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[MikeyBikey]

Hi all. As per my project thread I've fitted a y32se to my scimitar.  I have open headers, straight through 2" exhausts, large k&n, and an aftermarket ecu to switch between lpg and petrol.

It's brilliant and once I've mastered picture hosting and  my new phone I'll post some pictures.

My question is, to gain more power its been suggested to fit higher compression heads from a 2.5 ? I've researched and its clear every engine variant of the v6 has different bores. So how do i identify the correct 11.5 compression heads from all the others and despite differences in bores, will it fit the 3.2

Thank you

[Doctor Gollum]

You've done about all you can with the Omega V6.

The 2.8 turbo would be an option but it's configured for front wheel drive.

2.3 Saab Turbo lump is readily tuneable and gives significantly more power.

[Nick W]

DG is pessimistic as there is plenty more you can do, especially as you don't need the modifications to work in an Omega.


But it is traditional tuning; cams, properly modified(more than 10minutes with a Dremel) heads and better induction. Those are all available, but are expensive and very expensive when you consider the fairly small gains. You need to discuss your intentions with the part suppliers before making any changes.


Just increasing the compression ratio just by itself won't do much

[Doctor Gollum]

Pessimistic is a bit harsh 

2.6 heads will give you the compression, but your limiting factor is getting enough air in to be able to add more fuel.

[Nick W]

Pessimistic is a bit harsh 

2.6 heads will give you the compression, but your limiting factor is getting enough air in to be able to add more fuel.

better porting, bigger valves, performance cams, individual throttle bodies. That should break 300bhp, but will also break £5k.

[Migv6 le Frog Fan]

Pessimistic is a bit harsh 

2.6 heads will give you the compression, but your limiting factor is getting enough air in to be able to add more fuel.

better porting, bigger valves, performance cams, individual throttle bodies. That should break 300bhp, but will also break £5k, and the bottom end.

Fixed. 

[MikeyBikey]

Thank you all. Is another option, maybe, depending on your Informed input,  fitting the asymmetrical turbo  from the 9-5 3.0 petrol turbo.? I have the manifold and turbo, on the garage shelf. With all the extra gubbins (intercooler blow off valve etc,) would it work on a y32se

[MikeyBikey]

I understand as I'm using lpg, having a compression ratio of 10.1 is not an issue with forced induction.

Cheers

[VXL V6]

I believe the main problem with pushing the 54 degree V6 is that the cooling around Cylinder 6 is marginal.

[MikeyBikey]

Thank you vxl. Ironically that's the external location of the turbo, if I were to fit it.

[Nick W]

Thank you vxl. Ironically that's the external location of the turbo, if I were to fit it.

that's a peculiar place for a single turbo, especially in a Scimitar. You could probably swap the standard exhaust manifolds side to side, join the downpipes in front of the water pump and put a big turbo there.


The standard Saab turbo is designed to boost mid-range torque and will run out of puff at high rpm, whereas your use suggests you want more top end

[Raeturbo]

You would probably be better off trying to get a small supercharger on it instead. You won’t need an intercooler if you’re only going to run about 6 or 7 PSI. And every 3.9psi will raise compression ratio by 1 so you can have 11.1 with just 4lbs. Which should give around 30/40 bhp with a nice dollop of torque and broaden the power  band. Don’t know how much room you have there but some of the early toyotas use a nice little unit👍 Of course you will need to get it mapped to get the most out of it.

[Nick W]

You would probably be better off trying to get a small supercharger on it instead. You won’t need an intercooler if you’re only going to run about 6 or 7 PSI. And every 3.9psi will raise compression ratio by 1 so you can have 11.1 with just 4lbs. Which should give around 30/40 bhp with a nice dollop of torque and broaden the power  band. Don’t know how much room you have there but some of the early toyotas use a nice little unit👍 Of course you will need to get it mapped to get the most out of it.

Superchargers are harder to size to application, and much harder to fit especially to a V engine. You also have to consider how much power they absorb to make that 40 hp. That's a small enough increase that could be achieved by aftermarket cams and some head work. Which is simple bolt on work, albeit fairly costly.

[Raeturbo]

Indeed swings and roundabout, second hand sc can be found but how much room is there to fit ....... cams and porting will give you power up the top end.. whilst more boost will give nice midrange shove. I think Vauxhall missed a trick with this engine I feel it could have been a nice 240/250BHP if they used a bit of imagination👍

[TheBoy]

I know the 3.2 has a stronger crank and a lower CR to start with, but remember those idiots at Courtney plopped a turbo on some of the early 3.0 cars, and all quickly suffered bottom end issues.

