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I am purchasing a low lift voodoo cam for my 2001 Silverado lm4 out of a 2003 trailblazer ext swapped to it cam specs Advertised Duration IN/EX: 269/281; Duration @ .050" IN/EX 219/231; Valve Lift IN/EX: .542"/.542"; LSA/ICL: 113/109; RPM Range: 1500-6000 and gettin 7.4" 5/16 pro series push rods from crane cams and the o.e. replacement hydraulic lifters from crane cams I know they advertise that can be used with all stock internals but I was was wondering if anyone could recommend me to a budget friendly more reliable better fitted valve spring to that cam? And I have been debating on getting 11/32 pushrods is there any modifications I would have to make or would they work just fine with stock rockers and parts listed above?
Don't buy push rods until after you assemble the motor. Changing cams etc. often causes the required push rod length to be different from stock. Since there's no adjustment in the valve train like there was in many earlier motors, the lifter preload must be set by choosing the correct push rod length. They are available in .025" length increments in the range you will need.
For what you're doing, there's no need for 11/32" push rods. A good quality set of 5/16" will do just fine.
As far as the lifter preload you will need to set up for, that depends on WHICH "replacement" lifters Crane is supplying. The usual choice around here is the LS7 ones, which have about .150" of travel, and want about .080" or so of preload. Other "replacement" ones may have less travel and therefore want less preload. Others such as Morel or Johnson are very picky about preload and typically want MUCH less than stock. Find out EXACTLY what your lifters need before buying push rods.
https://www.texas-speed.com/p-6432-p...pac-1211x.aspx Get the 1218 springs and their associated hardware. Remember, there's ALOT more to spring specs and performance than just some "max lift" number. You have a MUCH more aggressive cam than any stock one, so for example stock LS6 springs, even though their "max lift" spec would appear to be OK, are INADEQUATE.
Don't buy push rods until after you assemble the motor. Changing cams etc. often causes the required push rod length to be different from stock. Since there's no adjustment in the valve train like there was in many earlier motors, the lifter preload must be set by choosing the correct push rod length. They are available in .025" length increments in the range you will need.
For what you're doing, there's no need for 11/32" push rods. A good quality set of 5/16" will do just fine.
As far as the lifter preload you will need to set up for, that depends on WHICH "replacement" lifters Crane is supplying. The usual choice around here is the LS7 ones, which have about .150" of travel, and want about .080" or so of preload. Other "replacement" ones may have less travel and therefore want less preload. Others such as Morel or Johnson are very picky about preload and typically want MUCH less than stock. Find out EXACTLY what your lifters need before buying push rods.
https://www.texas-speed.com/p-6432-p...pac-1211x.aspx Get the 1218 springs and their associated hardware. Remember, there's ALOT more to spring specs and performance than just some "max lift" number. You have a MUCH more aggressive cam than any stock one, so for example stock LS6 springs, even though their "max lift" spec would appear to be OK, are INADEQUATE.
Ok i was just hoping I could buy the push rods before hand cause this is daily driver advetises as stock springs and would like to do the cam swap on a weekend but I will wait to get proper measurements ok what lifters do you recomend for under 300 and I am gonna replace just timing chain I see alot of kits with the sprockets and all but trying to keep entire swap under 1000$ and is there anything else I might want to do while doing this so far my parts list is cam pushrods springs lifters timing chain belt gaskets bolts harmonic high flow oil pump
And about the cam i have chosen is it to big I'm looking to push the limit for daily driver cam sizes I am ordering everything tonight or in morning and I'm set on getting a lunati cam.
The Crane lifters are probably just fine; although if you haven't bought them yet, look at these. http://rpmspeed.com/gm-performance-ls7-lifters/ Those guys also have a ported LS6 oil pump sometimes; might have to call and ask. Otherwise use the Melling 10296. They also have timing sets. You don't need anything radical, if your gears are still good you can just replace the chain http://rpmspeed.com/ls1-gm-ls2-timing-chain/.
