is this a good valvetrain upgrade?
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is this a good valvetrain upgrade? I am building a forged 5.7L w/stock crank looking for about 10-12psi. I am going with either a set of LQ4 heads if I can find them at the right price, or the stock 5.7L heads. Either will have a home port/polish.
Would upgrading to an LS6 spring be stiff enough? How about pushrods - would the LS6 work too or is there a better unit out there for the price? As for now I will be running the stock cam and staying between 6200 and 6500rpms. I know that FI puts more load on the springs and I don't want the valves touching the pistons EVER! Pistons will be flat tops if I find a set of LQ4 heads and dished if I go with the stock LS1 heads.
Thanks! -Dave
Would upgrading to an LS6 spring be stiff enough? How about pushrods - would the LS6 work too or is there a better unit out there for the price? As for now I will be running the stock cam and staying between 6200 and 6500rpms. I know that FI puts more load on the springs and I don't want the valves touching the pistons EVER! Pistons will be flat tops if I find a set of LQ4 heads and dished if I go with the stock LS1 heads.
Thanks! -Dave
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I'm thinking 12lbs of boost will blow a lot of fuel/air through those valves even on a stock cam... it will also give me great low-end torque characteristics. Even at the higher RPM's I still think it will push enough through. Would a Z06 cam be better?.... don't know what overlap is like on it.
Originally Posted by mdhmi
I wouldn't think spinning your motor to 6500 RPM with a non Z06 cam would be worthwhile.
Why build a forged motor with a stock cam?
Mark
Why build a forged motor with a stock cam?
Mark
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What are 918's, cast iron? Why would I want cast iron heads??
Originally Posted by 8KickassRS9
lq9's theyre aluminum, and go with 918's. that way if u decide to go with a decent custom cam u wont need to switch em out again.
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What are 918's, cast iron? Why would I want cast iron heads?? I don't think having LQ9's is going to hold me back as far as a different cam is concerned.
Originally Posted by 8KickassRS9
lq9's theyre aluminum, and go with 918's. that way if u decide to go with a decent custom cam u wont need to switch em out again.
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for starters if youre going to do the Valvetrain do it right....Double Valve springs like from Comp Crane etc and get either hardened/Chromoly pushrods and Titanium retainers for weight savings so the motor will rev a bit faster.And i believe 8Kick.... meant COMP 918's as in springs.And all LQ4/LQ9 heads after 00 were aluminum i believe.And id recommend getting a cam,even a babe cam like a LPE GT2-3 or something a bit more...itll idle great give you more power and good drivability.just my 2 Cents.
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Yea, if I was going all out that's what I'd do... but I just don't think the cost for a set of aftermarket springs ($150) is worth the benefit over Z06 springs ($50). I can think of better ways to spend that $100... and I am pretty sure the Z06 pushrods could handle the job, but maybe there's a cost effective alternative?... especially with a 6500rpm max redline.
You're right about the LQ4/JQ9 heads.
I don't think I'd want to go much farther from a Z06 cam, mostly because I want to keep a very responsive low-range for city driving, smooth quiet idle and once again, price.
Sorry to sound like a penny-pincher guys... would build it to the hilt if I could... just want to get the most out of a small budget!
You're right about the LQ4/JQ9 heads.
I don't think I'd want to go much farther from a Z06 cam, mostly because I want to keep a very responsive low-range for city driving, smooth quiet idle and once again, price.
Sorry to sound like a penny-pincher guys... would build it to the hilt if I could... just want to get the most out of a small budget!
Originally Posted by ddnspider
for starters if youre going to do the Valvetrain do it right....Double Valve springs like from Comp Crane etc and get either hardened/Chromoly pushrods and Titanium retainers for weight savings so the motor will rev a bit faster.And i believe 8Kick.... meant COMP 918's as in springs.And all LQ4/LQ9 heads after 00 were aluminum i believe.And id recommend getting a cam,even a babe cam like a LPE GT2-3 or something a bit more...itll idle great give you more power and good drivability.just my 2 Cents.
as far as i know the pushrods are the same as ls1 pushrods,why not spend $75 and get good ones.Speaking from experience ive snapped more than 1 and its not pretty.look into the LPE GT2-3 cam...LPE has said that they use Z06 springs with not problem and you can get an extra boost in HP...im making 370ish right now with stock heads and that cam on motor.And you hear no lope!there are things you can chince on to save money and then there are things you shouldnt cut corners on.Better be sure on your parts b4 you regret it.
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Ya know, the more I think about it, I guess a set of comp springs aren't a bad investment considering the damage a swallowed or bent valve can cause.... that might be one place where $150 is well spent, especially after spending $2k on forging your shortblock. $75 for a set of pushrods isn't bad.... I could live with that.
I'll have to price that cam and see where I stand.
I like to do things right the first time, but this stuff adds up fast... and everyone knows what I'm talking about!
I'll have to price that cam and see where I stand.
I like to do things right the first time, but this stuff adds up fast... and everyone knows what I'm talking about!
