Been down this road myself. What is the condition of the injectors (if efi)? I would check to make sure you don't have one hung open. Even with all the gaps aligned it's going to hold more than 30#.

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Do a leakdown on it to see exactly where the problem is.

 

Leak down is next but I wasnt sure it would be necessary since I can hear it in the crankcase. I can just about play the flute using the lifter valley drain back holes.

I'll check the injectors. They have sat unused for a while. Have to see if there's anyone local that can clean and flow them for me.

 

Switch the injector to a different cylinder.

 

I can do that as well but really need to get this blowby figured out. Injectors, intake, etc aren't going back on yet unless I decide to just run it more and see if it clears up. I don't have much faith in that though, I don't expect to get out of this so easily. I hope I do, but I can already see me having to pull the motor back out and take it to the builder.

 

That motor is coming back out. Sorry to say that.

 

Don't switch the injector to a different cylinder. If its stuck open you'll have 2 dead holes. If you're running a stock fuel rails, pull them it of the intake, put a solo cup under each injector, and cycle the key a few times. You'll know if it's leaking or not.
If it is, you probably washed the rings out. Drop the pan, pull the slug out, toss a new set of rings in and let it bump

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I hear ya, dropping the pan on these is about as much of a pain as it is to pull the motor though. Something to think about though. I appreciate the ideas.

 

Yea, I'm afraid that is going to be the case. Would there be any reason to put the intake back on and try running it again for a bit or is that just wasting time and effort that should be used to pull it?

 

I can't see any reason to put it back on. I would check that injector out first thing.

 

Broken ringlands can't see it from the top. Something bad happened . Pull the engine.

 

I just hooked up the fuel lines to the intake and primed the pump. No leaks anywhere.

 

If I were in your position (paid to have the shortblock built) I would take it out and bring it to them at this point. Give them the opportunity to fix it. If they end up giving you resistance over it, plan on at least pulling that piston out and having a look at it. I can't think of a reason it would have busted a ring land like that. Best case scenario is a ring may have been damaged during installation and just broke. Either way, if they ask you to continue running it, I'd find someone else to build for you in the future. If the ring wasn't seated after the first minute or 2 (I'm assuming moly faced rings) it's never going to seat.

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Stuck injector could wash a second cylinder. I'd start by doing what firebird_1995 said. You sure don't want to pull the engine and fix it, only to have it happen again.

 

Just did that, none of them are leaking but I'll probably get them serviced while the shortblock gets figured out and fixed. Seems like I'll have plenty of time to get it done. I won't even have time to pull the motor for a couple weeks I think.

 

Yes, they are moly rings. I haven't called them and told them about the compression numbers yet. I only called them when it first started the excessive blowby. They just said that some blowby is expected until the rings are seated and recommended running to operating temp 4 times and they should be fully seated by then. I'm just going to do as you guys recommend and pull it and take it to them so they can tear it down.

Another problem I see is I'm using an old piston that isn't available anymore, trw L2441. Even the later speed pro L2441 wasn't identical. I might be looking for a new set if I got damage to ringlands :-(

 

Crazy that you're mention that piston, I ran the same ones in my first blown 355 lt1. They didn't last long though. That ring pack leaves a lot to be desired. Good thing is, they are plenty heavy so if/when you upgrade to a better piston, you'll have plenty of weight left on the bob-weights to keep from having to buy mallory

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I know I'm getting pretty far ahead of things but in the off chance I do have to get a new set of pistons, what would be a good replacement for these.

This is just a street car, stock crank with eagle h beam rods, ported stock heads, mild cam. The Vortech SC v1 s-trim is non-intercooled.

 

Were the ring gaps set up for a power adder or N/A ?

 

I am not sure but the builder was informed that it would be supercharged.

 

IMO - You can do a leakdown if you wish just for the sake of gathering more information but if the cylinder is reasonably round the rings will seal well enough without ever running to not have the situation you are describing. There is something physically wrong and it will not be fixed by continuing to run the engine.

 

Going to pull it back out first chance I get. Will post up what we find. Thanks for all the input. Just wish these cars weren't so damn cramped and a pain to get to EVERYTHING. Really sucks to get everything done just to run into an issue like this, sigh...

