free hit
counters
new ECM options? - ECU/OBDII - The Lotus Forums #ForTheOwners Jump to content


new ECM options?


hyteck9

Recommended Posts

Hello all,

 

I have been reviewing this section of the forum, and it appears the most popular ECM remap options mentioned are the PUK #RED chips. 

 

But. . .  those posts are several years old at least.  :-/

 

Are there laptop options yet to rewrite the maps myself?

 

Any serious technical reason folks haven't gone to stand alone engine management?

 

Thanks!

 

:-)

 

 

Link to comment
Share on other sites


Upgrade today to remove Google ads and support TLF.
  • Replies 21
  • Created
  • Last Reply

Top Posters In This Topic

Hi Brian

 

I considered replacing the stock ECU a few years ago .

 

The area needing the most thought is the interface with the ABS controller , the standard fit Cobra alarm would need a bit of re thinking as well

 

Generally , the Esprit V8 ECU is not a bad unit , it is after all a modified Corvette GM one

 

I think Red race chips combined with high flow cats and K&N or Green air filters is still the best way to go

 

Regards

 

Dave

Link to comment
Share on other sites

Only the base electronics are GM , the software is all Lotus designed specifically for the Esprit V8 . When you consider the two cars the corvette was normally aspirated where as the Esprit is turbocharged

I think Johan and a few others have interrogated the mapping and would be better placed to answer your question

All boost calibration is held in two eeproms ic19 and ic20 in the ECU , if you socket these two devices you will have a range of plug in options to go for

 

Regards 

Link to comment
Share on other sites

Thanks for the info. 

 

Are the Red Chips still available by the way?

 

My most major concern is that the Red Chips were developed years ago and do not take in to account the efficiency maps of modern turbos which have increased as much as 40%. 

 

If I had total software control it would be most advantageous.

Link to comment
Share on other sites

The ecm is made my EFI in Italy.. I don't believe it shares anything with GM.. But.. I've been wrong before. EFI has made Stand-alones for years. Many people have tried to communicate with EFI in Italy and have had no luck in getting any software information. The system is programmed in an MS-DOS based system and only a few people know how to re-program them. This is why I went stand-alone -- the factory system is not easy to reprogram.

Modifying esprit's.. now that's fun..

PS... I AM NOT A CERTIFIED MECHANIC.. I Have chosen to help those in need, in the past and must not be construed as being a certified technician.

Link to comment
Share on other sites

id think cost effective wise the chip is the way to go. If you're going mod crazy and dont need to pass obd2 emissions than there's plenty of standalones that can do the job. Motec (probably top dog and pricey - tons of tuners and used in professional racing) , syvecs (not so big in the u.s. but europe very popular), aem (lots of tuners, one of the cheaper choices), proefi (limited on tuners), then there's a ton of cheaper or  less knowns.... hydra, vipec, megasquirt (im sure i missed alot). What kind of crank and cam triggers do the esprits use 16 or 24 tooth? If it's not too unique maybe even a gm ecu from a vette/lsx will work. There's plenty of really good tuning programs and extra capabilities for those. The standalone is always the best choice but much less cost effective. When i put aem v2 on the supra it allowed me to add electric fans, update my knock sensors to newer style, change dead times to calibrate the injectors better, electronic boost control, boost by gear, fuel pressure, ethanol content sensor, add a m&w cdi igntion box etc....

Link to comment
Share on other sites

I'm not looking to go crazy, like ethanol, etc..   But the turbos I'm considering are a giant leap forward, and the new transmission I'm putting in will let me use every bit of it.  Other than AIT's which I will solve using some kind of cooler (undertermined)...  the ECM will be the limiting factor.

Link to comment
Share on other sites

maybe something like the map ecu will work good for that application. http://www.mapecu.co.nz/ It's a piggy back with alot of cool features, pretty decent pricing. Will allow for timing and fuel map changes to help with the bigger turbos. You'd obviously need someone who knows what they are doing to let it mesh well with the stock ecu. meth injection is probably your best bet for cooling if you are trying to cut costs and not add intercoolers.

