LIPSTICK's 800hp first LNF compound turbo/engine build!
those are some nice numbers. good to see this project get done (as done as any project car anyways).
your bang on with the valve spring issue, not enough spring pressure for the boost levels. i had a similar issue with my l61 i built many years ago, it had bates 94 lb springs. when i swapped the motor into my 944 after it sat for years it ran out of power at 6500, reving it higher and the power curve just went flat. increasing the boost 2psi and the power flattened out at 6000, 2 more psi and it flattened at 5500. the springs were just dead from sitting. with a fresh set of springs it makes power up to 8000 rpm.
your bang on with the valve spring issue, not enough spring pressure for the boost levels. i had a similar issue with my l61 i built many years ago, it had bates 94 lb springs. when i swapped the motor into my 944 after it sat for years it ran out of power at 6500, reving it higher and the power curve just went flat. increasing the boost 2psi and the power flattened out at 6000, 2 more psi and it flattened at 5500. the springs were just dead from sitting. with a fresh set of springs it makes power up to 8000 rpm.
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From: RI
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From: RI
those are some nice numbers. good to see this project get done (as done as any project car anyways).
your bang on with the valve spring issue, not enough spring pressure for the boost levels. i had a similar issue with my l61 i built many years ago, it had bates 94 lb springs. when i swapped the motor into my 944 after it sat for years it ran out of power at 6500, reving it higher and the power curve just went flat. increasing the boost 2psi and the power flattened out at 6000, 2 more psi and it flattened at 5500. the springs were just dead from sitting. with a fresh set of springs it makes power up to 8000 rpm.
your bang on with the valve spring issue, not enough spring pressure for the boost levels. i had a similar issue with my l61 i built many years ago, it had bates 94 lb springs. when i swapped the motor into my 944 after it sat for years it ran out of power at 6500, reving it higher and the power curve just went flat. increasing the boost 2psi and the power flattened out at 6000, 2 more psi and it flattened at 5500. the springs were just dead from sitting. with a fresh set of springs it makes power up to 8000 rpm.
i wonder if those Bates 94 lb springs will fit LNF head?
Will the heavier springs prevent the lash adjusters from collapsing? I would worry about that as much as valve float. Sounds like solid ones would be a great idea on this motor. How much would 100lb springs impact the life of the timing chain?
the bates springs arent available anymore, however supertech does make a 94lb spring set. im willing to bet if you already are running the whole supertech spring kit (springs, retainers, locks, etc) you can just get the stronger springs.
lash adjusters could become an issue, but then again they might not. the 94lb springs are roughly 17 lbs more on the seat and 15lbs open, thats not a huge increase. now consider the boost levels, 45psi pushing down on the valve (intake valves are roughly 1 square inch surface area) and the spring pressure doesnt sound so high. the lash adjusters become a problem at high rpm with stiff springs, but in this case i dont feel it would be a problem.
in my l61, the 94 lb springs were overkill but thats all that was available at the time (around 2006-2007). the engine only ran to 7000 rpm at 12 psi and had stock cams, the car it was in just couldnt take anymore. in this iteration i never felt it had any lifter collapse occurring. when i put the engine into the 944 i also put in a set of cams and solid lash adjusters as i planned (and do) rev it to 8k.
lash adjusters could become an issue, but then again they might not. the 94lb springs are roughly 17 lbs more on the seat and 15lbs open, thats not a huge increase. now consider the boost levels, 45psi pushing down on the valve (intake valves are roughly 1 square inch surface area) and the spring pressure doesnt sound so high. the lash adjusters become a problem at high rpm with stiff springs, but in this case i dont feel it would be a problem.
in my l61, the 94 lb springs were overkill but thats all that was available at the time (around 2006-2007). the engine only ran to 7000 rpm at 12 psi and had stock cams, the car it was in just couldnt take anymore. in this iteration i never felt it had any lifter collapse occurring. when i put the engine into the 944 i also put in a set of cams and solid lash adjusters as i planned (and do) rev it to 8k.
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Thank you for the feedback guys.
i currently have the taller lash adjusters provided by ZZP for their stage 2 camshafts.
Couple of questions:
1.) will these taller lash adjusters be affected even worse using stiffer springs such as the 92lb supertech?
2.) my current big concern is actually the plastic timing chain guides. Besides the stronger timing chain guide bolts that can be bought....the weakest link is the plastic guides. Have u guys remedied that issue?
3) how about the adjustable timing chain tensioner? Do you guys use adjustable? Or converted it to manual?
4.) stiffer valve springs will probably cause even more stress & failure to both the plastic timing chain guides and adjustable chain tensioner?
i currently have the taller lash adjusters provided by ZZP for their stage 2 camshafts.
Couple of questions:
1.) will these taller lash adjusters be affected even worse using stiffer springs such as the 92lb supertech?
2.) my current big concern is actually the plastic timing chain guides. Besides the stronger timing chain guide bolts that can be bought....the weakest link is the plastic guides. Have u guys remedied that issue?
3) how about the adjustable timing chain tensioner? Do you guys use adjustable? Or converted it to manual?
