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Shaolin Crane 02-25-2015 03:24 PM

Quote:

Originally Posted by Vettezuki (Post 138726)
I get your point, I guess it's relative. I'm beyond OE for sure, but pretty moderate compared to nutters. FTM my LS1 lifters (and rockers) look 100% fine. I'll bring it up again and make sure we're on the same page.

My primary failure was a rod bearing, that's what was making noise and best guess indicates a detonation precipitated the impending failure. Pulling it apart we discovered (so far) a broken ring and a chewed up cam. Previously it was an AM spring that popped. Unless I'm forgetting something, nothing OE in the valve train failed or even looks tired. :huh: It's not a lot of money difference, so that's not my concern here, but spending a few hundred dollars extra for nothing more than a little more valve train noise in reality doesn't appeal to me either.

I'll say it again, you're not going to a solid roller, you're staying hydraulic, noise should not increase at all. My injectors are louder than the lifters are, you're having a reputable shop doing the work, so I would expect them to install them with the proper preload and pushrod length.

If a portion of the cam was chewed up, and not the lifters that means the lifter was collapsing at some point and bouncing on the cam or the push rod was flexing. Link bars won't collapse, so no float, etc. Lifter failure is usually for extended consistent RPM, usually doesn't matter at what RPM. 20 seconds at 4k is riskier than 3 seconds at 7k.

I'm all for saving money, but, the valve train is not the place to do it. So either run a cam that will match with the LS7 parts, or run stuff that matches the larger cam.

I'm just offering advice, you can take it how you please.

Shaolin Crane 02-25-2015 03:27 PM

Quote:

Originally Posted by Vettezuki (Post 138728)
This is all I've found. It's not the lifter so much but people just plain configuring their valve train wrong. How many LS7 lifters fail in stock LS7s after even many hard miles? Not many that I'm aware of. The max lift on a stock LS7 is like .590~ and they spin up to 7k.

Those lifters are paired with a measly 100lb valve spring, make sure that is noted. Lifters, are paired to spring pressure, as noted in my earlier post.

Ryridesmotox 02-25-2015 03:33 PM

Actually... Plenty. My budget may dictate that I have to run LS7s and that's fine for a while to me, but eventually I'll be going with linked bars, they are better.

It depends more on the lobe design from what I understand. If you have a very aggressive ramp rate. The lifter and pushrod can lose contact with the cam lobe (because spring pressure isn't matched well. Its all about how the valvetrain is designed as a whole.

Edit: As a side note, a few of my buddies that work on vettes bought tons of the older sets of LS7 lifter. Apparently the early lifters are better. The newer ones are more failure prone and are said to be the replacement for all LS lifters. That's just their personal experience.

Shaolin Crane 02-25-2015 03:38 PM

Quote:

Originally Posted by Ryridesmotox (Post 138731)
Actually... Plenty. My budget may dictate that I have to run LS7s and that's fine for a while to me, but eventually I'll be going with linked bars, they are better.

It depends more on the lobe design from what I understand. If you have a very aggressive ramp rate. The lifter and pushrod can lose contact with the cam lobe. Its all about how the valvetrain is designed as a whole.

Exactly, .550 and up cams have more aggressive ramp rates, more aggressive ramp rates need more spring pressure, run more spring pressure you need a lifter that can handle it, which means you need a pushrod that can handle it.

So either go with LS7 everything. Cam, lifters, pushrods and valve springs, or, use data supplied from cam specs and build accordingly. If you have a lifter failure, you cannot just pop the intake off like with a SBF or SBC.

Vettezuki 02-25-2015 06:26 PM

Ugh. One more day. Kinda getting tired of this aspect of car hobby.

Ryridesmotox 02-25-2015 06:56 PM

Quote:

Originally Posted by Vettezuki (Post 138738)
Ugh. One more day. Kinda getting tired of this aspect of car hobby.

This too shall pass. I'm still probably 2-3 weeks out. The waiting is the hardest part.

Vettezuki 02-27-2015 03:08 PM

Block is ok at 3.908, max over.

Thanks Ryder, but won't be needing that L76.

Piecing together the package now. Going to keep stock displacement (mostly to avoid the cascade of costs that follow stroking), but will go with forged rods as well as pistons. Pistons will have a light dish to drop CR to between 10.5 and 11.0, depending on what's available.

Remaining head remains to be seen.

Ryridesmotox 02-27-2015 03:26 PM

Cool dude. Keep us posted on the build.

Vettezuki 03-04-2015 04:24 PM

Coming together. May be able to pick it up next week.

Heads and block checked out so far, which means the little bit of coolant that was in no. 1 is a mystery. Troy said he's seen one case where there was a little leak between the liner and block when the engine heated up. Unfortunately, that's not so easy to check for.

A new cam is being ground for it according to my behavior requirements. Not sure what the final specs are yet though.

Will put in H beam rods along with the forged pistons, so when all is said and done, motor should be good for a dead reliable 600WHP or so, which I have no intention of going to with this motor, so a big margin of safety.

With the -4cc dish and my heads, and stock gasket CR will come in at around 10.7 or roughly a half point drop. Everything should work fine with my tune until I get headers at which point I'll go for a full re-tune. That'll be about it for this motor. Probably come in somewhere around 420-430WHP, on a smoggable street friendly 346ci~ NA motor. Not bad.

94cobra69ss396 03-05-2015 08:06 AM

Who's doing your cam?


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