Today I spoke to a company that refurb and upgrade turbos and they reckon that they can refurb the K04 Cupra turbo and include a new thrust bearing for better reliability and shorten the shaft and modify the fins for better spool and top end power through ability to run slightly higher boost.
I also spoke to the company that used the modified turbo with the cut back shaft and modified fins on an S3 and they report better/harder spool, but they are going to suggest that the fins be more OEM like for the next version so that the top end power is better - they felt it weakened off at the top end.
Power / torque figures still to be confirmed, but it looks like there is more to be had from the Cupra using the stock hardware with a few tweaks and tucks. There is an uprated manifold being designed for the K04 turbo at the moment also.
Obviously, a custom map would be required to take advantage of this. Power/torque curves from the upgraded turbo have still to be done due to a lack of a 4 wheel drive rolling road where the work was done.
For those who are interested, in the event of issues, provided you can get the turbo off your car, it can be overhauled and upgraded if you make it available to this company for 3 days where 2 days are postage and 1 day is work done.
Basic refurb £295 + £20 + VAT
As above with uprated thrust £395 + £20 + VAT
As above with thrust and Cut back shaft £495 + £20 + VAT
The £20 is for pick up from you and delivery back to you.
Also, at the moment, the OEM turbo already has the largest wheels available in the K04 range, and, combined with the difficulty in holding and machining the compressor cover for a larger wheel, this means the only practical action for greater increase in power means changing turbo altogether. For now, there are no plans for designing a hybrid.
Therefore the OEM turbo does seem to be a good piece of kit, and up there size wize with the GT28 unit often used on the 1.8T engines.
Hope this helps/is of interest.
Horace
I also spoke to the company that used the modified turbo with the cut back shaft and modified fins on an S3 and they report better/harder spool, but they are going to suggest that the fins be more OEM like for the next version so that the top end power is better - they felt it weakened off at the top end.
Power / torque figures still to be confirmed, but it looks like there is more to be had from the Cupra using the stock hardware with a few tweaks and tucks. There is an uprated manifold being designed for the K04 turbo at the moment also.
Obviously, a custom map would be required to take advantage of this. Power/torque curves from the upgraded turbo have still to be done due to a lack of a 4 wheel drive rolling road where the work was done.
For those who are interested, in the event of issues, provided you can get the turbo off your car, it can be overhauled and upgraded if you make it available to this company for 3 days where 2 days are postage and 1 day is work done.
Basic refurb £295 + £20 + VAT
As above with uprated thrust £395 + £20 + VAT
As above with thrust and Cut back shaft £495 + £20 + VAT
The £20 is for pick up from you and delivery back to you.
Also, at the moment, the OEM turbo already has the largest wheels available in the K04 range, and, combined with the difficulty in holding and machining the compressor cover for a larger wheel, this means the only practical action for greater increase in power means changing turbo altogether. For now, there are no plans for designing a hybrid.
Therefore the OEM turbo does seem to be a good piece of kit, and up there size wize with the GT28 unit often used on the 1.8T engines.
Hope this helps/is of interest.
Horace
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