Question on LT1 motors?

[56ClassicTruck]

I was just hoping to ask what is a LT1 motor?? I see they are thought after but why what is the difference from just a 350 4 bolt? I no on one of my post I said I have a 1993 Buick Road-master 5.7 motor and some one post back to bad it was not a 1994 Roadmaster cus they have a LT1 motor? Dose any one no if a 1995 Roadmaster wagon have the LT1??

[63 & 64 Bowties]

I'm probably not the right person to answer these questions. But, in the Caprice cop cars, 94 was the first year for LT1 (I've owned a 93 and a 94.) So, I'm assuming the Buicks were the same. 92 and older was a TPI. Someone correct me here if I'm wrong.

[Atomsplitter]

The 1995 Roadmaster has the same engine that I'm using but mine is out of a 1995 Impala SS and yes they are LT1's. I have a picture of mine in my album.

[blackdiesel]

Originally Posted by 56ClassicTruck

I was just hoping to ask what is a LT1 motor?? I see they are thought after but why what is the difference from just a 350 4 bolt? I no on one of my post I said I have a 1993 Buick Road-master 5.7 motor and some one post back to bad it was not a 1994 Roadmaster cus they have a LT1 motor? Dose any one no if a 1995 Roadmaster wagon have the LT1??

i have a 97 vette motor in my 38 coupe and i really like it. if i had it to do over again i probably would have went with a vortech motor 5.3 or a 6.0 out of a late model chevy/gmc pickup. much more reliable and cheap hp.

when you ask whats the difference between a carbed 350 and an lt1 i assume you mean besides the obvious? such as fuel delivery for instance. not to mention the distributer located below the water pump. if you do decide to go the lt1 route make sure to get a later model motor, it will have the upgraded opti spark (vent hole) which will help in the notorious distributer failure

[56ClassicTruck]

Originally Posted by 63 & 64 Bowties

I'm probably not the right person to answer these questions. But, in the Caprice cop cars, 94 was the first year for LT1 (I've owned a 93 and a 94.) So, I'm assuming the Buicks were the same. 92 and older was a TPI. Someone correct me here if I'm wrong.

thanks for the info guys....... today I was told that my 93 buick roadmaster limited has the LT1 motor?? dose any one no for sure??? how can i fine out......

[63 & 64 Bowties]

Originally Posted by 56ClassicTruck

thanks for the info guys....... today I was told that my 93 buick roadmaster limited has the LT1 motor?? dose any one no for sure??? how can i fine out......

Look under the air cleaner. If you see what looks like an intake manifold and sorta looks like a carb, you have a Throttle body 350 which is still an excellent donor for your truck.

[blackdiesel]

If you have a distributer in the back you don't have a LT1. If the spark plug wires go under the water pump, then you do have one.

[blackdiesel]

here ya go, this is what an lt1 looks like. of course mine has the top and rail covers and dirty valve covers. but you get the idea

[56ClassicTruck]

Cool thanks guys!!!!! Man I love this site!!!! well got to go out and look...

[Jonboy]

Another easy way to tell is that on the B body (Roadmaster, Caprice/Impala SS, Fleetwood) cars, the LT1 cars have dual exhaust. There is a 4.3 V8 (L99 I think) that looks identical, but is pretty much useless for performance. The B body LT1's are similar to the F (Camaro/Firebird) and Y (Corvette) engines, with the exception of the heads. B car engines are rated at 260 HP, and have iron heads. The F car engine is rated at 275 HP, and the Y car is 300. The only differences in the F & Y engines are the intake and exhaust packaging (and accessory drives), with the F car being a lot tighter to fit in the space.

[Atomsplitter]

Here's a bit of information on the changes in the 5.7 from 1993 to 1994.
--------------------------------------------------------------------
Year-to-year changes
1992: A 4-door sedan joined the Roadmaster wagon as an early 1992 model, carrying the 5.7 L TBI (Throttle-Body Injection) V8 engine that developed 180 hp. That engine also went into the Estate Wagon, replacing the 5.0 L.
1993: Window lockout feature and the addition of a new spoke wheel cover mid-year.
1994: A redesigned dashboard included a new instrument cluster, with climate controls mounted higher and a knee bolster below. Dual airbags were also installed. The 5.7L TBI is replaced with a detuned 5.7L LT1 engine from the Chevrolet Corvette. This LT1 had cast iron cylinder heads and produced 260 hp (194 kW) (40 less horsepower than the Corvette). A new electronically-controlled 4L60-E 4-speed automatic transmission replaces the 4L60.
---------------------------