[Migv6 le Frog Fan]

Hence reply number 5. 

[Doctor Gollum]

Stick a proper engine in it

[Raeturbo]

4G63T

[Doctor Gollum]

4G63T

I said a proper engine, not a blow drier

[Nick W]

4G63T

I said a proper engine, not a blow drier

Don't forget that Mitsubishi is Japanese for "that will cost three kidneys. You have two, who is providing the third?"

[Raeturbo]

😂😂. At you both I’m mid elevens now with my hair drier 😂

[Andy H]

I know the 3.2 has a stronger crank and a lower CR to start with, but remember those idiots at Courtney plopped a turbo on some of the early 3.0 cars, and all quickly suffered bottom end issues.

it puzzles me when people claim that the omega v6 has cooling issues (meaning the water cooling) - if that were true we should see lots of head gasket failures due to cooked engines.
What they do have is an oiling system that is about right for a 200bhp v6. V engines pack two big ends into the space  where an inline has only one. If you want to generate significantly more power you need to increase the oil flow to give the bearings a chance and to provide more cooling to the piston crowns.

[Doctor Gollum]

2.5 and 3.0 engines of a particular build series suffer from external head gasket failure around the rear of the 246 head... Seems to be almost as guaranteed as crank sensor failure.

That said, the only people who have managed to break a 3.2 have the mechanical sympathy of a volcano.

'Buying the car new twenty years ago and immediately replacing the coolant with rock hard tap water and the oil with ATF and never changing either whilst driving everywhere flat out with the gearbox stuck in 2nd' type of abuse.

[TheBoy]

2.5 and 3.0 engines of a particular build series suffer from external head gasket failure around the rear of the 246 head... Seems to be almost as guaranteed as crank sensor failure.

Not really, and probably not heat related.  MY97.5 3.0l (only) seem a little prone, though not "common" - I think on OOF, we can count maybe a maximum of half a dozen instances, with 2 of those being mine. 1 was MaxV6, I think JamesV6CDX came across one (actually, that might have been MaxV6's)....

[Nick W]

2.5 and 3.0 engines of a particular build series suffer from external head gasket failure around the rear of the 246 head... Seems to be almost as guaranteed as crank sensor failure.

It doesn't matter if you're going to lift the heads for performance modifications....
In fact, an engine that already has such a failure would be a good, cheap buy as it would be worthless to anyone else.


Tuning a 2.5/2.6 is pointless.

[Varche]

What about losing weight off the car.

There must  be a lot of weight you could pare off?

[VXL V6]

Tuning a 2.5/2.6 is pointless.

^^^^ This!

Had a 2.6 with G cams etc etc, just no comparison to a 3.2, makes the right noises but that's about it.

[Migv6 le Frog Fan]

What about losing weight off the car.

There must  be a lot of weight you could pare off?

Has to be the best way to make an Omega faster. Its a very heavy car, and quite al ot of that weight could be shed if you dont mind losing a bit of luxury.

[Nick W]

What about losing weight off the car.

There must  be a lot of weight you could pare off?

Ever been in a car with a stripped interior? It's like climbing into a steel oil drum and having a football team beat the outside with baseball bats. There are sharp edges every where and it looks shit.


You would have to really need any marginal performance increase to put up with one.


I've never understood the fascination of trying to turn a big, comfortable heavy small(ish) engined saloon into a track and road  car by removing all the features that were the original appeal.


And yes, I have tried removing the interior for an increase in performance. We did it at the track during the lunchtime shutdown. Taking all four seats, carpet, sound deadening and the door cards made no difference to 1/4 mile time of a 2.0l Capri, which as a low power car should benefit.

[Migv6 le Frog Fan]

Capri was light as a feather compared to an Omega though. One Omega front seat probably weighs as much as a complete Capri interior.
I agree about trying to turn a big heavy comfy barge into a track / fast road car though.
Its a bit like the old Irish joke "can you tell me the way to Dublin please ?"
"Well, I wouldnt start from here." 
However, if someone really wants to do it, shedding weight would be the best way to go imo.
Not just for straight line performance, but also for braking & cornering.

[Doctor Gollum]

Capri was light as a feather compared to an Omega though. One Omega front seat probably weighs as much as a complete Capri interior.
I agree about trying to turn a big heavy comfy barge into a track / fast road car though.
Its a bit like the old Irish joke "can you tell me the way to Dublin please ?"
"Well, I wouldnt start from here." 
However, if someone really wants to do it, shedding weight would be the best way to go imo.
Not just for straight line performance, but also for braking & cornering.

