Paulyy

28 i believe, pretty sure that's what he said in the first post? unless 28-28 means something else?

333pg333

Ahh yes. Didn't think of that with the 28-28. Must have meant 18-28. Just over 600whp on a favourable dyno with Jungle Juice at 28psi....it's possible I suppose. But I would have to think my current 2.5ltr motor to be quite a bit more sophisticated or modified than his and we saw 520whp at 26psi. Can't see us getting an extra 80whp with 1-2 extra psi.

V2Rocket

Patrick, what camshaft do you have in that thing?
ST said he had a big Milledge thumper.

refresh951

I have looked at hundreds of dynos and the bump in ST's dyno really is not explainable especially when looking at his mods. There would have to be a pretty big increase in VE around a narrow rpm band to result in what is shown. Mods push the power band lower or higher but I have not seen anything like what is shown here around a narrow band. If it were my dyno, I would want to see a repeat on the dyno to not believe it was some kind of error.

333pg333

Spencer, I doubt his cam was any bigger than the one in this motor.

2.5ltr
Longer custom Carrillo rods (approx 7mm)Still lighter than stock
Custom CP pistons with much smaller skirt and wrist pin (much lighter piston and assembly)
9:1 c/r
2.5ltr crank moderately lightened.
Huge ports with 49mm intake and 43.5mm ex valves
273 cfm @ 28 .550" lift Inlet (279 @ .600)
206 cfm @ 28 .550" lift Exh (211 @ .600)
Cam with .595 in / 526 exh
Solid lifters
Same turbo

V2Rocket

One thing just noticed - his run was corrected as "standard" vs the much more widely used/accepted "SAE"...the difference being different temperature/ambient pressure/humidity standards for the calculations.

SAE might read ~4% lower than "STD"....and in my own dyno runs of my 944, it can be a 5whp difference just by changing the drop down menu...and that's in the 120-130s whp range.

So if ST's run were corrected to SAE at -4%...he's at around 578rwhp.

333pg333

...then again...:-)

Paulyy

Patrick, you demonstrated how you can manipulate a dyno a while back... and got better numbers on paper.

Duke

The numbers does not really add up and the bump is hard to explain, even with a short massive boost spike. All this on 72 lbs injectors too? It is very very unlikely for this engine spec to exceed Patricks 2.5l in output per psi.

Fun fact. Normalizing the output in terms of boost and displacement this engine would be more efficient than my previous 3.0l 16v 968 9.5:1 CR turbo. Hard to believe..

reno808

That would explain that spike, Emma must have taken out too much timing to create heat for that t4 housing....

V2Rocket

maybe he stuck his "special tool" into the inlet

m42racer

Anyone who would accept an engine mapped like that, and posts it for consideration is nuts. They obliviously have no idea what they have or understand how the world works. Imagine driving that.

Maybe the nitrous went in a little too late.

Paulyy

he must have whispered Bob Norwood into his turbo prior

Dave W.

It could be wheelspin. He doesn't say if the Land/Sea dyno is a hub dyno or if it reads power from the tires, but I've seen many dyno runs when wheelspin occurs and his dyno chart has a similar pattern. The sharp spike at 5600 shows how much torque the tires can handle, that's where they break free. It looks like the tires start to regain grip at 6200 as torque goes upward.

It's either that, or it was designed to be a glory run. It's possible to withhold boost and timing early in the run to keep things cool and knock-free, then ramp up boost and timing at high rpm for a large surge in power. Obviously this is not a streetable powerband, but it looks great on the dyno.

Naplesguy06

Holy resurrection thread batman, STs uncanny power bump at 6500 rpm has people wondering.Lets ask tool he's around here somewhere.