Promised the 3.8 dyno graph, here it is...

[Jeff Alton]

Hinted a few times in recent threads we posted about the 3.8 we were building. Here is the dyno plot. Very pleased. Notes about the build are in the chart...



Cheers

[flat6pilot]

Impressive numbers, Jeff! Were there pics of the engine I missed? What's this going in?

[RSstop]

Wow Jeff! Love the flat torque curve!
Question about the ported Heads: Were only intakes ported or did you also remove exhaust ceramic liners?

[Jeff Alton]

^^^ Ported was perhaps not the correct word. Blending of the guide boss and general clean up would have been more accurate. Liners are still in place.

Engine is in a 964.

In the pics you can see our 100% CF RS Style heater fan bypass tube made specifically to clear the ITBs. This tube is part of our Turn3 Autosport 100% Carbon line of products.






Cheers

[JoeMag]

What compression ratio?

[stownsen914]

Impressive numbers, especially for a streetable motor! It looks like hp is still climbing at 6500 when the graph stops?

[Geronimo]

I have always thought the more important number is the HP per $ and HP per LB, I think that is a great way to measure engines value/performance.

Either way this is a sick engine, that i'm sure it twice the cost of my entire 911 lol

[Jeff Alton]

^^^ This motor is not inexpensive. At some point the HP/$$ value starts to change. You can get a few HP for a few $$. A few more HP for a few more $$.

To get the sort of HP/Tq this motor makes it does cost. But, this motor (like all of our custom builds) is built with all of the best components. It costs between 40-65% of what some in the industry will charge, even though they largely use the same components. I would put the driveability of this motor (and all of the custom HP motors we build) up against any similar build and not be worried at all... Our low dollar helps keep the retail cost of the build down as well.

Cheers

[mikedsilva]

I want one.

[Jabate]

What lobe centers on the cam did you select and what compression ratio did you end up with on the 3.8

[Jeff Alton]

11.5:1 DR. Lobe centers are 113*.

[Jabate]

Thanks Jeff
Curious, are you running pump gas and if so, what obtained?
JA

[Jabate]

Octane?

[Jeff Alton]

91 Pump up here. However, here in BC we have a special blend of "low carbon" fuel which does effect power ratings. Many around here have proven using 92 from WA state will create a very noticeable bump in power on the dyno.

Cheers

[pkabush]

Gawd, I didn’t realize you guys had worse fuel up there than us. Amazes me that a lawn mower would run let alone a H.P. Porsche motor.
Super nice build btw. You must be happy with that torque curve. Or lack there of. Pretty darn flat.

[winders]

What size are the ITBs?

[K24madness]

What cams are you running? I am impressed by the flat upper torque curve. I’ve seen similar with VRAM but never thought you’d get there with ITB’s.

[Jeff Alton]

Cams are a DC24. We chose these after consulting with John (which we have been for years) to get a big wide torque curve/plateau. With all of these motors we want the throttle response and power the ITBs can make. But we want to chose a cam that doesn't make the motor a more typical ITB motor in terms of its power delivery. Cam choice, CR, displacement, exhaust all play into it. Then having an amazing tuning partner that can make the motor produce as much power as it can in all load/dynamic situations is key for us. Could we build a peaky version with higher HP? Sure, but that would not fit the requirements of this client.

Cheers

[Jeff Alton]

Originally Posted by winders

What size are the ITBs?

51mm tapered

[3rd_gear_Ted]

Just curious, what cooling set up gets rid of all the BTU's that +400 HP creates for the engine and tranny.