1uz non vvti Block differences between Series 1 and series 2

Summary

In this video, Calvin from the Catching Company in New Zealand, along with Jason, discusses the differences between Toyota's Gen 1 and Gen 2 engine blocks, specifically focusing on the 1UZ-FE engine. They highlight the changes in block casting, including the introduction of holes in the Gen 2 block for weight reduction and potential harmonic improvements. The discussion also touches on the transition from thick to thin connecting rods and the lighter pistons and crankshaft in Gen 2 engines. The hosts compare various engine components, noting similarities and differences, and speculate on the reasons behind Toyota's design choices without definitive answers, inviting viewer input and further exploration.

Takeaways

• 🔧 The main difference between a Gen 2 and a Gen 1 block is the presence of additional holes in the Gen 2 block, which makes it lighter.
• 📅 The transition from Gen 1 to Gen 2 blocks occurred around the 9th month of 1994, with the changes appearing in the USA market in 1995.
• 🏎️ The Gen 2 block was introduced alongside lighter connecting rods and pistons, enhancing engine performance.
• 🔩 The change from Gen 1 to Gen 2 is marked by the switch from thick to thin connecting rods, which is also seen in the LS400s and SC400s models.
• 🏭 The block casting for both Gen 1 and Gen 2 is believed to be the same, with modifications made for specific engine components.
• 🔧 The Gen 3 or VVT-i blocks further lightened the crankshaft by 1.5 kg and modified the oil galleries.
• 🧐 The additional holes in the Gen 2 block are speculated to be for block harmonics or windage pressure, although this is not confirmed.
• 🔍 The script suggests that the Gen 2 block is preferred by some dirt track Speedway racers due to its design.
• 📏 The block's underside has distinguishing features, such as the presence of holes, which are not found in the Gen 1 block.
• ⚙️ The script highlights the importance of matching bearing sizes when rebuilding engines, as indicated by markings on the blocks.

Q & A

What is the main difference between a Gen 1 and Gen 2 engine block in Toyota's 1UZ series?

The main difference is the presence of additional holes in the Gen 2 block, which makes it lighter.

Why did Toyota introduce changes in the engine block design from Gen 1 to Gen 2?

Toyota made changes to improve the engine's performance, specifically by introducing lighter rods and pistons.

In which year did the change from Gen 1 to Gen 2 engine blocks occur in the USA market?

The change occurred in the USA market in 1995, registered as 95 year models.

What is the significance of the additional holes in the Gen 2 engine block?

The additional holes are believed to be for either weight reduction or to change the harmonics of the block.

Is there a difference in the oiling and water holes between Gen 1 and Gen 2 engine blocks?

No, the oiling and water holes in the top of the engine blocks appear to be the same between Gen 1 and Gen 2.

What are the differences in the main cap design between Gen 1 and Gen 2 engine blocks?

The Gen 2 has chamfering and no recess, while the Gen 1 has a flat edge with recesses.

What is the purpose of the numbers found on the engine blocks?

The numbers indicate the bearing sizes fitted at the factory, which can vary and are not necessarily the same across all engine blocks.

Why might some engine blocks have different numbers indicating bearing sizes?

The different numbers could be due to mass production machining differences, where the factory adjusts the bearing sizes to meet specific tolerances.

Are there any differences in the block casting between the VVT-i and non-VVT-i versions of the 1UZ engine?

The VVT-i block casting is almost the same as the non-VVT-i, but it has modifications for the oil galleries.

What is the significance of the bolt-on drain in the engine blocks?

The bolt-on drain is an additional feature compared to the Gen 1 block and is part of the block's design for oil management.

Outlines

00:00

🔧 Differences Between Gen 1 and Gen 2 Toyota Blocks

The first paragraph discusses the differences between Toyota engine blocks, specifically the Gen 1 and Gen 2. The speaker, Calvin from a New Zealand catching company, explains that the Gen 2 block has additional holes, making it lighter. These changes were introduced in the LS400s and CLC models around September 1994, with the Gen 2 featuring thinner rods and pistons. The block castings for Gen 1 and Gen 2 are largely the same, with the main difference being the presence of holes in the Gen 2 block. The discussion also touches on the sequential ECU and the transition from Gen 1 to Gen 2 in terms of engine components like rods and crankshafts.