Originally Posted by ddnspider
as far as i know the pushrods are the same as ls1 pushrods,why not spend $75 and get good ones.Speaking from experience ive snapped more than 1 and its not pretty.look into the LPE GT2-3 cam...LPE has said that they use Z06 springs with not problem and you can get an extra boost in HP...im making 370ish right now with stock heads and that cam on motor.And you hear no lope!there are things you can chince on to save money and then there are things you shouldnt cut corners on.Better be sure on your parts b4 you regret it.
Cam $350 = 30-40 more HP $10 per HP if you are a cheapskate then it doesnt get cheaper than that for power.
Also 918 springs and hardened pushrods are cheap compared to a mishap and at your projected HP target a great idea even if you dont intend to rev higher than 6500.
Also if you are going to run 12psi then I would say no matter what heads you use why not go with dish pistons either way?? Low compression is your friend. I run LQ9 heads and dish pistons and I am around 9.5 to 1 I think and my car is still a beast out of the hole even with a loudmouth on it.
What are you doing for air charge cooling??
Anyway good luck with the project!
Also 918 springs and hardened pushrods are cheap compared to a mishap and at your projected HP target a great idea even if you dont intend to rev higher than 6500.
Also if you are going to run 12psi then I would say no matter what heads you use why not go with dish pistons either way?? Low compression is your friend. I run LQ9 heads and dish pistons and I am around 9.5 to 1 I think and my car is still a beast out of the hole even with a loudmouth on it.
What are you doing for air charge cooling??
Anyway good luck with the project!
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Yea, a cam will probably be in my future as well hahaha... just don't want to lose that low end driveability...
Yea, I did rethink what I originally said about the valvesprings and pushrods... cheap insurance.
Pretty sure flat top pistons and LQ9 heads will get me down around 9.2:1 compression ratio... I will look into that after I test-fit the engine in my Jag... to amek sure I have room for an FI setup.
As far as charge cooling is concerned, I'm going to buy the parts for an A2W intercooler setup... I hate to start saying this stuff (and I never had on this board) but my uncle is a phenominal welder.... I was at his shop when he got a new welder and he was welding aluminum foil together with neat little lines... pretty crazy.
Thanks, I am getting my pieces slowly... just bought a set of LQ9 heads I am going to start polishing... and I bought a 4L80E trans a couple weeks ago... I'm about halfway done refinishing my leather interior... it's slowly coming together!!
Yea, I did rethink what I originally said about the valvesprings and pushrods... cheap insurance.
Pretty sure flat top pistons and LQ9 heads will get me down around 9.2:1 compression ratio... I will look into that after I test-fit the engine in my Jag... to amek sure I have room for an FI setup.
As far as charge cooling is concerned, I'm going to buy the parts for an A2W intercooler setup... I hate to start saying this stuff (and I never had on this board) but my uncle is a phenominal welder.... I was at his shop when he got a new welder and he was welding aluminum foil together with neat little lines... pretty crazy.
Thanks, I am getting my pieces slowly... just bought a set of LQ9 heads I am going to start polishing... and I bought a 4L80E trans a couple weeks ago... I'm about halfway done refinishing my leather interior... it's slowly coming together!!
Originally Posted by libertine1015
Cam $350 = 30-40 more HP $10 per HP if you are a cheapskate then it doesnt get cheaper than that for power.
Also 918 springs and hardened pushrods are cheap compared to a mishap and at your projected HP target a great idea even if you dont intend to rev higher than 6500.
Also if you are going to run 12psi then I would say no matter what heads you use why not go with dish pistons either way?? Low compression is your friend. I run LQ9 heads and dish pistons and I am around 9.5 to 1 I think and my car is still a beast out of the hole even with a loudmouth on it.
What are you doing for air charge cooling??
Anyway good luck with the project!
Also 918 springs and hardened pushrods are cheap compared to a mishap and at your projected HP target a great idea even if you dont intend to rev higher than 6500.
Also if you are going to run 12psi then I would say no matter what heads you use why not go with dish pistons either way?? Low compression is your friend. I run LQ9 heads and dish pistons and I am around 9.5 to 1 I think and my car is still a beast out of the hole even with a loudmouth on it.
What are you doing for air charge cooling??
Anyway good luck with the project!
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Yea that's what I was looking it... put me around 9.2:1..... I'll figure all that out when I get the forged rods and pistons because I still want to get down around 9:1.
Originally Posted by ddnspider
underthe LS1 internals section there was a list of CR with what cc heads...but its off a bit....with just LQ9 heads you get about 9.5ish:1
i know exactly what thread youre talking about,its a sticky.Its not exactly correct,i had a thread about it and someone jumped in and set me straight,it'll be .2ish higher,then factor in your gaskets as well.
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I was A2A all the way, but with this Jag there's very limited space up front for an effective IC setup... A2W will be much easier to package and I am confident a water setup will do just fine.
Originally Posted by ddnspider
for a street car get an A2A and LQ9 heads alone i dont think will drop you that much with no dish...id see about 9.5:1 the lowest CR you'd achieve with just the heads.