Link to comment
Share on other sites

Once you are into hybrid turbos, intercoolers, bigger injectors etc then the standard ECU with Red Race chipset will be enough. Beyond that you are into forged pistons better rods and a whole list of upgrades to keep it reliable.

 

Have a look at Mike Sekinger's blog.

Link to comment
Share on other sites

Thank you for the replies.  Let me walk through my logic one more time , partially for my own sanity. 

 

I'm not looking to rebuild everything in the engine... after all this car is basically mint and has just 12k miles on it.   I'm trying to react responsibly to the overwhelming claims that the turbos fail prematurely and the transmission is weak.

 

I got the new trans (have not installed it yet), and want to replace the well aged 15 yr old turbos before they grenade and do more down stream damage.  The problem is even the smallest turbo on the market today wants/needs to breathe better than the 8psi our car limits them too.  Running in constant overboost condition will potentially cause more problems than I aim to initially fix so a code change is needed.

 

I agree Red Race chips should do the job (assuming they are still available).  I would want to know the a/f they run.  I admit I am a control freak and would prefer laptop modability <-- (I know this is not a real word)   I'm not too fond of piggy back units as they run off of too many assumptions.  I would have no problem going to a stand alone unit though someone mentioned ABS integration being an issue, which is concerning as its a proper feature to have. 

 

I haven't forgotten to address the increased intake temps either, I just have not decided how to do it.  Being such a low mile vehicle I really don't want to start cutting it up to install Water/air coolers.  Again if the Red Race chips are running 12.5 a/f vs. 14.7 than that will help with cooling too.

Edited by hyteck9
Link to comment
Share on other sites

^correct.. the afr with red race is RIDICULOUSLY rich. And.. the timing is really retarded.. like 6-8 degrees of advance at full boost. Now.. you can go with any stand-alone you want. Leave the factory ecm take care of extra bits.. and just take all the signals that the factory ecm uses to do fuel and ignition away from it. Also.. disconnect the check engine light wire, as it will become annoying.

The advantage of using the Vipec V-88.. is I have a base map for it. However, my base map is using intercoolers.

Now.. as for bigger turbos.. that's why the engine was rebuilt in mine. The car ran 500+hp on the dyno before it promptly blew up. This was on the red race chip.

Modifying esprit's.. now that's fun..

PS... I AM NOT A CERTIFIED MECHANIC.. I Have chosen to help those in need, in the past and must not be construed as being a certified technician.

Link to comment
Share on other sites

The ECU was made by EFI in Italy as stated above.  All variants of the ECU provided by Lotus only support .75 BAR of boost and provide ever increasing rich mixtures when any method is used to push boost beyond .75 BAR. As rich as 10.5:1 when MAP values reach 1.0 BAR. Various 3rd party chipsets claim higher boost levels with more correct AFR's, but when I've asked for documentation from dyno runs, nothing was provided. EFI did provide a DOS based software tuning tool, which I have, for their old race ECU, which the Lotus ECU was based on, but I have never been able to get the "template" for the Lotus ECU. Lotus has carefully sealed up the access. The boost and timing tables in the Lotus' ECU's has been carefully mapped to limit torque, to protect the rather narrow rod bearings and aftermarket chipsets probably don't comply with this requirement.  The torque curve of the 918 engine, without any boost, is rather strange due to the very, very restricted packaging of the log type exhaust manifolds. The fuel mapping also must compensate for this. Lotus's reputation as a premier engine tuner and designer is well founded. Even with a aftermarket ECU, like Motec, it's still a challenging project.

The Older I get the Faster I was

Link to comment
Share on other sites

Great comments from all above.  It makes me want to dig in more and more. 