Only by removing structure, and the Omega doesn't have much of that to begin with, GM preferring to use less, thicker gauge steel than adding reinforcement.

The Barge weighs the same as an Omega but has significantly more metal behind the scenes.

Incidentally, the car in question is a Scimitar, so isn't exactly over weight... The 3.2 should already be a significant upgrade from an Essex V6.

An LS1 with a cam would be nearly twice the output of a 3.2

And about the same price as getting another 30bhp from the 3.2

[Varche]

What about losing weight off the car.

There must  be a lot of weight you could pare off?

Ever been in a car with a stripped interior? It's like climbing into a steel oil drum and having a football team beat the outside with baseball bats. There are sharp edges every where and it looks shit.


You would have to really need any marginal performance increase to put up with one.


I've never understood the fascination of trying to turn a big, comfortable heavy small(ish) engined saloon into a track and road  car by removing all the features that were the original appeal.


And yes, I have tried removing the interior for an increase in performance. We did it at the track during the lunchtime shutdown. Taking all four seats, carpet, sound deadening and the door cards made no difference to 1/4 mile time of a 2.0l Capri, which as a low power car should benefit.

Yes I have several times.  Even down to getting rid of the heater, blower etc. Agree not very comfortable.

[Nick W]

Incidentally, the car in question is a Scimitar, so isn't exactly over weight... The 3.2 should already be a significant upgrade from an Essex V6.

An LS1 with a cam would be nearly twice the output of a 3.2

And about the same price as getting another 30bhp from the 3.2

A stock 2.2 is a significant upgrade from a stock Essex. While an Essex can be improved, it was always expensive due to the number of parts that need to be replaced. And you've still got an engine that weighs more than a SB Ford and 8s far more fragile.


These days, if an LS fits there's little point in fitting anything else. That's especially true if you  think you want more than 400hp.

[Raeturbo]

2.5 and 3.0 engines of a particular build series suffer from external head gasket failure around the rear of the 246 head... Seems to be almost as guaranteed as crank sensor failure.

Not really, and probably not heat related.  MY97.5 3.0l (only) seem a little prone, though not "common" - I think on OOF, we can count maybe a maximum of half a dozen instances, with 2 of those being mine. 1 was MaxV6, I think JamesV6CDX came across one (actually, that might have been MaxV6's)....

[/quote

                 Yes mine I know how to break em . He’s done a great job though it hasn’t  missed a beat since I got it back from him about two years ago.

[MikeyBikey]

Thank you for the input. I have managed to get some pictures uploaded into my original thread here

https://www.omegaowners.com/forum/index.php?topic=145065.msg1990231#msg1990231

I'm really keen to understand how to get a little more performance out of the Y32SE but not sure to carry on this thread or merge with my original ? Mods night have a view.

I've purchased the turbo and manifold from a 3.0 9-5 saab. It fits the Y32SE but fouls the engine mountings so i cant use it. (Of course its designed for FWD and I have RWD) ! Also its bleddy tiny (1.25 ID output)  So not worth the effort.

There was a suggestion of better cams (aka exhaust ??) The cams i have on the Y32 all have 10 mm lift as standard ?

And or using X25XE heads for better compression. Wikepedia has just about every compression ratio going for the X25XE including some at 11.5. If I'm not going turbo but stick N/A how do I identify the correct ones for 11.5? Is their a GM casting number etc.

cheers

[Doctor Gollum]

Is the issue down to losing the multirams

They ostensibly flatten the torque curve...

[Doctor Gollum]

You notice when one or tother isn't working...

Some info here:

http://www.omegaowners.com/forum/index.php?topic=90513.0

[Kevin Wood]

Even if you don't fit the whole "bagpipes" a setup, getting the rear multiram working might gain you a bit of grunt at the top end.
All it needs is an RPM dependent output from the ECU to bring it in and open the valve at higher revs.

Having seen your video, low down torque doesn't appear to be a priority so the whole bagpipe setup might just be more restrictive and lose you power at high revs.

Do make sure you keep the intake temperature as low as possible too. Make sure it's not breathing air that's been through the radiator.

[MikeyBikey]

Hi Kevin, thank you.

At the moment there is no rear multi ram. Or any, actually.  It's blanked off. Part of the clean engine bay look (photo already loaded) meant I removed anything superfluous eg power steering, aircon and of course sensors etc. So knock, cam and air rams all went as well.

[Doctor Gollum]

Fit the short plenum from the pre face-lift,  and you should gain enough room to refit the front multirams.

If you run the intake through the inboard headlights (Dodge Challenger Stylee) that could give you a cold intake for each bank with the front multirams where the current intake is just short of the throttle body...