njansenv
njansenv Reader
4/24/10 3:45 p.m.

Well, I got the C4 running, took it to work and back. Rebuild by a local engine rebuilder.
It runs and sounds great. The car is a little....crude. Not as quick as I thought it'd be (comparing to the 240 hp M3), but torquey and responsive.

I checked the oil.

Silvery grey, no flakes, no discernible "grittiness".

I felt a little sick, but I've changed the oil and decided that it could be "break in". Am I dreaming? Oil pressure gauge goes up to nearly max when cold, and drops to about 1/4-1/2 when hot at idle. Mid range on the gauge at cruise.

I know those "numbers" suck, but it's all I have.

Thoughts?

PS: I can tag this topic Consulier and Cord, but not Corvette???

Knurled
Knurled GRM+ Memberand Reader
4/24/10 4:20 p.m.

It COULD be lazy cleaning before assembly. Machining iron throws a remarkable amount of fine dust around.

If it's quiet and maintains oil pressure, see how the oil looks after another few hundred miles.

Did you save the oil filter and cut it open and see what the element caught?

njansenv
njansenv Reader
4/24/10 4:25 p.m.

I still have the filter...I'll take it apart and check.

pres589
pres589 Reader
4/24/10 5:06 p.m.

Sounds like an excuse to start assembling something really nice on a stand to keep for when you decide it needs a change.

njansenv
njansenv Reader
4/24/10 6:08 p.m.

Careful.

My wife reads this forum.

4eyes
4eyes Reader
4/24/10 6:23 p.m.

Dude could have used silver anti-seize, as assembly lube.

daytonaer
daytonaer Reader
4/24/10 6:26 p.m.
njansenv wrote: Not as quick as I thought it'd be (comparing to the 240 hp M3), but torquey and responsive. . Thoughts?

How bout some fresh high octane? knock modules are sensitive on some of these, if you have a sensitive one some good gas will go a long way.

Rob_Mopar
Rob_Mopar Reader
4/24/10 10:03 p.m.

Not to be a doomsayer here but the coatings on the bearings can give that silvery color to the oil. Sounds like you have good pressure though. I'd keep an eye on the fresh oil after a few miles are on it.

-Rob

njansenv
njansenv Reader
4/25/10 7:40 a.m.

I'll try some fresh fuel (the stuff in the tank is old).

The "last" time I saw oil this colour, I had destroyed the rod bearings on my SRT motor. (oil starvation at a lapping day)

I'm going to watch this oil closely and see if it stays clean now. I'm still hoping it's a result of break in....

furcylndrfoury
furcylndrfoury SuperDork
4/25/10 10:40 a.m.

Stick a magnet in the old oil if you still have it. If it comes out with Iron mud on it, keep an eye on it. If not, probably anti-seize.

iceracer
iceracer Dork
4/25/10 11:34 a.m.
4eyes wrote: Dude could have used silver anti-seize, as assembly lube.

Anybody who uses ant-seize for lube, i don't want building my engine.

ansonivan
ansonivan Reader
4/25/10 11:39 a.m.

What does the local engine rebuilder have to say about the shiny oil?

Kendall_Jones
Kendall_Jones Reader
4/25/10 11:47 a.m.
iceracer wrote:
4eyes wrote: Dude could have used silver anti-seize, as assembly lube.
Anybody who uses ant-seize for lube, i don't want building my engine.

That ARP Moly lube is "kinda" silvery. But there would have to be a lot used to show up in the oil. Might be bearing surface if the engine was assembled dry with no ASSembly lube :)

KJ

Shaun
Shaun Reader
4/25/10 12:15 p.m.

Get the silver oil analyzed. Send a note describing the circumstance with the sample.

Knurled
Knurled GRM+ Memberand Reader
4/25/10 4:47 p.m.
Kendall_Jones wrote: That ARP Moly lube is "kinda" silvery. But there would have to be a lot used to show up in the oil.

I used ARP Moly lube as assembly lube exactly once, on an engine that I ran for about 200 miles before disassembly. (Coolant problem)

It did not dissolve in the oil, and there was a thick layer of black sediment in the oil pan.

motomoron
motomoron Reader
4/25/10 5:49 p.m.

Change it with fresh, cheap dino-juice. Have the old stuff analyzed.

First change out of a fresh rebuild is usually at least somewhat metallic in appearance. Hell, I raced a Yamaha FZ600 for years and it's oil was rather sparkly every change, which was typically about 4-6 operating hours. It ran, dyno-ed and inspected fine for myself and the next owner.

njansenv
njansenv Reader
5/1/10 12:02 p.m.