05:00

🏋️‍♂️ Detailed Comparison of Engine Block Castings

In the second paragraph, the focus is on a detailed comparison of the engine block castings. It is noted that the top of the blocks, including the oiling and water holes, are similar between Gen 1 and Gen 2. However, the underside of the blocks reveals the presence of additional holes in the Gen 2 block, which may be related to windage pressure or block harmonics. The speaker speculates that these changes could be due to a desire for lighter components or to adjust the harmonics of the engine block. The discussion also includes observations on the main cap design differences and the presence of matching holes that are not part of the casting itself.

10:03

🔩 Engine Block Markings and Bearing Specifications

The third paragraph delves into the markings found on the engine blocks, which are related to the bearings fitted at the factory. These markings indicate different bearing sizes, which can vary from block to block. The speaker mentions that these markings can be confusing for those who are not familiar with them, but they are essential for ensuring the correct bearings are used during engine assembly. The conversation also touches on the importance of using genuine parts and the potential issues that can arise from using aftermarket bearings with different specifications. The paragraph concludes with a note on the practicality of identifying block differences and the value of such knowledge.

Keywords

💡Gene One Block

The 'Gene One Block' refers to the first generation engine block design discussed in the video. It is characterized by a specific set of features, including a particular design of holes and a main cap. The video compares this block to the 'Gene Two Block' to highlight the differences in design and functionality. For instance, the script mentions that the Gene One Block lacks the extra holes present in the Gene Two Block, which is a key distinguishing feature.

💡Gene Two Block

The 'Gene Two Block' is the second generation engine block design that the video compares to the Gene One Block. It is noted for having additional holes that are not present in the Gene One Block, which suggests a change in the design for potentially improved performance or weight reduction. The video discusses how these changes might have been made to improve the engine's performance or reduce weight, as indicated by the script's mention of a 'lighter block'.

💡Block Casting

Block casting refers to the process of manufacturing engine blocks through casting methods. The video discusses differences between the castings of Gene One and Gene Two blocks, suggesting that while there are modifications, they may have originated from the same casting process. The script points out that the main difference lies in the presence of extra holes in the Gene Two Block, which could be a result of casting modifications.

💡Camshaft

The camshaft is a part of the engine that controls the opening and closing of the engine's valves. In the context of the video, the speaker mentions moving to the camshaft to discuss the differences between the Gene One and Gene Two blocks. This suggests that the camshaft's position or design might be influenced by the block's design, which is a critical aspect of engine performance.

💡Crankshaft

The crankshaft is a major component of the engine that translates the reciprocating motion of the pistons into rotational motion. The video script mentions that the crankshaft in Gene Two engines is almost identical to that in Gene One engines, with the only difference being the part numbers. This implies that the crankshaft's design has not significantly changed between the two generations, which is important for maintaining engine balance and performance.

💡VVT-i

VVT-i stands for Variable Valve Timing with intelligence, a technology used in Toyota engines to improve performance and efficiency. The video discusses how the VVT-i system's implementation might have influenced the engine block design, particularly in the Gene Three blocks where the block casting was modified for the oil galleries to accommodate the VVT-i system. This highlights the interplay between engine technology and physical engine design.

💡Main Bearings

Main bearings are components that support the crankshaft within the engine block. The video script mentions that there are differences in the main bearings between certain engine blocks, indicated by the numbers stamped on the blocks. These differences in bearing sizes are crucial for ensuring proper engine operation and can affect the engine's performance and longevity.

💡Bore Thickness

Bore thickness refers to the thickness of the engine block's cylinder walls. The video script alludes to a future video discussing bore thickness and material differences, suggesting that these factors are important for engine durability and performance. Thicker bores can handle higher cylinder pressures, which is particularly relevant for high-performance or modified engines.

💡Oil Galleries

Oil galleries are channels within the engine block that distribute oil to various engine components. The video discusses modifications to the oil galleries in the Gene Two and VVT-i blocks, indicating that these changes were made to improve oil distribution and engine lubrication. Proper oiling is critical for reducing friction and wear within the engine.

💡Windage

Windage refers to the resistance created by the movement of air within the engine's crankcase. The video speculates that the extra holes in the Gene Two block might be related to windage reduction, which could improve engine efficiency by reducing the power lost to air resistance. This highlights the video's focus on the subtle design changes that can have significant impacts on engine performance.