[56ClassicTruck]

Originally Posted by Atomsplitter

Here's a bit of information on the changes in the 5.7 from 1993 to 1994.
--------------------------------------------------------------------
Year-to-year changes
1992: A 4-door sedan joined the Roadmaster wagon as an early 1992 model, carrying the 5.7 L TBI (Throttle-Body Injection) V8 engine that developed 180 hp. That engine also went into the Estate Wagon, replacing the 5.0 L.
1993: Window lockout feature and the addition of a new spoke wheel cover mid-year.
1994: A redesigned dashboard included a new instrument cluster, with climate controls mounted higher and a knee bolster below. Dual airbags were also installed. The 5.7L TBI is replaced with a detuned 5.7L LT1 engine from the Chevrolet Corvette. This LT1 had cast iron cylinder heads and produced 260 hp (194 kW) (40 less horsepower than the Corvette). A new electronically-controlled 4L60-E 4-speed automatic transmission replaces the 4L60.
---------------------------

do you have any info on 1995 buick roadmaster vin 1G4BN52P8SR415952?

[cajundragger]

as per wikipedia..

"General Motors' Generation II LT is a small block V8 engine. Making its debut in the 1992 Chevrolet Corvette, the new LT sought to draw upon the heritage of the ultimate small-block, the 1970 Chevrolet LT-1.
A significant improvement over the original Generation I V8 is the Generation II LT's "reverse cooling" system, allowing coolant to start at the heads and flow down through the block. This keeps the heads cooler, affording greater power through a higher compression ratio and greater spark advance at the same time it maintains higher and more consistent cylinder temperatures.
Some parts from the Generation II are interchangeable with the old Generation I engine. The interchangeable parts include the rotating assembly (crank shaft, pistons, and connecting rods) of the Generation I small block with the one-piece rear main seal. The LT uses a new engine block, cylinder head, timing cover, water pump, intake manifold, accessory brackets, and front-mounted "Optispark" distributor. Engine mounts and bell housing bolt pattern remain the same, permitting a newer engine to be readily swapped into an older vehicle."

"In 1992, GM created a new-generation small-block engine called the LT1, similar to the high-output Generation I LT-1 of the 1970s. It displaced 5.7 L (350 cu in) and was a 2-valve pushrod design. The LT1 used a reverse-flow cooling system which cooled the cylinder heads first, maintaining lower cylinder temperatures and allowing the engine to run at a higher compression than its immediate predecessors.
This engine was used in:
Y-body:
1992-1996 Chevrolet Corvette C4
F-body:
1993-1997 Chevrolet Camaro Z28 and SS
1993-1997 Pontiac Firebird Formula and Trans Am
B-body:
1994-1996 Buick Roadmaster
1994-1996 Chevrolet Caprice
1994-1996 Chevrolet Caprice Police Package
1994-1996 Chevrolet Impala SS
1994-1996 Chevrolet Caprice Wagon
1994-1996 Buick Roadmaster Wagon
D-body:
1994-1996 Cadillac Fleetwood
"

[56ClassicTruck]

Originally Posted by cajundragger

as per wikipedia..

"General Motors' Generation II LT is a small block V8 engine. Making its debut in the 1992 Chevrolet Corvette, the new LT sought to draw upon the heritage of the ultimate small-block, the 1970 Chevrolet LT-1.
A significant improvement over the original Generation I V8 is the Generation II LT's "reverse cooling" system, allowing coolant to start at the heads and flow down through the block. This keeps the heads cooler, affording greater power through a higher compression ratio and greater spark advance at the same time it maintains higher and more consistent cylinder temperatures.
Some parts from the Generation II are interchangeable with the old Generation I engine. The interchangeable parts include the rotating assembly (crank shaft, pistons, and connecting rods) of the Generation I small block with the one-piece rear main seal. The LT uses a new engine block, cylinder head, timing cover, water pump, intake manifold, accessory brackets, and front-mounted "Optispark" distributor. Engine mounts and bell housing bolt pattern remain the same, permitting a newer engine to be readily swapped into an older vehicle."

