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[ZaneKaminski]

Hi all. I own a Cadillac Catera (badge-engineered Omega B) and my X30XE motor recently blew up on me. A friend and I plan to install a new engine, and I would prefer to install the slightly newer, larger Y32SE. The Catera is like 400 pounds heavier than to the Omega B and Cadillac for some reason decided to detune the 3.0 V6 by like 10 horsepower compared to in the Omega B... So the extra power and torque would be appreciated.

Anyway, I'm wondering about the specific differences between the 3.0 and the 3.2. Obviously the 3.2 has been stroked out more, and it has the variable-length intake manifold, but apparently it was a "complete redesign" of the old engine (so Wikipedia says). What does this mean? So yeah, any info on the specific differences between the engines would be good, thanks.

One of the other specific things I'm wondering about is the operation of the variable-length intake manifold. I assume I wouldn't get this functionality without swapping out the ECU. Is that correct?

Also, a quick third question. In the US, the Catera is equipped with the "4L-30E" transmission. Apparently the Omega B V6 has an "AR35" transmission. Are these the same things? And if so, then what is an AR25 in the other nomenclature?

[Marks DTM Calib]

A nice easy one, the core engine (e.g. heads, block etc) are the same design, the key differences are slightly larger bore and stroke plus a forged steel crank.

The standard 3.0 had variable inlet (multi ram) so this is the same.

The easy approach is to use the 3.2 as a core and swap the 3.0 engine components over and away you go (as the engine management system will be the same so will still operate correctly with the rest of the vehicle).

You will most likely have to do a very simple mod to the front pipes on the exhaust to make them mate to the 3.2 manifolds.

[Kevin Wood]

..and the answer the gearbox question, the AR25 and AR35 are both variants of the 4L30E gearbox.

AR25 was designed with a 250NM torque limit for the lesser engines, AR35 has a 350NM limit, for the 3.0 and 3.2 engines IIRC.

[05omegav6]

Being DBW, isn't the 3.0 in later Cateras not electrically identical to the 3.2... no SAI or EGR

[Marks DTM Calib]

Being DBW, isn't the 3.0 in later Cateras not electrically identical to the 3.2... no SAI or EGR

No, a few differences in injection setup sadly  .....plus as we know the 3.2 management setup is inferior to the 3.0 

[X30XE]

So the 3.0 ecu can work around the extra 200cc of engine capacity ? 

[05omegav6]

Being DBW, isn't the 3.0 in later Cateras not electrically identical to the 3.2... no SAI or EGR

No, a few differences in injection setup sadly  .....plus as we know the 3.2 management setup is inferior to the 3.0 

Only when fitted with the wrong gearbox ; D

[tigers_gonads]

Being DBW, isn't the 3.0 in later Cateras not electrically identical to the 3.2... no SAI or EGR

No, a few differences in injection setup sadly  .....plus as we know the 3.2 management setup is inferior to the 3.0 

Only when fitted with the wrong gearbox ; D

Bitch 

[biggriffin]

[/quote]
Only when fitted with the wrong gearbox ; D
[/quote]

Like what you already have,the Edwardian pudding stirred variety   

[ZaneKaminski]

Okay, this sounds quite doable. Can anyone provide any details on what needs done to the exhaust pipes to get it to fit together?

[Marks DTM Calib]

The top of the front pipes are likely to have a flange that sticks out circa 8-10mm around which is fitted the front pipe to manifold gasket, this needs cutting or grinding back to circa 3mm .

[ZaneKaminski]

Thanks for all the advice. I really appreciate it. I'm no mechanic (just a software engineer). How difficult do you think it'll be to remove the piece? What tool should I use? Like some kind of a file?

And does anyone know anything about the reliability of the 3.2 compared to the 3.0?

[05omegav6]

Far superior

[ZaneKaminski]

That's what I was thinking/hoping for. But why? What'd they change in the design? Or are they just manufactured better?

[Temetsy]

I think it's that Y32SE is the second generation v6 (or third if you think C25XE is first) and GM has fixed all the flaws and weak spots of the previous generation v6 engines. So it is basically just a better and bigger version of the old v6

[biggriffin]

Far superior

Me thinks Bentley,porch,and a few truck manufacters think different,o and the reading one.

[Broomies Mate]

Many people will disagree, but the 2.6/3.2 variant of the GM V6 only came about due to tighter emission controls in Europe.

It had nothing to do with more power...... the 2.6/3.2 have insignificant power increases to the 2.5/3.0 they replaced.

