anywereiroam

Well bought my first lt1 auto camaro today. Not sure how I felt as I've always thought lt1's were junk but I thought hey don't knock on it until you try it. Car has a horrible knock so it will need a new engine if its rebuildable it will get forged internals, I know gen1 SBC, BBC, and L's platform motors and how they react to certain mods but not lt1's. So I'm not sure whether to treat it as the other two engines and do your typical ported stock heads with a valve job or just get aftermarket aluminum heads and cam I know either way I'll need a good tq converter that won't soak up much
power. I would like to have at least 400whp whether its forced induction or N/A. So if any of you lt1 guys know of good combos that can make this a fun street/track car I'm all ears! Here is a picture of it.

Catmaigne

iTrader: (6)

That looks like a catfish. Was the front end converted?

anywereiroam

Yes, its a bit hacked but nothing all time and effort can fix

bufmatmuslepants

iTrader: (3)

The bottom end you can treat like a typical 1 piece rms small block but these motors like compression due to the reverse flow cooling, you can do 12.5:1 on pump gas with the right cam. For heads, they are not the same as SBCs so don't trust any old shop to port them, use a shop that has lots of lt1 experience like AI or LE or TFS. The opti is the reason lt1s get a bad rep, but if you use a OEM or MSD opti and take it apart use loctite on all the screws it will last forever if you don't drive through big puddles.

big hammer

Lloyd Elliot top end

1-3\4 speed engineering or ebay stainless headers.

true dual system

3:73's

have a time!

HellTeeOne

Some of this has already been said, but...

These motors do indeed like compression. A typical stock bottom-end setup with ported heads and a good cam runs over 11:1, and a hot NA stroker or built motor can easily run over 12:1, all on pump fuel.

This second point cannot be stressed enough, get the heads ported and set up by someone who is extremely experienced with LT1s in particular. If us LT1 folks didn't have the likes of AI and LE, there'd be a lot fewer fast ones around. Neither of these options are cheap, but they're worth every penny and they're far better than buying aftermarket castings.

As far as the shortblock goes, the stock crank is extremely strong and if you're not building a stroker then it will be fine. The stock rod bolts are a weak point, replace them with some ARPs. The stock rods are ok to a point, but a nice set of forged H-beams won't hurt if you want to do hit it with nitrous later on. Research pistons thoroughly for both the correct quench and for the weight. The stock pistons are pretty good and lightweight so make sure that any replacements you select are at least as light. The Mahle catalog is a good place to start if you need a new set of slugs.

A well sorted and properly put together and tuned 350 or 355 LT1 can easily put down well over 400rwhp and trap over 120 mph in the quarter in a full-weight f-body.

anywereiroam

Since the lt1 does great with compression how does it do with boost?

Shownomercy

iTrader: (1)

Stock?

Very poorly.

anywereiroam

Oh no regardless the motor needs rebuilt so it will get forged internals whether I go n/a or boost. Just wondering what an ideal compression ratio/ head work would be. I live in the rockies so sometimes N/A power isn't as easily attainable

HellTeeOne

Ideal NA compression is around 12-12.5 for a built motor.

If you plan on boost, then I'd stick to 9.5 or less with quality forged flat top pistons. With the selection we have in combustion chamber sizes, there's little reason to use dished or dome pistons in most LT applications to achieve desired compression.

BSmiff

I would love to do a 355 w/12:1 compression(forged pistons and stock length forged rods) with a set of nice LE2s, a custom ground cam for nitrous and a port matched single plane intake on a single fogger in a street car. That thing would RIDE OUT.

The best thing about LT1s that no one really talks about is how strong the stock blocks are. Everyone knows the crank is stout but to this day I havent heard of anyone that has windowed a LT1 block from overpowering it. Hell Stefan is running 4.80s with his T/A stock block with a F1R and god knows how much boost. So you can save money there youre just limited on cubes. But you can spend that money on the things to make your car scream like a set of well ported heads and a custom ground cam.

The combo I listed above in a car setup for that would be a mid 5 second 1/8th mile car without question on enough spray.

anywereiroam

Oooo i built a 355 kinda like that for my third gen with a 200 shot and my god was that a blast! Should've kept it!

F0x Slaughter

400rwhp can be easily had with Heads/Cam setup from AI or LE with supporting mods.

anywereiroam

Well decided to pull the motor out today to fix it the knock and rebuild it, drove it from outside to the lift which is about 8 feet away. As soon as I get it on the lift the motor gave out.

LT1PWRD

iTrader: (2)

Daaaaamn thats one mangled rod !

F0x Slaughter

Nothing JB weld cant fix.

Catmaigne

iTrader: (6)

Lololol, how does that even happen? This can't be real.

anywereiroam

That's what I was thinking! That rod got destroyed within liken 5 seconds without revving it. I pulled the oil pan to check the cylinder wall and there is a huge crack in it. I'm just amazed since its the first motor I blew up

englundjd

thats epic rod failure!!

anywereiroam

Here is a better pic! I took disassembled the whole block and my god it was junk! All the bearings were wiped out. Broken rings, ringlands. For a moment I was considering sticking another stock lt1 and driving but after seeing that I def need to build one