between the pistons and valves, but this confuses me:

"thats where the cam will makes it power"

how do you know it will make more power at +4 adv rather than +2 adv or +6 adv?
 

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Advancing a cam shifts the powerband LOWER, rather than higher.

I believe all the Stage 3 cam grinds already have +4 ground into them. So they're already four degrees advanced when you install them 'straight up'. I'll have to check to be sure, but I believe our Stage 3 Turbo grind may even be +6.

And yes, it's always wise to degree a cam to make 100% sure it is what it's supposed to be. They can easily be off a degree or two.
 

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Jonathan_Cain said:
if you know you need to degree a cam, then why dont you understand +4 etc? no cam is made perfect. you need to find TDC, where the valves are opening and closing and match it to the cams birth sheet.
I think you're still completely missing my point and question; what I'm saying is that with the double roller setup you have options as to how you want the cam installed (you can install it up to + or - 8 degrees in 2 degree increments, or 'straight up'). So yes, degreeing the cam is part of the installation process, so is putting clay on top of the piston to measure how close the valves are getting to the piston tops, so is bolting on the front cover and reinstalling the balancer, etc. I'm not asking anything about how to install a cam, degree a cam, etc; I'm saying you had multiple choices when you installed your cam and you could of installed it "straight up", 2 degrees retarded, 2 degrees advanced, 4 ret, 4 adv, 6 ret, 6 adv, 8 ret, 8 adv; and out of all those options you chose 4 advanced-and I was simply asking why.

Yes, I understand you had to degree the cam and measure you piston-valve clearances, anyone playing with cam timing should do both to avoid destroying the engine, but that does not dictate why you would pick +4, over say +8, or -6, or even straight up.

"Mr. INTENSE Advancing a cam shifts the powerband LOWER, rather than higher." This was more along the lines of what I was looking for.

"Mr. INTENSE I believe all the Stage 3 cam grinds already have +4 ground into them. So they're already four degrees advanced when you install them 'straight up'." And this is also very interesting, something I never knew.


So does anyone know (maybe Mr. INTENSE?) which timing setup (0,-x or +x) works best with the S3 blower cam? (kinda reiterating seen96's question)
 

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"I thought that it didnt matter because of the cam/crank sensors."

Are you asking if cam timing matters b/c of the sensors? It would make a difference because you're still physically changing the relationship of time that the pistons are moving up and down to the time that the valves are opening and closing.


"i advanced the cam to broaden my powerband in the lower RPM range. because we all know turbos do the rest themselves "up top" "

Ok, you still missed the question again, I now understand why you advanced it, but why did you only go +4 instead of +6 or +8?
 

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OK, just to keep it in the same post, question to Mr. INTENSE- I am about to put my engine back together, with the S3 cam. However, it will be mostly street driven, so valve seat life is important and I am using LS1 springs and LS1 retainers. So far so good, I got the clearance on both the spring and seal side. I also want to keep (for speed density's sake) the RPMS around 5500RPM, so will I benefit from advancing the cam another +2 degrees, for a total of +6? Or should I leave it at +4?
 

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I've got a question for you, Miko.

First I didn't think the LS1 springs were suitable for such a high lift cam, I thought it was pretty much necessary to run either the full on 130 # springs or the double 135#s?

Secondly, if you're planning on keeping the rpm under 5500 or so, doesn't it seem like that cam is too big considering its supposed to make good power up to about 7000?

Maybe its different w/ you having the bigger supercharger, I'm just confused.
 

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bumpin96monte! said:
So does anyone know (maybe Mr. INTENSE?) which timing setup (0,-x or +x) works best with the S3 blower cam? (kinda reiterating seen96's question)
All of our Blower cam grinds work just fine when advanced four degrees. But you've got to remember that all four profiles are already ground four degrees advanced, so installing one of them 'straight up' will give you the net result of dialing in four four degrees of advance.

Now this is all fine for MOST installations, but there are two exceptions to the above paragraph:

1. Advancing a cam shifts the powerband lower, and retarding a cam shifts the powerband higher. So you can use this information to tweak your powerband to better fit your particular goals.

2. It's always wise to degree a cam to make 100% sure it is what it's supposed to be. They can easily be off a degree or two.

Jonathan_Cain said:
i advanced the cam to broaden my powerband in the lower RPM range. because we all know turbos do the rest themselves "up top"
This makes good sense, and is exactly why our Turbo cam grinds are all ground six degrees advanced.

Miko K said:
I am about to put my engine back together, with the S3 cam. However, it will be mostly street driven, so valve seat life is important and I am using LS1 springs and LS1 retainers. So far so good, I got the clearance on both the spring and seal side.
We strongly recommend that you run considerably stronger valvesprings with that cam. Otherwise, you're just asking for trouble.

Miko K said:
I also want to keep (for speed density's sake) the RPMS around 5500RPM, so will I benefit from advancing the cam another +2 degrees, for a total of +6? Or should I leave it at +4?
Yes, you would definitely benefit from more advance if you only plan to rev to 5,500 RPM - probably on the order of four additional degrees. A dyno is really the only way to know for sure how much cam advance is best though.
 

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Here is a good one. S3 cam at +6 degrees, Diamond pistons, SI valves, 1.7:1 rockers, 105# springs, LS1 retainers. At first it sounded like the valves were smacking the head a little harder, but I guess that was the sound of the valves hitting the pistons, so one eventually broke at around 3000RPMs. I only ran the car for about 15min and went to self destruct mode. I guess I found a limit to advancing...Back to stock rockers and straight-up cam :(

 
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