What is the benefit of going with a T04B vs the stock K26/8? I was going to have my k26/8 rebuilt or turned into a k27/8 or TO4B. It looks like the stock k26/8 will give pretty good performance? I am not looking for real big numbers. 300 RWHP at some future point would be more than enough..

Danno I see your post that:
"K26/8 @ 18psi = 270-280rwhp / 310-320lb•ft TQ (this is the limit of the stock injectors)"

270 RWHP with just the turbo and chip is about what I want to get for now. Then later if a MAP and injectors will boost me up to 300 RWHP + I see no reason to go with any turbo other than the stock k26/8?

Is there any other advantage with a going to a k27/8 or T04B that I am missing? The dyno's I have seen of the k26/8's seem to be pretty nice. And for the price of a rebuild of my stock turbo its hard to justify 15 or 20 extra hp?

I am running a k26/6 now, so peak hp and tq can only get better. The car does boost early, but I live in the city and cant really drive fast anyway. The times I do want power is on the highway or when I drive up in the mountains.
However I do know that replacing the turbo is a major pain. Will a T04B last longer than a k26/8? Is it really worth twice the cost for the performance gain?

 

I haven't seen a K26/8 above 18psi with our MAP kit yet. That's good for 310rwhp & 340lb•ft TQ. I suppose it can go higher than that since I've got a K26/6 @ 30psi.

"Will a T04B last longer than a k26/8? Is it really worth twice the cost for the performance gain?"

If you've already got a k26/8, I'd just rebuild it into a K27/8 and be done with it. As for performance, a K27/8 or TO4B is pretty much a wash. Here's a K27/8 @ 20psi that we dyno'd last weekend. Darn laptop I borrowed was incompatible with my chip-burner, so we couldn't do anything other than adjust fuel-pressure. But we did pick up +4hp & +25lb•ft by leaning it out 5% on the FPR though:



The mid-range is still way too rich beyond 10:1. So I think we can hit close to 400 lb•ft with better fuel-mapping next time.

 

WOW Danno. And that is with stock AFM?? or MAP??

I just re read your numbers about K26/8 with the new 18 psi chips:

this is me:

That same turbo K26/8 @18psi will be generating 265-280rwhp / 310-320lb•ft TQ

that is 330hp/375tq at the crank !!!!!

 

this is good info. I would like to stay with the KKK turbo if possible. Other than the piping to run the airfilter to the cold side of the turbo, is there any other fabrication that has to be done on the (turbo exhaust etc) going with a k27/8 vs a k26/8?
I am under the understanding that I will keep my hot side, center section and simply add the k27 cold site and internals? I will still remail oil/water cooled and there should be no problems with fitting the turbo under the manifold or making custom changes to anything other than the air take section?

I feel pretty confident that that dyno you posted did use a map and larger injectors to get 20psi. If so what size injectors did you run for that dyno?

Also in my case I am doing this in phases. I know you and I have spoke from time to time Danno regarding this, but just to be clear. I can run a k27/8 with a stock AFM but will have to drop the boost to below 14psi max? will I use the same k26/8 chip or have to get a new one burned?
Later I plan to get the MAP and Injector upgrade and at that point I will see the difference between the k27/8 and k26/8 right?

thanks,

 

Acually that car has an APE MAF which is why I have to burn a custom chip for it; no instant adjustability. Not that big a deal because once we have it dialed in, he's not going to change anything for a while.

"If so what size injectors did you run for that dyno?"

They were 52# injectors and they got maxed out around 5000rpm. We're gonna use a 928GTS pump to get more flow and turn up the pressure to extend the injectors a little. I'll just turn down the duty-cycle to get a little more overhead. Since this isn't a track car that will see extended 100% throttle, it'll be OK to max out the injectors occasionally.

"I am under the understanding that I will keep my hot side, center section and simply add the k27 cold site and internals? "

Yup., I'll send you an email on a place that specializes in KKK rebuilds.

