[paulmanchester]

I have a turbo that is on its way out. I have a 1992 cs carlsson (currently a garrett t25).
I love the low down urge but really hate the top end taper. The aero mitsubishi would be an obvious choice - but what others can I fit?
Would the elctronics need adjusting - its DI/APC not trionic with a different turbo.
Looking on ebay there are lots of different ones from various cars. Do I have to get a specicifc model to physically fit - or are they all interchangeable?What would need to be done to say a t25/28 hybrid turbo from a nissan 200?Is it just a case of a new exhaust connector thingy!?

 

[cdcarlsson]

Hi Paul,

Just a point, but even the Aero unit suffers from boost taper at the top end. Mine drops gradually from 1.15bar(max @ 2750rpm) down to 0.80bar (@ 5750rpm). It seems to be a function of the engine/turbo design.
As an aside it's definately more laggy than the T25 I had on the CD Carlsson as well, that car in second gear was absolutely fantastic with no lag whatsoever above 2250 rpm, but the Aero has a definate pause to it before all hell breaks loose.

Nick.

 

[paulmanchester]

in 2nd gear I have no lag at all. Just stupid acceleration.But above 4.5k it really trails off.
Which would give the quicker car?
Another model altogether?

 

[1989agoodvintage]

PKang has a T28/T3 hybrid on his CS Carly. I remember him saying that the car seemed quicker but there was a lot more lag. Personally I'd go for a TD04-15 or a T25/T28, so not to lose too much low end torque. Ideally, to get to around 300bhp (my personal target), peak boost needs to increase 25% and needs to shift from 2K-3.5Krpm up to 3.5Krpm up to 5000krpm, with the boost dropping off to base levels from 5000 to 6000rpm.

Don't know if I could acheive this with any of the turbo's or hybrids around. I guess I'd have to ask.

Best of luck Paul. Hopefully some peeps with experience using hybrids and larger turbos will be online shortly to provide some input.

 

[paulmanchester]

what is the difference between t25 and t28 and what is a t25/28 hybrid.

 

[mark e]

It's not just the turbo that causes taper at high revs... it's the intake system and head design. The turbo has to overcome intake resistance at all revs. Lower the resistance and it will be able to pump more air in to the combustion chamber. Use the Mitsu and a high flow intercooler and you will notice a huge difference.

 

[cdcarlsson]

Originally posted by paulmanchester(now cockermouth):
[qb]in 2nd gear I have no lag at all. Just stupid acceleration.But above 4.5k it really trails off.
Which would give the quicker car?
Another model altogether? [/qb][/b]

This is just as I remember my Carly Paul, no point at all revving the nuts off it, just change up around 4500...
The TD04-15 gives far more top end BUT you MIGHT regret the lag it introduces the rest of the time.
It all depends on the driving you do. Like many things in life, it's a compromise.

Nick.

 

[paulmanchester]

I would like to run higher boost which would be best? - although I liked the charecteristics of mine. Would a 9k aero be very similar to a carly with a mitsibushi turbo? If so I will try and test drive 1 asap.

 

[1989agoodvintage]

Originally posted by paulmanchester(now cockermouth):
[qb]Would a 9k aero be very similar to a carly with a mitsibushi turbo? If so I will try and test drive 1 asap. [/qb][/b]

No, the Carly's with the Mitsu turbo's were all 2.0litres and it's a different unit in the TEO5-12B rather than the TD04-15.

 

[1989agoodvintage]

Leading on from this, what Paul and I will need to know is what Jetronic and APC (if any) software is needed to get our cars running properly with uprated turbo's. For me this is something that is quite a way off, unless god forbid my T25 develops a bad smoking habit as well!!

Is there anyone out there with relevant experience in upgrading turbos on DI/LH/APC cars?

 

[California Saab Tuner]

It's not just the turbo that causes taper at high revs... it's the intake system and head design. The turbo has to overcome intake resistance at all revs. Lower the resistance and it will be able to pump more air in to the combustion chamber. Use the Mitsu and a high flow intercooler and you will notice a huge difference. ---Mark E

Or more to the point, it's the software that controlls the turbo pressure.

Any restriction after the pressure sensor will show up as a power taper even when the boost stays constant. While high flow IC will cause the sensor to see more boost, it would adjust back down to the factory boost curve and you'd just see more efficient cooling and less compressor backpressure, rather than more flow or boost.

