Discussion
with DMS...eliot said:
Well apart from optimising the mixture perhaps - i dont see how chipping a N/A car can be made to provide any significant gains. I notice chips tend to raise the rev limiter - so your peak BHP figure rises a little, so all you are actually doing is thrashing your engine more? - no?
Cos manufacturers have to make compromise the maps
They have to meet noise regs at certain speeds (engine rpm and gear related)
(they engineer in a hole in the power curve - less power less noise)
They have to tailor the maps to run with a huge fuel octane rating variation
(from manky US parafin grades to V-power)
They also have to consider engine life (with long life oils)
(So are conservative in the ign advance maps)
They also fine tune the maps over the production run
(so sometimes later engines get better maps)
They also have been knownn to make the BHP figures fit the cars position in the range
(De-tune to create a suitable differential between a modern 4.4 V8 32V and a old skool 5.4 V12 24V engine)
Chipping can give very good gains with very little downsides
Oh and raising the rev limiter does not increase peak power unless the rev limiter was placed at a point before peak power was reach to "cap" an engines power output
Edited by B'stard Child on Monday 15th January 22:56
Generally most generic chips tend to lean out the mixture a bit and chuck a couple of degrees of timeing at the engine. On N/A cars, Sometimes it works, sometimes it does'nt (I've done countless before and afters that have made sod all difference)
Every engine is different, so you cannot just chuck a generic chip at a whole specific model because some engines will be fine, some won't. I would'nt let a generic chip near one of my cars unless it was adjusted to my specific car on the dyno. One of the reasons that despite being offered them, I flatly refuse to sell them.
The gains on turbo cars are much more proven, however, the problem with different engines taking different amounts of timing are still very obvious... Its a bit of a lottery really.
Bespoke maps, although expensive, are the way to go
Every engine is different, so you cannot just chuck a generic chip at a whole specific model because some engines will be fine, some won't. I would'nt let a generic chip near one of my cars unless it was adjusted to my specific car on the dyno. One of the reasons that despite being offered them, I flatly refuse to sell them.
The gains on turbo cars are much more proven, however, the problem with different engines taking different amounts of timing are still very obvious... Its a bit of a lottery really.
Bespoke maps, although expensive, are the way to go
This may offer some more insight:
www.pistonheads.co.uk/gassing/topic.asp?p=1&f=66&t=306655&h=0
FWIW, i find running several tanks of 98/99 through it in succession improves performance - I guess from the the lack of knock and therefore increased timing.
I would want to see a back to back test before and after personally - not convinced a few bhp are worth chasing.
www.pistonheads.co.uk/gassing/topic.asp?p=1&f=66&t=306655&h=0
FWIW, i find running several tanks of 98/99 through it in succession improves performance - I guess from the the lack of knock and therefore increased timing.
I would want to see a back to back test before and after personally - not convinced a few bhp are worth chasing.
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