Regarding Sluggish Engine Response Below 2000rpm

[B1ack_Mi16 67]

It's again the 2.3 litre, my wideband lambda is broken and I was off with the head etc. so I guess the mapping is not exactly 100%.

 

However is it too much to hope for to get a nice throttle response from low revs when I floor it?

 

The camshafts are rather lairy so I realise it's probably never going to be perfect at those revs.

It's like 3.5mm lift @ TDC on both cams, well 3.80/3.25mm to be specific.

 

As it's mapped these days it'll more or less "die" for a second or two if I floor it hard between 1500-2000rpm, better if I don't floor it so fast but still quite jerky until it reaches 2500rpm ish.

[DrSarty 90 1 Cars]

I hope it's possible to get this sorted. Perhaps it is the cams and/or mapping, but with my milder cams (1mm lift less than you Iirc) with Emerald's and Sandy's mapping I have no issues whatsoever. Could it be solved by staged injectors?

Edited July 23, 2010 by DrSarty

[B1ack_Mi16 67]

I hope it's possible to get this sorted. Perhaps it is the cams and/or mapping, but with my milder cams (1mm lift less than you Iirc) with Emerald's and Sandy's mapping I have no issues whatsoever. Could it be solved by staged injectors?

 

It's this hesitating that can be hear about 1:10 in this video.

 

Can't imagine staged injectors will do anything for that because it idles nice and stable at 900rpm and seem quite ok. Probably just an effect due to cams, inductoion and exhaust combination.

My mapper have lots of years experience but was not able to get rid og it.

 

However I'm starting to think it's just how it will be, didn't realize you had that much lift @TDC on your cams, I thought they were fairly mild.

 

Mine have 12.45/11.8mm maximum lift, I guess that's a fair bit more than yours then?

 

Anyway the engine certainly works, I was dragracing 100-200km/h this weekend with a 205 2.0 16v turbo that was dynoed to 270bhp, and we were running more or less 100% equal side by side all the way from 100-200..

 

That's' like 62 - 124 mph ain't it.. however his car weights a little bit more than mine so not a 100% direct comparasition..

[petert 589]

That's a fair amount of overlap and a lot of reversion. How much mapping have you done in that range? Can you add more ranges, say at 1750? Does it do it in every gear?

[B1ack_Mi16 67]

That's a fair amount of overlap and a lot of reversion. How much mapping have you done in that range? Can you add more ranges, say at 1750? Does it do it in every gear?

 

Can't add more ranges yet, but will be after I get the ECU upgraded to K3.

 

Long time since it was mapped now though, really need to get the innovate lambda working again to gain some more control.

 

The problem is however that it's hard to map it at low revs, due to the lambda values are all over the place, so not easy to know what to map it after.

 

When I was experimenting last time the lambda worked I remember AFR of 17 and 18 was perfectly at those revs.. indicating quite a bit of fresh air blowing by straight from the inlets out the exhaust.

How are professionals mapping engines with this kind of camshafts in low revs? I kinda feel I just have to do a lot of trial and error I guess.

Edited July 25, 2010 by B1ack_Mi16