ct26 with 62mm trim

[Nick Bryant]

Has anybody got or used one of these they are supposed to rated over 400 bhp

[Mark Edwards]

I have no doubt that it will make the power, but it will heat up very quickly. Really not worth it TBH. I'm at the point of producing to much heat on my ct26 now and thats at 364bhp.

[MR2Mania]

It really frustrates me when people think that "trim" means the diameter of the compressor wheel (not you, Nick - the site advertising that).

The correct definition of "trim" is (quote from Garrett site):
"Trim is a term to express the relationship between the inducer* and exducer* of both turbine and compressor wheels. More accurately, it is an area ratio. "

And here's how to calculate it:

[MR2Mania]

Having run a very special hybrid CT26 for some time now, I'd say you *can* squeeze up to 400bhp from one.

But if you want to go beyond 400bhp in this day and age of turbo technology, and for the expense of such a hybrid turbo done properly, I'd much rather go for a decent Garrett spec, and preferably with an external wastegate.

[Nick Bryant]

Well the only reason i ask is that ive been offered one for £450 delivered to my door and im on a bit of a tight budget after paying for an engine rebuild and lots of other little bits and bobs but i dont think ill bother now
cheers for guidance

[Spidey]

I too was looking at a similar turbo ( and neither do i understand all the tech terms) but it was labelled "60-1"

http://cgi.ebay.com/ebaymotors/Toyota-S ... enameZWD2V

Any chance someone could mail him (his email is [email protected] )and ask him techhie q's and find out if this will/can do what he says it can?

Am I right in saying that the reason it's producing so much heat is because of the high boost it's running at ? So, if I ran it at lower boost to aim for 350rwhp ( with supporting mods etc), it may be an option for someone on a budget ?

TIA
Rob

[Spidey]

Also, turboTechnics also do a Hybrid turbo - think they had

Stage1 - up to 380hp - £650 + core
Stage2 - up to 500hp - £765 + core.

I know it's asking a lot but if someone in the know could ring and check the tech side of things and if they will have same heating problem etc ?

P.S. My angle was same as Nick - I'm on a budget and keeping the CT26/20-b housing allows me to avoid expense of new downpipe, oil lines, brackets, manifolds etc

TIA
Rob

[Mark Edwards]

Also, turboTechnics also do a Hybrid turbo - think they had

Stage1 - up to 380hp - £650 + core
Stage2 - up to 500hp - £765 + core.

I know it's asking a lot but if someone in the know could ring and check the tech side of things and if they will have same heating problem etc ?

P.S. My angle was same as Nick - I'm on a budget and keeping the CT26/20-b housing allows me to avoid expense of new downpipe, oil lines, brackets, manifolds etc

TIA
Rob

I have to turbo technics stage one giving me 364fwhp at 1.6bar. It's a great turbo for short bursts and it's been brilliant for what i've wanted up to now. But after sustained boost the intake temps go up to unacceptable levels.

[Spidey]

Thanks for that Mark.

I'm assuming then that if I got the stage2 from TurboTechnics and as it is rated up to 500hp, that if my end goal was around the 400 mark, that it would be running at less than it's max boost and hopefully not run too hot ?
Apart from the stage2 from TT, I can't seem to find a turbo (hybrid or otherwise) that will give you400-450hp, at that price.

www.nengun.com do have cheap turbos but I wouldn't be very sure on specs etc.

Anyway, my end goal of 400 might be a yaer or two down the road. At the moment, I haven't upgraded internals, so TT stage1 might be an option for me for the next year or so.

Thanks again fro your help
Rob

[Spidey]

P.S. when you say about temps getting too hot. Are you worried about actual temp or the turbo or intake temps ?

If it's the intake temps, surely upgraded intercooling/chargecooling and WI will sort that ?

As I said, I'm new here - so, just let me know if I'm way off the mark in anything I say !

Thanks
Rob

[Mark Edwards]

I already have incredible cooling so that won't solve the issue. The problem with the ct26 is the exhaust housing, it's quite restrictive at these levels and it won't matter what stage you go for, it'll always be a problem. All of the ct hybrids change the intake but there's very little that can be done to change the exhaust side.

If you want 400bhp, you need to be looking at a completely different turbo and not a hybrid.

[Mark Edwards]

You will get 400bhp from a hybrid of course, but the intake temps will be ridiculous.

[Spidey]

Thanks for that Mark.

Due to cash restrictions, I think I may go for go for hybrid with a 320-340hp goal in mind and then come back and look at a bigger Garrett or HKS turbo in a year or so.

Thanks
Rob

[Mark Edwards]

The cost difference isn't that great tbh, i wish i'd gone straight for the garrett to start with.

