51 replies to this topic

[Billys Bits]

998 with stage one got to 90 going down a steep hill with a massive run up (private road)

[joel93]

95 1275 spi with k & n and rc40 decat about 50bhp
topped at 95ish

[lawnmowercrap]

Oh, and those resistor 'chips' do actually work.
They are literally just a resistor though, no chip. You put in place of either the MAF sensor or the coolant temp sensor.
It tricks the engine to thinking its either drawing in more air than it is, so it over fuels it, or tricks it to thinking its constantly cold, so it overfuels the engine.

The MAF one will cause the EML to come on though, because the 02 sensors wont agree with the overfuelling.

but that carn't add 20 brake

No point just get it re mapped or properly chiped.


That will just end up making the ECU go into limp mode, ruin in the lamda sensor and confuse the ECU which will just weeken the fueling off to bring the lamda reading back. Mignt even open the air bipass valve/idle control valve. And then bring up a fault code for the map sensor or mass airflow meter. Something along these lines

The fueling will richen up on accleration to the maximum needed to get the most out of a standerd modern engine. If you add air filter and add an exhuast maby port it and so on then it should be re maped for these modifactions to work. You can't trick an ECU all you'll do is confuse it.

Couldnt agree more on doing it properly, however, like I have previously stated the engine has to have the ability to over ride the ECU's decision to run open loop in order for the EML to be thrown on. And to find this on anything other than VAG cars is raaaaaaare.
Open loop is used during cold start where the ECU completely disregards the reading from the 02 Sensors because it is over fueling due to cold start. It stays in this mode until the Cat gets up to operating temperature meaning the 02 sensors are reading accordingly.

I see your point but it still wouldent work.

There is less power when the car is being overfueled to allow the car to start. Even on open loop the resister would still resist the already very low voltage signal from the maf sensor or air temp sensor making the signal even lower. The signal would be so week the ECU might not even reconise it as being there.

The correct air fuel ratio is stoichiometric or 14.7-1 messured in wieght, so on start up this isnt there and the ratio is not correct its rich as the lamda sensor is not reading as its not reached around 300degrees. The fuel mixture is rich... this dosent make more power.

This is open loop as you stated but in closed loop it also wouldnt work as the ECU will see the mixture is incorect and try to compensatete in other areas.
When you put your foot down the ECU ignores the Lamba sensor any way going into open loop and richens the mixture just enougth to get the most out of the engine depending on mass air flow and or throttel position.

You unplug the component that the resistor is plugged into therefor the only resistor in the circuit is the one you have fitted FORCING the ECU into permanent open loop, at which point ALL emissions based engine sensors are ignored, apart from Crank, Cam and Coolant Temp, which is never going to change because its resistored HENCE a system to be able to BYPASS open loop is required. It wouldnt physically be able to switch to closed loop without this system.
Stoichiometric value is old hat now, look into Straified and Homogenous injection anxd you'll realise that Stoichiometric value was pretty much abolished when MPi was introduced.

And when in closed loop the ECU NEVER EVER ignores the 02 sensors, to do so would make them completely pointless. It constantly monitiors them, and these are what allow the ECU to do in terms of injection and ideal combustion qualities. Petrol engines are controlled by air flow, hence the throttle butterfly (diesels being controlled by fuel flow, hence high pressure injection and NO throttlebutterfly), so therefor it is the MAF/MAP or Throttle Position Sensor that control the increase in acceleration, not the 02 sensors, these are post combustion so can only tweek accordingly. Upstream sensors should always read 0-800Mv under any load and downstream should be around 400Mv under any load. Anything other than that you have a massive problem. Or you have broadband 02 sensors fitted, but that takes us back to Stratified / Homogenous injection and to be honest, I cant be bothered to type the whole of my emissions based Higher National Diploma syllabus on here to argue over a resistor.

Edited by lawnmowercrap, 03 March 2011 - 10:40 PM.

[JustSteve]

My Horse Power = 0
My Top End = 0
My 0 - 60 = 2 years and counting...

My horse power = 0
My top end = 0
My 0 -60 = 6 years and counting .... pretty bad, saying that the cars 1999. It's spent half it's life off the road!

Oh, and my names also steve

[danrock101]

My 850 has about 25bhp or something daft, manages about 50, 60 with a tail wind.
The late 1275 engine had 58 at the wheels with a 3.1 diff and 13" wheels and that managed over 100 on the sat nav, probably a tail wind.

[aston19uk]

mine goes at the speed of light!

[Southy]

100bhp and 90 lbs ft tops out at 112mph on the road but managed 121 mph on the rollers.

[1984mini25]

mine goes at the speed of light!

But do your headlamps still work at that speed?

[lawnmowercrap]

mine goes at the speed of light!

But do your headlamps still work at that speed?

Good question!

[almarsh132]

I've got a completely standard 1275 carb, which has only just crept over 30k. So i would guestimate at about 40ponies left. Touched 100 on the speedo but also needed a change of underwear after! Once and never again!!!!
(private road)

Edited by almarsh132, 03 March 2011 - 11:06 PM.

[mk1leg]

Well since you've asked swiftune 1380 93bhp 100 torques according to slark race engineers RR and 110 on the M5 last sept whilst visiting the UK.......

[Andywade]

http://cgi.ebay.co.u...6#ht_500wt_1156

Thats what you need adds 20bhp!

do you think someone would be dum enough to buy one of them ahaha

Some people must, otherwise they wouldnt sell them.

I'm of the view that stripes make the bhp go up at least 15%

[Scallywag630]

HP....about 1000 (hampster power)
Torgues.....Wife does enough of that
Speed......nothing worth buying since the 70's

[Burnard]

Top speed 87.
Stage one 998. about 40-50bhp?

[new_zealand _minis]

140 bhp and 125mph easy . supercharged 1293