Ran my car on a rolling road at the weekend

Engine mods are a Gtec1 Chip and a Supersprint pipe

Graph is here http://i32.photobucket.com/albums/d20/AFHpower/photo.jpg

Its pretty obvious that something is busted with the boost controller, as you can see the boost pulsing on the gauge

what are peoples thoughts? most likely its knackered and that I Should replace with a new stock one? or that the standard ones cant handle the boost and should replace with an uprated one?

appreciate any help

Did they not point you in the right direction for the loss of power? Not 100%, but could you be losing boost from a pipe somewhere, as this was a problem on my Renault 5 turbo recently and once sorted made a huge diierence!
Steve

Did they give you a boost and AFR graph?

What boost controller are you using?

maybe someone should put together a to-do and not-to-accept things for a RR session?
No offence to anyone, but many graphs appearing are difficult to interpret and/or not complete making the trip to the RR next to useless. I mean the idea is you go there, check your car and get some usefull feedback for sorting out possible errors. Unless you get all the graphs plotted, in the right units, do the run in 4th gear (typically) etc the results don't mean much!

Trappy?


V.

Starter for 10:

http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Number=304287#Post304287

getting too old I guess...

V.

i wouldnt worry to much about the figure, thats what my car made with a gtech1 and no other mods, depends on how many miles the turbo has done, it may be slightly worn, although sorting out your boost will def help

ok. So I have had a little investigation on the car today, had a really good hunt for boost leaks and all seems sound, checked the dv and it isn't leaking boost at all,

I took it out for a good spin whilst having an eagle eye on the boost gauge and it is now not holding as much as it usually would. It would normally hold 19 psi but seems to not even hold 17 and the needle on the gauge is shakier than my hands after 10 serious lattes!!


I ran the car on the rollers out of pure intrigue as part of a friends clubs day, I dissagree about the earlier posting saying the results aren't worth much, but it's told me all I need to know. The car Is down on power and something about the power delivery is wrong. I'm really not sure how a more accurately plotted graph or an a/f ratio would of helped me here. Unless the gtec chips are all different? I like to think i know enough about the Ins and outs of the rolling roads to decide whether to run my car or not, as I have run previous cars at the same place so I know how they compare with others, which I think is far more important than just the raw figures which in reality mean nothing

217 hp is pretty low with a Gtec1. I got 255 hp with a Gtec1 and a friend of mine got 259 hp.

Jeremy, what boost controller are you using? If it's the standard one then it could be faulty or simply need cleaning, or you could simply be suffering from the quite common Gtec see-sawing. Mine sufgfered from it terribly. If this is the case, then a £25 PRV would sort it.

The reason it was suggested that you should have asked for more on the graph is because it might help identify the low(ish) power problem. A boost trace will help you see where boost is building and show, a lot more clearly, where it is see-sawing. Your torque seems to trail off quite quickly, so although you say it was making 17-19psi peak, I'd like to know what it is making towards the redline. Again, a PRV would help a little with this and would give more power; torque at high rpms= high BHP. If you're losing boost, I'd think you'll be losing it at the top end more...

An AFR trace is probably the most important thing you should expect to receive from a dyno run. It shows if you car is running healthily and safely and can give an idea as to what mods you might need next to get it running nicely.

Although all Getc1s are the same (unless specified otherwise), different cars will get different results with them just like any other 'plug'n'play chip'. Some cars seem to make huge power on them, others only a little. Some run incredibly rich or lean. If you car is running rich, it might explain why you aren't running as much power as might be expected.

The boost controller is the stock item, an 99,000 miles old

I really dont want to fit a manual boost controller, as I rather like the idea that the ecu can cut the boost if there is something untowards

Next I want to try and fit a fresh, standard controller and see how that improves things, I tried getting the part numbers off my current unit, but it is corroded and I cant

Does anyone have the details of it? so I can source one?

Isn't the 20VT supposed to be 220bhp as standard?

Yes, 100,000 miles ago.

Give it a good service. When was the air filter changed?
Also the PVR can be set up as a boost limiter. that will stop spikes.

see http://www.armval.co.uk/images/bcv13config.jpg
and
http://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Main=53870&Number=669228#Post669228

HTH

If you're getting the boost pulsing problem with the Gtec1 I can send you a new chip with slightly modified boost maps which may help. Just PM me your address and I'll stick one in the post.