Highlights

Difference between gene two and gene one block is the set of holes

Gene two block has extra holes, making it lighter

Main cap design differs between gene one and gene two

Toyota released an upgraded block in 1994 for the USA market in 1995

Upgraded block has lighter rods and pistons for better performance

Change from thick to thin rods occurred in 1994 for LS400s and CLCs

Sequential ECU introduced with wider body for SC 400s

Gen 1 and Gen 2 engines have almost identical crankshafts

Gen 3 engines have a lighter crankshaft by 1.5 kilos

VVT-i engines have modified block casting for oil galleries

Gen 1 and Gen 2 blocks likely came from the same casting

Discussion on Facebook about block casting differences

Gen 1 block has corrosion and pitting, deemed scrap

Gen 2 block stripped from an engine for comparison

No difference in oiling and water holes between Gen 1 and Gen 2

Ribbing and block mounting points are the same in both generations

Difference in holes underneath the block between Gen 1 and Gen 2

Cap design differences noted between Gen 1 and Gen 2

Extra holes in Gen 2 block possibly for block harmonics

1UZ VVT-i block also has the same holes as Gen 2

Discussion on why extra holes were added in Gen 2 blocks

Bolt-on oil gallery knock senses are a feature of Gen 2 blocks

Numbers on blocks related to bearing sizes at the factory

Importance of matching bearing sizes when replacing

Useless information provided for educational purposes

Transcripts

the difference between a gene two

and a gene one block

is these set of holes here

so there

that means change extra holes in it

we'll also see the main cap see the

design of the main kit though that isn't

part of the block casting is it this is

casting so that that is our difference

there

but you'll see here the the design here

we've got

Reese's

no recess in a different shape so that's

the quick version of Gene one block Gene

two block

s through the box

good question isn't it what is it for

well I'm going over to camshaft on the

bottom

yeah

get it guys it's Calvin

from the catching company in New Zealand

oh and Jason and Jason too both of us

and we were just we were fortunate

enough to have lots of bits lying around

and so sit them next to each other so we

can compare and share some of the

knowledge which is kind of disappearing

on this older stuff Toyota at some point

would have done a release and said hey

the block on the one you zdfe and the

1994 relief production year

released in the USA in 1995 it had this

upgrade at the block has been changed to

improve something

and it's because they put some holes in

it or it's a lighter block

which it is a lighter block because it's

got some holes in it

so to Define

series one and series two or gen 1 and

Gen 2 use it

it's the change between the thick rods

and the thin rods

and this happened in the ls400s and the

CLC is around about uh it was the ninth

month of 1994 to be exact but in the USA

you'll see it in uh

registered 95 so 95 year 95s model year

also happened in the soras SC 400s when

they went to the sequential ECU which is

the wider body ECU

then the crowns the 131 and the 141 were

gen 1 and the 151 non-vtiser Gene 2.

and so not only did Toyota that's when

Toyota put the

lighter rods and the lighter pistons in

which Reeve better in an inner form

so that's what we mean when we go Gene

two engines got the one with the load of

rods and motorists crankshaft

pretty much identical it's probably

easier just to say they are the same

crank

um they are different part numbers

but it's very hard to tell the

difference between the two

it is the gene threes or the vvtis where

they lighten the crank by one and a half

kilos but we're focusing on the block

casting

the vvti's block casting is is almost

the same but of course they've modified

it for the oil galleries for the vvti

threeuz they put a bigger hole in it but

all this the same casting and the Gen

one and gen 2 blocks

I believe came from the same casting

so

I actually asked on a Facebook post and

if there was a difference

and some guys were brave enough to

actually say no there's no difference

even though they're wrong that's a

pretty brave move

uh but

the a lot of guys were guessing and I

had some pictures

um and I asked specifically on the block

casting not into the VVT ice but

specifically on the block casting

between a gene one and a gene 2.

