I'm in the process of researching a turbo upgrade for my '86 951. What direct bolt on turbos (quick spool design) are available. I'm looking for increased spool-up speed in conjunction with a 400-450 HP (at the crank). I already have upgrades to support the extra power, my next step is the turbo itself. Any experience with the Speed Force Racing Stage2/3 or the Kokeln upgrades. What about the Garrett T04?

 

If I'm not mistaken both the Kokeln and Speedforce turbos are Garrett T04's.

 

I should see 400 at the crank with my K27/8 with all the goodies and 18-20psi.

Direct bolt in application, lag is closw to a K26/8.

I'd do some looking into on that, personally.

If 450hp is the goal, you need bigger, and there you run into lag (as you know) and also fitment since large turbos hit the stock manifold.

 

Good luck on the search for a quick-spool turbo that can flow enough to generate 400hp...

 

Make sure you get a ball bearing T-04, then you will be close......#8 hot.

 

We need one of those IHI turbos with Inconel turbine blades, composite compressor wheels, ceramic ball-bearings and a beryllium axle!!!

That just reminded me of something... wonder how long it will be until someone comes out with a mag-lev bearing for turbos, eh? Now we can really talk about some serious BOOST!!!!

 

Hey

The K27/6 will spool up much sooner than a K26/8 turbo. From every dyno run I've done, and after reviewing a lot of other runs, I've seen the peak TQ come in at least 500 rpms sooner with the K27/6.

The TQ peak, and more specifically, where the TQ peak comes in at, is almost identical between a K26/6 and a K27/6.

The S turbo simply has a hot side that's way too big for a stock 2.5L engine.


Further, the K27/6 turbo can easily make 330HP-340HP to the wheels without running more than 18psi-19psi boost on a 2.5L engine. (A K26/8 will never make that kind of power.)

To get more than that, you'll be running gas better than what you can get out of a pump, and you'll be running at least 20psi boost.

I've seen a some example dyno sheets where the TQ was higher, and the owner swore up and down that they were only running 17psi-18psi boost... but upon further exammination, they were experiencing boost spikes of over 20psi boost at their TQ peak.


Here's a url to my site (www.tonygarcia.org) that has some dyno comparisons (I've got a ton more that I never got around to putting up on that site).

<a href="http://www.tonygarcia.org/dyno.htm" target="_blank">http://www.tonygarcia.org/dyno.htm</a>


TonyG


Posted by Paul:
I should see 400 at the crank with my K27/8 with all the goodies and 18-20psi.
Direct bolt in application, lag is closw to a K26/8.

I'd do some looking into on that, personally.

If 450hp is the goal, you need bigger, and there you run into lag (as you know) and also fitment since large turbos hit the stock manifold.

 

 

 

Do you have a K27#8 to compare to the K27#6? Also how about a K26#8 and a K27#8 that might put it in a logical perspective for me : )
Paul

 

I wouls like to see that comparison as well. If HP and TQ is about the same between the K27/6 and K27/8 I may have to change the hot side.

Paul.. what did you end up running? (turbo and power)

 

When you say the Garrets are T04s, surely that isn't enough info to go to the turbo shop with, right?

I mean, I can't go to the turbo rebuilder here and say "make my k26/6 into a T04, can I? Don't you need more info, trim, etc?

What exactly would be the Garrett turbo that is the best competitor for the K27/6 on our cars? (with the object being less lag, more power than the k26/6...)

Like I said, there is a turbo rebuilder here, so...

 

Additionally, how would you supply fuel for the k27/6? Increase fuel pressure? Chips? what is everyone else doing, running 26/8 chipsets?

 

Custom chips, adjustible FPR, bigger injectors (possibly) and a MAF with a fuel controller.

That will cover your bases.

You can do it with chips and AFPR, but get it on a dyno to tune it, so you are sure you don't go lean.

 

lou,
for sure Danno is right about 450hp and a quicker spool-up than a k26/6 being mutually exclusive goals, but you can get a turbo to support significantly more hp and not lose too much as far as quick spool-up goes. I'd encourage you to call Jason at TEC. He matches turbos to applications for a living and does a good job at it. The T04E variant he set me up with supports 440 hp and I've got 12 psi @ 3200-3400rpm.

keith,
I'd encourage you to call Jason as well.
And as far as managing fuel, etc. I hate to sound like a broken record BUT, about $1000.00 worth of programmable engine management hardware will allow you to accomplish your goals more accurately and easily than $2500 worth of MAF/controller, custom chips, AFPR, etc.