Dastek Unichip...
Discussion
A search reveals minimal talk about these piggyback chips which surprised me. A friend's E30 M3 has one, mapped by Circuit motors (next to castle combe).
I can't disagree with the output (250hp from a 2.3 215hp motor though it does have cams, carbon airbox, exhaust, different pistons) for which you can see a dyno chart here http://www.vr6oc.com/e107_files/public/1225642170_... . I drove the car and it was linear and progressive. Tiny bit stumbly from cold though. However it stank like a racing car when you followed and it was floored, and the owner said fuel consumption was horrific.
Can I put one on my Merc? It has jetronic. I would say ignition would/should not be mapped because it uses a different computer to the injection - do I lose out on that? But the injection has a method of varying fuel control pressure by supplying a current to an electronic actuator so can unichip deal with this? The car does have an air flow sensor... mostly. My fuel consumption is quite good at 28mpg always and I'd rather not lose it. Do they map part throttle as well as full?
I can't disagree with the output (250hp from a 2.3 215hp motor though it does have cams, carbon airbox, exhaust, different pistons) for which you can see a dyno chart here http://www.vr6oc.com/e107_files/public/1225642170_... . I drove the car and it was linear and progressive. Tiny bit stumbly from cold though. However it stank like a racing car when you followed and it was floored, and the owner said fuel consumption was horrific.
Can I put one on my Merc? It has jetronic. I would say ignition would/should not be mapped because it uses a different computer to the injection - do I lose out on that? But the injection has a method of varying fuel control pressure by supplying a current to an electronic actuator so can unichip deal with this? The car does have an air flow sensor... mostly. My fuel consumption is quite good at 28mpg always and I'd rather not lose it. Do they map part throttle as well as full?
Vixpy you didn't even need to post for me to already know what you thought! 
.
Tell me what's wrong with a piggyback on an old basic ECU if mapped well? Compared to the cost, effort and returns of going to aftermarket EFI (which would cost more than my car) it seems sensible from this inexperienced-but-willing mind. The factory map is close to correct, so Unichip can just slightly tweak as necessary (perhaps to take account for modifications) - can't it be trusted to do this basic task?
The guy did spend 3 days mapping this M3 - does that mean it was a b
h to get right or that it's been well done!?
Any comments on that curve there?
.Tell me what's wrong with a piggyback on an old basic ECU if mapped well? Compared to the cost, effort and returns of going to aftermarket EFI (which would cost more than my car) it seems sensible from this inexperienced-but-willing mind. The factory map is close to correct, so Unichip can just slightly tweak as necessary (perhaps to take account for modifications) - can't it be trusted to do this basic task?
The guy did spend 3 days mapping this M3 - does that mean it was a b
h to get right or that it's been well done!?Any comments on that curve there?
They can be a complete arse to get completely right. I've seen some shocking examples fitted to various cars. (including a 996 Turbo 
) However, i recently did an M3 evo with one fitted by someone who had spent alot of time on it and it was quite nice. I'm not a great believer in piggy back's. But if your only using it to control the fueling then it might work out ok. However i have no idea if it will work with the jettronic.
M3 curves look good
) However, i recently did an M3 evo with one fitted by someone who had spent alot of time on it and it was quite nice. I'm not a great believer in piggy back's. But if your only using it to control the fueling then it might work out ok. However i have no idea if it will work with the jettronic.M3 curves look good
Pentoman said:
Tiny bit stumbly from cold though. However it stank like a racing car when you followed and it was floored, and the owner said fuel consumption was horrific.
My 325 runs a Unichip mapped by Circuit Motors too, with exactly the same symptoms. Nice power and drive but drinks fuel and smells like a B plate fiesta.agent006 said:
Pentoman said:
Tiny bit stumbly from cold though. However it stank like a racing car when you followed and it was floored, and the owner said fuel consumption was horrific.
My 325 runs a Unichip mapped by Circuit Motors too, with exactly the same symptoms. Nice power and drive but drinks fuel and smells like a B plate fiesta.Did it give a power and torque gain? Do you have figures or a graph?
Pentoman said:
agent006 said:
Pentoman said:
Tiny bit stumbly from cold though. However it stank like a racing car when you followed and it was floored, and the owner said fuel consumption was horrific.
My 325 runs a Unichip mapped by Circuit Motors too, with exactly the same symptoms. Nice power and drive but drinks fuel and smells like a B plate fiesta.Did it give a power and torque gain? Do you have figures or a graph?
Both guys know where we are and I am here to help.
I've been meaning to but just been too busy. Plus it's not my everyday car any more so it's not as important. Will be back with you for a tweak next year though. It's away for the winter now and i'd rather combine fuel tweaking with a change of exhaust and intake to avoid having it mapped more times than necessary. Pushing 22mpg when it was on its last long journey though so not all bad. The bulb's gone in the OBC now so i can't tell what it's doing any more!
