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:


http://www.gt40s.com/images/Z/260Zenginedynojun2009.jpg

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.

http://www.gt40s.com/images/Z/260Zenginedynojun2009compare.jpg


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.
http://www.gt40s.com/images/Z/260Zenginedynojun2009comparecorr.jpg

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.:D

[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

[quadzjr]

How much is all this dyno time costing you? sounds like a professional setup with money to spare going on over there :D

[seckerich]

How much is all this dyno time costing you? sounds like a professional setup with money to spare going on over there :D


Welcome to ITS in the Southeast. Most front runners are all out pro quality builds. Except T- Dub.

[Ron Earp]

How much is all this dyno time costing you? sounds like a professional setup with money to spare going on over there :D

Definitely no money to spare now! :o

Steve would know what it takes to run upfront in ITS since he does that on a regular basis. I'm not to that point yet, driver or car, and it has been a long road to get as far as I have.

But I think it safe to say the SE ITS division is probably the strongest in the country. Some serious effort being put forth.

[JeffYoung]

And look at the diversity: 260z, 240z, 280z, 280zx, BMW 323, E30 325, Miata, RX7, 944S, TR8, 190E, GSR, Prelude.

[Mazmarc63]

Welcome to ITS in the Southeast. Most front runners are all out pro quality builds. Except T- Dub.

And me.:shrug:

http://www.mylaps.com/results/showrun.jsp?id=1171610

http://www.mylaps.com/results/showrun.jsp?id=1171611

:happy204:

Nice numbers Ron. Sounds like alot of work.

And the Mazda goes Hummmmmmm:D

[xr4racer]

I sure hope Ira's car in the new Grassroots was on a very optimistic dyno 183 hp and 167 ft-lbs!!! That kind of power at 2380 lbs is very hard to beat.

matt

[lateapex911]

I sure hope Ira's car in the new Grassroots was on a very optimistic dyno 183 hp and 167 ft-lbs!!! That kind of power at 2380 lbs is very hard to beat.

matt

IRA who, and what kind of car??

[Ron Earp]

I sure hope Ira's car in the new Grassroots was on a very optimistic dyno 183 hp and 167 ft-lbs!!! That kind of power at 2380 lbs is very hard to beat.

matt

Greg Ira, Guy Marvin, 240Z we race against down here in the SE. Painted in a Gulf scheme. Nice fellows, excellent drivers.

No joke. If that is rear wheel hp then that'd be around 210hp at the flywheel. Stout.

But on the other hand my old motor put out right at around 168 rwhp on the same Dynojet we've been using for years. I sure hope the new motor will dyno at least little higher and that puts it in the ballpark. Heck, with A cars making 155+ whp and some S cars reported to be at 180+ you've got to be making serious power to be a contender.

[jmark]

Greg Ira, Guy Marvin, 240Z we race against down here in the SE. Painted in a Gulf scheme. Nice fellows, excellent drivers.

No joke. If that is rear wheel hp then that'd be around 210hp at the flywheel. Stout.

But on the other hand my old motor put out right at around 168 rwhp on the same Dynojet we've been using for years. I sure hope the new motor will dyno at least little higher and that puts it in the ballpark. Heck, with A cars making 155+ whp and some S cars reported to be at 180+ you've got to be making serious power to be a contender.
Sam builds Greg's EP 240Z motors and Guy's ITS 240Z motors as well.

[xr4racer]

Ron, I agree the horsepower race is on but 183 in a 2380 lb car? I hope that is a misprint. The discrepancy between the torque and horsepower 183 vs 167 may be a clue that the HP is wrong. I thought the torque and horsepower were almost even on the early Datsuns.

matt

[TomL]

There's more than one thing that doesn't quite add up. As Matt notes, the relationship of TQ and HP is completely different than for Ron's engine - it implies a much higher HP peak RPM and/or a much flatter (and lower peak) torque curve. Second, what 2380 pound car are we talking about? Gee, that's the allowed weight for the EP car, not the ITS. And I'd be willing to bet that the engine numbers are, too. You did say Ira's car (i.e., the EP car), right?

Don't try to scare everyone! :eek:

[MIKEL]

Ira,s car makes a lot more than that(aprox 250HP at crank) and should weigh min of 2255 for the setup he has. Sam has put a lot of real tricks into that motor (EP allows anything in the block and lots of port work)Sam was still tweaking the IT motors(intakes exhaust configures) dont be suprised if he dose not get 200+ out of them one of these days. Like you said it aint cheap but you get what you pay for and Sam is one of the best.:eclipsee_steering:

[lateapex911]

my book shows the spec weight of the 240Z in ITS to be 2430.

[MIKEL]

You are talking about IT, Grg Ira,s car is in EP. Completely diff animal.

[JeffYoung]

Lotsa confusion in this thread.

Ira has both an EP and an ITS car. I have not yet seen this months GRM; was it the ITS car or the EP car on the dyno? Engine dyno or chassis?

183/167 sounds like the IT car on a chassis dyno to me. I've seen several IT dyno sheets for 240zs mid 170 at the wheels, my guess is that is where Ron's will be too. The curves and relationship are different on the 260 for a reason -- a bit more stroke.

ITS power in the SEDiv is pretty stout. I should have a dyno sheet here to post shortly as well...

[xr4racer]

Jake, you are right, 2430 is what it should be. Both of his cars are in the mag and both the EP and ITS are listed 50lbs light. The ITS car is the one I quoted at 183/167 what does the process use for the 240Z HP? I assume much less to be 2430.

matt