hey i have a buddy that can get me a built LT4 long block... he said it should be over 400 horsepower... what do you guys know about the LT4 long blocks?? any info would be greatly appreciated... thanks...

 

has slightly better heads than the lt1, a better intake manifold, roller rockers, a slightly hotter cam, different knock sensor, etc.

Came in some firehawks and the last of the c4's.
made ~330 hp iirc.

if you put a decent cam in it, I imagine it could get to 400 fwhp w/o much trouble.

And yeah, rob is right.

 

The LT4 block itself is the same as the LT1 block. It's the same casting # in fact. What made an LT4 engine an LT4 was different heads, different intake (colored red at that) and different cam grind. Oh, also had a different knock module.

If you are looking to build up an engine why not just buy a "plain" LT1...that way you don't pay the premium price to some bozo who thinks an" LT4 block" is special.

 

I thought the LT4 blocks had 4-bolt mains?

 

so did i

 

yes... he works for a gm company and was telling me they are ordering them through some company or something like that... idk, hes going to get me some more info on what they are getting, but he said it should be rated at about 400 horsepower.. so i dont think that it is just the stock LT4 block...

 

I thought all the vette blocks had the 4 bolt, so I guess the LT4 would as well.

 

that is true
the corvette LT1s had 4 bolt mains, and the LT4s had 4 bolt mains

the LT4 heads are nice though, they flow better than the LT1s and can be ported more than LT1s. I am doing a full out LT4 conversion and then getting everything upgraded from there

 

That is true - the Corvette LT-1 blocks had 4-bolt mains. Therfore so did the LT4.

power is made in the heads and valvetrain - not the block. An lt-1 with identical heads+cam+intake etc. will make identical amounts of power to the LT4 with identical heads+cam. As mentioned above - the blocks are identical.

 

ok... i think they are coming with a different cam, and forged internals so... i'll put all the info on the engine when he gets it to me... tks guys...

 

Just make sure if it's without the intake, you need to get one. The LT1 intake won't match up to the LT4 heads. The Blocks do all wear the same casting #'s, though some have 4 bolt mains instead of 2.

 

None of this sounds right!! I thought there were NO MORE new LT4's?? There certainly aren't any intakes. So where is he getting LT4 long blocks.

 

Junkyard maybe?

 

If the engine is coming with forged internals or a hotter cam than the stock lt4 cam it isn't coming from Gm. Yes the lt4 does come with a 4 bolt main and you can get a brand new lt4 minus intake from here: http://paceperformance.com/index.asp...D&ProdID=43322

 

I figured someone would post if they were out there. I did look before posting and couldn't find any. I wonder if they have the last batch?