jrz28camaro

Ok so a couple of weeks ago I blew the head gaskets and when I was cleaning every thing up my mechanic, and I noticed that the pistons had .030 on them so that makes my motor a 355ci which had perfect cross hatching on the cylinder walls that was a nice suprise

so the real question is should this change my cam choice I was looking at the cc503 but now I am wondering if a cc306 would be doable now or would the extra cubs not make a bit of difference?

the heads are unported so they are stock but completely rebuilt i.e. new valves 3way valve job, cc918 beehive valve springs, cc 1.6 mag rr's.

so is the cc 306 to big still or dose the added cubes make it unsaleable now?
thanks in advance

RamAir95TA

The five extra cubes don't make a difference. You might want to check the stroke too - maybe you've got a 383.

95zsean

I build a 355 last year and used a GM847 and it's a but hard to drive slow....but what a Monster when you get on it. if your using it as a daily driver I'd use the 503, i had one in my stock engine with a set of LE2 heads and all the bolt on stuff and loved it. If i remember I made 310RWHP on a Dyno Jet. It LOVED the Nitrous too....

96capricemgr

So many LT1s are built so badly I would be disappointed to find .030 on the pistons. Even many "performance built" LT1s are a step backwards, if the rebuild on this one was not even mentioned when you bought it then it was likely an attempt at a "stock rebuild" which is almost always a big step backwards.

"rebuilt" heads with new valves just screams taking your money rather than competent work. Stock valves and valvejob are just fine. I would trust the stock valvejob over most local shops.

I would just inspect what you have reuse whatever you have and always keep it in the back of your mind that what you have might fall apart.

I know this is not the warm fuzzy reply you wanted but I am serious, most basic local rebuilds are worse than stock. Far as crosshatch, normal to find that on a 200K mile stock shortblock. It isn't an old engine with a carbslow to warm up washing all the oil off the walls letting the rings wear the bore

jrz28camaro

but my mechanic slash friend who has been building race engines for 40 years was the one that inspected it I trust him with my life on this subject. he was showing me were the piston rings come to the top of the stroke or the ring landing their is zero ring wear at all. but about the pistons them selves the 030 marking on the top of the piston was stamped on and they have a 4 valve relief on them I know for sure they are just a basic set of pistons but none the less they are .030 over but they have a very nice machined look on the top of them.
so he thinks they are a step above stock but that at best.

and yes this is a daily driver , and from what i understand is that the pistons were always the weak point in these motors.

and the guy i got the car from did mention that the motor was not stock

96capricemgr

On a completely stock modern fuel injected motor at high mileage you will find exactly what you found with no wear at the top of the ring travel.

I am certain your friend is a great guy but he is showing you something completely normal and to be expected as if it is something noteworthy.
When he was trained and learning it would have been a GREAT thing but by the time of the LT1 it is just routine. Bore wear almost ended with modern port injection and thinner lower tension rings.

jrz28camaro

so from all of what you understand about my engine do you think its safe to be camming it and running it on the track? is it safe for a supercharger?

95zsean

WoW Dwayne!!! That's a bit hash on a guy you don't know.......



jrz28camaro, have a close look at the cam that came out of it to make sure it's stock. If it's not stock, put a 503 in it and have FUN......

jrz28camaro

so we did spec out the cam and it is completely stock so we are going to just drop in the cc503 and call it a day with a good tune. one other thing how much would elevation affect this cars power? I 2800ft here in boise, Idaho.

RamAir95TA

What was so harsh? The truth?

95zsean

He never asked whether he should rebuild his engine just what our thoughts where on cam selection. You know when I first started coming here it was a great help. Now not so much..... I feel sorry for the new guys that come here for help with their LT1's. I still see Fred and some of the other long time guys giving help when they can, and I'm sure their sick of answering the same question, but they would not tell someone that what they have is JUNK and only a "Select Few" know how to build a LT1........ Too bad!

96capricemgr

How would complimenting bad info help anyone?

With an LT1 at 200K miles a nice bore and crosshatch is completely normal. Such a thing at 8K miles is completely meaningless and to think otherwise just shows how outdated one's knowledge is.

The basic rebuilds I have seen with LT1s are more often than not a step backwards unless stock pistons are reused and it is just a light refresh bearings and such. It cost money to actually improve things.

The 503 cam is a all round cam, good place to start.

jrz28camaro

I don't at all dout that who ever put it together may have not done a good job or a bad job. but as for now I am sure that every thing will hold up just fine for a DD. Now I can tell you this that who ever put it back together used new part because even the the tops of the valves had almost zero signs of wear from the old stock rocker arms and the heads had bronze valve guides put in. I know this because strapped to the underneath side of the rear seat I found a machine shop recipe with a list of all the thing done. now I must say the shop that did the work is a very well respected shop up here.

and no I am not new to this whole engine scene. I am just new to v8's I came from a 1991 Mitsubishi eclipse gsx I can build engines but just like that I am trying to absorb all the info I can, bout these cars and if the only true info on here is hard nose strait to the truth no b.s. info then I will be taking any and all advice literary. so please no feel for me.

bw_hunter

Well, welcome to the world of V8's!

Since you're new, I'd recommend you research every step you take. I think you'll find out quickly enough who you can listen to without much concern. Some folks on here know so much it isn't funny. Some present their opinions as fact....
Just check everything...and in case you don't know, Injuneers and Shoebox's website are full of info that can really help you, even when you already know a lot.

One last thing, no one is going to sugar coat anything they tell you. You may not like what you hear but that doesn't make it invalid...

Enjoy!

jrz28camaro

And I dont expect any thing to be sugar coated. but still how about altitude question will me being up about 2800ft above sea level affect my power out put?