Hello, Everyone

I made an amateur move buying a 2001 C5 with seems to be a beautiful build. Had a shop look it over and was tokd it was in good shape. Car drive fine is fast but after 1st day if owning it I opened the gas cap to feel pressure blowing back at me, so I believe there has to be at lease some ring land damage and who knows what else.

The build is an ECS procharger utilizing its own oil, 1050x Injectors by dynamics, Race tronix return fuel system + hot wire kit, walbro 450 fuel pump, mighty mouse wild catch can (which needs new filter asap), Mantic street clutch ER MS 1001, RMCR tune base in Colorado springs) I'm in New Mexico so roughly same elevation here of about 5200ft, Breathless stepped long tube headers, corsa sport mufflers, and c5 z06 rear end, manual transmission.

In three days we are going to open the heads up to see what's really going on but like I said blow back just from opening the oil cap, and serious blow by out of catch can. It's basically shooting oil into catch can on every short drive.

Sadly blew most my budget buying the car that still needs tires but any and all advice at what I shoukd be looking for once we are in the heads and do some compression tests would be great. Being where going to have to crack her open its time to use the ol credit card and upgrade some internals, the question is what internals should be essential? Please ask me for any info you need and I'll know more coming this next Monday too hopefully. I was told the car was set at 11psi and the dyno sheet showed 565whp and about 550ft pounds of torque in 2020 after the procharger had been rebuilt.

I'd like to run the car safely with close to 600whp for a year but since I'm in there build it to handle closer to 800whp when and if I want to turn up one day, which ofcourse ill want to @BLOWNBLUEZ06 (heard blownblue06 is the man if happen to be around

Thank you all for listening and I look forward to hearing back. Kind regards.

 

Moved to C5 Tech.

 

Thank you

 

Engine toast broke a ring land on one of the pistons. How did u not know that when bought??

 

The car still drives amazing and as I said in the the post I paid a shop for compression test and inspection I took there word for it. I also said a ring land must be busted. How did you not know that from reading what I wrote? ( see how that feels, not good right), so sorry about that wasted time everyone.

Can we start over please Obviously I need to get in the engine, I was thinking of using this kit from summit https://www.summitracing.com/parts/S...7/applications

How do I make sure motor is able to handle a rebuild? What should I ask of the next shop that is going to help me, I'll be taking it somewhere else ofcourse, I live in New Mexico. I am feeling terribly stuck due to lack of my own knowledge and having the first place I took it completely lie or not know about vehicles condition. Can anyone offer some good advice please? If it is just a busted ring land would that kit work from summit, and how to I make sure the engine is up to accepting new parts? I know I must seem ignorant, but this why I am here trying to learn and asking for help. Talk all the crap you'd like, if you could just sneak in advice with it I would I will be forever grateful.

 

This part of the world is backorder for coffee.

 

You won't know what you need till you get the heads off

 

Fair enough, thank you. I will touch base early next week with update.

 

Probably barking up the right tree.

But before you tear it down, please verify one thing which SO so many people get wrong and make sure the MMS catch can routing is set up correctly. Some people reverse it. Others add limiters and one-way restrictors. You never know. Or even try removing it back to stock and see if the pressurization goes away. Probably not your problem, but worth verifying first.

Early on you said gas cap - if the gas tank is pressurizing then the release valve needs service

Oil cap - like I said, probably barking up the right tree re ringland.

How long have you had the car since the inspection and purchase? The shop which inspected it might be liable. However, if you've been driving it ... and it sounds like SC life and mechanical work is somewhat new to you... they will likely be able to back away from any claims on basis of who knows what the operator did while driving? For all they know you're out there missing shifts or doing neutral drops and running it on 87 at redline.

A VERY REAL caution on the snowball effect and projects. Before you buy ITEM ONE, have a firm goal in mind of what you want and do not waver. If the thing is toast, I'm going to say right here and right now that your best bet is one of two things and then leave it be. Either swap in a junkyard 5.3 and be done. Or grab a pre-fab shortblock or longblock from one of the larger vendors like Texas Speed. There are many others out there. Doing this skips parts supply issues and labor problems and gives you some warranty typically. Get it. Get it in. Be done. Especially since, forgive me, but you sound mechanically partially aware and not fully mechanically experienced from the way it has read so far. Might not be the case, just how it sounds.