Total engine failure of the GM V6 is extremely uncommon.  Poor maintenance of the Cam Belt and associated pulleys/tensioners are the main reasons for the engines to fail.  That is across the board - I don't think there is any difference in longevity between the X30XE and Y32SE - Both are extremely reliable engines.

[05omegav6]

270k and counting on my 3.2... and that's with 10k oil and 80k belt intervals

Not driven particularly gently either

[Temetsy]

Many people will disagree, but the 2.6/3.2 variant of the GM V6 only came about due to tighter emission controls in Europe.

It had nothing to do with more power...... the 2.6/3.2 have insignificant power increases to the 2.5/3.0 they replaced.

Total engine failure of the GM V6 is extremely uncommon.  Poor maintenance of the Cam Belt and associated pulleys/tensioners are the main reasons for the engines to fail.  That is across the board - I don't think there is any difference in longevity between the X30XE and Y32SE - Both are extremely reliable engines.

I've heard two or three cases where the conrod has wanted some fresh air and breached out through the block.. Tho that surely is because of neglecting the oil change interval and use of the cheapest oil available 

[Andy H]

So the 3.0 ecu can work around the extra 200cc of engine capacity ? 

Yes 

[Andy H]

Many people will disagree, but the 2.6/3.2 variant of the GM V6 only came about due to tighter emission controls in Europe.

It had nothing to do with more power...... the 2.6/3.2 have insignificant power increases to the 2.5/3.0 they replaced.

Total engine failure of the GM V6 is extremely uncommon.  Poor maintenance of the Cam Belt and associated pulleys/tensioners are the main reasons for the engines to fail.  That is across the board - I don't think there is any difference in longevity between the X30XE and Y32SE - Both are extremely reliable engines.

I've heard two or three cases where the conrod has wanted some fresh air and breached out through the block.. Tho that surely is because of neglecting the oil change interval and use of the cheapest oil available 

Catastrophic connecting rod failure can occur as a result of a blockage in the oil supply to the crank - as the big ends run dry they overheat and seize at the same time - when the con rod is subjected to additional heat and stress as well as the normal stresses it lets go and punches through the block.

The gauze in the V6 oil strainer is prone to blockage. Poor quality oils will probably contribute to build up of crud in the sump. If you get an apparently good engine with unknown service history then it is worth dropping the sump and checking the strainer for piece of mind.

[Marks DTM Calib]

So key differences between the 3.0 and 3.2 (off the top of my head)

Larger Bore (not necessarily a good thing!)
Longer stroke
Steel mutlilayer head gaskets (a good thing although the composites are fine with regular coolant changes....which is needed anyway for the oil cooler and alloy heads!)
Forged steel crank (a good thing)
Improved exhaust manifolds (formed steel rather than cast - a good thing)
No air injection (possibly not fitted to US variants anyway and easily removed/got around - a good thing)
No EGR (neither good nor bad in reality as it causes few issues and only has a slight impact on throttle response)
Lower compression ratio (to overcome the loss of EGR, not a good thing!)
Later injection setup (not a good thing in my opinion as it is very emissions orientated and impacts economy)
Coil per plug ignition setup (a cost saving for GM only, not superior to the DIS but this was fitted to the 3.0 in the US anyway).

To modify the tops of the front pipe, an angle grinder with cutting disc works well or simply grind the lip back.

[Lizzie_Zoom]

All I know is my latest Omega with a 3.2 V6 is superior to any 3.0 V6 I have had in the past.

It sounds different, accelerates at a faster rate, and general out performs the others.  It is amazing what an extra 200cc and  years of engine development can achieve.

[Marks DTM Calib]

In which case your 3.0 was below par 

[Marks DTM Calib]

I should add that I suspect the optimum using stock parts is a 3.2 block with 2.6/late 2.5 heads (which have been ported) with 2.6/3.2 exhaust manifolds, 3.0/2.5 front pipes, 3.0/3.2 inlet setup, G cams on inlet and exhaust and 3.0 injection setup minus air injection and EGR. 

This gets the earlier higher compression ratio back with the earlier injection system plus maximum cc and best crank plus the most free flowing exhaust setup off the shelf and best inlet system off the shelf.

