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Discussion Starter · #1 ·
Hello, I have a 05 GTO with a d1 procharger, longtubes, e85, etc. and 88k miles. I just finished college and got a entry level job for now so I figured it's time to change the cam now since I need to replace the water pump anyway and I now own hptuners, so I can tune it myself. From what I looked up, hardened pushrods are not needed and as of now I'm only planning on upgrading the valve springs and changing gaskets of course. I don't think I need a new crank bolt since I'm using the procharger bolt but I'll have to check to see if it is a tty bolt.
I'm undecided on what cam to get. I really like the sc1 cam but I am also interested in the Cleetus Mcfarland bald eagle boost cam listed here: Link
As far as goals, I'm not trying to put down a huge dyno number, I care more about reliability than anything. I don't daily drive my GTO but I want to be able to if needed, so to speak.

Also, I have been looking up install guides and what not, and I see one tip about pressurizing the cylinders when changing the valve springs with a compressor. Now I have the tools to do all that, but what if I changed the valve springs first before doing anything else and before changing them I pull the fuel pump fuse and crank the starter to pressurize the cylinders, that way I don't need to remove the spark plugs, and I can keep cranking the starter every time I do a cylinder to maintain pressure? Kind of like doing a compression test but with the valve covers already off and while all the valve springs are still attached or mixed with new ones of course.

Any suggestions?
Thanks.
 

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guess it would work if you took the rocker off. not something id do to pressurize the cylinder

You should also measure for pushrods. Why skip a step on a procharged motor
 

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At a very minimum, you need to get a pushrod checker to verify the correct length after the cam is installed. Assuming your stock pushrods will work could be a pricey mistake.

Also, if you care more about reliability, then just add a pound of boost if you want more power and leave the stock (reliable) valve train alone.
 

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Discussion Starter · #4 ·
guess it would work if you took the rocker off. not something id do to pressurize the cylinder

You should also measure for pushrods. Why skip a step on a procharged motor
At a very minimum, you need to get a pushrod checker to verify the correct length after the cam is installed. Assuming your stock pushrods will work could be a pricey mistake.

Also, if you care more about reliability, then just add a pound of boost if you want more power and leave the stock (reliable) valve train alone.
I could be wrong but I heard if the base circle of the cam is the same as stock then the length of the pushrods won't change. I don't know what the base circle of the cams I listed is or if it is the same as stock but I would definitely look into it before jumping the gun.

As far as the reliability/power aspect of it goes, one of the biggest reasons for me getting a cam and I feel silly saying it because I don't want to be classified as "one of those guys" is the sound. I love the sound of a cammed ls. Nothing too over the top because I feel like it would get annoying/too obnoxious in traffic at times and I don't want to lose too much drivability. I do like the idea of more low to mid range power if a cam can offer that vs adding boost which will affect the top/overall range more with a procharger.

Here is a video of a procharged gto with a sc1 cam. Link
The sc1 cam has low lift so it is easier on valvetrain vs others.

Texas speed also sells a low lift cam, stage 4 is 222/228 duration which is the same as the sc1 cam, with .550/.550 lift which is less than the sc1. Link

Last time my car was on the dyno, it made 540whp. But I have went from a 4.25 pulley to a 4.00 pulley since then and I then retuned it myself after learning my tuner failed to give me a SD tune which I requested, I haven't dialed in the spark advance as well as I probably could since I'm using e85 as I don't have easy access to a dyno to do trial and error with. In other words, I'm not sure exactly how much power I'm making right now or about how much I will make.
 

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Canadian Corvette and Performance Jam Cam.

Just put air in the cylinder with a compressor. Super easy, just turn it over to get the load on each rocker first and ensure the valves are closed.
 

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Discussion Starter · #6 ·
Canadian Corvette and Performance Jam Cam.

Just put air in the cylinder with a compressor. Super easy, just turn it over to get the load on each rocker first and ensure the valves are closed.
That looks like an awesome cam for a procharger and sounds great, but I feel like it might be too big of a cam for my purposes. I'll definitely consider it though, I would think a cam of this size would hurt low end power but it seems to be advertised differently but I can't find much proof.
"230/242 .608"/.615" 115+4"
 

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That looks like an awesome cam for a procharger and sounds great, but I feel like it might be too big of a cam for my purposes. I'll definitely consider it though, I would think a cam of this size would hurt low end power but it seems to be advertised differently but I can't find much proof.
"230/242 .608"/.615" 115+4"
Not sure what too much of a cam means. Has a blower on it, so low end torque cant be lost even if the cam would effect that. If anything it would come in sooner, which is why the lsa is looser and advanced.
 

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Chromolly pushrods are cheap as fuck and worth it no matter what you are doing to it. Comp cams pushrod length checker is 25 bucks and pushrods are 100 bucks. Shit I'm pretty sure tsp sends you there pushrods in their cam kit. Just make sure they are the right length.
 