Overall, GOOD LUCK.

 

Hello, and thank you for your response it is appreciated. As you mentioned the mechanic shop gave full push back to my complaints about the compression tests. I am running 91 octane and did plan on meth kit just for cooling and higher octane for detonation purposes, don't plan on tuning it for meth for any HP gains. Thus is all post poned right now ofcourse.

Had new compression test and driver side was all in acceptable range with little variances. On the passenger side all but cylinder 1 had horrible compression roughly in the 60s on three cylinders. We are doing a leak down test this Monday. Hoping a gasket replacement would help if leak down test passes but not holding my breath. Also when looking into catch can connections everything is set up correctly however the PCV valve has been deleted, the hose was gunked up bad so cleaning that ofcourse. Even though catch can is correct any recommendations on putting a certain pcv back in series with catch can or leave as is?

You are correct I'm mechanically inclined but not to the extent of doing any type of head work or claim to be an all around solid mechanic by any means. I found a used ls1 low mileage engine out of a 2004 gto with 100 day warranty or 1000 miles whichever comes first, any thoughts? I'm not jumping on that until we investigate further with leak down test, if leak down test passes , think it's worth a try replace gaskets being its all on one side of block that compression was bad?

It means alot for you to chime in with your experience and being cordial. I look forward to any other thoughts and suggestions as we figure this out. Thank you

 

You can also look into the 5.3 truck motors as an option if you need to.

 

Definitely good to know. Currently only running 10psi of ecs d1sc procharger and happy keep it in the 600whp range, thinknthe 5.3L would be fine to handle the bit of biost im putting in it?
​​​​Thanks for joining the conversation Smoken1.
From what I see I don't think my current setup with procharger would work with the 5.3. Correct me if I'm wrong. Nice to have you all to talk to.

 

Hehe, the 5.3 is THE go to for a cheap boost base. Gap the rings and go to town. The block is stronger. And that 327 is s hot ticket.

 

Well that is exciting being I could get that block cheap and put some forged components on before installing.

Forgive me for not knowing this I assumed I would need a different procharger than what I own which is ECS 1dsc, is that not that case, and my current manual trasmission will bolt up to the truck engine as well? Same ecu also, assuming a tune? Any help with direction would be fantastic.

 

Don't jump the gun you still haven't taken your old engine apart to see whats up with it

 

I agreeI absolutely . Hard not to get over excited and start searching the earth right away. I'll update you all what I find out through the week.
All great info, good people! Be well and talk soon.

 

Many here remain uninitiated to the joys of Sloppy Mechanics. Check out Matt's yt channel for starters, but he's got two fb pages public and private (public is just for the more dopey humor stuff) and the web oage has proven build combos and base tune files.

Debate the long term durability, but they regularly push junkyard LSs with gapped rings to 600, 800, 1000rw on cheap turbo combos.

Not saying that's the way to go. But that the factory guts can handle a lot of squeeze.

 

Alright. So leak down test passed great without compression increasing.
Also got some fluid to test and make sure to exhaust gas was in the coolant. So where should I go from here? Dig into the head? The car runs really good just alot of blow by and oil consumption. Head gaskets, and valve covers, or take head to machin shop? Comments welcome

 

Alright. So leak down test passed great without compression increasing.
Also got some fluid to test and make sure to exhaust gas was in the coolant. So where should I go from here? Dig into the head? The car runs really good just alot of blow by and oil consumption. Head gaskets, and valve covers, or take head to machin shop? Comments welcome

 

My next step would be pull that head and thoroughly inspect it. Inspect the cylinder bores while you have it apart.

OTOH if it's running well enough for your usage now you could continue saving and looking for the components you want. Be prepared for the car to grenade at the worst possible moment and take out expensive parts when it does. Best case you line up all your future parts, park it and have the work done before anything terrible happens.
Check everything frequently and be as gentle as possible to maximize your chances of it surviving until you're ready.
Good luck!