Ralls

I have been going over in my head lately what I'm going to do with my current engine. I have a boosted 383 LT1 with Eagle forged crank, eagle h-beam rods, eagle forged pistons, splayed caps, head studs, etc. Made 643hp. I only have about 350 miles on my engine before something let loose at the track. It runs fine except for the massive blow-by, white smoke out the exhaust, and loosing coolant. I have yet to tear it down but I'm expecting piston damage.

So here is my dilemma. At the VERY LEAST, I'm going to have a machine shop:
-Replace the pistons with something high end (JE)
-All new bearings
-Re-do the cylinder walls because I have had excessive blow-by since the beginning.
So with those things alone the machine shop, I assume, would need to basically start from scratch by blue printing, replacing seals and freeze plugs, and machine everything again.

I'm not sure how much all of that would cost me to have done, but I'm thinking it would be cost effective and less stressful to just buy a built motor from somebody. If need be, I can transfer over my cam, valvetrain, timing set, oil pump, or whatever else.

Here is one of many choices I would be willing to buy https://www.camaroz28.com/forums/sho...ht=short+block
My next goal is 800+hp. I would feel better with ditching all my eagle stuff while I'm ahead.

Blownbird355

Depends on money and time. Did you build the 1st one or a machine shop? Was it dyno tuned? Sounds like you made some good numbers, with the blow by sounds like piston prob of some sort. May just need new pistons and bearings and a good cleaning.

roguedriver

How do you know you didn't just push a head gasket or crack some ring lands, or both? I wouldn't make any decisions until you find out whats going on first. Do a leak down, find the dead cylinders, pull the heads and take a look. I cracked 2 pistons on low mileage. Ordered a new set of JE's and rings, did a quick hone on the cylinders, put it back together and its been running like a champ for thousands of miles.

Ken R.

Ralls

I have a habit of making quick decisions... and spending lots of money on this car. I feel like it's going to cost a lot to have a machine shop freshen up everything and replace at least the pistons with JE's. I've been told by several engine builders that my cylinders must be out of round due to the blow-by (blow-by before it actually broke at the track).
I look at it this way. I spent about $4,200 in just the short block materials and machine work. That was also with me doing the assembly. I don't have the patience to build a short block again so I would rather pay a reputable shop to do it. So I figure since all those parts have to be replaced aside from the crank and rods, it's probably going to cost a couple grand.

I'm just thinking out loud. As time goes by, I expect more and more out of my car. And because of that, I start to see the weak points like my chinese eagle crap. I want to o-ring the block this time around too. It just seems easier buy someone else's hard work if it's going to cost about the same.

RealQuick

That shortblock you linked to Jerry's thread... that is a steal.

Ralls

Yeh it's a good deal.
I called the machine shop I plan on dealing with and they told me I would have about $2,700 with just replacing the pistons, machining, and bearings. So I might as well buy Jerry's shortblock if it's still for sale..

blown94

Ok, not to offend you or anything, but like has been stated already, you dont know what you got until to inspect it for issues. Since you put it together the first time, and it had blowby since the getgo, I would first question your ability to build an engine, especially for boost. Like I said, no offense, but everyone thinks you just bolt **** together and its easy as pie. I would first look at the piston rings you used and see if you installed them correctly and with the correct gap. Did you just use normal ring gaps for an NA engine, or were the rings properly gapped/installed? Did you have adequate crankcase ventilation, or were you pressurizing the crankcase causing what you think was blowby? Loosing coolant could be the result of improper head gasket installation, a bad tune, or who knows what else. Theres just way too little info on a fairly new engine with multiple issues to just condemn the whole engine as junk, especially if the engine had no blowby in whatever form it was b4 you built it.

xxsaint69x

hope you are getting 2000 dollar pistons with that quote lol

Ralls

I would probably say the same thing if I was someone else reading this. I can only attest for my own workmanship and that I did the best I could. This wasn't some backyard throw-it-together build. I worked side by side with a machine shop in PA for months building it with the intention of boost. They did all the machinery work while I saved money by doing things like clearancing the block, weighing parts for balancing, porting heads/intake, and assembly. All under their guidance and supervision. Whether I did something wrong or they did, that's in the past.

