What bhp and torque are people running on xman750 gtb2260

I'll have to report back once my mapping is complete and I've put it on the rolling road! Still on standard injectors too.

 

It's hugely quicker over a PD150 hybrid setup though I'll say that much!!

I'll have to report back once my mapping is complete and I've put it on the rolling road! Still on standard injectors too.

It's hugely quicker over a PD150 hybrid setup though I'll say that much!!

It what way Alex?

PD150 hybrids make 210-220bhp with the right mods.

Can't go much above that without injectors.

Is just down to the spooling?

You will get a touch over 240 with a gtb and standard injectors.

 

I think its a little decieving though as to being alot quicker. The main difference, I feel, is the torque is held for longer giving that feeling of being pulled along

I think it's down to the mapping as well to be honest Richard.

 

My old hybrid made 219bhp on the rollers. It used to bore me somewhat though, as when you got to the top of the rev range it just seemed to die a death. Which took the fun out of it for me and almost lead to me selling up and going back to petrol!

 

The 2260 is yet to go on the rollers, but it pulls so much harder at the top of the rev range it's unreal! Must produce at least 20bhp more at a guess. Loads more torque I think too.

 

Spooling wise, it does take a bit longer to come on full boost. However, it comes on boost very progressively. This turbo and mapping is actually more tractable than the old hybrid in my opinion.

 

Dan and I had a blast when I was running my old hybrid setup and him running the GTB1756, and he left me pretty easily to be honest.

It what way Alex?

PD150 hybrids make 210-220bhp with the right mods.

Can't go much above that without injectors.

Is just down to the spooling?

The Gtb is much bigger, so it gives you power all the way through the revs.

The pd150 might peak at 210-220bhp but the power then drops off rapidly.

One of the things you notice when you convert to a Gtb is how easily you hit the rev limiter, as the car is still pulling right through the revs.

What bhp and torque are people running on xman750 gtb2260

 

Dude, numbers, seriously?

 

Everyone and his dog will tell you a bigger turbo is better until you go too far and the damn thing won't spool properly any more.

By far the most important factor on a road car is the spread of power, this equates to the linearity of available torque, this coupled with low latency provides the best driving experience and is far kinder to the drivetrain.

All a bigger turbo does is take a chunk of the torque higher up the rev range so it starts later and finishes later, in a perfect world you want the power to fall off just before the engine runs out of revs, on a diesel this is much earlier than a petrol due to the much slower burn of the fuel.

You can fit a turbo like a dustbin lid if you want and you'll make huge peak power but the car will undriveable and eat clutches and smash gearboxes.

 

So just forget numbers and focus on the drive.

One of the things you notice when you convert to a Gtb is how easily you hit the rev limiter, as the car is still pulling right through the revs.

 

Oh yes!  I was doing some data logging yesterday and I couldn't find where power stopped.  It wasn't until I was popping off the (raised) limiter I got back off the throttle.  Sure they don't come on proper full boost until after 2500rpm but what you lose at the bottom you gain at the top.

The GTB's make the car far more drivable from what I've experienced. They seem to be very well suited to the car!

Makes it more like a petrol to me.  Sure you lose the serious low down torque, but for me, my car still pulls OK at 1500 revs so it doesn't bother me.  

That's exactly my opinion on how it drives - more like a turbo petrol motor now.

 

As you say, it drives perfectly fine - no issues at all driving it around town. The hybrid had a huge kick at about 2.2k revs, which made it quite difficult to get the power down to be honest.

I think it's down to the mapping as well to be honest Richard.

My old hybrid made 219bhp on the rollers. It used to bore me somewhat though, as when you got to the top of the rev range it just seemed to die a death. Which took the fun out of it for me and almost lead to me selling up and going back to petrol!

The 2260 is yet to go on the rollers, but it pulls so much harder at the top of the rev range it's unreal! Must produce at least 20bhp more at a guess. Loads more torque I think too.