[Music]

this is a gen one

it does look like it's been under the

sea because I would almost say that

these corroded just about through the

oil gallery knock senses are a bolt on

and we haven't removed them because this

block is scrap that's going to rubbish

it's got massive pitting in the walls

this is 100 a Gen 2 block stripped from

a Gen 2 engine

[Music]

some people suggested there was a

difference in

the holes in the top

you know I can see no difference between

the oiling and the water holes in the

top

between the two engines I can't see any

shapes of the saw the same

I believe the bores the sleeves are the

same

in here all the ribbing is the same all

the same block mounting points exist

certainly on the front

everything is the same there as well and

all accessories bolt on

down the sides

they are the same though have you seen

the ones that don't have the holes

so these holes here

foreign

and are used on the crown the 131 Crown

to mount

uh the oilfield housing

some blocks don't have that tapped so

that could actually be seen as a

difference but it's not between Gene one

and Gene 2.

it's specific to some

some models that seem to randomly not

have them tapped

other side

I was in such a hurry today I didn't

even managed to get my workflix on

we just uh try not to smash the torch

same thing here

same thing along here

they're all the same so the difference

comes in The Underneath

rolly Rolly Polly but this is a gene one

this is the gene one

you go back here

and there is no hole board in that

location there

no wrong

it's there oh sorry is it look oh yes

okay yeah

yes it's there sorry that location there

that's where the holes board and it

continues

on the Gen 2

through single one two three four five

so it goes through number five

through number four number three

but not number two

so I was thinking possibly for windage

pressure

between

um

the compartments of the engine but it

doesn't make sense not to put it through

the front one

if we look at the cap design we do see a

difference

we've got some chamfering

and we've got

no recess it's flat on the edges in here

we still have the place for some oil to

get into the thrust washers

whereas these ones are square

and

got some recesses

and a big recess in here still the same

oil ports for the thrust washer or

places where all can get in

but it comes down to these these holes

is the main one and of course this isn't

part of the casting it's just

interesting to note because they are

matched with the block

and I haven't compared if it changed

part way through the teens but I suspect

that's a 20 only

and we have the hole there there and

there

I actually think

um

it's it's to do with either they were

going for lighter so they found

somewhere but I actually think it was to

do with block harmonics

this is my guess

something to do with the different

reciprocating Mass change the harmonics

of the block slightly and that's how

they solve the problem

possibility

correct I need to find a Toyota engineer

who worked on these and can tell us why

on the gentose

they made those couple of changes

and interesting enough guys we do have a

1uz vvti block here

and it does have those same holes I

can't tell you on the 3z we didn't check

all right if I checked I didn't remember

um hey I'd love to hear some thoughts on

what you guys think of why they put

those extra holes in if anyone's got any

documentation I would love to see that

we're actually working on a video too on

the

the bore thickness and the material

between the cylinders on a 3z

and this one actually fits in really

nicely with that

um

we could always say that the drain

is different too but it's a bolt-on

oh

it has a bolt on it's an extra compared

to the gene one

it's definitely that whole

the reason I found out about this

actually is is because the stock carbo

is the dirt track Speedway guys

some of them

seek that Gen 2 block

and

that is where this one is distant it's

got some Rust marks but it's going to be

bored and probably make about 500

horsepower in a when it's finished

few other interesting things to note on

these blocks too is a series of numbers

and this is to do with the bearings

has to do with the big end bearings that

are fitted

and I believe these ones are to do with

the main bearings that are fitted so

they they aren't someone afterwards that

is actually done at the factory that's

scribbling on the Block

oh see this has got a 2223

and this is where we've got a two two

two

so it's got a a three bearing size three

on the back

upper is that the that's the upper a

that's the lowest that's the upper so

it's got one bearing size different

on that one

um

so quite a different set of bearings

I think you'll find most titles

we have that stamp on the walls yeah

yeah

um it kind of freaks people out a little

bit or they question it when they get a

block and they pull it apart they think

it's a virgin

and there's some numbers on it like that

they're like What's what is it what are

these numbers yeah

of course we work on lots of Toyotas so

we we're quite used to it just like yeah

and then you get a set of aftermarket

bearings and you put them the same size

everywhere

which can get you out which can catch

you out yeah did your engine have

you mix it all up your bearings and it

was all the same or not

uh this this might have got a new cranks

are not everything was all good I just

like it was machinists cool

yeah

but yeah it's got all sounds like rooms

in it yeah and of course that was just

to allow for Machining

Mass Production Machining differences so

they must have had someone at the

factory actually measuring

bearing clearances and going no that

one's not quite right

you can't just go to toilet you've got

to buy if you're buying genuines yeah

buying genuines you want to buy say if

you have a block and it was like two

four three two you're gonna buy Six

appearance

yep

I think it's quite expensive quite

quickly yes

so I hope that's been helpful a bit of

useless information

but if you had to tell the blocks apart

it is possible to do that talk to you

soon catch you later