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Stock hp & torque graph

Posted: Wed Sep 20, 2006 7:30 am
by Thomas Otten
Jake,

Would you happen to have a graph that shows HP and torque of a bone stock 1.8 or 2.0 engines, tested under your dyno? If not, how about a 1911? I thought it would be interesting to see what my 2056 kit will do in comparison to bone stock. Just as a reference.

Thomas Otten

Posted: Wed Sep 20, 2006 7:51 am
by MASSIVE TYPE IV
email me and I'll attach a graph of a bone stock US spec 914/2.0 engine.

Posted: Wed Sep 20, 2006 1:37 pm
by Thomas Otten
I was curious as to why the hp figures you show are at highest 86, which is a long way from the 100 hp that the DIN hp rating for that engine is. From a brief search on the web, I find that DIN hp is 98.6% of mechanical hp, but that isn't enough to make up the difference. Are Porsche's numbers based on running the engine with no "peripherals" like alternator, and perhaps even cooling fan?
I could see it if Detroit's numbers were based on engines with no peripherals (water pump, generator), that Germany would do the same, which for an air-cooled engine would entail removing the fan. Thoughts?

Posted: Wed Sep 20, 2006 1:53 pm
by Wally
Stock US spec engines do NOT have 100 Hp. 100 DIN Hp is the Euro spec version :wink:

Posted: Wed Sep 20, 2006 1:59 pm
by MASSIVE TYPE IV
Each stock engine was not dynoed...

The numbers that were advertised are very general while the dyno graph that I sent you was 100% from a tuned engine that was bone stock.

Dynos and engines both vary.All that matters is that both the stock engine and the engine that your kit was based from were tested on the same dyno, no matter what the actual numbers were the percentage of difference is all that matters!

Also, NEVER, EVER pay most of your attention to the peak HP number- the engine lives there on the street less than 2% of the time you are driving it! Pay attention to the torque curve and where the power is made- thats the real way to read a dyno chart!

Posted: Wed Sep 20, 2006 6:54 pm
by Bleyseng
Most I have ever seen from a bone stock 2.0L at Dyno days is 80hp. Thats a roller dyno so its rear wheel hp. Nice flat torque curve.

My old motor ran 95hp that day.

Posted: Thu Sep 21, 2006 5:39 am
by Thomas Otten
Ok, help me understand reading a dyno graph. Since you don't want to drive around redlineing your engine, and you really don't do that on the street when driving, you want to experience high torque (or hp since they are directly related) at the lower rpm ranges (2-4k)? Also, you want that torque curve to be basically flat, in that there are no humps. That way you don't get a flat spot when you are trying to accelerate and you haven't even gotten past 3k rpm. Reading a graph for peak hp, is not the full picture because it peaks at way high RPMs. Am I getting it?

Posted: Thu Sep 21, 2006 6:47 am
by MASSIVE TYPE IV
Yes, mostly..
Concentrate your focus of the graph where you drive the vehicle..

Always keep in mind that dynos run angines at wide open throttle at steady state, they can't measure acceleration and can't tell part throttle power or acceleration either.

Thats why many times an engine drives better or is faster than a dyno graph may lead it to be.

Dynos provide a basis to measure overall engine output and compare engines to each other. I mainly use mine for tuning and could care less about the power numbers, I tune for efficiency, good running temps and flat torque.

FYI- a dyno puts a load on an engine that a car never could, well unless you tried to tow a tractor trailer up pikes peak behind a VW. For this reason dips in the power curve generally can't be felt in the car, but they do lead to inefficiency at that RPM-