[omega3000]

So key differences between the 3.0 and 3.2 (off the top of my head)

Larger Bore (not necessarily a good thing!)
Longer stroke
Steel mutlilayer head gaskets (a good thing although the composites are fine with regular coolant changes....which is needed anyway for the oil cooler and alloy heads!)
Forged steel crank (a good thing)
Improved exhaust manifolds (formed steel rather than cast - a good thing)
No air injection (possibly not fitted to US variants anyway and easily removed/got around - a good thing)
No EGR (neither good nor bad in reality as it causes few issues and only has a slight impact on throttle response)
Lower compression ratio (to overcome the loss of EGR, not a good thing!)
Later injection setup (not a good thing in my opinion as it is very emissions orientated and impacts economy)
Coil per plug ignition setup (a cost saving for GM only, not superior to the DIS but this was fitted to the 3.0 in the US anyway).

To modify the tops of the front pipe, an angle grinder with cutting disc works well or simply grind the lip back.

Looking at that just makes me want to keep the 3.0 even more now , but then i knew it was superior 

[TheBoy]

All I know is my latest Omega with a 3.2 V6 is superior to any 3.0 V6 I have had in the past.

It sounds different, accelerates at a faster rate, and general out performs the others.  It is amazing what an extra 200cc and  years of engine development can achieve.

As I said to JamesV6CDX on another thread when he said similar, either you had a dog of a 3.0l, or your 3.2 is modified by Imber Tuning

[Lizzie_Zoom]

All I know is my latest Omega with a 3.2 V6 is superior to any 3.0 V6 I have had in the past.

It sounds different, accelerates at a faster rate, and general out performs the others.  It is amazing what an extra 200cc and  years of engine development can achieve.

As I said to JamesV6CDX on another thread when he said similar, either you had   dog of a 3.0l, or your 3.2 is modified by Imber Tuning

All I can say I have had multiple 3.0's, one just 3 years old when purchased, and my current 3.2 is as I have stated; better than all of them

[TheBoy]

All I know is my latest Omega with a 3.2 V6 is superior to any 3.0 V6 I have had in the past.

It sounds different, accelerates at a faster rate, and general out performs the others.  It is amazing what an extra 200cc and  years of engine development can achieve.

As I said to JamesV6CDX on another thread when he said similar, either you had   dog of a 3.0l, or your 3.2 is modified by Imber Tuning

All I can say I have had multiple 3.0's, one just 4 years old when purchased, and my current 3.2 is as I have stated; better than all of them

The 3.2 does give more power when just touching the throttle, making it seem quicker, whereas the 3.0l needs lots of throttle movement. But the 3.0l is quicker.

[Nick W]

I was surprised just how much difference the later manifolds with no other changes(other than blanking the EGR and dumping the SAI) made to my 3.0l.

[omega3000]

All I know is my latest Omega with a 3.2 V6 is superior to any 3.0 V6 I have had in the past.

It sounds different, accelerates at a faster rate, and general out performs the others.  It is amazing what an extra 200cc and  years of engine development can achieve.

As I said to JamesV6CDX on another thread when he said similar, either you had   dog of a 3.0l, or your 3.2 is modified by Imber Tuning

All I can say I have had multiple 3.0's, one just 3 years old when purchased, and my current 3.2 is as I have stated; better than all of them

No it isn't 

[05omegav6]

Oh yes it is...

Must be panto season again

[omega3000]

Quote from Mistress Lizzie 

All I can say I have had multiple 3.0's, one just 3 years old when purchased

It must have been knackered then  if i boot mine too much it would snap my neck 

[cnj]

my recollection of a 1996 3.0ltr elite, was the accelerating modes which came into about three stages, when your ready, lets go and ___kin hang on !! because when you got into the power band on kickdown she was flying, as somebody discovered on the a38 many years ago when my right foot was heavier.

[X30XE]

I should add that I suspect the optimum using stock parts is a 3.2 block with 2.6/late 2.5 heads (which have been ported) with 2.6/3.2 exhaust manifolds, 3.0/2.5 front pipes, 3.0/3.2 inlet setup, G cams on inlet and exhaust and 3.0 injection setup minus air injection and EGR. 

This gets the earlier higher compression ratio back with the earlier injection system plus maximum cc and best crank plus the most free flowing exhaust setup off the shelf and best inlet system off the shelf.

  Excuse my ignorance, but why would the 2.6 head be better than the 3.2 ?

[Temetsy]

I should add that I suspect the optimum using stock parts is a 3.2 block with 2.6/late 2.5 heads (which have been ported) with 2.6/3.2 exhaust manifolds, 3.0/2.5 front pipes, 3.0/3.2 inlet setup, G cams on inlet and exhaust and 3.0 injection setup minus air injection and EGR. 

