Smashed intake valve seals
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Smashed intake valve seals I went to change my valvesprings to replace some Patriot Gold Duals and on the passenger side I had 3 smashed or destroyed valve stem seals.
All the others are perfect and none of the exhausts were damaged.
Is this a sign the springs were just getting more worn out than I expected or some other issue?
Cam is an EPS 230/238 with an EPS intake lobe at .605" and the exhaust is the lsl at .615" (if I remember correctly). I have been turning it around 6700rpm. Heads were only milled .010" and I am using a 7.4" pushrod with older style Vortec 350 lifters which require more preload, a shorter pushrod results in a severe loss of power and insanely bad valvetrain noise.
All the others are perfect and none of the exhausts were damaged.
Is this a sign the springs were just getting more worn out than I expected or some other issue?
Cam is an EPS 230/238 with an EPS intake lobe at .605" and the exhaust is the lsl at .615" (if I remember correctly). I have been turning it around 6700rpm. Heads were only milled .010" and I am using a 7.4" pushrod with older style Vortec 350 lifters which require more preload, a shorter pushrod results in a severe loss of power and insanely bad valvetrain noise.
sounds like they have been walking around on the seats a lot...
do the seats match the springs? does the inner side of the spring fit nicely with the spring seat lip?
it could also just be the inner spring is just not big enough to clear the valve seal properly(too tight of a fit)
or it could be a function of harmonics throwing the spring around, and you just need a spring with more pressure and control
do the seats match the springs? does the inner side of the spring fit nicely with the spring seat lip?
it could also just be the inner spring is just not big enough to clear the valve seal properly(too tight of a fit)
or it could be a function of harmonics throwing the spring around, and you just need a spring with more pressure and control
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the old springs were the patriot gold duals with matching retainers, locks, and seats but they do have around 20-25k miles on them, car never showed signs of valve float and I was in a tight spot getting rid of my exes car so I have been broke and finally could afford to replace them
while it's not very scientific or precise I did try to compress them by hand and the couple that had bad seals feel slightly softer to compress between my palm and concrete floor, going to have them tested out of curiosity later
replaced them with Tooley's new springs meant to work with the patriot retainers/seats, everything felt like it fits great and it does seem like the top end is a little quieter running now, haven't been able to drive it due to snow/ice so I have just been letting it run up to operating temp and then cool to help heat cycle them in
while it's not very scientific or precise I did try to compress them by hand and the couple that had bad seals feel slightly softer to compress between my palm and concrete floor, going to have them tested out of curiosity later
replaced them with Tooley's new springs meant to work with the patriot retainers/seats, everything felt like it fits great and it does seem like the top end is a little quieter running now, haven't been able to drive it due to snow/ice so I have just been letting it run up to operating temp and then cool to help heat cycle them in
I had 2 or 3 smashed valve seals on my GTO when I was running a Torquer v3 cam with 650 PRC springs. That cam had a 643 lift. It would burn a little oil after a high rpm run, but only with that setup.
My valve seals on my Trickflow heads that were completely set up by TEA never had ANY problems as you can imagine. Never burned oil with that setup.
I imagine it was the seals, the springs, or install error with the Tv3 setup that was the cause of the problem. I never figured it out. I bet lots of people are running around with a damaged valve seal or two.
My valve seals on my Trickflow heads that were completely set up by TEA never had ANY problems as you can imagine. Never burned oil with that setup.
I imagine it was the seals, the springs, or install error with the Tv3 setup that was the cause of the problem. I never figured it out. I bet lots of people are running around with a damaged valve seal or two.
When springs are shot they tend to oscillate quite a bunch when the high rpm harmonics wreak havoc on them. Old singles use a damper, beehives have an inherent shape to control this motion without a damper, and duals rely on each spring as well as elevated pressure to control surge. I'm also betting that the Patriots weren't shimmed to within .060" of coil bind at full lift. Most people don't do this and just feel that a .650" spring must be more than adecuate for a .600" lift cam, however being .100"-.110" from coil bind allows surge and then the inner tends to "break dance" all over the seal. while your 6700 rpms doesn't seem real high...keep in mind that the spring is trying to control a valve that is opening and closing(hopefully without bounce) more than 55 times per second....jeesh....
That happened with my Patriot golds on TRex cam...I had started to notice valve float and had been planning to replace them anyways. Running BTRs now and got rid of the Rex...
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Could be in my head but the engine seems to be happier. Not "faster" really or anything like that, just seems to run smoother through the RPM and if I wasn't nearly certain it was placebo I would say it might be revving a little snappier.
Either way, I'm pleased and if the weather cooperates will be hitting the track Sunday. The last 2 times I went to the track the car slowed down about a tenth from my best even though the DA was better. Curious to see if it picks back up. My 1/8th mile times were close but the back half seemed lazy.