"I can run a k27/8 with a stock AFM but will have to drop the boost to below 14psi max? will I use the same k26/8 chip or have to get a new one burned?"

I can get you a K27/8 chip easily. Actually, you can run 18psi with the stock AFM for about 270rwhp which is the max on teh stock injectors. With a MAP upgrade no more than 14psi at about the same HP rating. The difference between the K27/8 and K26/8 is more obvious at the higher boost levels, like 18-20psi. The torque drop on the K26/8 is more dramatic. But you'll need larger injectors to run that high.

 

Just a quick question danno, With shanes set-up is it possible to run 20lbs of boost with your GURU chips and 91 octane gas for the streets?

thanks ken

 

Danno, Thas a sweet setup. Especially since you can upgrade it in stages. And that dyno posted is awesome!

So, to make it in stages you would go like this:

1. Turbo and chips to match turbo. Keep stock air flow meter and injectors 270+ RWHP and less power loss at higher rpms compared tok26/8.

2. Install MAP and turn down the boost to 14 PSI on stock injectors (keep same 270 + RWHP. Probably boost a little earlier than the stock AFM too.

3. Get optimal injectors (55# or more. I guess we will have to see what you come up with here soon with your testing?) and a new chip to max out at around 350 RWHP or more! thats nice and pretty cheap if you add all the stages together. I guess we need to add some dyno time for each one to tweak it out.

To tell the truth, I am not sure I am ready to jump from my current setup which may be 230RWHP to another 100 plus HP! So for me it makes sense for me to upgrade in stages and get used to the power as I go. Plus its easier to budget this way! I know power is addictive, so I say this now, but I really though 300 RWHP and 330RWTQ would be more than enough for me. This setup allows that and the possibility for much more. The k26/8 route I was looking at would have saved me about 300$ for the turbo rebuild. But I would have had a 300RWHP (or around there) limit.


Let me ask this. What advantage if any would there be to run a k27/8 with the stock AFM new chip and larger injectors? Then do the Map later on?

Would you still be limited to the 270 or so rwhp or would you be able to get around 300rwhp with the stock AFM and everything else lilsted except the MAP?

 

OK, Danno...
I know that a MAF/MAP setup is the way to go, but just for the sake of curiosity - just how much HP can you make with a stock AFM? Within reason of course - say if you went to a K27, bumped the boost to optimum, with matching chips? For a setup like this would it be advantageous to go to a 55 lb injector or does the AFM set the "limit"?

BTW, I know we've done this offline, I just want to bump this thread...

 

I belive the stock AFM is the limiting factor and its about 256-275hp, been said once or twice i believe

 

Although the AFM limit flow and therefore HP it doesn't limit the absolute HP potential. But the turbo must be pushed harder to make up for the flow loss to attain the same HP level.

 

"With shanes set-up is it possible to run 20lbs of boost with your GURU chips and 91 octane gas for the streets?"

Sure, you'd just need to use the 2-degree retarded ignition setting. He's using no ignition retard because he's got a 96-octane mix.

"just how much HP can you make with a stock AFM?"

About as much as you want. Just that you'll force the turbo to work harder. K27 @ 18psi on AFM will be about 280-290rwhp. With a MAP upgrade, it'd be around 320-330rwhp at the same boost. Larger injectors would be needed in either case.

 

Thanks Danno.
You're up awfully early...

 

Thats what I was looking for.

So you can get a k27/8, chip set for it and larger injectors to get pretty darn close to 300RWHP(280 or 290) with the stock AFM.
or 270RWHP with stock AFM and stock injectors..... (300 to 400 bucks less)

Then add the MAP to wake up the low end and get that extra 40 or 50 hp! or perhaps more at higher boost!



This is good stuff... Now I have finally found the route I will take.

Danno,

Email me that list of vendors to send my old k26/8 to........

When I get the turbo sent off I will let you know so I can send you my old chip to be re-burned and decide on getting the larger injectors then or waiting until I go to a MAP.

thanks,


thanks,