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Dyno results !!

896 views 17 replies 7 participants last post by  artfulmatt 
#1 · (Edited)
Hello peeps !!

Well had me car dyno'd at courtenays yesterday !!

first of all - the car only made 233bhp but it were only holding 12psi !!

After some investigation we put it down to wastegate creep as the boost only begins to drop at high rpm !!

they swapped (with no charge) my actuator which was a -2 with a -5 both are courtenay actuators.

I weren't happy with the power output - so we aimed to raise the boost, abviously we needed to know what the fuelling was like !! thats when I sh*t myself !! lmao .91 was the figure which is lean for a normally asperated car so raising the boost would have been stupid !!

We did check the turbo to see what boost pressure it created !! 18psi was it's max (standard KKK) so looks like she has seen better days.

So plans are to change injectors tp Z20 LET up the FPR to 4.2 bar, check fuel pump and wires !!

once I've done this back to courtenays and up the boost.

One impressive sign was the inlet air temp - the ambient temp was 22 degrees - and the inlet temp was 40 degrees, So I was very pleased with that.

Does anyone know how much a set of Z20 LET injectors are ???? ;)
 
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#7 ·
imcsherry said:
I wouldn't have thought you would get accurate power results on a 2WD RR running 18psi as you tend to get slippage on the rollers.

If you are interested I've got a set of cleaned & tested Bosch Red injectors for £80.
We weren't lookin for power results - we just checked the turbo to see what the maximum boost pressure was. A heathly KKK turbo should make 20psi + mine only made 18psi !! but it's the original turbo and has done 94,000 miles. It don't smoke either !! So I'm not that worried at the mo !! ;)
 
#9 ·
oxinez said:
How do you just test the turbo?
Well it's very dangerous so you've been warned !!

disconnect the wastegate vacum hose !! this way the wastegate cannot be opened so will keep on creating boost (sh!t loads of it)

this will cause the engine to run extremely lean !! so DO NOT TAKE IT UP 2 FULL RPM !! and test in very short bursts !!

Best to check on a dyno for safety as they can see the fuelling, but you get better results from the turbo on the road !! ;)
 
#12 ·
cambridge said:
lambda 0.91 ? thats rich. which is good

its approx 13.4 :1 :) maybe going to 12.8 :1 would be more ideal though
You are kidding me right? The ideal AFR for SAFETY on a turbo running 1bar of boost is more like 11.8/12.1. This can only be measured with a wideband lambda sensor as well.
If you have a intercooler/charge cooler I would expect 12 psi to return nigh on 260+BHP as well. Without it should be close to 240-245ish.
 
#14 ·
cambridge said:
not having intimate knowledge with turbo aplications i wouldnt knwo the ideal turbo afr. but for NA the 12.8 stands fairly well.

but the general point of 0.91 being rich is true.
N/A and turbo are completey different in terms fuelling. I would agree that 0.91 is rich but a std lambda doesnt really do a wise job past 13.1 in turbo applications.
 
#16 ·
artfulmatt said:
Using a foot pump to test the turbo ???

Ur confused with testing the actuator !! u can use a foot pump with a gauge and see what pressure it starts to open - it'a way to see if the spring is weak or not !! ;)
yeah thats the puppy. isnt that the same thing though ? finding the pressure that the wastegate opens = boost pressure ?
 
#18 ·
0ddball said:
on second thoughts of course it isnt, that would jsut find the actuator governed boost, not the max atainable.
Yep u got it !!

the actuator opens the wastegate to bleed any extra boost out through the exhaust !! so you only make what is governed by the ecu !! - why peeps chip the ecu to up the boost !!

without the actuator the turbo will just keep going until it's full stretch !! about 20 -22 psi on a KKK K16 !! :rolleyes: ;)
 
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