I think the cam you want seems reasonable, but for a larger motor in a lighter vehicle. Not sure why you want a Lunati cam in particular, not that there's anything wrong with them, just, they may or may not offer "the right" thing for what you're doing. IMO you'd do better with a smaller one that that in your application, unless you have ALOT of converter and/or gear. The most likely candidate I can see is this one. https://www.texas-speed.com/p-5002-t...-camshaft.aspx Very popular around here and on the performance truck boards for 5.3 motors.
Buy the push rod checker tool. DO NOT buy push rods until after your engine is assembled. DO NOT "assume" anything about push rod length, you will almost certainly regret it.
[QUOTE=RB04Av;20217608]The Crane lifters are probably just fine; although if you haven't bought them yet, look at these. http://rpmspeed.com/gm-performance-ls7-lifters/ Those guys also have a ported LS6 oil pump sometimes; might have to call and ask. Otherwise use the Melling 10296. They also have timing sets. You don't need anything radical, if your gears are still good you can just replace the chain http://rpmspeed.com/ls1-gm-ls2-timing-chain/.
I think the cam you want seems reasonable, but for a larger motor in a lighter vehicle. Not sure why you want a Lunati cam in particular, not that there's anything wrong with them, just, they may or may not offer "the right" thing for what you're doing. IMO you'd do better with a smaller one that that in your application, unless you have ALOT of converter and/or gear. The most likely candidate I can see is this one. https://www.texas-speed.com/p-5002-t...-camshaft.aspx Very popular around here and on the performance truck boards for 5.3 motors.
Buy the push rod checker tool. DO NOT buy push rods until after your engine is assembled. DO NOT "assume" anything about push rod length, you will almost certainly regret it.[/QUOTE
I ended up buying some oem lifters from lunati and 269/281 cam cloyes timing chain push rod length checker borrowed from a friend and can someone tell.me what I'm looking for in springs not just wich ones would like recommendations on wich ones aswell tho I got fell pro gaskets comp cam locking plate cam install grease engine break in fluid regular flow oil pump and I dont mean to make this a full engine talk i am going to completely go through this engine and replace everything what is the highest performing piston style?
First LS cam I bought was from Lunati. They told me to get springs for .650 lift. I did but we had a 651 lift cam. I said are you sure this will be enough spring for that cam because I really didn't want to be on the edge. I was told it will be perfect don't worry. I got the best Hyd lifters they had that were supposedly Morels. They also told me we could rev it to 7400 no sweat. Told us to set the rev limiter to 7400 and shift at 7000. We drove this around lightly putting 80 miles on it not ever going over 6000 to break it in good.. First time we took it to 6800 it ate a valve, tore up the head and block. After tearing it apart we noticed the cam was already showing signs of wear having a grove cut into every lobe and the rollers on the lifters wear pretty tore up with only 80 miles. You couldn't give me another Lunati cam. Do yourself a favor and order a cam from cam motion. It won't cost anymore and they can tell you what springs you need. You will be very happy you did.
You already know what springs to buy, But you probably won't. You'll buy something inadequate and then come back posting here about some valve train problem or other. Probably either making noise, or doesn't RPM even to where it did stock.
You're not going to like that cam with a stock converter; it'll have MUCH less bottom end than stock. Soggy.
Best piston style to buy is a flat-top. Problem is, by the time you buy all that and work up the block and do whatever all else, you coulda just gone to the junkyard and got a low-mile LQ9 which will RUN CIRCLES around some 5.3, and had less money in it. Spend more, get less. Not my idea of how to enjoy a hobby.
But you're gonna buy what you've already decided you're gonna buy, and not listen to anything anybody here has to say. Not to be mean or anything but we've all seen it a million times on all the performance car forums. Good luck.
You already know what springs to buy, But you probably won't. You'll buy something inadequate and then come back posting here about some valve train problem or other. Probably either making noise, or doesn't RPM even to where it did stock.
