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Discussion Starter #2,884
I had the following maintenance work done 1 day ago after driving 80 miles and now I’ve developed a P0301 cylinder 1 misfire code on my way home from work:

1. Timing belt tensioner was seeping oil so it was replaced

2. Water pumped replaced since it was leaking a little coolant

3. Replaced several underhood fuel lines since they were leaking a little

4. Radiator pipes replaced with silicone pipes

The IAG stage 4 shortblock has 45k miles on it. The IAG stage 5 heads/272 kelfords have 110k miles on it

I drove the car 40 miles home after the maintenance work and 30 miles to work the next morning, no issue, coolant perfect temp, oil and fuel pressure perfect. I was cruising home after work and as I got off the highway the car died and wasn’t able to idle or start up. The diagnostics ran by the shop showed spark plugs and injectors all working fine and compression test was perfect. They are now pulling the motor to see if it is a bent/burnt valve issue.

My question is, is this a freak occurrence with it happening in such close timely as all the maintenance work (granted the heads have a ton of miles) or was it something that had to do the maintenance work?
 

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110k miles is not a coincidence imo.
But dont get greedy haha, minor rrpair. Hopefully.

Good quality build with no corners cut and ongoing monitoring and maintenance. Plus, unlike what people think, big turbo and dd is more reliable than a medium sized one. How often and how long it remains on boost is reduced unless you want to be doing 200km/h on your way to work. Also majority of the load is in high engine speed which is healthier.

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Bad valve and perfect compression?
All those leaks on your car? Added: I meant reported leaks . . . I mean afterr all these years . . . - It always seemed that you of all people have kept a real car in perfect driving condition.


If I were you I think I'd find a flat bed.
 
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Hmmm so the car had a cyl 1 misfire, car died while driving shortly after repairs and wont start up. Is it possible that they messed something up while doing the timing belt tensioner? Did they do a leakdown test? It just seems kind of odd that the engine has good compression but theyre going to pull it anyways and inspect valves.

Given the miles and modds a bent/burnt valve seems possible but if it were me, pulling the engine and removing the heads is the last thing id want to do. Id be checking everything else, including the simple small stuff like grounds.
 

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Discussion Starter #2,893
they suspect it could be an electrical issue since I had that engine fire back in 2017 from a power steering line blowing. They are waiting for wire harness to come in



they haven’t pulled motor yet since the compression test was perfect so hopefully it is just an electrical issue :)
 

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Discussion Starter #2,894 (Edited)
We found the culprit of the cylinder 1 misfire and it is a broken GSC valve spring resulting in a bent valve :( the IAG Stage 5 head casting, Manley valves, Kelford cams have 110k on them. Oddly the GSC beehive springs I had for 45k miles when the heads were refreshed during closed deck install. Anyone have stories of broken GSC beehive valve springs?



 

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Discussion Starter #2,896
What a shitty ass way for my motor to go. The Manley valve springs were perfect when I had the closed deck installed and that was with 60k miles on them. I’m going with the a Ferrea valvetrain for my new motor. They do have way less google hits for “valve spring failure” on google when compared with GSC beehive valve springs. It is the fine line I walk with driving daily on a built motor but come on, I only rev this motor to 8k with just 272 cams, the last part I would expect to fail would be a damn valve spring while coming off the highway.

The closed deck still had perfect compression after pushing 38psi-40psi for 45k miles on them. There was slight scoring along the cylinder walls but zero cylinder crack :) the JE pro seal head gasket and Oring held up like a champ after all these years!
 

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+1 for the Ferrea valvetrain, my heads have been rock solid with 4+ years of 30psi 8000rpm thrashing. A lot of race/track events in that time too. Not at your power level but still sustaining the rpm.


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Discussion Starter #2,898
JJ and Rick said that Ferrea is the creme de la creme when it comes to valvetrains with their titanium construction :) I only knew that a couple months ago lol I would have had gone with them for the start!
 

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Do you have the spring specs when the closed decking was done? Curious to see if there was indications that one spring was testing lower.

Was it GSC or Manley? You said both :p

Farrea is a good brand we used to solely use them. GSC quality has improved over the last few years as well. I don't think I've ever used Manley valve train components.

Good news is that the failure could have been far worse! If that valve snapped it would be a lot more $ to fix.

how is the scoring going to be addressed? Bore/hone an upsize the pistons? Assuming it's going to be addressed while everything is torn down.
 

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Discussion Starter #2,900
Unfortunately I don't have the spring specs :(

I had Manley valve springs for around 60k miles when I got the closed deck installed. During that time the heads were refreshed with new GSC beehive valve springs. I'll be getting a whole new longblock from IAG since the heads and cams themselves are pretty old and I think I got enough life out of the shortblock after 4 years. The new longblock will be pretty much the same except for a Ferrea valvetrain and I am looking forward to the additional security of the new Firelock headgasket :)
 
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