Well, I think I'm going to get good at engine RnR's...on the C4. Fresh oil w/160kms looks similiar. Not "as bad", but I'll try another oil change. Oil pressure (on the OEM gauge, FWIW) is now just higher than the danger mark at hot idle. It goes into the mid range at anything above idle. Slight rattle at hot startup now..... no knocks when running.
I'll change the oil, watch it, and shop for engines "in case". I'm NOT taking the motor back to the fellow for another "rebuild"...warranty or otherwise. It's not worth the hassle of installing another "tested, good motor".

I'm finding that the iron head motors are much cheaper, and may go that route. Better flow but heavier. $400 will get a good one. Tips? It sounds like an iron head, hotcam motor runs pretty well. No interest in headers/exhaust upgrades at this time.

Nathan

Travis_K
Travis_K Dork
5/1/10 7:08 p.m.

It sounds to me like the engine is done. If you have another car to drive, I would stop driving it and sell it as a rebulidable core rather than driving it until it explodes. The corvette tax on the aluminum heads may help you sell it for enough to pay for an iron head replacement. I see LT1` roadmonsters in pick and pull regularly that no one pulls parts from, while the couple LT1 camaros I have seen the engine is gone within hours. Since of course, a camaro LT! is so much better than the exact same thing in a different car. lol

Knurled
Knurled GRM+ Memberand Reader
5/2/10 9:18 a.m.

Well.... they're not the exact same thing. Iron heads, and for some reason I am thinking the pistons are different, too. The accessories and such are definitely different, stuffing a Caprice engine in a Camaro will require you to still source a bunch of parts from an LT1 Camaro.

I'm surprised that anyone would want an LT1 from a junkyard - those engines seem to blow before the bodies rust away.

daytonaer
daytonaer Reader
5/2/10 11:58 a.m.
njansenv wrote: warranty or otherwise. It's not worth the hassle of installing another "tested, good motor". I'm finding that the iron head motors are much cheaper, and may go that route. Better flow but heavier. $400 will get a good one. Tips? It sounds like an iron head, hotcam motor runs pretty well. No interest in headers/exhaust upgrades at this time. Nathan

The caprice/caddy LT1 is very similar, should have different heads (obviously) cam and exhaust manifolds. You have the shorty style header manifolds from the vette, if your switching cam's at this time its nothing to worry about. Unsure if they came with 4 bolt mains or not but I wouldn't worry about that at stock power.

In regards to the iron heads, you could A) keep them on and stick magnets to the head, B) bolt on the AL heads from your "blown" lt1, C) get some aftermarket AL heads now or down the road. In all honesty I doubt you would notice the weight penalty.

The fuel lines/intake manifold are slightly different. You could either adapt the caprice manifold and lines or run the corvette manifold and lines.

I don't see a problem with putting in a FE head LT1. I hope it works out for you, sorry to hear about your luck

pres589
pres589 Reader
5/2/10 12:14 p.m.

I like the idea of getting another 5.7 LT1 shortblock out of something else and mixing with parts that are inspected and trusted to be good from the existing Corvette LT1 currently under the hood. I'm talking about the heads, the accessories off the front, that sort of thing. Probably need to reuse the oil pan for fit in the Corvette. Mic the cam and figure out what it is, maybe it's something nice like the LT4 "HOT" cam or maybe it's the stock 1992 Corvette cam or maybe it's something else again. This is assuming it shows no signs of wear from whatever is going on in this thing currently.

Good luck, sorry you're getting burned by this thing.

njansenv
njansenv Reader
5/2/10 3:54 p.m.

I don't know that I'm getting burned. It's been frustrating, but sometimes working with older cars is like that. I certainly won't recommend the engine rebuilder to anyone, but that's not the PO's fault by any stretch of the imagination. I'm still not underwater on the car, and bought it knowing the engine needed replacing.

The long term plan will be to pull the current LT1 apart, measure everything relevant, and find out what went wrong. If it's a crank thing, then I "might" use it as a core for a stroker. Maybe.

For now, I think I'll use the C4 accessories on an iron head LT1, simply to get it going again. In the meantime, I can pull the Al heads off the car, inspect them etc.

Nathan

njansenv
njansenv Reader
5/2/10 4:04 p.m.

On a different note: anybody know anything about mounting a ZF6 to the LSx engines?

daytonaer
daytonaer Reader
5/2/10 5:44 p.m.
njansenv wrote: On a different note: anybody know anything about mounting a ZF6 to the LSx engines?

Need to fab up some type of different clutch mechanism(clutch, flywheel and throwout bearing/ with belhousing modifications/adaptors. )

A few have been done, documented on corvetteforum.

It may be easier to use a Tremec 6 speed with a c-beam adapter.

Search over on corvetteforum for lsx swap, lots of questions and threads.

http://www.zfdoc.com/projects.htm

http://forums.corvetteforum.com/c4-tech-performance/1717374-another-ls1-swap-thread-pics.html (not sure if you can see the pics)

njansenv
njansenv Reader
5/2/10 8:14 p.m.

Thanks!

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