You're not going to like that cam with a stock converter; it'll have MUCH less bottom end than stock. Soggy.
Best piston style to buy is a flat-top. Problem is, by the time you buy all that and work up the block and do whatever all else, you coulda just gone to the junkyard and got a low-mile LQ9 which will RUN CIRCLES around some 5.3, and had less money in it. Spend more, get less. Not my idea of how to enjoy a hobby.
But you're gonna buy what you've already decided you're gonna buy, and not listen to anything anybody here has to say. Not to be mean or anything but we've all seen it a million times on all the performance car forums. Good luck.
I'm sorry sir alot of people dont take advice. I have no claim to knowing alot about the internals. But I so ask people who do and value there opinions alot more than most I will explain my choices far and 99% of stuff I've chosen was recommended from someone that knew more than I ok I chose that cam because I know it needs a new converter to run at it's best but can run on stock that's why I chose it it was recomend for that reason I'm slowly building it and driving it I cant afford all these things at once I'm not going to be pulling anything with this I'm not gonna be doing much off road cause accation might go down a trail or 2 but it's more street applications I've just got my intake and exhaust to accommodate it that was recommended and on this thread I have not ordered them yet but 1218 springs is the best referral I've seen I am still open recommendations on brands that's spring specs are similar to those but my 1% of the choice is the brand I get I dont know what the specs should be in them or how to find that out kinda my question was figure out with springs and how you come up with the specific spring to get I understand a little more now but I think I will understand more tomorrow when my cam comes in and I see the specs on it that's recommended really I'm not to worried about finished hp I'm trying to learn more about them so thank you for your piston recommendation will look more into them that's my next step of stuff to start learning about and wanted a place to start research I've read so much about valvetrain and cams I need a break from that and start learning my next step I am looking at a set if refurbished 799 heads what would be the gains and or losses of them on my lm4 and money is just a thing k dont care if just buying a 6.0 and doing stuff to it is way more for my money cause I'm just trying to learn and end up with something I can say I built.
You already know what springs to buy, But you probably won't. You'll buy something inadequate and then come back posting here about some valve train problem or other. Probably either making noise, or doesn't RPM even to where it did stock.
You're not going to like that cam with a stock converter; it'll have MUCH less bottom end than stock. Soggy.
Best piston style to buy is a flat-top. Problem is, by the time you buy all that and work up the block and do whatever all else, you coulda just gone to the junkyard and got a low-mile LQ9 which will RUN CIRCLES around some 5.3, and had less money in it. Spend more, get less. Not my idea of how to enjoy a hobby.
But you're gonna buy what you've already decided you're gonna buy, and not listen to anything anybody here has to say. Not to be mean or anything but we've all seen it a million times on all the performance car forums. Good luck.
in
Idk this just really pissed me off I try to be respectful but you shouldn't even be on this website commenting with that kind of attitude I am proud of my work and value peoples advice I just changed that engine by myself in the gravel driveway took me 2 weeks rained most of it put put a canopy over it and kept working I took my time cleaning every single part I to spotless painted the engine got infection in my hand half way through from smashing it finished it one handed with no help an all that I did so far has been recommended not my list to to out and just buy it cause it shiney I used all hand tools no air tools cleaned 90$ of the parts with a rag to spotless i take pride in what i do and dont just take the easy way cause ite faster no I got a damn good looking truck my hand might be little worse for wear but I had a great time doing it and learned I want to learn more about my engine and continue working on it I dont even know exactly what my end goal is with it other than to learn everything I can about it
First LS cam I bought was from Lunati. They told me to get springs for .650 lift. I did but we had a 651 lift cam. I said are you sure this will be enough spring for that cam because I really didn't want to be on the edge. I was told it will be perfect don't worry. I got the best Hyd lifters they had that were supposedly Morels. They also told me we could rev it to 7400 no sweat. Told us to set the rev limiter to 7400 and shift at 7000. We drove this around lightly putting 80 miles on it not ever going over 6000 to break it in good.. First time we took it to 6800 it ate a valve, tore up the head and block. After tearing it apart we noticed the cam was already showing signs of wear having a grove cut into every lobe and the rollers on the lifters wear pretty tore up with only 80 miles. You couldn't give me another Lunati cam. Do yourself a favor and order a cam from cam motion. It won't cost anymore and they can tell you what springs you need. You will be very happy you did.