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I'm confused. Why would anyone think its a good idea to pressurize the cylinder to remove the valve springs? Thats a waste of time, and pointless. what happens if you break the seal loose and knock the valve down? oops? Then your compressor is running the whole time because its not perfectly sealed.......just a bad idea to me. I've done more cam swaps than i care to think about. Lets grap some common sense up out the air real quick and think about this for a minute.....sorry for the sarcasm but i hate poor internet info and suggestions especially when it can put an inexperienced person in a bind.....so....if you simply bring the piston up to top dead center on the cylinder that you are working on, the valves can only drop a 1/4". No chance of them dropping in the guide. No air to fool with. No compressor running. No constant hiss from the rings leaking the pressure. pull spark plugs out, use a small screwdriver or long allen wrench and stick it in the spark plug hole, while the fans are out and the front of the motor is apart (before removing the balancer) use a wrench to turn engine over and feel for the piston moving up. You can feel when it gets to the top. DO NOT USE THE STARTER!

If you do not have the $$$ to do this correctly with hardened pushrods, DO NOT DO IT AT ALL. Just wait. Stock pushrods bend all the time with a stock cam....why would you think they are good enough on stronger springs?? I dont care what you read on the internet, DO NOT SKIP hardened pushrods. Skip the whole project if you cant do it correctly....at least your car is running right now....skip getting the proper parts....it wont be running long.
 

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Discussion Starter · #10 ·
Not sure what too much of a cam means. Has a blower on it, so low end torque cant be lost even if the cam would effect that. If anything it would come in sooner, which is why the lsa is looser and advanced.
Well, I'm no expert on camshafts so forgive me if any of my assumptions seem wrong. I say it's a big cam because the duration and lift are pretty large compared to low lift camshafts and the stock camshaft, more lift and longer duration I believe will be harder on the valvetrain and affect reliability.
Prochargers make most of their power at the top of the rpm range and the least at the bottom because that where they make the least amount of boost, So I assume having a large camshaft that would normally hurt low end torque will still do so at least somewhat with a procharger, might not be as dramatic compared to if you were n/a.
 

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Discussion Starter · #11 ·
Chromolly pushrods are cheap as fuck and worth it no matter what you are doing to it. Comp cams pushrod length checker is 25 bucks and pushrods are 100 bucks. Shit I'm pretty sure tsp sends you there pushrods in their cam kit. Just make sure they are the right length.
I'll go ahead and get the pushrods and checker, it sounds like I might be needing different length pushrods anyway.
 

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Discussion Starter · #12 ·
I'm confused. Why would anyone think its a good idea to pressurize the cylinder to remove the valve springs? Thats a waste of time, and pointless. what happens if you break the seal loose and knock the valve down? oops? Then your compressor is running the whole time because its not perfectly sealed.......just a bad idea to me. I've done more cam swaps than i care to think about. Lets grap some common sense up out the air real quick and think about this for a minute.....sorry for the sarcasm but i hate poor internet info and suggestions especially when it can put an inexperienced person in a bind.....so....if you simply bring the piston up to top dead center on the cylinder that you are working on, the valves can only drop a 1/4". No chance of them dropping in the guide. No air to fool with. No compressor running. No constant hiss from the rings leaking the pressure. pull spark plugs out, use a small screwdriver or long allen wrench and stick it in the spark plug hole, while the fans are out and the front of the motor is apart (before removing the balancer) use a wrench to turn engine over and feel for the piston moving up. You can feel when it gets to the top. DO NOT USE THE STARTER!

If you do not have the $$$ to do this correctly with hardened pushrods, DO NOT DO IT AT ALL. Just wait. Stock pushrods bend all the time with a stock cam....why would you think they are good enough on stronger springs?? I dont care what you read on the internet, DO NOT SKIP hardened pushrods. Skip the whole project if you cant do it correctly....at least your car is running right now....skip getting the proper parts....it wont be running long.
I don't mind the sarcasm, I'd rather do it the right way. I'll get the pushrods but if I end up getting a larger cam like the jam cam "230/242 .608"/.615" 115+4" should I consider upgrading any more of my valvetrain?
 

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I don't mind the sarcasm, I'd rather do it the right way. I'll get the pushrods but if I end up getting a larger cam like the jam cam "230/242 .608"/.615" 115+4" should I consider upgrading any more of my valvetrain?
Trunion upgrade and pushrods. You will have a bullet proof top end.
 

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Well, I'm no expert on camshafts so forgive me if any of my assumptions seem wrong. I say it's a big cam because the duration and lift are pretty large compared to low lift camshafts and the stock camshaft, more lift and longer duration I believe will be harder on the valvetrain and affect reliability.
Prochargers make most of their power at the top of the rpm range and the least at the bottom because that where they make the least amount of boost, So I assume having a large camshaft that would normally hurt low end torque will still do so at least somewhat with a procharger, might not be as dramatic compared to if you were n/a.
Its an average cam. Even small cams can be hard on the valve train, lots of them are worse as they have very aggressive lobes.
A procharger is gonna make power all the time over its parasitic loss. Which in most cases 2.5k and up, bov's are a large factor as well as the volume and velocity of the motor itself and how it reacts. Mine for instance makes 500lbs at 3k, which would never happen no matter what cam is used n/a. Just isnt possible on a 5.7. And I ran a larger cam prior, made more power sooner and held it longer than the small cam I ran before that. Only thing that made a drastic torque change in my mods where the exhaust, then overall linear boost.
 