 

Yeah, it sucks. Sorry that it happened on a fresh setup. I'm curious what you find out. For some reason I'm thinking my set weighed 549 grams with rings. The 5/64, 5/64, 3/16 rings probably accounted for 49 of that. I'd say your options are wide open for pistons in the future. I've had reasonable success with boost under 15# on srp 4032 pistons. I've pushed a few over the edge and now I'm switching to mahle 2618 -31cc dish.

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Well, I finally got around to pulling this motor back out and getting it back to the builder. They called today and said that every piston had the rings stuck so badly that some cannot be removed. They also said that all 8 pistons were galled so badly that it looked like they came out of a 300k mile motor. Pistons are scrap now. It's going to need to be re-honed, new rod/main bears and a new set of pistons and rings. The crank is also going to need a polish. The only smoking gun they found to cause all this on an engine that only ran twice for under 15 minutes total was a heavy smell of fuel in the oil. They think it was dumping fuel and washed down all 8 cylinders which I believe is a fair assessment based on the damage.

At first I thought maybe it was an injector problem but then I remembered one thing but I am not sure if this would do it. For break-in, the builder suggested I remove the supercharger so I pulled the charge pipe off but I did not remove the FMU. Would the FMU have caused it to dump this much excessive fuel? I have checked the injectors and none are leaking.

 

it's a builder problem period.

Needs new pistons that FIT the bore once the bore is corrected. If the cylinders are galled, it will require a new bore/hone fitted to the new pistons....

A simple hone job and new pistons do not sounds like a fix.

 

So, This isn't something I may have caused by over-fueling with the FMU still hooked up? I was given the impression that it was likely washed down so badly that nothing was getting oiled in cylinders

 

sorry for the above--which I waited to long to correct---

It should say

"If the cylinders are galled, it will require a new bore/hone fitted to the new pistons...." Not pistons fitted to the bore---sorry!"

 

Make sure the rings had the right radial width .

 

as an machinist-engine builder- no one "wants" to admit when something they did goes sour.. Its a tough racket.. But if its true, you only ran it 15min- and even if it was crazy rich-- to do that much damage that fast.. I don't think so.. sounds like the shop needs to help you out.. Plus it leads me to tink they did'nt know what they are doing by letting you run a boosted engine with those old heavy power-forged slugs.. Thats a recipe for disaster in itself..

 

I hate to think that as they've always done good work for me in the past, going back 15+ years. I can't blame them for the piston choice either, this was a previously running combo that I picked up and brought to them for the rebuild. I know the pistons weren't ideal but I am selling the car so I wasn't too concerned since I knew the previous history of the combo when it ran with the old owner. When I say I ran it for 15 minutes, I am being pretty generous, honestly it may have been 10.

Was the supercharger on it before and running correctly? FMU only raises fuel pressure under boost. I guess its possible to be stuck maybe? Never seen one though. Measure fuel pressure with the engine off and fuel pump running. Should be base pressure. It would have run you out of the garage if it was running that rich.

The first time I fired the engine, the supercharger was hooked up. Ran good for a few minutes before I noticed the blow-by from the dipstick tube. It was at the point I stopped and called the builder. This is when they recommended that I disconnect the SC and try to get the rings to seat NA. I pulled the charge pipe off but left the FMU hooked up. The FMU wasn't seeing boost so it shouldn't have had any effect if I am understanding correctly. Base pressure was correct at 43.5 and oil pressure always looked great. It was a little rich but not to any extreme.

They have agreed to cover the re-hone and all of the labor but I will have to cover the parts. I am going to take it another direction so I'll need to find another piston set to run around 12.5:1 and 250-300 of nitrous. Looking at 2618 alloys and h13 pins.

 

Was the supercharger on it before and running correctly? FMU only raises fuel pressure under boost. I guess its possible to be stuck maybe? Never seen one though. Measure fuel pressure with the engine off and fuel pump running. Should be base pressure. It would have run you out of the garage if it was running that rich.

 

I need to run by and pickup the cam that was in it. I'll try to get some pictures of the damage and maybe a part number for the ring package that was installed.