Or you might be mapping an M52b28 in it next year, not sure yet.
Or you might be mapping an M52b28 in it next year, not sure yet.
agent006 said:
I've been meaning to but just been too busy. Plus it's not my everyday car any more so it's not as important. Will be back with you for a tweak next year though. It's away for the winter now and i'd rather combine fuel tweaking with a change of exhaust and intake to avoid having it mapped more times than necessary. Pushing 22mpg when it was on its last long journey though so not all bad. The bulb's gone in the OBC now so i can't tell what it's doing any more!
Or you might be mapping an M52b28 in it next year, not sure yet.
Good good Or you might be mapping an M52b28 in it next year, not sure yet.
22mpg isn't too bad considering the way you drive it lol, but I'd expect a little better then that to be honest, maybe moving the TPS so you still had fuel cut off for engine braking may have upset the map more than I thought it might? Although I tuned the car leaning for economy before, I knew it was a track car mainly, so took that into consideration while mapping.Whatever you have under your bonnet, you know I'll help you out with the mapping mate.
agent006 said:
Didn't need to move the TPS in the end, just move the throttle stop so it would engage idle.
Ah, top job.Looking at Powerstations graphs, I would say the M3 is not running right. I suspect the engine has been buzzed as it was making over 260bhp on my dyno with around 190ftlbs torque. I have had other cars on my dyno from Powerstation an mine usually reads around 10-15bhp less than thiers. I would say now that Warrens car would probably only produce around 235/240 on our dyno now looking at Powerstations figures. It had around 220bhp at the wheels if I remember right time after time with AFR's around 13.2:1. With the car stinking frm behind and the fuel consumption being horrendous now, I would say something was amiss. That car ran very cleanly, crisp and Darren commented on how good on fuel it was a few months after the conversion.
The Merc 190 Cosworth is indeed mechanical injection. I wouldnt bother fitting a Unichip to that because of it.
Edited by ShepsM3 on Wednesday 12th November 20:48
If it helps anyone my 2.5 Merc does 28mpg all the time so Alec I'd hope your 325 could get close.
Oohh.. interesting.
Did it give a power and torque gain? Do you have figures or a graph? Warren who now owns the M3 has been planning on bringing it back to me, but I hav not seen it as yet. He's too busy cleaning it and taking photos.....
sorry just enjoying the m3 porn. He said he's going to bring it in as he wasn't sure it was 100%.
The 220bhp at the wheels - what gear's that in? Excuse the curiosity I've been reading Circuit Driver back issues while between jobs...
ShepsM3 said:
Pentoman said:
agent006 said:
Pentoman said:
Tiny bit stumbly from cold though. However it stank like a racing car when you followed and it was floored, and the owner said fuel consumption was horrific.
My 325 runs a Unichip mapped by Circuit Motors too, with exactly the same symptoms. Nice power and drive but drinks fuel and smells like a B plate fiesta.Did it give a power and torque gain? Do you have figures or a graph?
sorry just enjoying the m3 porn. He said he's going to bring it in as he wasn't sure it was 100%.
The 220bhp at the wheels - what gear's that in? Excuse the curiosity I've been reading Circuit Driver back issues while between jobs...
said:
The Merc 190 Cosworth is indeed mechanical injection. I wouldnt bother fitting a Unichip to that because of it.
Why?Edited by Pentoman on Thursday 13th November 16:56
Edited by Pentoman on Thursday 13th November 16:57
I havn't fitted a Unichip to a mechanical fuel injected car, although I would say your would benifit with just an ignition remap, I am unsure how we could map the fueling. I understand from the distributors up north that it can be done, but as the injection system is "mechanical" you will probably never get a consistent map from it?
220bhp at the wheels was in 4th gear with a warm transmission. Equated to around 261-265bhp and was over 195ftlbs torque (at the flywheel)
I'd be pretty keen on a run back on our dyno to see how it compares to when we converted it, as back then it proved extremely consistent and fuel efficient.
220bhp at the wheels was in 4th gear with a warm transmission. Equated to around 261-265bhp and was over 195ftlbs torque (at the flywheel)
I'd be pretty keen on a run back on our dyno to see how it compares to when we converted it, as back then it proved extremely consistent and fuel efficient.
ShepsM3 said:
Looking at Powerstations graphs, I would say the M3 is not running right. I suspect the engine has been buzzed as it was making over 260bhp on my dyno with around 190ftlbs torque. I have had other cars on my dyno from Powerstation an mine usually reads around 10-15bhp less than theirs.