[Spidey]

Another thing - can you roughly equate a Garrett turbo family to a power band ? i.e gt28 - up to xxx hp ? gt30 etc

If so, which family or specific turbo would you need for the eventual 400hp mark ?

Nengun have great prices but you, of course risk getting hit with Duty when they arrive.

Thanks
Rob

[Mark Edwards]

http://www.turbobygarrett.com/

I'm going for the GT2871R, running at 1.7 - 1.8bar, should see me just over 400fwhp.

[MR2Mania]

OK, here's *my* take on it, so read carefully if this is the route you're considering...

Hybrid CT26s can be good, but they're NOT going to automatically change the laws of physics. Yes, you can get a hybrid to 400bhp, but you won't reliably get above this. It's NOT just a matter of the stock turbine housing, which seems to be a restriction, it's to do with the type of wastegate it runs, but I'll come back to that in a sec.

On *my* CT26, I have a pretty big compressor wheel (Garrett - in theory, good for over 400bhp), and a clipped turbine wheel. Dave Rowe seems to reckon that mine is breaking 400bhp already, but I'm not so convinced myself. I'm running 1.6bar.

Now, my intake temps are good initially (the ST205CC with bespoke front rad seem to be doing well to cool temps for a couple of high boost runs), but when I cane it for some time (as you'd see on a track day), the intake temps will eventually rise to just above 60C on a hot day. I *think* the CC system is finally getting heat-soaked here, and the temps *may* not rise above this point, but I'm not sure because I've not taken it out for a full trackday session to be 100%.

Now, the reason that this is happening is because the heat put IN to the CC system's water is more than is being taken out by the front rad. Since I'm monitoring temps absolutely everywhere, I can see that the raw temps coming out of the turbo are excessively high (ie they're exceeding the limit of the air temp sensor which is 150C!!), so it's no wonder that the CC system is struggling to cool when on sustained boost for a long time. Now, knowing what the efficiency of my compressor wheel should be like from seeing the compressor map for it, I shouldn't be exceeding 150C after the turbo. Therefore, I'm making the assumption that something else is causing the high temps, and my money was on the the CT26 turbine housing - it's already been discussed before that the Achilles heel of the CT26 turbine housing is the flow through the wastegate ports. Despite having a clipped turbine wheel (which should help the situation, as it'll flow better at higher revs), it still happens. Now, Mark Edwards is running a TT hybrid CT26 with a different turbine housing, which is supposed to get over the known problem with the CT26's wastegate ports, and he must have a similar compressor wheel to mine. However, he too is witnessing his final intake temps getting too high (higher than mine!) after just doing one top speed run. Part of this is that he's using the Cinque rad which is not as efficient as mine, but I too think that his post turbo temps must be excessively high. So, basically, it seems there are problems with running too much boost through ANY CT26 hybrid, whether with the same turbine housing or not.

Now, going back to the issue of trying to get over 400fwhp. When at Owens, we were conducting tests with various different Garrett DBB turbo specs on Owen's test Evo8 on behalf of Garrett. We all know that the Evo doesn't have intercooling problems as there are plenty running 500fwhp on the stock IC, so why is it that we struggled to get over 400fwhp, even though the compressor maps say we should do it. We tried various different configs on the exhaust side, and we got some improvements, but at the expense of lag and a shortened powerband, so this wasn't exactly a solution.

The conclusion we all came to is that you can't easily get more than 400fwhp from ANY turbo with an internal wastegate on a 2 litre engine.

This is why I say that, if you want in excess of 400fwhp, don't waste your time - go STRAIGHT to an external wastegate setup. DON'T try and convert an internal wastegate turbo to an external wastegate, because it can never be as efficient as one that is designed to be externally gated from the start.

I hope this makes sense, because it'll save you a LOT of time and money...

[MR2Mania]

Oh, and another expense to possibly factor in is a set of decent cams if you want to go over 400fwhp, especially considering that the Rev1/2 cams are lower lift and duration than the stock Rev3 ones.

[Spidey]

Thanks, lads.

Basically, you're saying - Size Matters ! But what I didn't fully follow was your conclusion about the external wastegate ? I'm not a turbo tecchie but is the advantage of the external wastegate that it leaves more room for a bigger housing ?

Also, what do you think of this for a relatively cost-effective upgrade ?

http://cgi.ebay.com/ebaymotors/Bolt-on- ... QQtcZphoto

[Fats]

How about this, i never fitted it, had an unfortunate accident. I was going to have it check and serviced but now i have a change of plans, going for a TD06 on a rev3. the hybrid is for sale