Spooling wise, it does take a bit longer to come on full boost. However, it comes on boost very progressively. This turbo and mapping is actually more tractable than the old hybrid in my opinion.

Dan and I had a blast when I was running my old hybrid setup and him running the GTB1756, and he left me pretty easily to be honest.

No you left me! I didn't realise we were supposed to be in 2nd gear then I caught up quite easily. The way yours pulled though with that torque curve made it feel really fast. I think mine is slightly smoother but yours definitely felt faster even with that SMIC setup!

Definitely goes well with that 2260 though and that was on your old map. Quick enough to embarrass that young lad and his girlfriend in the VXR anyway :P

The GTB's make the car far more drivable from what I've experienced. They seem to be very well suited to the car!

I was shocked at how low down the power came on with your 2260, I remember the big horror talk of people saying there will be no power under a certain rpm etc etc, this is definitely not the case and like you said makes it more drive able if anything!

That's exactly my opinion on how it drives - more like a turbo petrol motor now.

 

As you say, it drives perfectly fine - no issues at all driving it around town. The hybrid had a huge kick at about 2.2k revs, which made it quite difficult to get the power down to be honest.

 

I'd be curious to see a group 11 log of your turbo.

Ask and you shall receive....

 

 

 

 

Mapping is not finished yet don't forget! John's been slowly upping the boost up the revs, so more will come higher up if he's happy

I was shocked at how low down the power came on with your 2260, I remember the big horror talk of people saying there will be no power under a certain rpm etc etc, this is definitely not the case and like you said makes it more drive able if anything!

It's mostly down to the good mapper imo

And his research on actuator settings

John (Faboka) has been very accommodating and fantastic to deal with for the mapping! The final map is going to be spot on  Pretty damn good at the minute already!

 

Dunno about this actuator research malarkey though :P

Looks a smart boost curve.  Mine looks to be coming in fractionally later but that could be down to either mine being the 2566vk hybrid, or that simply there's a little more setting up to do.  Mine only currently peaks at 3000 (as running a 2 bar map for testing) but it shows a very similar climb of boost.

 

At the moment mine looks to be:-

 

1 bar at 2200rpm

1.4 bar at 2500rpm

1.8 bar at 2700rpm

2 bar at 3000rpm and holds steady to 5061rpm

 

I think my limiter is set to 5100 but I might get that raised a bit  I see yours is 5300

Looks a smart boost curve.  Mine looks to be coming in fractionally later but that could be down to either mine being the 2566vk hybrid, or that simply there's a little more setting up to do

What % is your actuator at 4000rpm on a WOT log?

 

Dunno about this actuator research malarkey though :P

#unt

What % is your actuator at 4000rpm on a WOT log?

 

My duty cycle is about 72% at 4000rpm (+/- 2 %) which is apparently bang on.  Not bad considering it was set up using a vacuum gauge at a suggested level.  Only the stopscrew has needed winding out about 225 degrees to encourage earlier boost.  It might still need bringing out more.

#unt

 

He's your aunt? :P

He's just jealous of my follicles...

Ask and you shall receive....

 

 

 

 

Mapping is not finished yet don't forget! John's been slowly upping the boost up the revs, so more will come higher up if he's happy

 

See it in graph form. Worth mentioning this is boosting higher then what XMAN recommends (2.2bar) but Alex is greedy Aiming for smoke free so EGT will be sensible.

 

Going of the logs from Alex's car and running it through some calculations to work out volumetric efficiency I predict the following. This is aiming for little to no smoke and assuming no other bottle necks to the airflow the higher up the boost you go.

 

1.8 bar - 220 bhp

2.0 bar - 235 bhp

2.2 bar - 250 bhp

2.4 bar - 265 bhp

2.6 bar - 280 bhp

2.8 bar - 300 bhp

3.0 bar - 310 bhp

Considering I've been running at 2.45bar in the mid-range, how have my injectors been coping John?!

 

As I noticed quite a difference in performance when you upped it from 2.2!

 

I'm definitely greedy though  Might as well make the most of what you've got!