Cobb Tuning dyno pull

[blu_]

Originally Posted by Jeff Lange

EDIT: I am wrong. Interesting that they would want 93, I've never seen anything from Toyota require 93.

Jeff

All Subaru's that require premium are like this. In the end it doesn't really matter IMO and never really affected my timing on the STI. It's a fine print thing that nobody really cares about, nobody who is running a stock map a tleast.

[dsgerbc]

Originally Posted by blu_

All Subaru's that require premium are like this. In the end it doesn't really matter IMO and never really affected my timing on the STI. It's a fine print thing that nobody really cares about, nobody who is running a stock map a tleast.

Nope. My manual specifically mentions that the engine is designed to run on 91. No references to 93 whatsoever. No idea what STI manual says. BRZ says 93, and 91 is acceptable with no drivability and reliability issues (read: with less performance).

[blu_]

My STI manual stated 93. I thought my old legacy manual stated the same.

[dsgerbc]

Here, says 93 for STI, with lower performance on 91. 91 for the rest.

[PERRIN_Jeff]

Originally Posted by Turbowned

I'm shocked nobody's mentioned it yet but:

WHAT KIND OF DYNO ARE THEY USING?

That makes a bit of difference when you compare it to other people's dynos. Also the altitude/air density would be useful to know, too.

They have a Mustang dyno which is great test as they read a bit low.

Those lucky dogs! So Jealous!

[blu_]

I take it you guys have some parts in development?


edit: I just realized that's the same car I sat in two days ago lol

[PERRIN_Jeff]

Now why would we do that.....

I see how some people complain about the power, but 160-ish is right were it should be. Also like some I see room for improvement, which is exciting to see. When is that AccessPORT going to be ready!

[Jordo!]

Originally Posted by Draco-REX

Pig rich? Pig rich is 9:1...:P As it is, you want mid 12s for power.

As for the dropoff, there's speculation that the throttle plate begins to close near redline to reduce strain on the engine. That would also explain the richening of the AFR. I wish someone would log the throttle plate.

For an N/A motor -- even a high strung one -- 11's approaching fuel cut is very rich. High 12's or low 13's generally make better torque, but on this particular motor with high compression pistons and DI who knows?

When you are 9:1 or less, we're generally talking potential cylinder wash territory -- well beyond what I think of as "pig rich".

I bet it can be leaned out a bit safely, and make better torque, especially if run on 93 instead of 91.

Originally Posted by Draco-REX

200/151 is at the flywheel. The 164/142 is at the wheels. It takes power to turn the driveline (gears, driveshaft, rear diff, axles, wheels) so wheel hp is always lower. In this case it's about 18%, but this might be a low-reading dyno.

I'd like to see the damn thing on a dynojet already... load bearing dynos generally have too many fudge factors to know if it's reading "high" or "low".

[dsgerbc]

Aaaaand, the video is now private. Hope they'll re-run it with 93

[Oriental Life]

If you wonder about my comment earlier - here is a decent dyno:

same here

Look at the rollers diameter and compare it with these 10 inch rollers used in this test. Its nothing like real life surface. You need larger rollers for accurate results (minus additional strain it takes to keep the car on these small ones).

Really, that's a poormans_dyno test.

[TheRipler]

I can't see the video, so I don't know what happened. I can only comment on the comments.

Originally Posted by GED68

I though Subaru showed these numbers 200/151...At flywheel? vs 164/142 real world?

Originally Posted by tranzformer

That looks like it says 190-some hp to me. Maybe it says 200. *shrug*

The torque dip in the mid-range is where Subaru typically pulls back peak torque of the motor. This is the spot where you are most likely to see knock, so they back it off a bit there to keep everything happy for long life.

IIRC, the dyno is indeed a Mustang AWD with mechanical linkage between the rollers. The mechanical linkage is much gentler on center differentials for AWD cars, and is preferred for most Subarus. Not really an advantage in this case, and Mustangs are known for heart breaker numbers anyway (vs internet numbers on other dynos).

Wish I could have seen the AFRs before the video was pulled.

[dsgerbc]

Originally Posted by TheRipler

Wish I could have seen the AFRs before the video was pulled.

Post #23

[TheRipler]

Originally Posted by Oriental Life

If you wonder about my comment earlier - here is a decent dyno:

same here

Look at the rollers diameter and compare it with these 10 inch rollers used in this test. Its nothing like real life surface. You need larger rollers for accurate results (minus additional strain it takes to keep the car on these small ones).

Really, that's a poormans_dyno test.

The first dyno you linked is an inertial dyno, and you have to have the big rollers because that's where all the load is coming from. The second link is a Mustang dyno, and it generates a load using electromagnets. The size of the rollers isn't all that important for those.

Inertial dynos are great for WOT pulls, but load bearing dynos are generally better for tuning out the rest of an EFI map. Drag cars and carbed motors don't really benefit from the extra expense of the load bearing dyno, so the old school hot rodders will usually say inertial is better.

Originally Posted by dsgerbc

Post #23

Thanks, I missed that line. Doesn't look to bad for stock, given emissions and whatnot.

[NESW20]

if you want to post dyno numbers on an MR2 forum i frequent, you had better post dynojet numbers, as they are apparently the most consistent from dyno location to dyno location. if you post dyno graphs from another dyno, people will look at the curve but disregard any numbers listed on it.

the horsepower number of ~160whp was pretty well within the range i was expecting to see. i was not, however, expecting 142wtq. what gear did they do the pull in?