fejjj

Rebuilding k26/8 turbo.

Currently running:

A Tune
3 Bar FPR
80lb injectors
Stock AFM
E85

Street application

Thinking about going to k27/8

What say you guys?

Zeff

If you have to rebuild your turbo, I say go for it. It doesn't add too much additional cost and you already have supporting mods for fuel. You don't have the exhaust/wastegate mods to see the most out of the setup but you should see gains from the 26/8. If you open the exhaust and get a wastegate or at least shims you will see a night and day difference even with the 26/8. Even more gains if you go to the Mtune, but from there you'll need a bigger fuel pump for e85.

Aside from that, your spool up will be a little laggier than what your current setup is with a 27, make sure to get the 7200 compressor setup if you do go with it.

Dougs951S

Go k27/8, there is no comparison. The top end and upper midrange torque is way nastier with the k27 compressor. I love mine.

fejjj

How much laggier is it than the k26/8?

fejjj

When you say open the exhaust, do you mean deleting the cat?

Zeff

Post #3 from this thread:
https://rennlist.com/forums/944-turb...-k-27-8-a.html

"The lag to 15PSI between my 26/6 and the 26/8 was about 300 RPM. The lag from the 26/8 to the 27/8 was another 200 RPM. That said, lag was reduced by 300 RPM when I added the MAF. I did not have dyno data from the 26/6 to the 26/8, but the 26/8 put 280 to the wheels and the 27/8 put 305 (at 15psi). Before I get flamed, I use the Road Dyno (an ingition refrenced accelerometer, ala G-tech) to gather data along with my WBO2 logging. As the same unit and similar conditions were present, I can take the data with a good degree of confidence.

I don't know if the cost increase is worth 25HP, not to mention there are better spooling turbos for the money.



500 RPM can be substancial to some, minimal to others. For me, it works just fine."

Delete the cat or go full exhaust, many people will just go for a test pipe. I did that at first and saw big gains with a test pipe and Tial wastegate, but my car would max out just under 300rwhp. After going to a full 3-3.5" graduated exhaust, I got another 'seat of the pants' gain.

fejjj

Thank you for all the info!

Paulyy

https://rennlist.com/forums/9616181-post4.html

eman930

I'd do something different, since its a street car Id rock the 27/6, spools super fast and you'll have boost down low with grey power, perfect for back roads

User 52121

I will add this: don't think that the added lag will result in the car feeling slower. Sure, the car may take longer to make boost - but it will make more power off boost.

As Charlie from Evergreen explained to me, the stock K26 compressor housing is a restriction in itself. Going to the larger K27 opens up the intake path and flows more freely. So the power you lose by not having boost will be made up by more "N/A" power with the freer flowing intake path.

I went with a T04E on my car, which has a MUCH larger inlet (3" vs. 2.5") and the car makes a lot more grunt off-boost than it did before.

86 951 Driver

I would assume for this more found N/A power you need a MAF and other free flowing intake components.

User 52121

I suppose that's possible, depending on what's the bigger restriction - the K26 housing or the stock AFM.

Scott H

A K27/8 will outflow the stock AFM so unless you plan on running low boost (pointless with a K27) plan on upgrading to M-Tune or similar.

Voith

K27/6 vs K26/8

eman930

Man I wish I had a K27