Sonething is amiss her . That doesnt sound like Lunati and I have done lots of business and hours of discussions with them over the last few years
Idk this just really pissed me off I try to be respectful but you shouldn't even be on this website commenting with that kind of attitude I am proud of my work and value peoples advice I just changed that engine by myself in the gravel driveway took me 2 weeks rained most of it put put a canopy over it and kept working I took my time cleaning every single part I to spotless painted the engine got infection in my hand half way through from smashing it finished it one handed with no help an all that I did so far has been recommended not my list to to out and just buy it cause it shiney I used all hand tools no air tools cleaned 90$ of the parts with a rag to spotless i take pride in what i do and dont just take the easy way cause ite faster no I got a damn good looking truck my hand might be little worse for wear but I had a great time doing it and learned I want to learn more about my engine and continue working on it I dont even know exactly what my end goal is with it other than to learn everything I can about it
relax, it's just the internet.
hopefully this means you won't be tearing into it before you learn how to do stuff.
prepare to read on forums and sites for like... a year. or two. and then throw out maybe 80% of what you read.
hopefully this means you won't be tearing into it before you learn how to do stuff.
prepare to read on forums and sites for like... a year. or two. and then throw out maybe 80% of what you read.
I research it as much I can then start I got a buddies who knows there stuff and has done it all before i have to drag out there to show me half the time its something simple and I'm overthinking it but i but am not gonna do something or put it together and be unsure if I did something wrong I'll find someone who knows and have them show me but I atleast try to research and watch videos enough to not just sound stupid but there is nothing like doing it yourself compared to reading and watching it
Sonething is amiss her . That doesnt sound like Lunati and I have done lots of business and hours of discussions with them over the last few years
I didn't just come on here to make up a story. I talked to them a lot too. They told me what spring pressures to get and I got them in double Pacs. When I called them after this happened and all they said was you must have gotten a bad spring. In the pictures you can see that many valves had hit the pistons. What, I got all bad springs? I doubt it. The motor was built by a professional engine builder too. How do you explain how bad the lobes and rollers on the lifters were all tore up. I tought it may be the engine builder so I took it to a very well respected builder to see if they had done anything wrong. They told me all the machine work was very good and the valves were adjusted properly too, so it wasn't from them. We have Jessel shaft rockers on top too. Then they changed to, you must have over revved it. The tell tale on the Autometer Tach said 6800rpm. So you tell me what happened. When I ordered this cam I explained to them I wanted to hit it eventually with a 300 shot too. Does this look like a nitrous cam to you? Lived and learned the hard way at my expense. You can clearly see that those 2 exhaust valves hit the pistons along with several others.
I didn't just come on here to make up a story. I talked to them a lot too. They told me what spring pressures to get and I got them in double Pacs. When I called them after this happened and all they said was you must have gotten a bad spring. In the pictures you can see that many valves had hit the pistons. What, I got all bad springs? I doubt it. The motor was built by a professional engine builder too. How do you explain how bad the lobes and rollers on the lifters were all tore up. I tought it may be the engine builder so I took it to a very well respected builder to see if they had done anything wrong. They told me all the machine work was very good and the valves were adjusted properly too, so it wasn't from them. We have Jessel shaft rockers on top too. Then they changed to, you must have over revved it. The tell tale on the Autometer Tach said 6800rpm. So you tell me what happened.
When I ordered this cam I explained to them I wanted to hit it eventually with a 300 shot too. Does this look like a nitrous cam to you? Lived and learned the hard way at my expense.
You can clearly see that those 2 exhaust valves hit the pistons along with several others.
