coldside hybrid stage 2 zero clearance

 

stock

 

Here is a dyno sheet from the 993tt I mentioned earlier. I do not have a copy of the final dyno sheet since I gave it to my customer, however, I have this one which is close, but still a work in progress as indicated by the "tal_first_runs" filename. It is the first sets of runs while adjusting the final fuel settings, but not with the timing optimized which accounts for the displayed 421hp, and not the final 430hp.

This was produced on an 4WD Dynapack dyno and I have found that the drivetrain loss is about 22% when compared to an engine dyno in my testing of various engines.

Also, by the look of the dyno sheet, you can see the wastegates open at about 3300 indicating .7bar was achieved. I would not use this as representative of where the boost actually comes on. The dyno tests were conducted using 12 second runs between 2500 and 6500 and is not representative of the load that can be achieved on the road. The MoTeC logging of a test drive shows .7bar of boost is achieved at 3100rpm.

 

Pram and Geoffrey, thanks for posting the info.. Guys, as Bill has stated the K24's will get walked on.. If you look at Prams turbine housing you will notice the amount of metal that has been removed.. Lets say that the profile is very similar to the K24 casting for flow, with one exception!! A smaller A/R and a turbine wheel that will utilize all the porting and added heat/energy.. Of course all the customers have ported and polished there headers, I think that Pram is doing that as we speak.. In fact I think thery are in his wifes dish washer!

 

Thanks Pram. Here's a comparison between stock, Kevin's hybrids and the Ruf Turbo R. Any comments on the differences?

 

TB.

I am with you on that. I exchanged several PM's with Kavin about his conversion and decided that the lag is not so bad on my K24's after-all and I really like the tremendous pull they give at about 3200 rpm. The fact of the matter is that with K16 Hybrids will gain low end faster spool up (not much!) but loose HP at top end.

In any event when one runs into a compatible car to let it all out on local hwy, it is hard to stay under 3000rpm and worry about the lag!!!. I am yet to find anybody that competed on track or hwy on low rpm (that would take all day )

Regards,

 

gooseNSJ4, you are right on. The bottom line is how you drive. If I raced you on the highway with my Ruf and K16 hybrids, you would probably pull ahead over 150 MPH or so. However, if we were on a mountain road, you would be frustrated trying to keep up because of the delay between stepping on the accelerator and the engine responding.

Also, if I raced you from a dead stop, I would guess I would be ahead until we reached 120 MPH or more. In other words, don't race a stock Viper from a dead stop to 100 MPH. He'll probably be ahead the whole time. With the K16's, you'll be ahead from the start.

 

K24s fall off somewhere between 525 and 550hp. The K16 hybrids will outflow them any day and will do it with less lag. They are more efficient turbos, ZC or not.

 

Geoffrey,

Like Kavin said, the K16 Hybrids will run out of air at high end, so I am not sure if the hybirds would even get to 525 or 550hp. So I would probably agree that the K 16 hybirds are a more efficient turbos, but depending how or where you use them.

Regards,

 

Kevin did not say that the K16s HYBRIDS run out of air at the high end. That is the point of the hybrids, they have the engine of the smaller k16s (turbine) combined with a LARGER than k24 compressor depending on what stage you choose. Stock K16s for sure do and are good for maybe 500hp.

 

Bill,

I agree, with one exception, I was fortunate to take on a Viper from stand still with stock K-16 and the K-24 on separate occasions. Both times I admired the Vipers hood embalmment in my rear view mirror, again maybe the drivers wear out of State, but the difference with K-24 was that I was able to gain ahead easier then with K-16. All this is really confusing, all I know that no matter what or how it happens I enjoy driving my TT on beautiful sunny day! If you can please, PM me about your Ruf turbos, my specs., are as such in the profile, do you think I would have to reprogram my ECU.

Thanks,

Goose.

 

The RUF Turbo R looks like it has a clipped turbine wheel. Kevin, is that a clipped wheel?

 

Thanks everyone for your reponses!
Kevin is the man on the turbo front!

The one thing I don't like based on the dyno sheets of the hybrids is that peak HP is so low (approx 5,200). Granted that they spool quickly but seem to run out of air up top. This is most likely due to restrictions in the exhaust side of the turbo. I would agree this is probally the best turbo for most but not all.

I want both quick spool and great top end. After further research I plan to have Kevin do my K24's. I will address the lag issues in other ways. I plan to have the hot side ceramic coated and muffler bypass mod to minimize the lag. Granted on a tight track the hybrid still may have an edge but not were its important to me in the 5-7k rowing.

Great thread overall!

 

Geoffrey,

 

Yes, exactly what I said, the stock k16, not the hybrids fall off. This is a function of the stock k16 compressor wheel, not the turbine wheel which is reused in the hybrid turbo along with a new larger/more efficient compressor wheel.