Upgrading your stock turbo
Here we describe some common upgrades for your CT26 Turbo. There are a list of companies that do repairs, rebuilds, and upgrades. For questions and FAQ go to the Turbo FAQ.
See the Turbo Rebuild Page, if you dare.
Robert's Stage 0, is one of the *first* upgrades that should be done to your car. This is mostly for ST165 and ST185 owners. What you do is get a CT26 from a Supra Turbo, 87-92. Preferably as new as possible. These can be sourced for as little as 100 dollars, and a basic rebuild is cheap. If you have the money of course you should go for the bigger upgrade, but if you are on a budget this is perfect. Visit the FAQ for more information about the actual installation procedures. There are no horsepower numbers, but it basically makes your car more aggressive on the upper end without any negative fallbacks. If u are familiar with DSM then this would be like moving from a stock turbo to a 16g.
In terms of horsepower, say the stock turbo was good for 275 horsepower, then the supra would be good for 300 hp (on our cars) based on percentages, it's not that much bigger, but it will carry you further. If you are putting it on an ST185 you can bump that figure a little higher due to the response of the Twin Entry System. That would put you close to or above the power of the ST205 turbocharger.
This is the most common of upgrades that are offered by some of the companies below. The compressor is removed and replaced with a TO4 "B" compressor wheel. These are usually from Garrett or similar larger turbos. The B series is not the largest of the TO4 series, but significantly larger than the stock or supra turbo compressor. The compressor housing is bored out to match the size of the new compressor wheel. The exhaust side is left alone. This formula leads to a turbo that has very little lag if at all. Speaking in trim, that actual size of the compressor wheel, this would be a 46 or 50 trim. Generally these have a strong flow up to 20 psi and can be found as little as $350. An example picture is below.
This is the more aggresive of turbo upgrades. This is fitting a very large compressor wheel into the compressor housing. Usually this also involves modifying the exhaust wheel by clipping. Clipping the exhaust wheel is removing some of the material (at an angle) which will allow more exhaust to bypass the turbine in extreme conditions. The reason this is done is that when u are using your big upgraded turbo at a high psi and RPM, the exhaust cannot get out fast enough. So the clipping procedure will allow a little more flow at the expense of lag. The large compressor wheel also has it's share of lag, which most don't mind for the absolute kick in the pants it offers once spooled up. If you do go with this upgrade it is suggested that you upgraded your downpipe and exhaust system to help the turbo spool up earlier. This upgrade usually contains a TO4 "E" upgrade wheel. Speaking in trim this would 54 and 60. Some companies even offer a 60-1 wheel which is even larger. Most consider this overkill and would never operate at full potential. These turbos flow well at up to 25 psi, and are limited basically by the exhaust side. The usual price for this upgrade is $650, but you can find it for less at some companies. An example picture is below. Keep in mind that this a supra turbo, note that the supra compressor wheel is even bigger than an all trac. Also notice the clipped turbine on the bottom right picture. They also clean up your turbo nice.
By this point you should be considering changing to a different style of turbo. This would involve getting a new manifold or adapting your current one to suit the new style turbo. This also would involve a new downpipe and custom lines, etc. But for those who still wish to stick to their CT26, there are even further upgrades available. The next step in upgrading is changing the exhaust side (turbine) to a TO4 size wheel to match the compressor. The compressor is also upgraded to TO4 size with a large compressor wheel, or even the 60 series (bigger). The exhaust housing is modified or even replaced all together with a custom high flow housing. Turbonetics (below) offers this type of upgrade. They have a stock style exhaust housing that will mate to a garrett center section and still keep your stock compressor housing as well. Basically you are installing a new turbo, but it will still bolt to your current setup. This would require new oil and water lines of course. The extreme benefit is that u could go with a ball bearing center section. These types flow 30 psi and beyond and are in the 800-900 dollar range. Example below, notice the CT26 compressor housing, but the new different style exhaust housing.
How Big Is My Turbo?
Here are some comparison measurements.
Compressor Inducer - The inside part of the compressor, the part you "see"
Compressor Exducer - The total diameter of the compressor wheel, hidden behind the housing
Turbine Minor - The inside part of the exhaust wheel, the part you "see"
Turbine Major - The overall diameter of the turbine exhaust wheel, hidden inside the housing
|Turbo||Comp. Inducer||Comp. Exducer||Turbine Minor||Turbine Major|
|T3 - 45Trim||1.595"||2.367"|
|T3 - Super 60||1.90"||2.367|
|TO4B V Trim||2.18"||2.75"|
|T3 Stage 2 Turbine||-||-||2.122"||2.559"|
|T3 Stage 3 Turbine||-||-||2.229"||2.559"|
|T4 N Trim||-||-||2.071"||2.922"|
|T4 O Trim||-||-||2.296"||2.922"|
|T4 P Trim||-||-||2.544"||2.922"|
|T4 Q Trim||-||-||2.693"||3.111"|
MAJESTIC TURBO (USA)
Waco, TX 76701
Toll Free: 1 (800) 231-5566
Typical CT26 upgrade $450 w/ exchange.
Replacement turbos and upgrades.
Repair Service Upgrade
CT26 upgrades $450 special
T3/T4 turbo kits
They sell replacement CT26 with no core charge for $650.00
Replacement turbos and upgrades.
Tel: +44 (0)1202 487497
Fax: +44 (0) 1202 487467
Turbo upgrades and rebuilds.
Toll Free 1-866-4-TURBOS
CT26 Replacement Turbos, Housings, and Repair Kits
Here is a collection of CT26 pictures at several different angles. There are also pictures of different turbos compared to the CT26 so you can compare sizes. Thanks to Reg Reimer and Christopher Jensen for some of their pictures.