MBC vs Chip

[Andy_R]

I've picked up quite a bit from reading through various related threads, but could someone who knows, sum up the advantage of a chip over a MBC.

And... assuming for now that a chip is the better solution, is there much variation from one chip to another?

[Doug]

see here: http://www.astb91.dsl.pipex.com/MountainChipMenu.html

[skywalker]

Hello,
I don't know if you've read the "massive overboost" post below yours - but thats me.... This is an area which I've had a few problems with myself!!
At the moment in time - I'm running a MBC, induction and stainless exhaust and have turned the fuel adjuster up to allow for the event of a "lean" mixture - not great for miles to the gallon - but good for the engine!
I have two different types of chip- 1Xsuperchip, and one that has been specifically made to use along side a MBC which basically just remaps all of the downfalls of just using an MBC. (I.e- allows the ecu to sense various changes etc and react to them as it see's fit).
The superchip is similar to the one shown on the link you were given allowing the car to boost to 0.9bar - However - my "superchip" chip is actually for a S2, not an SE which means that after about 10 mins the engine management light comes on because the ECU thinks there's a problem with the CAT..... there is - is hasn't got one!!
Personally - for the difference in price between a Chip and a MBC, I'd opt for the MBC unless your intending to track it- personally from the experience's I've had from my 3 elans, providing the mixtures increased and Its getting a better air flow (I.e good filter or induction) its benifits are much the same. It also allows you to turn it down and up as you wish without striping out the ECU to replace the chip. Therefore, if you want to drive it in the wet - at least you can turn it down a touch - try controling 0.9bar of boost in the wet without any LSD taking off at a roundabout!! Interesting!!
Hope these thoughts help you - other may disagree - but thats the beauty of an open forum disscusion!
Dave

[Monty]

have two different types of chip- 1Xsuperchip, and one that has been specifically made to use along side a MBC which basically just remaps all of the downfalls of just using an MBC. (I.e- allows the ecu to sense various changes etc and react to them as it see's fit).

I could be wrong,
With an MBC the ECU will not know what it`s boosting at, so cannot adjust fuel for that boost.

However - my "superchip" chip is actually for a S2, not an SE which means that after about 10 mins the engine management light comes on because the ECU thinks there's a problem with the CAT..... there is - is hasn't got one!!

Don`t think thats to do with the cat but more than likely the missing O2 sensor

personally from the experience's I've had from my 3 elans, providing the mixtures increased and Its getting a better air flow (I.e good filter or induction) its benifits are much the same

As far as i`m aware u can`t adjust the mixture only through the ECU that`s why they invented the chip, in a stock M100 with and MBC & FCD when boosting above stock boost the fuel starts to lean out as the ECU still think it`s boosting at 0.65 bar and will not delivering the correct mixture for say 1 bar.

Personally - for the difference in price between a Chip and a MBC, I'd opt for the MBC

so i can`t agree on that one, with an MBC u`ll only beable to get to the fuel cut (0.9 bar?) after that u`ll need to fit a FCD. So for roughly £100 for a ESM Everest chip i don`t think the chip can be beaten

[skywalker]

Just furthering on from Monty's comments- The ECU dosn't need to adjust the mixture - you can manually increase the amount of fuel by using the mixture screw at the top of the throttle body - takes the need away from the ECU - And the actual fuel cut off on an elan is 0.9 bar or there abouts (Of the three I've had- only one has had a FCD, none chipped and all have had a MBC, all have boosted to the 0.9 mark, and only beyond that has the engine management cut the fuel), not 0.65 bar - an FCD is only really needed if your intending to hit the 1 bar marker and beyond.
The everest Chip is good value at the £100 mark, but as stated before - you lack control in variable conditions - at least with the MBC you can turn it down/off. Also depends if you're intending to thrash the pants off it everywhere you go. A in car MBC is probably the best solution!!!!
My point though - everyones has their own opinions!!!

[ESM]

Skywalker the screw on the top of the throttle body is meant to adjust the passive idle speed into the range where good ECU control of idle can be achieved by the ECU - to suggest this significantly alters the mixture across the rev range is wrong - especially in catalyst equipped cars where the mixture is actively controlled by the ECU. Monty is correct when he says fueling can only be altered by changing the chip (unless you fiddle a sensor input, mess with the fuel pressure - non cat only- or add a piggyback fuel controller)

Regarding variable conditions and boost control with the chip the boost target set is related to throtle position - its roughly proportional from 25% throttle where the boost target is zero to 100% where the target is 0.9 (Everest) or 0.8 (Kili). Since passive wastegate opening occurs at 0.5bar or so you don't see extra boost over stock until you go past about 75% throttle. If you don't give it a lot of throttle angle you don't get a lot of boost - its much better than an MBC you don't have to get out and fiddle with it you simply get the power progressively with throttle opening.

You're right that everyone is entitled to an opinion but the ones you have put forward aren't based on accurate information.

[Monty]

Dave u`r wrong on the boost, u need to read the manual, i haven`t a clue on the mixture screw at the top of the throttle body but is that not for the mixture for idleing

[Sy V]

"in car MBC is probably the best solution"

This was true, two/three-years ago.

[Candles]

I'm sorry to just camp with the big Sy, ESM & Monty crowd, but I have to disagree with you Skywalker:

Car manufacturers have spent a lot of money installing a clever variable power valve to cars for ages now so that having a powerful car in the wet doesn't make it like a wet Labrador puppy on a laminate floor. They call it the 'throttle' or 'accelerator.'

The boost cut is at 0.92 Bar on a stock ECU. If your MBC has been turned up enough to ever see a decent amount of boost at other times, you will have seen overboost cut when revving high at WOT for long periods. If only 1 out of 3 of your Elans has had an FCD, then the MBCs haven't been giving you maximum performance. The chip combines the best of both worlds; high boost targets low down without the runaway seen with a bleed valve, AND the safety of still having the fuel-cut if the boost runs away (FCDs remove this safety feature).