"In 1992, GM created a new-generation small-block engine called the LT1, similar to the high-output Generation I LT-1 of the 1970s. It displaced 5.7 L (350 cu in) and was a 2-valve pushrod design. The LT1 used a reverse-flow cooling system which cooled the cylinder heads first, maintaining lower cylinder temperatures and allowing the engine to run at a higher compression than its immediate predecessors.
This engine was used in:
Y-body:
1992-1996 Chevrolet Corvette C4
F-body:
1993-1997 Chevrolet Camaro Z28 and SS
1993-1997 Pontiac Firebird Formula and Trans Am
B-body:
1994-1996 Buick Roadmaster
1994-1996 Chevrolet Caprice
1994-1996 Chevrolet Caprice Police Package
1994-1996 Chevrolet Impala SS
1994-1996 Chevrolet Caprice Wagon
1994-1996 Buick Roadmaster Wagon
D-body:
1994-1996 Cadillac Fleetwood
"

WOW!!!! Thank you grate info!!!!!

[56ClassicTruck]

Well I just bout a 1994 Buick Roadmaster limited today as a donor for my 56 truck project for $750 and it runs grate...... hoping to use complete LT1 drive train posi rear and wire harness and AC, seats..

[63chevyll]

do you have a picture?

[1952ssr]

Originally Posted by 56ClassicTruck

Well I just bout a 1994 Buick Roadmaster limited today as a donor for my 56 truck project for $750 and it runs grate...... hoping to use complete LT1 drive train posi rear and wire harness and AC, seats..

Sounds like a good plan, my '52 has a LT1 / 4L60 & fuel tank from a '94 Z28, Cadillac fuel lines, and a roadmaster drive shaft.

[56ClassicTruck]

Originally Posted by 1952ssr

Sounds like a good plan, my '52 has a LT1 / 4L60 & fuel tank from a '94 Z28, Cadillac fuel lines, and a roadmaster drive shaft.

hey 1952ssr, would like to see some of your work on that.

[1952ssr]

Originally Posted by 56ClassicTruck

hey 1952ssr, would like to see some of your work on that.

I'll snap some for you this weekend, my headers and exhaust should be delivered today. I'll put them on and then take some pictures. What exactly would you like to see, none of the body is on it so I can get you some really good shots.

[bensimmons_05]

I would put a new gasket set on the engine.

The LT1's have a tendency to leak oil, especially from the intake.

The LT1 in my Trans am leaks from every possible location!!

They are good motors though and parts are plentiful.

Just watch out for water getting even close to the distributor.

Oddly enough the weep hole for the water pump is DIRECTLY above the distributor, and it is a common thing for the water pump to start crying so if you get a donor motor I would definitely replace with a new water pump.

[Atomsplitter]

When I put the '95 LT1 into my truck I was told NOT to use Synthetic oil as it causes these particular motors to leak (something about the molecules being smaller than in regular oil). Makes no sense to me but this was a suggestion from a guy that has 4 cars with the LT1.

*** Also DO NOT REMOVE THE 3/8" STEEL LINE FROM THE REAR PASSENGER SIDE OF THE MOTOR. It's there to help relieve some of the heat built up in the backside of the motor by sending hot coolant directly from this area back to the radiator. If you eliminate it you will probably have an intake manifold leak in the future. You'll also notice it passes throught the intake. This is for heating up the throttle body in the winter. You can bypass the throttle body if you only run this motor in warm weather or warm parts of the country (you pickup 5HP if I remember correctly).

If anyone needs a Water Pump, Optispark, etc. you may want to contact these guys http://www.rmsautoparts.com/ as they've taken over Dal Slabaugh's parts business. No one could touch his prices and fast service (his parts were about 1/3rd of what I would have paid in Canada and they were in GM/Delco boxes not from J.A.Pan Ltd). I don't know anyone that has used this source but it may be worth your time.

[56ClassicTruck]

Thanks guys for heads up. I didn,t know this about the LT1..

[Jonboy]

Originally Posted by blackdiesel

here ya go, this is what an lt1 looks like. of course mine has the top and rail covers and dirty valve covers. but you get the idea

Hey blackdiesel, what accessory setup is that? I have a similar one that came on my truck, and the idler pulleys squeak like crazy. Wondering where to source replacements from.

Another pecularity on these engines is that they seem prone to eat EGR valves. I have had to replace them on all of my B-bodies. I think it will just go away on my truck, though.

[blackdiesel]

Alan groves is the brackit maker that I used. and no EGR valve being used here.

[1952ssr]

Here's some pictures for 56CT. I don't have any new ones with my headers on.