This gets the earlier higher compression ratio back with the earlier injection system plus maximum cc and best crank plus the most free flowing exhaust setup off the shelf and best inlet system off the shelf.

  Excuse my ignorance, but why would the 2.6 head be better than the 3.2 ?

You get higher compression ratio 

[Marks DTM Calib]

Yes, the 2.6/late 2.5 head has a smaller combustion chamber so raises the 3.2 compression ratio back up to circa 10.8:1.

You do have to port the head slightly to get it to 3.2/3.0 flow spec (not hard) and it would be worthwhile fitting the 3.2/3.0 exhaust valves as they are sodium filled.

[kluku5]

This is what I did (not because I could but because I had to :/ )

Long story short:
My 3.0 engine block failed due to one blocked cat. I got a used block from a scrapper, they said it is 3.0. Now this was a completely naked block, with the insides in, no accessories on it.

I then sat the two blocks next to each other and saw right away that they are different. Upon closer inspection I discovered that the new block is actually 3.2.

 Since I had not time (and no money to spare) I slapped my 3.0 heads and accessories on the 3.2 block. So only the block and the insides of the block are 3.2, the rest is 3.0. Also put 3.2 head gaskets on since the 3.0 gaskets would be over the edge of the cylinder obviously.

The result: works just fine, with one little difference. When I did kickdown with the 3.0 block, the car changed gear right when it was about to hit the limiter. Now it actually lets the engine hit the limiter once or twice before it changes.

[Temetsy]

Are the exhaust manifolds same in Y26SE and Y32SE? I have thought of fitting new exhausts since the cast ones of X25XE's are almost as bad as it gets and 26/32SE's manifolds would be a lot cheaper than any aftermarket manifolds (for example martelius's manifolds cost ~1000€) but are the new v6 manifolds a lot better than older cast ones or do i just save up for aftermarket ones? And another question, does 32SE have G cams or some milder cams? Thanks in advance

[kluku5]

I'm not sure about gasket size, but the later mannies are pressed steel I think. The outer diameter should be about the same, but inside diameter is larger=more room for gases and flows better.

I thought about getting a pair for my engine, but time and resources were limited so...

Hopefully I never get the chance to open up the engine and replace them

[Lizzie_Zoom]

Quote from Mistress Lizzie 

All I can say I have had multiple 3.0's, one just 3 years old when purchased

It must have been knackered then  if i boot mine too much it would snap my neck 

Oh no, I used that fully believe me, three times on a works emergency when my speed on an empty, 0300 time on the M40 reached the designers maximum specification!

[elvin315]

Could you please clarify a few things for me? I have a 2001 Catera Sport with the X30XE/L81 V6 and I was wondering what is meant by "Front Pipes" and "G Cam"? I understand the bit about the 3.0 heads on the 3.2 block to raise the comp. ratio and the need to "port" the heads but we only have the cast exhaust manifolds here. Our only source for the 3.2L Y32SE/LA3 is the 2003-2004 Cadillac CTS. Do you know if it came with the formed steel manifolds?

NOTE
Any Catera owners thinking of using the 3.2L from the CTS: You must use the 3.0L's oil pan. The 3.2L's won't clear the Catera's crossmember.

[Temetsy]

Front pipes are the part of exhaust system between mannys and middle silencers and where the cats and lambdas are. G cams are X30XE exhaust cams that have more lift than for example X25XE's F and E cams. Very common and effective tune-up for v6 engines. If I have understood right 2.5 and 3.0 v6 engines have the cast piece of cr*p exhaust manifolds and 2.6 and 3.2 v6:s have the improved ones.

[elvin315]

Thanks Temetsy!

[elvin315]

Yes, the 2.6/late 2.5 head has a smaller combustion chamber so raises the 3.2 compression ratio back up to circa 10.8:1.

The only 2.5L version of the GM 54 degree V6 sold in the US comes from the Saab 9-5 turbo (B308). Will its cylinderheads raise the compression ratio to 10.8:1 on a 3.2L block?

You do have to port the head slightly to get it to 3.2/3.0 flow spec (not hard) and it would be worthwhile fitting the 3.2/3.0 exhaust valves as they are sodium filled.

Would you describe the porting proceedure? Does it change the size of intake or exhaust valves, or is it just a mild recontouring of the passages? Will the 3.0/3.2L valves themselves fit the 2.5L valve seats without modifications?

[Marks DTM Calib]

So to answer, the Saab heads should get your compression ratio back up (I say should as we don't have visibility here of any US specific mods that might have been done).