Maybe fly cutting was needed. The valve reliefs weren't deep enough.
The piston to valve was confirmed to be more than enough. This is why I took it to a different builder to have them make sure everything the first builder did was correct. Besides we ended up going to a much larger solid cam after that and it ran fine. Same pistons. All that ended up fixing it was putting in heavier springs. Remember we had 80 miles on it taking it to 6000rpm many times with no problem. It surely would have hit during this, if that was the case. Then the first time we decided to take it to 6800 and boom. That motor was a LQ4 and after trying to get some help on redoing the motor the original builder said we over revved it too. They said we could rev it to 7400 no sweat as well. As you can see i covered all the bases to make sure it wasn't the builder to stop any type of, he said she said. We went with the second builder and used a Dart Next block now and are very happy with the new motor. Same pistons with a way bigger cam. No fly cutting required. We don't normally, but have revved this motor to 8000 with no problem. We pulled it apart this year just to check things out after spraying the **** out of it many many passes, and were pleasantly surprised to find the bearings to still look like we just assembled the motor new. Rings, pistons, and bore looked fine too. So we put it back together not changing a thing for this year. Borowski did a Great Job on this motor. Couldn't be happier. All we ended up doing to it this year was a lot more port work on the adaptors for the intake, and I mean a lot. She should really make some steam this year. They were pretty badly choked down. We only spent a few minutes on them the first time and was shocked how much we took out of them this time. A half inch off the floor entry and like an eighth inch off the rest of the way around. Can't wait to see what it does this year.
The piston to valve was confirmed to be more than enough. This is why I took it to a different builder to have them make sure everything the first builder did was correct. Besides we ended up going to a much larger solid cam after that and it ran fine. Same pistons. All that ended up fixing it was putting in heavier springs. Remember we had 80 miles on it taking it to 6000rpm many times with no problem. It surely would have hit during this, if that was the case. Then the first time we decided to take it to 6800 and boom. That motor was a LQ4 and after trying to get some help on redoing the motor the original builder said we over revved it too. They said we could rev it to 7400 no sweat as well. As you can see i covered all the bases to make sure it wasn't the builder to stop any type of, he said she said. We went with the second builder and used a Dart Next block now and are very happy with the new motor. Same pistons with a way bigger cam. No fly cutting required. We don't normally, but have revved this motor to 8000 with no problem. We pulled it apart this year just to check things out after spraying the **** out of it many many passes, and were pleasantly surprised to find the bearings to still look like we just assembled the motor new. Rings, pistons, and bore looked fine too. So we put it back together not changing a thing for this year. Borowski did a Great Job on this motor. Couldn't be happier. All we ended up doing to it this year was a lot more port work on the adaptors for the intake, and I mean a lot. She should really make some steam this year. They were pretty badly choked down. We only spent a few minutes on them the first time and was shocked how much we took out of them this time. A half inch off the floor entry and like an eighth inch off the rest of the way around. Can't wait to see what it does this year.
There was not enough PTV clearance.
Now you have a bigger cam and it works, well you can add .250 lift and change the valve opening and closing times and it can provide a ton of clearance. That cam card you have pictured says a lot. the exhaust closes 23.5 degrees after tdc, the intake opens 19.5 before tdc.
It didn't break right away because with dome top pistons the valve hit flat, if it was a flat top piston it would have hit the valve on the edge and been a problem first time.
Most reputable shops won't throw other shops under the bus. The most important thing to say, read this carefully. If the first builder didn't do anything wrong why did he put inadequate valve springs in it? The second shop didn't say anything about the first shops mistake of installing weak springs? Hmm. What did he do just trust the specs off the box? Didn't check the actual spring rate? Someone fucked up. You can't say it was Lunati's fault, someone put the wrong springs in it if thats what you're claiming the problem was. It looks like lack of piston to valve clearance. So someone fucked up right? Who do you think it was?
03-02-2020, 08:03 AM
Valve springs 