4.) stiffer valve springs will probably cause even more stress & failure to both the plastic timing chain guides and adjustable chain tensioner?
Last edited by SKY888; May 19, 2018 at 11:02 PM.
cant really comment on the taller lash adjusters, never even knew that was a thing. although that leads me to think zzp is using reground cams with a smaller base circle instead of grinding cams from new blanks, and if thats the case wow do they charge a lot of money for their cams.
im running all stock guides and bolts, no issues so far. i think the bolts are the biggest problem. most just run the updated gm chain tensioner, the manual adjust tensioner is a race only huge power thing.
i dont think the stiffer springs will cause issues with anything, i havent experienced any failures, granted this engine doesnt have that many miles on it (in 10 years it may have had 10,000km put on it, but it got beat on all the time). i wouldnt expect to see the timing chain and guides last 100,000 miles, but the likelihood of a high strung 4 banger seeing that much mileage is slim.
im running all stock guides and bolts, no issues so far. i think the bolts are the biggest problem. most just run the updated gm chain tensioner, the manual adjust tensioner is a race only huge power thing.
i dont think the stiffer springs will cause issues with anything, i havent experienced any failures, granted this engine doesnt have that many miles on it (in 10 years it may have had 10,000km put on it, but it got beat on all the time). i wouldnt expect to see the timing chain and guides last 100,000 miles, but the likelihood of a high strung 4 banger seeing that much mileage is slim.
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cant really comment on the taller lash adjusters, never even knew that was a thing. although that leads me to think zzp is using reground cams with a smaller base circle instead of grinding cams from new blanks, and if thats the case wow do they charge a lot of money for their cams.
im running all stock guides and bolts, no issues so far. i think the bolts are the biggest problem. most just run the updated gm chain tensioner, the manual adjust tensioner is a race only huge power thing.
i dont think the stiffer springs will cause issues with anything, i havent experienced any failures, granted this engine doesnt have that many miles on it (in 10 years it may have had 10,000km put on it, but it got beat on all the time). i wouldnt expect to see the timing chain and guides last 100,000 miles, but the likelihood of a high strung 4 banger seeing that much mileage is slim.
im running all stock guides and bolts, no issues so far. i think the bolts are the biggest problem. most just run the updated gm chain tensioner, the manual adjust tensioner is a race only huge power thing.
i dont think the stiffer springs will cause issues with anything, i havent experienced any failures, granted this engine doesnt have that many miles on it (in 10 years it may have had 10,000km put on it, but it got beat on all the time). i wouldnt expect to see the timing chain and guides last 100,000 miles, but the likelihood of a high strung 4 banger seeing that much mileage is slim.
The stage 2 LNF cams need the taller lash adjusters which come when u purchase the cams. But the stage 1 on the other hand uses stock lash adjusters.
so I dont know if these taller ones will be affected with 94lb springs.
i already have arp timing bolts and the biggest bolt is from Jeff reilland/mongorat. So I think Ill be ok with those. Just concerned w/ the plastic guides.
my first adjustable chain tensioner failed, and caused the timing chain to skip a tooth or two a couple of years ago, but Im glad the internals survived & no major damage. So, thats my other concern moving forward using my new tensioner.
Ugggghhhh lots of concerns lol
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The taller lash adjusters are just stock LDK lash adjusters from what I've heard before and my bet is zzp grinds blank cams also sky you can go with a happy medium instead of jumping from 75lb to a 94lb just going with zzp springs 82lbs or OTTP 85lbs I believe they are
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im just afraid that getting either 80 or 82lb springs might not be enough, & I wasted buying them & paying somebody to install them. Then will realize Ill need the 94lb, u know?
About the taller lash adjusters used for the stage 2 cams, I didnt know that theyre stock LDK units?
there isnt much difference between a 75 lb spring and an 80 or 82 lb spring, your talking 2-7lb on the seat and 10lb open. it might help a little, but i think its just going to move the point the car noses over up a little. for most people the 75-82 lb springs are enough, but most people arent running 45 psi.
myself, i wouldnt bother upgrading unless your going to put the 94lb springs in.
myself, i wouldnt bother upgrading unless your going to put the 94lb springs in.
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there isnt much difference between a 75 lb spring and an 80 or 82 lb spring, your talking 2-7lb on the seat and 10lb open. it might help a little, but i think its just going to move the point the car noses over up a little. for most people the 75-82 lb springs are enough, but most people arent running 45 psi.
myself, i wouldnt bother upgrading unless your going to put the 94lb springs in.
myself, i wouldnt bother upgrading unless your going to put the 94lb springs in.
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there isnt much difference between a 75 lb spring and an 80 or 82 lb spring, your talking 2-7lb on the seat and 10lb open. it might help a little, but i think its just going to move the point the car noses over up a little. for most people the 75-82 lb springs are enough, but most people arent running 45 psi.
myself, i wouldnt bother upgrading unless your going to put the 94lb springs in.
myself, i wouldnt bother upgrading unless your going to put the 94lb springs in.
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