[Mk2] [Turbo] re: Stage 2 Hybrid CT26 spool

[Total Recall]

Hi.

Well thanks to the info from on here my 93 Rev 2 turbo is all up and running and I`ve done a few hundred trouble free miles this past week.

So, now I get to the bits I really don`t know anything about.

This is the first time I`ve had a non standard MR2 turbo - my others were both stock (appart from the usual decat and 1 bar of boost) - Rev1 and Rev2 turbos.

The car apparently has a stage 2 hybrid ct26 but doesn`t appear to have any other supporting mods which can`t be gud lol.

Still, before I decide whether to upgrade everything else I need an idea if the characteristics of this turbo are normal (in which case I`ll put a stock turbo on it) - or if there could be some other problems that I need to sort out that will change how it performs.

It doesn`t spool up until just under 4,000 rpm. Once it gets there it makes boost fast - and setup at 1 bar holds it well past 6000 - or as far as I dare go without any other mods, so no doubt to the redline if I let it.

The trouble is I`m a bit of a grandad driver lol and preferred the mid range of my previoius ones - I`m pretty sure they spooled up under 2500 and easily made 1 bar by 3000 - maybe a bit b4 and the fact they tailed by 5000 didn`t really bother me. I definitely had decent boost in 4th not much over 40 MPH - where as this one I have to be doing nrly 70 b4 it comes in and tbh for me isn`t as much fun.

The trouble is I don`t know anything about the turbo - and I`m not sure what to look at to be able to tell. I`ve looked at the descriptions on various stage 2 CT26`s available and most state full boost not much over 3000 - or at the very least 1 bar by that point.

So, what should I be checking - or could this just be how this turbo`s meant to perform ?

The only other info that might help is this is the first time I`ve had an electronic boost controller - a Gizzmo IBC - though I have tried it with my old mbc to see if it performed any different - and it builds boost a touch quicker but still not b4 about 3750 rpm.

I`ve also noticed there`s much less induction noise from this turbo - despite having a K&N as my previous ones. Is this a side effect of having a bigger turbo - will it spin at a slower speed to achieve the same boost? The sound is much more distant for some reason.

I just need a starting point so I`m not running round in circles chasing a problem that isn`t really there - or risk changing out a good turbo for an unknown condition stock one when it`s not really a turbo problem....

Thanks!

Dom.

[Peter Gidden]

The trouble is I don`t know anything about the turbo

And unfortunately, nor does anyone else. "Stage 2" in reality, means absolutely nothing.

The olny true way to know what you've got is to have the turbo looked at professionally. Then the compressor and turbine wheels can be checked for sizes and modifications.

[Keljon]

have a look on the turbo and se of there is a plate with the serial number and / or model number (turbo technics for instance do this) if there is then the builder will be able to tell you everything you need.

[Total Recall]

Hi, thanks for the replies.

I`ve had a gud look on both sides and underneath and can`t find any labels on it - other than toyota ct26 on the housing.

It looks like its going 2 b 1 of those mysteries until I take it off and get someone to look at it.

It won`t have to be taken appart to tell what it is will it?

One other thing - in the ad for the car it said it had run 230 rwhp @ 9 psi. Obviously I didn`t buy the car on this basis - I would have been perfectly happy if it was stock, I just liked the car lol - but I didn`t think 230 rwhp @ 9psi sounded right - do u think 0.9 bar will have been more likely - thats about 13 psi isn`t it ?

Cheers,
Dom.

[Keljon]

Have a look at these threads
http://www.imoc.co.uk/forums/viewtopic.php?p=817977
http://imoc.co.uk/forums/viewtopic.php? ... 0aab9685c3

[Total Recall]

Hi, thanks so much for those links!

After looking through them I went out and took the pipes and downpipe off to have a look for myself.

I have a couple of measurements - they`re not precise - but to within a couple of mm - which I know isn`t too helpful when working out what turbo I have - but - along with the pics, would you say that my turbo seems to be completely stock after all?

The visible part of the compressor wheel is about 41mm - (give or take a mm) and the visible part of the exhaust turbine about 51mm.