On the 1.8/2.0/2.2/2.5/2.6/3.0/3.2 Euro Ecotec engines, all the inlet and exhaust valves are the same size so the exhaust valves will fit no problems (plus they just don't wear on these engines so second hand is ok).

The porting procedure requires the inlet tracks opening out to match the inlet setup as the 2.5/2.6 track is slightly smaller than the 3.0/3.2.

And to correct an earlier post, the G cams were fitted to the 3.0 inlets (not the exhausts) and the 3.2 did not have the same cams.
 

[Matchless]

Just to add to the above,
All the cams are engraved with an identification letter near the drive end. There is also a number which I believe relates to the profile grinder it was made on so an A3 is an 'A' cam, G1 a 'G' cam etc. Can be difficult to see unless cleaned properly.

[elvin315]

Thank you all! This kind of info is hard to come by over here. There's such a negativity towards the Catera that good cars with minor problems are getting crushed everyday. It's very unusual to see one on the road. In fact I passed one today while returning from a doctor appointment with my Father. It was coming at me and when we passed the driver waved at me. I gave him the thumbs up. I almost crapped my pants. It was a Catera Sport, same year, same color as mine. My Pops thought I was having a stroke. You have no idea how rare a sight it is. I appreciate your help stirring interest in our cars and maybe keeping a few more on the road. They're all about "MORE POWER" here so maybe this info will inspire the DIY mechanics out there to breathe a little life into their Cateras. Thanks again.

[elvin315]

Last thing, I promise. Which Fuel Pressure Regulator should we use, and how much increased HP might we expect to see? Our L81 was robbed of 20HP and our top speed lowered to 120MPH so we'd like to get at least some of the power back if not the top speed.

[05omegav6]

Here, the 2.5/2.6 uses a 3 Bar regulator, and the 3.0/3.2 uses a 3.5 Bar regulator

[Marks DTM Calib]

Not quite right.

The 2.5/3.0 had a 3bar and the 2.6/3.2 had a 3.7 bar.

Upping the fuel pressure will give no extra bhp, it might give slightly better fuel atomisation and if you were struggling to fuel it at WOT it could help there to (but they don't stock)

[05omegav6]

My bad was off memory... which is clearly off

[Marks DTM Calib]

My bad was off memory... which is clearly off

Lol, I only know as I used to advise raising the fuel pressure on the C25XE in the Cav and Calibra and the best source was an FPR from a 2.6 or 3.2 

[elvin315]

Anyone willing to take a guess at the HP from this "Bastard" engine? (OK, sue me. I had another question.)

[05omegav6]

220 bhp ish

[elvin315]

The US spec LA3/Y32SE, as used in the CTS, is already rated at 220HP. I'm sure swapping the 3.2L heads for the 2.5L or 3.0L heads (with the G cams and sodium filled valves) would bump up the HP but by how much?

[Marks DTM Calib]

A well put together 3.2 with the increased CR and a little fettling on the inlet plus the better cams should see around 230-240bhp

[elvin315]

A well put together 3.2 with the increased CR and a little fettling on the inlet plus the better cams should see around 230-240bhp

Sounds good. Thanks.

[elvin315]

"A little knowledge can be a dangerous thing."

I gleaned a little knowledge about camshafts following you guys, made the mistake of digging deeper, and found this:



The chart lists the X30XE's 2x"G" & 2x"A" cams but there's no mention of the 4x"G" option. Forgive my ignorance but does 4x"G" mean using "G" intake camshafts as both intake and exhaust? Try not to laugh at the stupid Yank but I'd rather ask a dumb question now than do something even dumber later.

[Marks DTM Calib]

Yes, exactly that.

G's in both inlet and exhaust

[elvin315]

If I've got it straight the 4x"G" set-up will increase the torque and push it higher up the rev range, as well as increasing the HP. That's great news. I assume we use the timing marks on the exhaust "G" cam the same way we would on the "A".

Over here all the focus is on swapping in LS1 V8s or SC3800 V6s. I can count the finished V8 Cateras on one hand and no 3800s. Most owners think the L81 is a fragile piece of junk. Me, I love how it wants to rev. Cadillac castrated it electronically robbing it of power and top speed. At least this engine will give us back what Cadillac took from us.

I'm not in the position to do this yet but I have a cousin who's a mechanic and owns a Catera Sport like mine. He'll jump on this once I give him the details. Over the past few days you guys on OOF have opened the possibility of more performance from our L81.

Thanks for your help and your patience.