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I don't mind the sarcasm, I'd rather do it the right way. I'll get the pushrods but if I end up getting a larger cam like the jam cam "230/242 .608"/.615" 115+4" should I consider upgrading any more of my valvetrain?
CHE (search it) trunion upgrade.

If you want a nice boost in power but want to retain really nice driving manners, look into the summit ghost cam (222/233 115 lobe sep) its a really good choice. An N/A ls1 with ported heads and a fast intake made 455rwhp with a stalled auto.
 

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I have run a procharger with a cam that has identical specs to the jam cam you reference for 10 years. It was custom specced by Ed Curtis at FTI and it drives real well, no bucking or excessive reversion. With superchargers and nitrous it is good to have some exhaust lift/duration to get the exhaust gasses out and lower dynamic compression ratio a bit in some cases. Good pushrods and upgraded springs are important to prevent valve float. Agree with the other guy in finding TDC vs. the air compressor method. Having done both, the TDC method is much easier and fool proof.
 

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Discussion Starter · #18 · (Edited)
Thanks for the info guys. I'm currently planning on going with the Jam Cam. I'm about to start ordering all the things I'll need for sure. I guess I'm better off waiting to order the pushrods later after I measure, maybe I'll get some 7.4 pushrods off amazon with a free return policy in case it doesn't work out, possibly lower downtime.

Should I consider changing the timing chain or oil pump while I'm in there at 88k miles? I found a Melling m295 oil pump for $60.


Are all the bolts reusable? I know the stock crank bolt should be but I have a Procharger bolt.
Does anyone know of a very descriptive install guide, preferably for an ls2, not that an ls1 would be much different.
I found this which looks pretty good but I'm open to look at more: Link

So far my shopping list is as follows,


Jam cam
CHE Trunion kit
BTR platinum ls dual spring kit with titanium retainers Link
FEL-PRO valve cover gasket set
FEL-PRO timing cover set
push rod checking tool
valve spring compressor
ls lifter tool
Edit: forgot to add br7ef spark plugs, only have a few hundred miles on my tr6s, but Might as well when I have them out.
Which comes out to about $1,100, am I missing anything, or do I need something else? I've installed a Procharger, so obviously I have all the tools for that part of the job.
 

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I wouldn't touch the oil pump or timing chain as the LS2 chain is pretty stout. I would not reuse the stock crank bolt, its TTY and the threads usually have some tweak to them when it comes out. For the procharger I would toss the little black bypass valve if that's what you have. They leak and don't flow enough resulting in both lost HP and compressor surge. The stock procharger intercooler is good for about 10psi, anything ore than that it doesn't cool very well. Last, anywhere you can reduce bends or get larger pipe in there do it. The stock piping configuration is super restrictive with all the bends and reductions to 2.5" pipe.
 

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Discussion Starter · #20 ·
I wouldn't touch the oil pump or timing chain as the LS2 chain is pretty stout. I would not reuse the stock crank bolt, its TTY and the threads usually have some tweak to them when it comes out. For the procharger I would toss the little black bypass valve if that's what you have. They leak and don't flow enough resulting in both lost HP and compressor surge. The stock procharger intercooler is good for about 10psi, anything ore than that it doesn't cool very well. Last, anywhere you can reduce bends or get larger pipe in there do it. The stock piping configuration is super restrictive with all the bends and reductions to 2.5" pipe.
Thanks, I have the longer procharger crank bolt which I think is reusable, I'll call Bob at brutespeed later to confirm.
What are my chances of the 7.4 pushrods fitting? I think I could save some $ if I get a full kit.
As for the procharger piping, my build was a budget build, I didn't have a job at the time and I got most of my procharger related items off of craiglist. Most of the piping I had to source myself. I bought a ton of silicone couplings and Frankensteined it together as best I could. I used 3 inch tubing in every spot I could but unfortunately, I probably have more bends than the normal procharger setup. I'm not proud of it but I chose to temporarily cut costs there instead of the fuel system or the clutch upgrade.
One thing that I've always wanted to try but I'm afraid of the ICT's, is rotate the outlet on the headunit to be pointed more up and to the left and then attach it directly to the throttle body, bypassing the intercooler all together. In the future, I wanted to get one of those intake manifold water coolers to make this setup safer and doable but they are too costly at the moment for me.

I have the 04 hood thanks to the previous owner(no hood scoops) and before I did the hardcore procharger Intake mod, My engine bay would get heatsoaked and I would never see iat's below 150 unless I was on the highway with no traffic for long periods which is rare in houston.
I'm running e85, so I wonder just how doable bypassing the intercooler is or if it is doable to stick a tiny water cooler between the procharger and manifold if I try this more direct setup. Thoughts?
 
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