A larger turbo is a good idea. Too many people complain about lag. Lag isn't bad! If you really wanted to go someplace quickly it's probably best to put it in a lower gear anyway. Just don't pick a compressor that's too far outside the power range for your engine and you should be fine.

If you want something that spools a little quicker than the TD04 from the Aero, try the one from the Viggen. With the right manifold it should bolt up nicely and I know from experience that it spools quite quickly.

With the 2.3L B235R even on factory T7 software it will hit 15 psi at about 2,200 rpm. Also, while the factory software has a boost taper, the Viggen turbo has enough puff to put it easily up to 280-300 hp when tuned really well as the Taliaferro Viggen clearly shows.

Even on a 2.0 the Viggen turbo hits 18 psi by about 3,000 RPM. Not too shabby if you ask me.

I think you oughtta go with an Aero turbo personally, as I find the Viggen turbo to spool TOO quickly for my taste. But just letting you know there are other options!

Cheers and Good Luck

Dubbya

 

[Mark in Ireland]

I'm interested in the discussion on turbo options and as most of you know I have a Variable Vane turbo hybrid to fit at some stage but will need a bespoked exhaust downpipe fabbing up and don't have to time or resources at present, however, after filling the car with super unleaded and getting neat methanol for my water injection kit and running 50/50 mix I find the difference at the higher rev range now rather pleasing..

The car feels as fast in 4th now as it did in 3rd...its so manic I haven't been able to see what boost pressures I'm hitting as I'm too busy holding on!

 

[Kang]

I have a CS Carlsson with a T3/28 Hybrid there is a little more lag than the t25 turbo but much more welly up top and I am able to run higher boost.

The new turbo has definatley nade the car quicker in terms of top end and acceleration.

Good luck

All the best

Paul K

 

[1989agoodvintage]

Originally posted by Kang:
[qb]I have a CS Carlsson with a T3/28 Hybrid there is a little more lag than the t25 turbo but much more welly up top and I am able to run higher boost.

The new turbo has definatley nade the car quicker in terms of top end and acceleration.

Good luck

All the best

Paul K [/qb][/b]

Paul, are you using an MBC or have you got modified APC software for the T3/T28?

 

[mark e]

The thing about restrictions is that they make the turbo work harder and therefore, crucially, hotter. Thus the intake air temp rises and power drops either a) as a result of less mass going in to the cylinders or B) raised temps causing pre-ignition which the software then responds to by lowering the boost.

Rather than use something with more "shove", why not first reduce the restrictions on the current unit. I have noticed a big difference doing this

.

 

[1989agoodvintage]

Because (from my point of view):

1) I can't afford a new IC
2) If my turbo breaks I will need a new one
3) I would rather buy a new higher spec turbo than replace with a recon T25

Of course if I have a chance of getting an uprated IC second hand I will go down that route. I imagine that Paul is in much the same situation as myself.

This is not an ideal path to follow, I realise that. Unfortunately I have to live within my means. Perhaps I should not bother trying to increase my cars top end power in that case?

 

[mark e]

Jase,

Sorry, I should have been clearer... I was mainly responding to Adrian's comments and adding more to what I first said, which was highlighting an area of shortfall in the "standard" system. The high-end free-revving of my car is as much down to the low resistance as it is to turbo capacity . Based on my experiences, I would say that using a slightly bigger turbo with lower resistance is a better bet than simply relying on pure turbo grunt to get more air in to the cylinders.

 

[1989agoodvintage]

Ah, it makes sense now. Ta.

 

[Kang]

Jason I have a mbc on the car.

 

[zeke]

Here's a vote for the TD04 (6 cm^2). Boost taper - mine tapers down to around 1.15 bar at the red-line. The MHI has plenty more puff in it and only needs software changes in the T5 to 'liberate'

Turbo-lag: even with the 6 cm^2 turbine, lag is not an issue if one knows the boost programming and can use their shifter accordingly. My boost is at 1.2 bar @ 2200 rpms - there's, undoubtedly, more lag from the boost control (APC solenoid) circuit than from the Mitsu' - so turbo lag is really a non-issue. The 15T is more than sufficient for over 300 hp and for the price, is hard to beat.