Unichip vs remap

[dr_mat 0]

Hi guys,

 

Thinking of getting Stealth to remap the VR later next month, to try and combat the pinking I've had since the hot weather got to the Schrick.. :(

 

They offer two services - remap the existing EPROM or fit a unichip.

 

Which is better? What are the pros/cons of each? The unichip is dearer (slightly) and I know it's a reversable mod, but is it better than a remap (or even as good)?

 

Cheers,

 

M.

[corradovr6sc 0]

The unichip can be reprogrammed so if you have future mods in mind such as cams it would be cheaper in the long term as you'd only have to pay for rolling road time. The unit can be removed and sold separately when you sell the car.

Not sure whether the map is any better or not but I've heard that when the unichip is used, the car is mapped to run rich and the unichip is used to lean out the mixture.

[Scruffythefirst 0]

Not sure how good VW ecu's are, but if it were my money I'd go for a live mapped new eprom. Not a rolling road eprom and the unichip just sounds like bad news. Remember running too rich will kill an engine just as quick as running lean.

[Kevin Bacon 5]

There's nothing wrong with a Unichip at all. I've seen good results from using one and it's cheaper and easier to setup than burning a new EPROM. Just because it's not a £1000 DTA or Emerald box, doesn't mean it's no good. It's just simple electronics at the end of the day.

 

The VW ECU is nothing to write home about. Take it out of it's protective casing and see what you get for your £500+VAT.... not a lot.

[dr_mat 0]

Hmm. Is the unichip actually mapped to the car at all? The more I hear the more I think the "better" solution is a EPROM remap, albeit with the obvious hassle of having to have it recooked each time a change is made..

 

So if I were to have the unichip fitted, Vince would modify the map for free with each future modification? How does that aspect work?

 

What about having a remap EPROM on a second EPROM - would it be possible to plug/unplug in the existing ECU if I went back to standard at a future date?

[Scruffythefirst 0]

Isn't a new eprom just a chip? Ie once you've paid for the original chip all you need is the rolling road time and then burn a new chip - which should cost less than £10 and it should just slot in. With cosworth ecus (magnetti marelli) once you've unsoldered the chip for the first chip, changing to another chip takes 10 seconds. They cost peanuts to burn - you can do them from your home pc easily enough

[dr_mat 0]

Hmmm. The "new eprom" seems to be advertised at £350 a shot. I know as well as you do it's an easy job to flash a chip, but getting someone to do it is the hard bit...

 

What I'm looking for is the ability to put the car back to standard - i.e. standard manifold, standard chip. What would be ideal was a new EPROM that works well with the Schrick *and* works equally well with the standard manifold. I doubt such thing exists... :)

 

And running rich, even for a few weeks, sounds like bad news for the CAT....

[Scruffythefirst 0]

When you get it chipped, just ask to keep the standard chip, or if it gets damaged removing it, get them to burn you another standard one and then it should just be a case of removing the schrick and poping the original chip back in. Chips are generaly over priced because soemone had to put a car on the rollers (or road) and map the new fuel requirements. They then whack the price up, your much better off spending the money on rolling road time and getting a chip for the same price as you would have paid, but suited exactly to your car.

 

The uni chip sounds like a good idea, but isnt any cheaper than a eprom from a good rolling road which works in the way the factory intended.

 

Theres also no real need for a aftermarket management unless you need extra load points, running soemthing so different to standard that you have no choice or you really know what your doing and have all the associated kit to go with it (wideband, det cans etc)

[dr_mat 0]

Do they fit a chip holder in the ECU? If so, that sounds like a good plan - cos then as you say it's just a case of using a chip puller to switch EPROMs. Maybe I need to talk to the man who knows about all this, Vince...

 

Now, on another subject - where's the best place to get the VR6 steering rack from? Preferably genuine, and preferably not refurbed... :(

[Scruffythefirst 0]

Do they fit a chip holder in the ECU?

 

They should do, if they dont go soemwhere else. Cant see why you'd want to solder in a new chip and risk cooking it when a chip holder costs sod all, plus you only want to do the soldering once.

