DBL_TKE

I've always wondered what the exact differences in the blocks were. I know plenty about the LT5, I know it's a DOHC 32V engine, 3.9" x 3.66 bore/stroke, etc, but I want to know what made the LT5 engine block different and what made it similar to SBC's. Also what are the advantages/disadvantages in the block design. I can't seem to find any info related to the block design itself.

Formula350

iTrader: (3)

I emailed this guy, asking for some info, or at least just some block pics.

acsvette (add the normal link items for their site. So the mods don't have a reason to remove a link )

I also stumble across this. Alls I can say is good lord. Oh, and notice the starter location LOL I wonder how often THEY fail! Only page 4 is w/o pics, but check the flow numbers on Page 3 :O
http://forums.corvetteforum.com/show....php?t=1490283

96capricemgr

iTrader: (1)

I think the only similarity between all those other motors and the LT5 is they were available in a Vette.

Captainofiron

iTrader: (1)

wow Formula, thats pretty impressive stuff

I always dreamed of having a LT5.

Formula350

iTrader: (3)

The guy emailed back with ONE pic :\ Not very good, but it shows how weird the LT5 cylinders are. Image after the edit.

I also stumbled across a LOCAL well know, and very respected shop, DRM. Doug Rippie Motorsports. He was in Motor Trend back in the earl 90s for his Black Widow LT5s.
http://www.corvetteactioncenter.com/...lackwidow.html

Anyways, I wish there were more pics. Those LT5s are nuts. It seems like Lotus didn't stray very far from their own design on that one, or their current ones. Though, theirs are mostly smaller L with more cylinders and turbo

Captainofiron

iTrader: (1)

yea those cylinders are pretty odd, interesting looking. seems like they are floating in there only... hmm

Formula350

iTrader: (3)

yea I don't quite understand if there's ANOTHER sleeve that fits in that open area or what, because it's pretty clear we're looking at from the head deck down into the crank area.

That site I mentioned above, they make 448cid LT5s heh

the_merv

iTrader: (88)

The upper ends of the Sleeves are missing.

If I am not mistaken..that Bore/Stroke is very close to a LS1..

Formula350

iTrader: (3)

The LS1 took a few design ques from the LT5 from my reading. Like the PCV system, and it's baffle design, which creates a circulating air effect. Not 100% sure how it works, since the pictures were a bit odd, cut aways of a motor. It was an article talking about the LT5 vs the LS1 and LS6. The 90-92 motor was used though, which was the lower power rated one. Not the updated one. But that year was pretty much dead even with the LS6. The LS6 only got a few more ponies around the 5K mark, but they tied around 6K.

aboatguy

The merv is right the sleeves are missing.

My machinist (Brian Ebert) builds big bore, stroker LT5s. I watched him making his own sleeves one day. The blocks are totally different than the SBC and due to the low numbers built there is no volume discount when it comes to speed parts. So you have to PAY to play in the LT5 league especiallly in the 400+ CI club.

I love the way LT5s look and sound incredible at speed. But I'll probably buy a C5 ZO6 or a plane jane C6 becuase if I bought a ZR1 I'd have to mod it and they can swallow 10K quicker than Jenna Jameson on a tube steak whereas LSX mods are notsomuch.

If I remember to bring my camara the next time I'm there I'll see if Brian will let me snap some pics of some of the LT5s in the shop.


Mike

DBL_TKE

Well after much research and reading just about every website that has the LT5 in it I also found a website of an engine builder who owns his own company but gave some detailed photo's of disassembling the engine and taking notes of key features.

http://www.bustedcar.com/silverfox.htm

-The block is a two piece design...The main caps are incorporated into an intermediate girdle assembly.

-center oiled crank. oil pump driven by the front of the crank and oil is sent to the crank FIRST, then to the passages in the block.

-cup plugs in the crank centerline.

-The ignition control module and coils are located under the intake plenum.

-Oil pan has a built in windage tray.

-Oil pump pulls oil from the pan through an o-ringed port.

-The starter is also located under the intake.

-The throttle body has a very small third butterfly valve that opens first, then the main throttle blades open.

I can also see that the water jackets differ vastly from an LS1 block to the SBC to the LT5...

Formula350

iTrader: (3)

Yea, you can clearly see that 2-piece stick out where the orange RTV is. That's interesting. That riced out neon blowing the pistons up is good humor.

DBL_TKE

So do I and Formula350 really know more about LT5's than anybody else on this site??

the_merv

iTrader: (88)

You got me beat..I know enough to know what they are and how they work..nothing too technical though..

91Z28

409cfm @ .450" lift......amazing, and on 427 CID to boot.

That_guy

iTrader: (1)

lol i know they were made to intentionally beat ferraris and such. lol like the c6 z06. but yea u and formual got this covered.

Mortify

Ugh the thread has closed ont he 427 LT5... I want dynos!!!