My engine slowly developed blow-by. I have a vented catch can with -10AN lines running off my valve covers. The unburnt gases coming out of the vent just got worse over time. Then I started loosing oil out of multiple seals. The last time I really drove my car was at the track when it failed on me. I don't know if this caused it or not, but I ran low on gas and had to fill up at the track with unleaded 100octane considering it was tuned at 93 octane.

As far as $2,700 to rebuild and replace the pistons. That includes a whole tear down, machining, and the shop doing the whole assembly. Not sure what other shops around the country would charge but don't overlook the fact I live in one of the highest cost of living areas in the country. I could easily find a cheaper place but I was recommended this particular shop because of their LT1 knowledge.

I do appreciate the responses whether I'm getting berated or not. I'm just looking at this from a different view. Should I rebuild the current engine and possible find more damage that I expected; or buy a new short block with better parts and have it ready when the warm weather hits?

xxsaint69x

why not tear it down your self and bring them all the parts? Worse case scenario you will need a rehone, new pistons/rings and some new bearings....now way it should cost anywhere NEAR 2700, unless u are getting some crazy pistons.....

roguedriver

I'd be willing to bet it will cost you under $1000 to fix it yourself. You won't know for sure until you tear it down, but i would assume new pistons, rings and rod bearings (probably don't need crank bearings). You could get lucky and its just a ring issue. If thats the case, way cheaper cause you won't need to spend on pistons. If you need pistons, you can get just what you need if its an off the shelf piston and match the weight to the other pistons. Like blown94 said, there are things that need to be set up for boost vs NA. What did you set the ring gaps to? They need to be larger then a NA setup. If not, the heat will close them up and you'll damage the rings, or worse, the pistons. Check if you put the rings in right when you take it apart. Did you space out the ring gaps when you put them in? The leaky seals means the crank case is pressurizing. Probably a result of an issue in the cylinder (rings, pistons or both). How do you have your pcv set up? How much timing are you running? Assuming your rings are just bad or even pistons damaged, if your cylinders look good, you should just need to hit the cylinders with a ball hone and put new pistons, rings and rod bearings in there. Look at the old rod bearings and see if they've been beaten up from it detonating. Leave the rest of the engine in tact. Put new head gaskets in it and get them torqued down correctly. You'll probably be good just with that.

Ken R.

Ralls

I guess it doesn't sound so bad looking at it like that.

I would of torn this motor down a long time ago but I've been trying to get other things straight first.
I bought a two post lift for my garage and now I'm trying to coat my garage floor so cleaning up oils would be easy. I'm basically spending $4K just to WORK on my car

I can't remember what I gaped the rings to. I wrote a lot of my specs down on a note pad but for some reason I never wrote that. I remember it being pretty wide, like 0.030 maybe. My machine shop had a whole method to positioning the rings. Top and bottom 180* apart and the oil rings being in specific spots. It's been about 4 years since then. My stock pcv is eliminated. Just a vented catch can off the valve cover.

slomarao

try another machine shop

blown94

I dont believe thats going to be adequate for over 10psi. You need some sort of vacuum on the catch can and add a breather iff necessary. Seems to be a common issue with higher boost. Boost itself will create excess crankcase pressure and it needs to be dealt with or you'll never keep oil in the engine.

Im running a 3/8 hose from each cover to a Y, then off to the catch can and on to the suck-side of the supercharger. It works fairly well but I think I need to go a tad larger. Stock pvc system still in place for normal idling and driving. I did have to swap out the pvc valve as the old one started leaking boost into the crankcase. Worked well on the 350. See how it goes with the 383.

Some guy are running exhaust bungs to suck the pressure out of the case. Its another option for you to look into. I say tear the engine down yourself and pay close attention to what you may have done the first time around.

Ralls

This weekend I decided to drop the engine. Tore everything down to the short block. The oil has water in it. The head gasket looks messed up on the passenger side mostly. Tell me what you think happened here.


In this picture is looks like the gasket was pushed outwards.


This looks like the gasket is distorted and not straight up.




I don't see damage to the pistons from the top either.