Well that's my 1p spent. As you say, this is a forum where open discussion is encouraged. I'd like to see an accurate list of the advantages of an MBC over an ESM Mountain Chip. I'll start with the first two:

1) Cost is lower, if you use the Rob-C DIY method.

2) You don't have to break the seal on your ECU.

Candles.

[skywalker]

Steady on Ladies!! Handbags!!!!!
Sorry for posting MY personal experiences with chips/MBC's - as I say - these are MY experiences, and obviously not shared with others.
I must say, it seems funny that the chap who started this thread posted this tuesday - and only Doug has given him the time of day to give him his opinion...... where, as soon as something is said to differ from one persons view...... there's several others joining in!!
I was sharing my opinion of the OVERPRICED "superchip" chip retailing at around £500 - not ESM's everest, priced at the very respectable £100.
I must say, I will - if he'll sell me one now!! - try one so I can see the benefits myself.
Sorry for sharing my views - not based on facts - but my own experiences - but from the two Chips I have had the chance to use and test - there's no point in either of them - frankly, no real benefit to drive over a MBC - as for ESM's..... I have no idea - as i'm yet to have had the pleasure of trying it!!
Just thought I'd better show that I don't take offence to anyones comments!!!
Until next time guys!!

[Andy_R]

I appreciate you chipping in Dave (no pun intended) - not least because I've learned a thing or two from the others giving you a bit of a slating!!

I started the thread because, after having spent 18 ish months since buying my Elan rounding off the inherited rough edges, I've begun to think towards a little more boost. I've always thought an MBC was a bit too crude, but was put off chips by the prohibitive price, untill Doug pointed me in the direction of Everest. Since Tuesday, I've been sold.

On the subject of mixture, my car is running lean (MoT emissions result of less than 0.5%). Would an Everest chip take care of this, or do I need to sort that out separately?

And...how difficult is it to fit a chip?

[ESM]

Have you tried ajusting the CO potentiometer? (slightly above and to the right of the ECU - assuming you have an SE with no air-con).

[Andy_R]

I haven't. Need a bit more detail though... how + what does it do?

[ESM]

This is from the engine management manual:

[Doug]

I've always thought an MBC was a bit too crude, but was put off chips by the prohibitive price, untill Doug pointed me in the direction of Everest. Since Tuesday, I've been sold.

did I point out the money-back guarantee on the chip

Alan is THE MAN

[Doc Fizzix]

Ok, here is a little fuel for the fire

I have a CA version car and got the top chip and my car actually lost boost and ran like crap BUT the strange thing is that when I ran the car with the MBC and the chip, my car ran like a rocket!

I have no idea why and maybe when I get my motor out and the new one in I can find the problem, but for now I like the MBC and the chip together

I do have to say that Alan and Doug were great! They sent me two other chip for free trying to help me find the problem, they are great guys and know their stuff. I still wish I knew why the chips does not work in my ride but for now I am still-a-smiling

[Monty]

Dave,

A bit of a discusion never hurts anyone and bennifits the forum. Just wondering maybe the 3 M100 u`ve own had a larger bore aftermarket exhaust and thats why u was hitting 0.9 bar

[Nige]

Prior to ESMs chips MBC+FCD was the accepted way to go, either expensively with a BBR kit or cheaply with a home brewed version courtesy of Rob C, Rob B and others. I went that route, initially with just an MBC which had to be adjusted to ensure I didn't hit fuel cut at .92 bar. I then built an FCD and could run 1 bar or as much as the turbo could deliver if I wanted. I now run an everest chip and get controllable boost related to throttle position, if I want all the power there is I simply nail it, under UK road driving conditions that is a rarity.

The workings of the BBR conversion are well known, the workings of the superchip are, I believe, still something of a mystery around here and I certainly wouldn't pay £500 for a box that says 'and now something magic happens'. Interesting point on exhausts. John W did some back to back comparisons of standard, chipped, MBC'd standard exhaust, big exhaust permutations. An otherwise stock Elan with a 2.25 " exhaust can get to around 200BHP through boost creep alone but the delivery of both power and torque is not really under the full control of the driver and I doubt it would be useable under most driving conditions as the Dyno is an artificial set of circumstances anyway.

[ESM]

I have looked at the code from a 1499 based 'upgraded' PROM supplied by a a well known chipping company and run a compare with the stock 1499. Two bytes were changed. On analysis of the disassembly I found that one of the changed bytes breaks the call to the error subroutine made when the overboost criteria are met (and I mean breaks - the call is broken so a bunch of arbitary code gets executed instead) and the other change is to an unused byte and its purpose is simply to balance the change made to the first so that the checksum comes out unchanged and the PROM passes the power on self test.

In practice this meant that something, to the driver, much like the normal overboost fuel cut occurred on overboost but the CEL did not light nor did the code set. The cause of the abrupt power loss was in fact the 'crash' caused by the arbitray code execution I mentioned above rather than any deliberate engine protection measure.

If you look at the highway.boost.creep.ecu log at 245.8s you can see all the parameters that are put through a moving average smoothing filter get reset to zero (speed for one) and some unsmoothed variables are set to zero as well, a/f ratio & knock count included, when the corrupted overboost call is executed and this is what causes the ECU's confusion and the fuel cut.

I hope they had later versions better than this because its pathetic that this was given to someone to put in a car.

This is my opinion based on my interpretation of a code disassembly. I may have got it wrong, although the evidence in the log I mention above supports my interpretation.

[Doc Fizzix]

Is there a quick translation on this? Does this address my problem on my car?