Either way, I'm pleased and if the weather cooperates will be hitting the track Sunday. The last 2 times I went to the track the car slowed down about a tenth from my best even though the DA was better. Curious to see if it picks back up. My 1/8th mile times were close but the back half seemed lazy.
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Could be in my head but the engine seems to be happier. Not "faster" really or anything like that, just seems to run smoother through the RPM and if I wasn't nearly certain it was placebo I would say it might be revving a little snappier.
Either way, I'm pleased and if the weather cooperates will be hitting the track Sunday. The last 2 times I went to the track the car slowed down about a tenth from my best even though the DA was better. Curious to see if it picks back up. My 1/8th mile times were close but the back half seemed lazy.
Either way, I'm pleased and if the weather cooperates will be hitting the track Sunday. The last 2 times I went to the track the car slowed down about a tenth from my best even though the DA was better. Curious to see if it picks back up. My 1/8th mile times were close but the back half seemed lazy.
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Went back yesterday. The track was slick as snot so there was no using first gear at all even on fresh MT ET Streets at 17 psi.
1/8th MPH was still down at 91-92mph (down from high 93-mid 94s)
1/4 MPH was still down at 112-113mph (down from 114s and a couple rare 115s)
Going to try changing out the o2 sensors, they've been slow switching and my fuel trims are going rich. Also going to clean the MAF really well and double check the tune.
It's not possible the valves could have beat up the seats enough it would hurt flow but still seem to run fine is it? It seems unlikely to me.
The car definitely shows signs of being down 15rwhp or more. The DA yesterday was great at 450-460ft.
1/8th MPH was still down at 91-92mph (down from high 93-mid 94s)
1/4 MPH was still down at 112-113mph (down from 114s and a couple rare 115s)
Going to try changing out the o2 sensors, they've been slow switching and my fuel trims are going rich. Also going to clean the MAF really well and double check the tune.
It's not possible the valves could have beat up the seats enough it would hurt flow but still seem to run fine is it? It seems unlikely to me.
The car definitely shows signs of being down 15rwhp or more. The DA yesterday was great at 450-460ft.
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Heads are now off as I'm trying to swap to an LS2 shortblock. Tooley springs have about 7000 miles on them now.
I found one more smashed valve seal.
Guess once the heads are finished being ported and the re-installed on the engine I will try to shim them and see if that stops it for good. Never really done it before, is the process fairly simple?
I found one more smashed valve seal.
Guess once the heads are finished being ported and the re-installed on the engine I will try to shim them and see if that stops it for good. Never really done it before, is the process fairly simple?
Heads are now off as I'm trying to swap to an LS2 shortblock. Tooley springs have about 7000 miles on them now.
I found one more smashed valve seal.
Guess once the heads are finished being ported and the re-installed on the engine I will try to shim them and see if that stops it for good. Never really done it before, is the process fairly simple?
I found one more smashed valve seal.
Guess once the heads are finished being ported and the re-installed on the engine I will try to shim them and see if that stops it for good. Never really done it before, is the process fairly simple?
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Ah, well not interested in getting into who makes what or anything.
Surely it's something wrong with my setup as plenty of people run these without issue with more aggressive cam lobes than my 230 duration .600 lift EPS lobe.
Cam is being redone as a Cam Motion 230/238 .62x/.602 113+3 and should be here next week so I can start setting up the LS2 to prepare for transplant.
Surely it's something wrong with my setup as plenty of people run these without issue with more aggressive cam lobes than my 230 duration .600 lift EPS lobe.
Cam is being redone as a Cam Motion 230/238 .62x/.602 113+3 and should be here next week so I can start setting up the LS2 to prepare for transplant.
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pushrods are 7.4 Comps, just the typical hardened ones like everyone runs
valves are stock 799 valves
lifters are older style that came from a Vortec 350 (it was an emergency and I learned they interchanged just take more preload), I had tried shorter pushrods to loosen the preload before but the engine hated that...sounded like the top end was full of rocks so the 7.4s went back in
everything runs great and no signs of float (engine was still down on power as noted above) but whatever was wrong will be gone now...new shortblock, new cam, new lifters, new timing chain, and heads will get a good valve job as part of the more extensive porting
valves are stock 799 valves
lifters are older style that came from a Vortec 350 (it was an emergency and I learned they interchanged just take more preload), I had tried shorter pushrods to loosen the preload before but the engine hated that...sounded like the top end was full of rocks so the 7.4s went back in
everything runs great and no signs of float (engine was still down on power as noted above) but whatever was wrong will be gone now...new shortblock, new cam, new lifters, new timing chain, and heads will get a good valve job as part of the more extensive porting
Btr springs are FROM associated spring where patriot got their springs. He can sell you a new set of springs that will drop right in.
Last edited by Jason 98 TA; Jan 11, 2015 at 03:38 PM.
