New 260Z Engine - Dyno Results

[Ron Earp]

I just recently returned from picking up my new LNA Enterprises (Sam Neave) 260Z ITS motor. Sam has been working on the engine for awhile and I'm impressed with the results of his build.

He started with a junkyard 260Z engine I picked up from Rex Diffenbaugh and spent a lot of time investigating the various specific parts of the 260Z (carbs, cam, head, exhaust). A a good many modifications over the setup I previously had were made and I think the results are pretty strong. Shown below is the engine dyno of the motor:




And in the following graph I show the Dynojet rear wheel hp of my current motor (RW HP and RW TQ) versus the new LNA engine (FW HP and FW TQ). Clearly we're looking at different dynos - rear wheel verus engine dyno, plus differences in conditions. But even so, it is pretty easy to notice the large differences in shapes of the curves and it would appear the new LNA engine is going to end up with more area under the curve. Clearly much has been optimized with the LNA engine. Good stuff.




And, just for fun I applied a correction factor to bring the rear wheel hp results of my current engine (Adj RW HP and Adj RW TQ) up to close to the LNA motor (FW HP and FW TQ) to better compare differences in the shapes of the curves.


I'm hoping to get the new engine in the car over the next few weeks and maybe bring it down to Road Atlanta. If I can't make it down there it isn't likely to get involved in another SARRC race until the SIC.

[pballance]

Uh-oh, now if he can get the evil handling cured we need to look out!

Looks good Ron. Escalation in the arms race in Sediv ITS...........

[spawpoet]

Good stuff Ron. I haven't seen curves like that since Rio! That's a real nice jump in power from 3500-6000rpm. I imagine you are pretty happy with Sam's work. Did you have his header on there too?

[JeffYoung]

I ran your new numbers through lap sim, and it is obvious that your car needs another 2164 lbs.

I will let the ITAC know.

[spawpoet]

I ran your new numbers through lap sim, and it is obvious that your car needs another 2164 lbs.

I will let the ITAC know.

It's not hard to add that much weight back on to a z if you just patch the rust holes.

[lateapex911]

what were the correction cals Ron? And thanks for sharing.

[TomL]

Interesting numbers. Thanks.

Looks to me like the biggest change from your old motor is that Sam got rid of a hole in your torque and HP curves (5200-6000 rpm). If you hadn't had that, the old motor wasn't really that far off the new one - and probably ahead from about 5800- 6400. (assuming the FW/RW conversion is correct)

Did Sam mention anything specific on the carburetion that might account for the hole?

[Ron Earp]

Interesting numbers. Thanks.

Looks to me like the biggest change from your old motor is that Sam got rid of a hole in your torque and HP curves (5200-6000 rpm). If you hadn't had that, the old motor wasn't really that far off the new one - and probably ahead from about 5800- 6400. (assuming the FW/RW conversion is correct)

Did Sam mention anything specific on the carburetion that might account for the hole?

Not specifically but he did spend a lot of dyno time fooling with needles and needle shapes. Far more time than I had ever spent. I messed around with heights and dampener oil, but he was able to really focus on the proper height, shape, and so on.

What will be interesting is how the flywheel to rear wheel conversion goes. I know the dynojet we use is fairly repeatable. So I will dyno my old engine in a couple of weeks, hopefully on a Friday. Then swap over the weekend, and dyno the new one on Monday with, hopefully again, similar weather conditions.

I've got a feeling my old motor isn't better than Sam's from 5800-6400 though. The graph looks a bit odd in that region and it could be the correction factor needs to be lower, which would put my current motor at even more of a disadvantage.

Ron