Here is my Dyno sheet from last Month with ~12.5 lbs boost. Ralph from Groundzero did the tune. He recommended I come back at a later time with WA gas (Oregon is supposedly year round crappy).

I think the numbers are alright, what do you guys think?

Mods:
-Power FC with Banzai Adap. Kit
-Pineapple Rebuilt with Oil/Water Jacket Mods+Small Street Port
-550cc Prim/1000cc Sec.
-Full RB Exhaust
-Corksport FMIC
-Walbro 255
-Greddy Profec B
-Adjust. Fuel Reg.

 

This the stock turbo? What did he say about the dip in torque at 4500? Other than that i dont think there that bad. Hell your putting down 12 more ft lbs than me and im on a bnr stg. 4. I also am on 9lbs also though. Hows it feel on the street?

 

thats the first time ive seen a two-rotor make more torque than horsepower, but i guess it makes sense for a small stock turbo at 12psi, which probably ran out of steam real quick near redline.. nice numbers

 

It's a Hybrid- Rob with Pineapple has a guy who supplies the turbos. I wanted something quick spooling , so he went with what he called a "medium" compressor housing.

I honestly can't remember what he said about the dip in torque...
Ralph told me that my motor is capable of running more boost safely (max knock reading 10), but that I should have it tuned with a tank of WA State Gas since the gas in Oregon is so inferior.

The car pulls really hard- I've seen 105 kpa (15lbs?) stored as a max reading and it gets there quickly...Not sure if the difference in gas can be that great. I guess I'll find out when I have it re-tuned.

 

I find it odd that you made more torque than horsepower. The hp numbers seem spot on though.

 

Seemed hard to believe for me too...Ralph did say that in tuning the torque figure gets often overlooked in favor of bigger HP numbers, although it is actually more important. Once I swap the exhaust again and get the car through emissions in a few months (rats nest and everything else still there), I'll take it back to the Dyno and see how much more it will put down with a few more pounds of boost.

 

yeah hybrids should be good for 15-17psi

 

Something is wrong.
Torque (and HP) isn't supposed to drop off like that, especially with the big exhaust and ported motor.

What's the spec on the turbo?


-Ted

 

it's weird, the shape of the curve looks like it would be on a stock turbo, but the numbers are too high.

 

I don't know any details on the turbo- Rob has a turbo builder who supplied the turbo according to the performance level I was looking for but wasn't able to give me any detailed specs when I asked him. For what it's worth, I've been very happy with the spooling response, especially since the boost increase.

Ralph pointed out to me the opposite on the torque and power curves. He said that he looks specifically for them to drop off like that.
In order to give better answers I probably would have to talk with both Rob and Ralph again with pencil and paper handy... I'm pretty much a novice and with Rob and Ralph chatting a what seems a mile a minute I reach information overload quickly...

 

For comparison's sake, here are two dyno sheets: the first is a low mileage stock S4 T2 that somebody posted a while back, and I saved. The second is from an SAE paper on the s5 engines, which is measured in flywheel hp not wheel hp.

 

arghx- Thanks for posting those! comparing those with mine I now understand and agree with your first comment. The SAE one you've posted seems to have a similar drop off in both torque and power curves at a lower RPM just like mine.

The first one starts out with pretty much identical curves to mine although torque stays more even and power continues to climb at higher RPM.

Maybe my turbo does run out of steam, but if I understood Ralph correctly he believes that the motor and turbo is capable to safely make quite a bit more power with a few pounds of added boost... but I would need to return & retune with quality WA State gas in my tank...Oregon is now supposedly selling an inferior grade of blended gas- did a google search and here is what I found: http://www.das.state.or.us/ODA/news/071219ethanol.shtml

 

Normally, torque doesn't drop as fast versus the opposite end when it's climbing.
Having really high torque numbers also is a sign...
...that there's a restriction in the system.

If this is a hybrid, you should be fine, and I would blame too restrictive of an exhaust.
If this is an aftermarket turbo, your turbine A / R is too small.


-Ted