Rebuilding The CT20A Turbos On JDM 6SPD TT

Hi guys,

After speaking to Turbo Dynamics, I've realised that replacing the stock ceramic turbos for UK ones is not as straight forward as I thought as the manifold and stud pattern is slightly different.

So I asked them for a quote to fully rebuild my current CT20A's and replace the ceramic part for steel.

They quoted me £1000 with me having to send my current tubbys off to them which I think is a good price.

Has anyone done this before?

I'm looking for close to 500bhp.

I think the best you'll get with hybrids is mid 400s, unless you go on a generous dyno. Why not replace your stock turbos with a second hand set (if they're damaged) and put the remaining money into a single fund?

I don't want a single turbo sorry as that means changing other things like injectors, getting the car mapped etc due to totally different power delivery depending on spec of turbo used. All sounds too expensive. Will mean I lose the nice low end pull too.

With my way, I still get the low end drivability (as it'll never ever see a track) and more power without the risk of blowing up my turbos if I increase the boost a little more and can use the standard ECU map if I stay around the 1.1bar mark until I have more funds for a proper ECU and a mapping session.

might be worth getting hold of paul whiffin at whifbitz think he does them! I would trust him more than turbo dynamics!

might be worth getting hold of paul whiffin at whifbitz think he does them! I would trust him more than turbo dynamics!

Tried him already but no reply when I called him. Will try again later.

Why not send a PM, he is online now.

See discussions on hybrids as the longevity questionability still applies. Essentially this is 'hybridising' the stock JDM turbos as you're putting wheels of different material into the housings.

Cheers,

Brian.

You're not going to get 500bhp without changing to a single or bigger twins etc.

You'll also struggle to get 450bhp without good supporting mods from hybrids.

I don't want a single turbo sorry as that means changing other things like injectors, getting the car mapped etc due to totally different power delivery depending on spec of turbo used. All sounds too expensive. Will mean I lose the nice low end pull too.

 

With my way, I still get the low end drivability (as it'll never ever see a track) and more power without the risk of blowing up my turbos if I increase the boost a little more and can use the standard ECU map if I stay around the 1.1bar mark until I have more funds for a proper ECU and a mapping session.

They are referred to as 'hybrid' turbos many members have them fitted. Max you will get from them is around 440-450hp flywheel at 1.4bar and you will be pushing the stock 440cc injectors beyond their limit at that sort of power.

Personally for the small hike in power at the cost of response I wouldn't bother.

Oh and with the right single turbo you don't lose 'low end drivability', my GT35R would make positive boost at around 2Krpm, only a couple hundred rpm more than the stock sequential turbos.

I don't want a single turbo sorry as that means changing other things like injectors, getting the car mapped etc

To get 500bhp out of hybrids you'd still need bigger injectors, cams, ECU, mapping.

I didn't say 500bhp exactly but as close to it as I can get from hybrids will do for me.

If it means 450bhp then so be it.

The car will probably be mapped once the hybrids are on. If the mapper says he can go further with bigger injectors then I'll fit them.

Also the single turbo kits on Whifbitz site are around £3k upwards and that's without factoring in supporting mods such as bigger injectors, mapping, etc.

You'll be limited to around 420hp on the stock 440cc injectors, if you want 450hp then you will need bigger injectors, ECU/mapping, cams.

https://www.speedforsale.com/supraparts/speed-sale-usdm-gt28-hybrid-stock-twin-turbo-upgrade-550rwhp-p-553.html

these have to give the best chance? but being from the USA you'd need (off the top of my head) a UK ECU, injectors and various downpipe/exhaust pieces plus a fuel fudger as an absolute minimum.........

You can get the JDM variations for $1700, that'd be my choice really.

http://www.speedforsale.com/supraparts/speed-sale-gt28-style-hybrid-stock-twin-turbo-upgrade-p-635.html

Indeed, I hadn't seen them i just stumbled on the first link via their ad on Ebay.com

Are they not CT12s?

I'll get bigger injectors and have it mapped but at a later date.

I'll see how the standard cams perform but I don't mind changing for better ones if required at a later date.

I just can't afford a single conversion but will look into the bigger hybrids.

Personally, I'd say ditch the hybrids, get some good stock ones from a member here, get a nice Side/Front Mount intercooler upgrade and mapping to control your boost. You'll get the most of your setup that way.

Your stock intercooler will be shot, after about 15 years of use.

You can also then pay £20 for your membership.

They state that you can run these at 26psi if i'm correct thats 1.7 bar. Would there be a heat problem with this size turbo at that boost? if not you should see great power at this boost.

Personally I would buy two new ones from Toyota. The problem with rebuilding turbos is they are now very old and many have cracked turbine housings. They CAN be welded but my experience shows they crack again, sooner rather than later. Between myself and two members here we have 10 + turbos, both UK and Jap spec, with cracked turbine housings. If you intend to keep the car consider buying a pair of new ceramics off Toyota. The cost of rebuilding yours WILL go up if they find the housings are cracked....

Personally I would buy two new ones from Toyota. The problem with rebuilding turbos is they are now very old and many have cracked turbine housings. They CAN be welded but my experience shows they crack again, sooner rather than later. Between myself and two members here we have 10 + turbos, both UK and Jap spec, with cracked turbine housings. If you intend to keep the car consider buying a pair of new ceramics off Toyota. The cost of rebuilding yours WILL go up if they find the housings are cracked....

I don't think I've seen a used turbo that hasn't had a crack in the housing.

I got the impression from the OP that the only reason for the swap was to gain more power. Gurnam are your current turbos working?

Yeah, I had my eyes on the Speed For Sale hybrids when I had my Supra. They look ideal for anyone who wants reliability, street drivability at a fairly decent price.

Arent brand new toyota twins like 3 grand or something stupid?!?

You will hate the lag on the larger hybrided ones - trust me!

Better go for JDM or a small single

I was talking to a member at a recent meet who had CR turbos refurb his J/spec ones for £600. This replaced all the seals and ceramic parts with steel. I've phoned them and confirmed this price is correct.

His turbos run perfectly BTW.

It's all well and good suggesting new turbos from toyota, but you're looking at 2k to replace both of them. 2k to me doesn't sound financially sound when replacing for stock units, if you're spending that amount of money you may want to look small single instead for a bit more money.

If the housings are cracked, then the best port IMO is to get some hybrids from Mr Whiffen, he can supply and fit the stage 1's for around £1500

Hybrids are rebuilt units based on your old cores. If they are cracked,. so will be the hybrids, probably welded up. Only option is to find cores to send for rebuilding as hybrids WITHOUT cracks, and good luck to you. I have managed to do this for an engine in build now, but it has cleared me out of good housings in the process.