johntorg

I currently have a K26/8 and was wondering about the performance if I converted it to a K27/8? I also have a spare k26/6 that I could convert to a K26/7, if that makes more sense.

danny951

everything I've heard is that the k27/6 is a better way to go than a k27/8 because of the spoolup characteristics. I know that I am leaning toward upgrading to k27/6 and am still researching the options that are out there now for it. I am looking at upgrading the turbo and then probably going with the vitesse maf with his k27 chip board. (thanks gregeast and jgporsche for the info). I'm also still looking at the other maf options, but will probably go with the vitesse kit. From what I understand, I can do the turbo now and gain around 35HP and then upgrade to maf and gain some low end responsiveness as well as tuning ability to gain more HP from the new turbo with the ability to run more boost.

A question I still have is whether to upgrade an existing k26/6 turbo to a k27 compressor and housing or just buy a rebuilt k27 and sell the k26/6 to offset costs. I need to weigh the costs out, but I would guess buying a k27/6 and selling the stock turbo (since mine works just fine) would be the most cost-effective. Just something you too might consider, johntorg.

brad-cam

I just put a K27/8 on my 951 a few weeks back with Vitesse MAF and chipboard, and I'm pretty happy with the spoolup. There's 10 psi of boost by 3000 rpm and full boost by 3500 rpm or so. It's plenty quick and pulls like a freight train on the freeway. Use search to find the details. It dyno'd at 284rwhp - a low figure but I have a compression issue so it is not a true indication of the potential of the mods.

johntorg

Thanks for the input. This turbo is for my 2nd 951, which I just acquired. I will also probably go with Vitesse and have to decide whether to go with the MAF or keep the existing flapper. The car has a beautifully detailed engine compartment (see my Avatar) and I would like to keep it pretty stock looking. It currently makes 243 WHP with the K26/8 (although that was at 14.2 lbs of boost).

Selling the spare K26/6 may be a good option for me also. Does anyone have an idea of the prices for a used 26/6, the 26/8 to 27/8 conversion and a new/rebuilt 27/6 or 27/8.

gregeast

$600 + shipping from Turbo Performance to convert your K26/6 to a K27/6.

docwyte

Eh, if my current K26/8 blows up, I'll probably go with the Vitesse stage 2. Otherwise the k27/6 looks like a good option. Greg East and I are going to put our cars on the dyno soon. We basically have the same setups except I have a K26/8 and he has a K27/6. That way we can really see the difference in spoolup and hp/torque.

Mike1982

I have thought of this upgrade as well, K27/6 or the K27/8 option. I know all will say the K27/6 has good power plus you don't have lag but my car is just a weekend car and will be at the track end of this year and next year, so spool up isn't all that for me. If I could get 15psi by 3,600ish I would be happy with the car. Right now I have SMT-6, MAF (Vitesse with chips as well), 3 bar FPR, 3" testpipe, straight though muffler, high flow fuel pump, and some other odds and ends. When I get the next turbo, whatever size, I will upgrade to 55lb injectors or larger at the same time plus get my chips re-burned by John (Vitesse), wrap my headers to the turbo, then dyno the car and tune it. I would think that would be about the quickest the turbo could spool with everthing I have on my car. With a K27/6 I could get 15psi by about 3,000rpm and hopefully could get the 15psi on a K27/8 by 3,600-3,800rpm. I will have to do more research on the matter. Other major thing is cost, I know for $600 I could get my turbo (K26/6) turbo rebuilt to a K27/6 for $600 but what if I did decide to go to the K27/8 size, who sells those or what? With having a K26/6 size turbo, they couldn't use anything from my turbo, could they? So, I would be stuck with buying the turbo and selling mine.