Gains from ECU Mods

[MMiskoe]

Now here is a question - Since (currently) IT is strictly normally aspirated engines, how much (what percentage) can actually be gained simply by re-curving the map? I know the Miata's picked up about 4% on PEAK power by leaning out the upper part of the curve on some of the later 1.8's (1996 to 1997?). But on a system that measures MAF and provides fuel accordingly, how much is there to gain in this? (this excludes some of the old systems like Bosch D that has a fixed map and works off manifold vacuume which doesn't easily pick up on improvements to the rest of the motor, I think they really can make some gains by scrapping the OEM system & starting over)

With all the questions getting raised about if the ECU rule should get changed, I am curious what sorts of advantages are really being had, and by how many cars.

- what overall gains are made by starting from scratch?
- how many cars in IT can take advantage of an aftermarket system? I doubt that there is enough interest in the Wombat GT for someone like MOTEC to bother with it. BMW 325's & 2nd gen RX7s yes.
- what overall gains can be made w/ the current rules, but simply re-chipping/flashing the OEM system? Therefore what is the difference between this and a start from scratch system?

Lets here it, I'm curious.


Matt

[Andy Bettencourt]

Matt,

I hope other people will tell you what they have seen. I have seen the following (they may not represent best of breed but just my own eyes, both Dynojet):

Rotory: Well known Programmable ECU - 5 more peak whp, 10 more peak wtq and a general flattening of the TQ curve.

I have also seen that same set-up make 1 more peak whp and only 2 more ft/lbs on a well-built and tuned unit.

I hope to figure out how to get a Progammable unit to work on the Miata this winter. Bottom line, I can't give away any power in this class in a Miata.

Steve L from BBRacing should post, he just did some tuning on a 240SX...

AB

[BMWE46ITS]

Originally posted by Andy Bettencourt@Nov 19 2005, 11:37 PM
Matt,

I hope to figure out how to get a Progammable unit to work on the Miata this winter. Bottom line, I can't give away any power in this class in a Miata.

AB

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Andy, why is it hard to find a progammable ECU for a Miata, should be really strait foward or am I missing something?

[Andy Bettencourt]

Originally posted by BMWE46ITS@Nov 22 2005, 01:56 PM
Andy, why is it hard to find a progammable ECU for a Miata, should be really strait foward or am I missing something?

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Making sure the options all fit in the stock housing.

[SPiFF]

~6hp with a Hondata system on my ITS GSR.

[jamsilvia]

Originally posted by SPiFF@Nov 20 2005, 08:14 PM
~6hp with a Hondata system on my ITS GSR.

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On my street version 240SX (same motor as the racecar - i.e. stock internals, but has cams installed) - there was a 13HP peak gain and 9 torque. The only change on the car (other than weather) was the ECU:

Before and after ECU dyno charts

The ECU was a commonly available one for the Nissan's - a Jim Wolfe Technology N/A program.

Another advantage with the ECU in this case was a raise of the rev limiter. The S14 240's had a 500 RPM lower rev limiter. The ECU pushes the limit to around 7000 RPM like the earlier cars, and as you can see with the original chart, it was a needed bump as the new cams were just making peak power at the old rev limit.

Hope that's useful info for you,
joe

[Gregg]

About 12 ft-lb tq, 10hp and a general flattening of the curves by re-programming the stock PM6 ECU of my CRX Si's D16a6 motor.

Edit: All work was done on the same Dynapak chassis dyno.

[Bill Miller]

Joe,

Good information, but not really a valid data point due to the cams.

[Joe Harlan]

Originally posted by Bill Miller@Nov 21 2005, 02:19 PM
Joe,

Good information, but not really a valid data point due to the cams.

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Why not valid if cams were there on both runs? I believe in looking at his data the percent of gains is about the same. The issue with te JWT program is it is still generic to what Clark (programmer at wolf) feels is correct. Without having somebody burning chips while at the dyno your not going to extract the best map for your car.

[Bill Miller]

Joe,

I said that because I saw that they were JWT cams and a JWT box. If nothing else, I would think the maps would be optimized for the cams, since they both come from the same vendor. Even if that's not the case, you can't say that the new box doesn't take advantage of the new cam profiles. Without knowing more about exactly what changed w/ the new cams (was it just lift? did duration and overlap change? are the lobe centers still the same?), you can't say the gains w/ the new box were just due to the new box.