 

On the rack - no idea :D

[warcraft 0]

Hmm. Is the unichip actually mapped to the car at all? The more I hear the more I think the "better" solution is a EPROM remap, albeit with the obvious hassle of having to have it recooked each time a change is made

 

unichips r great, yes they r mapped to each individual car.

then when u add new mods u just have the map tweaked to suit.

 

I had them on both of my pulsars, i found that the cars ran better throughout the entire rev range, especially the midrange area.

 

(sorry to dig this out again, just going thru some older posts)

[dr_mat 0]

unichips r great, yes they r mapped to each individual car.

then when u add new mods u just have the map tweaked to suit.

 

(sorry to dig this out again, just going thru some older posts)

 

Actually I should have updated this thread myself: I had the unichip done, see.

Well the pinking's gone, and my mid-range torque has benefitted hugely (199lbft @ 3630 rpm). Running is good, but it's too early to say if that's due to the chip or just cos the car is in a good mood.

 

As you say, the flexibility of the unichip is cool. Plus, one day when I'm flogging the car on, it can be reverted to standard just by putting the OE manifold back on and unwiring the unichip, both of which can then be sold on as a package. This aspect appeals to me, definitely the best way to protect my Schrick investment!

[dr_mat 0]

And here's that nasty torque curve... :)

[dr_mat 0]

Spot the effect of the Schrick, eh?! :twisted:

[MoonlightVR 0]

Impressive stuff Matt

[jedi-knight83 0]

thats wierd....and thats after the uni chip?? how come your power is so low and look at the size of the flat spot after the schrick kicked in!!??

 

It makes my plot look even wierder now!

 

MY PLOT

[dr_mat 0]

Scaling issues... Your plot looks about the same, just less obvious due to the scale...

The two torque curves on there are before/after the unichip was fitted.

"power so low"? watcha talkin about mate?

[Kevin Bacon 5]

That's before and after torque, no power on that graph.

 

Stealth's plot is more detailed than yours, which is why it looks different. Yours has been "smoothed off" considerably by software.

[jedi-knight83 0]

ah...i presumed that other figure was power..... so..your schrick only made 185 lbft at 5594rpm before the uni-chip... :?

 

agreed that stealths looks more detailed...but its still a pretty big drop and im sure mine wouldnt have just 'smoothed' out the drop??

[Kevin Bacon 5]

His was marred by pinking, which kills the torque.

 

Yours has been smoothed off for readability, Matts is exactly what the dyno saw.....

[dr_mat 0]

Every detailed VR6 plot I've seen looks like mine does above. (Certainly the bit above 4krpm where the Schrick isn't really doing any tricks.) The pinking was killing off the whole midrange on mine beforehand. It would pink really badly between 2800 and about 3500, then because the ECU had noticed all the pinking and really really backed off the timing, I wasn't getting the normal 4krpm surge either. Hence the 185lbft!

With the pinking dealt with by some judicious fuelling and a bit of additional ignition retard, it's pulling like a train, and you can really feel the shape of that torque curve when you let it pull through in-gear, as I'm sure you can on your car too.

I'm pretty pleased with 199lbft on a 122k miler VR6, and I don't really give a monkeys that it reads "only" 199.6 bhp, cos I never go above 5k rpm anyway..

(And anyway, that 199.6 is moot, given that it's a dodgily predicted @crank figure based on approximated transmission losses...)

[Kevin Bacon 5]

I'm pretty pleased with 199lbft on a 122k miler VR6, and I don't really give a monkeys that it reads "only" 199.6 bhp,

 

Hear hear....

 

199 power with 199 torque is perfect.....shame it's not quite linear all the way through :lol:

[jedi-knight83 0]

so i wonder what a unichip would do to mine if im already getting 196lbft at 3900rpm?

[Kevin Bacon 5]

You won't get a signifcant improvement on that unfortunately.

 

If you want more, you're going to have to slot some 268s in :lol:

[dr_mat 0]

Jedi - when my Schrick was first fitting I was reading 195lbft, but after the ECU leaned off the mixture and "adapted" ( :roll: ) it started pinking and it really dropped right off.

Hopefully it'll stay as it is now that the chip is compensating for the standard map's shortcomings...