The subject basically is my question. I've never really owned anything other thean a 327 or 350 so I was trying to keep up.

350's are cast iron and most settup for flat tappet cams from the factory (85 or 86' and up are for roller cam) while LT1's and LS1's are all aluminum (heads, block, ect) and set up for roller cams and EFI (electronic fuel injection).
These are the main differences, there are alot more differences in the blocks themselves.

They are completely different engines.

GM made about five of them.

The first was the old 1955, 265 without an oil filter on it, a rope seal and no block cast in place cam groove.

The second was the standard engine with an oil filter boss, but the early model had a rope for a rear seal. I don't remember when they added the cast in place cam groove.

The third was the standard modern engine with the rubber rear seal, oil filter boss and cast in place cam groove.

The forth was the one that was like the third engine but had a shaft waterpump drive. I think it is reverse cooling, too boot!

And the fifth is the LS1 that is all different except for bore spacing!

And please tell me if I missed one. pdq67

an LT1 is a 350 with a different cooling setup that drives the water pump off the cam gear without a seperate external belt, and runs the water thru the heads before the block- thus in theory allowing a higher compression ratio and more aggressive ignition timing. the distributor is mounted on the front of the engine behind the water pump. Corvette and Camaro/Firebird versions had an iron block and aluminum heads, and the big car(Caprice, Roadmaster) version had cast iron heads that allegedly flow better than the aluminum versions.
the LS1 is a totally different design that made it's debut in the all new 97 Vette. it has an aluminum block and heads with a plastic intake manifold. the only parts that interchange with an older small block- so i hear- are the roller lifters. it has no distributor, with a seperate coil for each spark plug. GM went back to "normal" coolant flow on the LS1- block first, then heads-, and the water pump has a belt again.
and they just look badass...

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1971 Nova(looks like 69 camaro from underneath!)
355sb, vortec heads, HOT cam,T-10 tranny, 3.70 gears 16X8" IROC wheels. 12" Corvette brakes on the way.
see pics here http://community.webshots.com/user/novaderrik

PLASTIC INTAKE?!!

I've gotta see one of those.



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68 Coupe, 350 4-speed
Jim's Camaro Corner

i rattle off all the other stuff i know about an LS1, and you focus on the plastic intake? they (plastic engine parts)are getting to be pretty common, actually. the mighty 5.7 liter vortecs in the 96 and newer trucks also had a plastic intake, an i'm pretty sure a bunch more engines also do. i'm pretty sure the new 8 liter- or whatever- big block in the newe trucks also has a plastic intake, but not sure on that.
i read somewhere a while back that some crazy engineers somewhere- maybe europe- are working on plastic engine blocks and heads... think how light that wpould be...

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1971 Nova(looks like 69 camaro from underneath!)
355sb, vortec heads, HOT cam,T-10 tranny, 3.70 gears 16X8" IROC wheels. 12" Corvette brakes on the way.
see pics here http://community.webshots.com/user/novaderrik

So it sounds like ther're all basically 350 blocks with different cams, heads, belts, pumps and fuel system. Until we get to the LS1 which is totally new. Is this correct.

BTW where does the aluminum bocks fit into the picture.

Plastic intakes are really cool until you have a nasty backfire and crack the bugger and need a new one, then they are not so cool.

Check out "Polymotor"(???) if you want info on the plastic engine novaderrik
mentioned.

I think it is supposed to be carbon fiber reinforced epoxy and ceramic or something like that and if not mistaken, waterless and oiless. Has a carbon fiber crank in it, plus rods...

Hope I got this right, it's been a long time since I looked into it.

I even think they tried running it at Indy one year but didn't make the time trials. pdq67

I helped a friend on a fairly late model 4.6 Cougar once and it had a plastic intake that broke, and when he got it worked on by the FO** garage, they were replacing all of the broken ones that came in with aluminum ones.

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Joel
1969 Z28
LeMans Blue-White Stripes
#'s matching, P-O-P

CamaroNOTCamero- LT1's aren't aluminum blocks...some of them aren't even aluminum headed motors. Alot of the vette LT1's were aluminum head motors but the ones in some of the camaro's, firebirds and the 94-96 impala's were iron headed.
Donnie

Actually the Camaro and Firebird LT1's also had aluminum heads. The Impala SS's had the iron heads.

Jody

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MY CAMARO

I heard the LS1 has 6 bolt mains.. Four in the top and one on each side. cool if true

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73 Camaro, 350 .030" over, and 450 HP

They do. kinda main like a "side-oiler" 427 Ford with cross bolted mains and the deep skirted block. I think the pan is even a load bearing member, too. pdq67

Jody,
Thanks bro. I couldn't remember if back when they first put the LT1's in the F-bodies if they had iron or aluminum.
Donnie