I'll give you an example from the old Rabbit GTI days. You could put the bigger throttle body and the G-grind cam on, but if you didn't change the horrible 'toilet bowl' exhaust manifold, you would see little to no gains. But, if you used even a stock Rabbit dual-port manifold, you'd see the cam/t-body wake the car up. If you just looked at a dyno sheet w/ the cam/t-body, w/ the stock manifold, and then one w/ the dual-port manifold, you'd think that all the gains came from the manifold, and nothing from the cam/t-body.

[Knestis]

I can get up to 20 hp from this.

K

[jamsilvia]

Originally posted by Bill Miller+Nov 21 2005, 05:08 PM-->

I said that because I saw that they were JWT cams and a JWT box. If nothing else, I would think the maps would be optimized for the cams, since they both come from the same vendor.[/b]

The ECU that JWT offers is the same reguardless of the cam profiles. I actually ordered the ECU before the cams - but due to long waits on the JWT programming at the time, the cams came first. So when I ordered the ECU, I didn't even have planned to get the cams in there anytime soon!

Originally posted by Bill Miller@Nov 21 2005, 05:08 PM
Even if that's not the case, you can't say that the new box doesn't take advantage of the new cam profiles. Without knowing more about exactly what changed w/ the new cams (was it just lift? did duration and overlap change? are the lobe centers still the same?), you can't say the gains w/ the new box were just due to the new box.

You do bring up a valid point. The engine WILL breathe better with the cams. So the ECU, even in a state of tune NOT specific to the cams, could make more HP automagically.

The cams, BTW, run the same lobe centers, but have a longer duration (hence more overlap) and more lift. However, the motor in this car is not built. There's no port matching, no building of the top end clearances. So while the cams let the engine breathe better - so do the tricks that you are allowed to do to an IT motor.

<!--QuoteBegin-Bill Miller@Nov 21 2005, 05:08 PM
I&#39;ll give you an example from the old Rabbit GTI days. You could put the bigger throttle body and the G-grind cam on, but if you didn&#39;t change the horrible &#39;toilet bowl&#39; exhaust manifold, you would see little to no gains.

Note, that how much the engine can breathe is independant of the ECU. (edit: well at least in the case of non-VTEC/VANOS type motors, where the breating can be somewhat ECU controlled - but the 240 is not er....so technologically advanced!). In your example, however, you are pointing out gains due to increased flow on one side of the engine vs the other. These 2 variables, however, are NOT independent. Flow out affects flow in on the motor. And vice-versa. So it does make sense to see the results you stated.

As was pointed out, however, the dyno runs in my car were both with the same exact mechanicals. So although I agree with you that a cammed motor will most likely see more gains from an ECU than a stock motor, I don&#39;t think that it would be significantly different than a built motor (and actually, I&#39;d guess that a rebello built motor would see even better gains - even tho the ECU is not optimised to the build). I&#39;d also expect that a custom ECU program would see even more gains than the generic JWT item (that is programmed to be compatable with a large number of different states of tune).

joe

[Banzai240]

Originally posted by jamsilvia@Nov 22 2005, 02:29 PM
I actually ordered the ECU before the cams - but due to long waits on the JWT programming at the time, the cams came first. ...

So while the cams let the engine breathe better - so do the tricks that you are allowed to do to an IT motor.


joe

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Please... PLEASE Tell me that you are talking about a NOT-To-be-used-for-IT-Racing motor here... and that you are not referring to a CAMMED engine in your ITS S13...

[jamsilvia]

Originally posted by Banzai240@Nov 22 2005, 10:09 AM
Please... PLEASE Tell me that you are talking about a NOT-To-be-used-for-IT-Racing motor here... and that you are not referring to a CAMMED engine in your ITS S13...

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BWHAHAHAHAHAH!!!!!!

Yes! - that dyno&#39;d motor is in my "track car" S14. It&#39;s too pretty to have the fenders knocked in with IT racing!

My S13 motor looks like this:

My s13 motor

It has...er...had 175k on it, and was never opened before it was "prepared" to the state you see it in the pics.

joe

[Bill Miller]

Joe,

I used the Rabbit GTI case as an example of how parts worked together. And while the JWT box may be the &#39;standard tune&#39;, I would think that they set it up to work w/ their cams. Gotta work off of same baseline when they&#39;re programming it.

