K26/8 or K27/8?
04-18-2013, 07:09 PM
#16
Rennlist Member
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.
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.
The 26 compressor housing has more than enough internal flow area to feed a 2.5l 8 valve at sub 3,000 RPM.
And the inlet size, in front of the compressor, is really more there for fitment issues.
To the OP;
like somebody already said, you'll definitely need a MAF to go with the bigger compressor; otherwise sub-par results. So, you'll have to figure that in.
04-19-2013, 12:10 AM
#17
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Thread Starter
it's pretty much enough info there to tell you the difference.
04-19-2013, 03:14 AM
#19
Race Car
Join Date: Mar 2012
Location: Austin TX, drinking beer in the garage
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You do not NEED a MAF, though it will help squeeze the last ounce out of the k27 compressor. The k27 compressor wont flow enough air at lowish boost level (15-18 psi) to make more than 330-340 rwhp. It might see 360 rwhp at ~21 psi on a perfect day on E85 or race gas. In extreme cases it is capable of flowing close to 400 to the wheels, but that is at high boost and pushing it waaay out of its efficiency range. The stock AFM is capable of flowing ~325-330, and a good bit more with some porting. Even with the stock AFM you will notice a huge difference between the k27 and the k26 and as already noted, a slightly laggier turbo does not make a slower car. I get full 18 psi boost in 4th gear by ~3200 rpm and once it kicks in, I'll be flying past a k26/8 or k27/6 car. The extra power is worth it and you can always downshift to find the power. You can be cruising around town in 3rd gear, then drop it into 2nd, nail it, and get the car sideways.
Last edited by Dougs951S; 04-19-2013 at 03:52 AM.
04-19-2013, 06:31 PM
#20
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Thread Starter
Thank you Doug. I am leaning towards the k27/8 as I will be adding Rogues MAF to convert my A tune to M tune.
08-30-2014, 04:34 PM
#21
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k27-8 vs 27-6
Yep, k27-6 spools way faster , but down 30rwhp like we all expected
Lag was bad on 27-8 even with MAF & was ported head on friend 951
08-30-2014, 11:55 PM
#22
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Thread Starter
Throttle response with M tune and 3" turbo back exhaust is impressive.
Very happy with the K27/8 in this set up.
Very happy with the K27/8 in this set up.