The only markings I can find are 14020 on the exhaust housing and 3B2 on the wastegate - oh and Y386108 on the acutuator.

Obviously the dyno quote must have been from a different car or the same car with a different turbo!

If it is stock then I`m surprised it can hold a bar past 6k though - unless my old cars` turbo`s were past it which is why they tailed off at 5k?







I did wonder if my rev counter could be out with it also not appearing to boost properly until near 4k - but the speeds for the gears seem correct at the rpm - and also I think I may have found why it boost so late.....

Firstly should I be able to move the wastegate about 5mm without moving the actuator rod? I would have thort that the wastegate should be pulled tightly by the actuator rod with the engine off? I don`t mean I can move the rod - just the wastegate.

It looks like there is a little play where the rod connects to the wastegate lever. If so, can the actuator be adjusted in its postion or is there any way to adjust the rod? I figure this could be why the car is boosting late ?

Also as you can see in the pics of the downpipe it has a few cracks - not sure if they can be welded. Looking closer on the first pic is that where someone has ground away to stop the wastegate fouling - and gone a bit too far?





Am I better off just buying a stock downpipe with the cat removed? I`m not bothered about a few extra BHP unless it makes a massive difference. I seem to remember on my old cars there was a seperate elbow I would need from the turbo aswell.

Anyway if anyone can put me right either way on the above assumptions, that would be great.

Also if there`s anything else I should check while the pipes are off....

Cheers!

Dom.

[madmr2man]

Hi mate

I've just been out and measured my old ct26 that's on the garage floor, seems to be 41mm inducer diameter and around 51mm exhaust, the same as yours.

I know mine is standard, and I have to say that imo, yours looks to be standard as well.

Mines also a rev2, and dies, howevrr, have a different actuator part number, W62026?

Maybe those cracks are leaking enough gas to not spin the turbo up properly?

[Keljon]

Looks stock to me and post above seems to confirm it, waste gate should be pulled tight shut.
I have one of those cheap eBay down pipes and while they do flow better as well as remove the cat, they always crack. I welded over all the welds on mine with a mig but it will only be a matter of time until it cracks again. Berk are generally considered one of the best as they are better quality and have a flexi.

[Total Recall]

Ah awesome thanks guys.

Getting excited now - despite it being just a stock one, I know I should get my mid range back once the problems are sorted - power coming in at 4k isn`t suited to my lazy driving style!

Will decide what to do with the downpipe - was easy to take off this time but I would imagine if it was on years it would have been a different story so don`t want 2 risk another one that`s going to crack.

Not sure how much the cracks are affecting boost as by the time the gasses are at the downpipe I think they`ve already passed the wastegate but it can`t be helping anything. The wastegate being loose at rest though I reckon may well be my problem then if it`s meant to be shut tight, so will sort it out and post back.

Thanks for checkin ur old turbo madmr2, I checked my actuator and it starts to move around 5-6 psi and is fully open by 11ish. I haven`t got any old pics of my old cars to check the actuator number on those. Did u replace ur turbo with another stock one ?

Will post back when everything`s sorted.

Thanks again!

Dom.

[madmr2man]

No problem mate, happy to help.

I switched my ct26 for a ct20b after the old one started dropping oil down the exhaust.
I fitted a BERK downpipe at the same time and honestly, I can't recommend these enough.
Build quality is fantastic and the presence of a flexi means no cracks.

[slipping clutch]

Blitz used to make a replacement elbow for the cat but its been years since I saw one come up for sale but you might get lucky with a bit of an internet search.

[Total Recall]

Well that wastegate was the reason for the late boosting. Mounted it a little further back and boost comes in at 2500 now, so I`m happy

Down pipe is welded up for now but will go for a Berk when i get another. That Blitz idea is good but I think looking now just fiting a downpipe is probably easiest - and easier to find!

Still boosts for longer than my prevous 2 cars, so maybe that`s just down to the downpipe. Other than that it feels just the same as those now.

I`ve even got the hairdrier noise back!

Thanks for all the help and info.

Cheers,

Dom.