This is the first I have heard that the rod bearings are something to be cautious about.  This comes as a surprise to me.  At the OEM rated 295 ft./lb of torque,  that is only 37 ft lb. (approx) per cylinder.   60lb.ft./cyl  has been easily accomplished on most economy cars' stock internals. So doing it on a Lotus race-heritage based engine should be a walk in the park for it I would think. One would need to manage cylinder pressure of course and pulling timing isn't always the best solution.   Pulling timing means you have to add more boost to get the same amount of work... and that means more heat and higher cylinder pressures.  How do you want your next extra +30 ft.lb/tq served up?...  with more heat or with a more efficient turn of the crank?  Oh, you like efficiency!  great.  Run more aggressive timing.  I know they were looking to save the transmission and backed all the timing out of this car, but it just "feels" wrong in my racing soul to not let this car do what it is really capable of.  If Lotus won't build a new Esprit, than I am going to enjoy this one to its fullest.

Link to comment
Share on other sites

Hyteck9, your math is incorrect, the cylinders fire sequentially not in parallel, so you can't divide the rated torque by 8. There is some parallelism in that each cylinder also does not contribute the entire torque rating. The rod bearings are designed to withstand the torque rating of the stock engine as is the entire drive line, but not much more in keeping with Colin Chapman's philosophy. 

The Older I get the Faster I was

Link to comment
Share on other sites

Thanks for the reply WEllison,

 

Of course you are correct.  Not all 8 cylinders fire at once.  I didn't mean to imply otherwise.  I do think torque in its most basic definition takes in to account a full 360' turn of the crank though, which, would permit all cylinders to be considered.   In any case, speaking in terms of  power per cylinder is meant only as a rough gauge to express durability (or lack there of). 

 

You raise another interesting point though.  Since this is a flat-plane crank engine , I would be curious to know if that configuration benefits both rod and crank bearings alike to have a somewhat reduced amount of lateral stress from the shared firing order.  I'm always more curiosity than answers though so feel free to keep steering me in the right direction.  :ice:

Edited by hyteck9
Link to comment
Share on other sites

I had my Carillo's made up with a slightly wider base for the bearings. There is a part of the crank that is rough at the edge and designed (presumably) for oil dispersion. However, The extra width of my rods enabled me to go about .020" wider on the rod bearings.. It's not a lot, but when coupled with the "race bearing" technology from ACL.. it should enable me to put quite a bit more power down.

Modifying esprit's.. now that's fun..

PS... I AM NOT A CERTIFIED MECHANIC.. I Have chosen to help those in need, in the past and must not be construed as being a certified technician.

Link to comment
Share on other sites

The flat plane crankshaft benefits from reduced weight counterweights, as the "paired" cylinders fire at 90* as the cylinders are separated by 90*, but there are large harmonics which occur and can only be tolerated in smaller displacement engines. Flat planes sound weird, but rev fast. Each cylinder serially provides the torque, there is an additive effect only due to torque overlap, I have no idea what the torque decay of each cylinder is, but I bet Lotus does.

The Older I get the Faster I was

Link to comment
Share on other sites

WEllison,   I was looking threw your datalogs from another thread.  You have done a tremendous amount of work and the results are every bit of fantastic.  Are you running a Motec stand alone?  Did the coolers and piping ever become a sale-able package?

If I didn't live 3,000 miles away , I'd buy you a beer or two.  :unworthy:

Edited by hyteck9
Link to comment
Share on other sites

Mark, Did ACL make your bearings out of Chev. bearings?  Mike S. had some made up by ACL several years ago and I would like to know if they are still available.

Hi Wayne.. they are not Chev Bearings. And.. ACL did not make them up. I am working on a solution for us for the future. Mike did have a few sets made up, by a guy in the UK, but the supply has run out. They are tabless bearings by the time you're finished making them. I had to finish mine with a hand file after machining them. Tabless bearings can make one nervous, but the bearings are not held in place by the tabs, they are held in by crush (Yes Wayne, I know you know this, but I'm sure most don't)

Modifying esprit's.. now that's fun..

PS... I AM NOT A CERTIFIED MECHANIC.. I Have chosen to help those in need, in the past and must not be construed as being a certified technician.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



Upgrade today to remove Google ads and support TLF.


×
×
  • Create New...