[Joe Harlan]

Originally posted by Bill Miller@Nov 22 2005, 08:24 AM
Joe,

I used the Rabbit GTI case as an example of how parts worked together. And while the JWT box may be the &#39;standard tune&#39;, I would think that they set it up to work w/ their cams. Gotta work off of same baseline when they&#39;re programming it.

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Not the case....

[Bill Miller]

Originally posted by Joe Harlan@Nov 22 2005, 11:36 AM
Not the case....

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So please elaborate Joe. They code the ECU up to work better w/ stock cams? someone else&#39;s cams? an imaginary cam?

[Joe Harlan]

Originally posted by Bill Miller@Nov 22 2005, 12:47 PM
So please elaborate Joe. They code the ECU up to work better w/ stock cams? someone else&#39;s cams? an imaginary cam?

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Performance is not just a single horsepower number at wide open throttle. Throttle response, drivability and efficiency (maximum power to fuel ratio) are also among the true qualities that define performance. The original ECU program is limited by compromises made in these areas by the factory in the elusive attempt to satisfy "all the people all the time". POP or Performance Optimized Programming is the technology we use to unlock these compromises. POP is much more than just changing a few numbers in the memory maps of the control program. Without a thorough knowledge of the engine management control system and a skillful ability to optimize all areas of the programs inside, this extra performance is untouchable. Optimizing begins by addressing the fuel and ignition timing demands required for crisp response during throttle position changes. It requires that the actual memory maps be extended far enough to reach the high rpm and load limits of the higher capability of the engine. This can be critical to safe operation at higher output, since the stock maps are not designed with memory cells that address the higher loads and rpm (the stock program can only make a best guess at the needed fuel and ignition timing). Variable computer controlled cam timing is an innovation used on many Nissans, optimizing these cam timing points for load and rpm is a must for optimized performance. Once all of the detailed "housekeeping" work is finished, such as raising the rpm limiters and removing the speed limiters, the "maps" can be tuned to perfection. Many days of dynamometer and road testing are required to achieve the maximum safe performance level from the vehicle. Air/fuel ratios and ignition timing are constantly monitored throughout every load/rpm combination and new values are continually downloaded to the engine control unit and evaluated for optimum results. All of this information is then assembled into a final program which is installed and tested in every unit before you receive your upgrade package, making it a "plug and play" upgrade! Performance optimized programming is truly today&#39;s tuning tool for performance, offering a unique ability to "surgically tune" the engine without disturbing the light throttle and cruising modes of the original program. Tuning is done outside of these areas to maintain the original fuel economy, and smooth drivability, while maximizing performance where it really counts.

Here you go Bill try a little research next time. It ain&#39;t that hard to get. This is what you get when you order the wolf box for a stock car. They will do custom programming for a fee.

[Geo]

Originally posted by Bill Miller@Nov 22 2005, 12:47 PM
So please elaborate Joe. They code the ECU up to work better w/ stock cams? someone else&#39;s cams? an imaginary cam?

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I&#39;m elaborate a bit Bill. I&#39;m quite familiar with Wolf and have been there a few times and one of my really good friends works closely with them on a lot of stuff.

JWT&#39;s basic ECU remap is for a car with stock components and their POP Charger (cone filter with a huge machined adapter with a big venturi). Beyond that, they have remaps for a wide variety of things. It&#39;s pretty amazing the number of maps they have available, all optimized for the various components or very very similar set-ups.

So, yes it&#39;s possible to get a remapped ECU for an otherwise stock engine. They are pretty unique in the aftermarket ECU tuning world in breadth of their offerings (and not junk offerings either).

[MMiskoe]

ECU tuning is a definte gain and one that is worth enough for people to after and have it be a competative gain. Didn&#39;t really need to ask that.

Now I should have posted my question differently.

What gains can be had w/ a completely built from scratch system (IE Motec) that are not availble by reprogramming/chipping the stock ECU?

What I am curious about is what is available through a completely custom designed system that is not available by re-working the existing system? IE for the guys that do go out and get the custom made system worth 10 years of entry fees, what do they gain that they couldn&#39;t get by simply reprogramming what they already had?