Powerstation's bhp figures are a load of absolute cock to be frank about it. The wheel bhp numbers are far too low and the transmission losses far too high. Why they don't get it sorted out properly I have no idea. It must be obvious to them comparing data with any other rollers or am I crediting them with too much intelligence?It's very rare to come across a set of rollers which reads low on the wheel bhp numbers, which after all is the only thing that rollers really measure or can be calibrated to. The only other one I'm aware of is John Clarkson Autos in Chorley who have a Dastek system which I find are usually dead accurate. For some reason his also reads very low at the wheels and high on the losses although the combined flywheel numbers compare well with other data. I'm not sure I can say the same for Powerstation's flywheel numbers but don't have enough back to back data to be certain.
Although it's a subject I've studied for years and have written more about than just about anything else on my website I still don't see how you can set up rollers to read low at the wheels and high on the trans losses. The trans losses are simply tyre and gearbox drag measured on the same rollers but as negative numbers and if the rollers have been calibrated low then surely the wheel numbers and trans loss numbers should both be low.
One day I'll have to ask Gerry at Dastek what jiggery pokery it takes to achieve this but it makes it bloody difficult to compare such rollers to anyone else's. It also makes it impossible to use my normal trans loss equations which of course rely on accurate wheel numbers to produce reasonable flywheel 'guesstimates'.
Dave Baker
Puma Race Engines
ShepsM3 said:
220bhp at the wheels was in 4th gear with a warm transmission. Equated to around 261-265bhp and was over 195ftlbs torque (at the flywheel)
Those numbers look spot on. My own equations for a rwd car would give 220 wheel bhp as (220 + 10)/ 0.88 = 261.4 bhpNice to see a set of figures without absurd transmission losses
What type of rollers do you have there?
agent006 said:
Pumaracing said:
What type of rollers do you have there?
He's got a Dastek set.Good fun... its rare to find a dyno runner that doesn't criticize other dyno runners (this isn't me being mean, just a nature of the fact they are difficult to run I suppose).
The day was a vr6 o/c day so approx 15 VR6 Golfs ran - all made figures which seemed near to stock figures so I thought it was a relatively confident indicator. For me, I went to powerstation 2 years ago so was keen to go there again since I rebuilt the top end a year ago.
Back to my Merc... - the ignition does indeed have a computer. As for the fuel - yes injection is mechanical (a flap is moved by intake airflow, this flap is connected to a lever which when moved lets more fuel to the injectors). However it's KE Jetronic so there's an (electromagnetic) actuator which, when current is applied by the ECU, varies the fuel control pressure that the flap works against. Ergo it leans/richens the mixture. It will do closed loop but not on my pre-cat car.
The day was a vr6 o/c day so approx 15 VR6 Golfs ran - all made figures which seemed near to stock figures so I thought it was a relatively confident indicator. For me, I went to powerstation 2 years ago so was keen to go there again since I rebuilt the top end a year ago.
Back to my Merc... - the ignition does indeed have a computer. As for the fuel - yes injection is mechanical (a flap is moved by intake airflow, this flap is connected to a lever which when moved lets more fuel to the injectors). However it's KE Jetronic so there's an (electromagnetic) actuator which, when current is applied by the ECU, varies the fuel control pressure that the flap works against. Ergo it leans/richens the mixture. It will do closed loop but not on my pre-cat car.
Pentoman said:
Good fun... its rare to find a dyno runner that doesn't criticize other dyno runners (this isn't me being mean, just a nature of the fact they are difficult to run I suppose).
The day was a vr6 o/c day so approx 15 VR6 Golfs ran - all made figures which seemed near to stock figures so I thought it was a relatively confident indicator. For me, I went to powerstation 2 years ago so was keen to go there again since I rebuilt the top end a year ago.
Just to be clear I don't have a dyno. I do however seem to spend half my time trying to make sense of the figures they come up with for the engines I build, or at least did until I retired.The day was a vr6 o/c day so approx 15 VR6 Golfs ran - all made figures which seemed near to stock figures so I thought it was a relatively confident indicator. For me, I went to powerstation 2 years ago so was keen to go there again since I rebuilt the top end a year ago.
The VR6, at least the 2.9 engine, is not the ideal choice on which to conclude a dyno is accurate. The 2.8 certainly puts out close to its claimed 174 PS (172 bhp) but the 2.9's claimed 192 PS was just marketing nonsense by VW to try and distinguish the models and charge a bit more money. The engines are more or less identical barring the small overbore and all that gave them in reality was another 5 bhp or so. It was nowhere near another 18 as claimed.
On accurate rollers you'll usually see a 2.8 make about 140 at the wheels (maybe 170 flywheel) and a 2.9 a tad more. As I said previously the Powerstation wheel bhp numbers are miles out though so I wouldn't like to say what one would show on there. Probably something daft like 120 at the wheels and supposedly 180 or more at the flywheel.
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