4396 replies to this topic

[CHILL Gone DUTCH]

when I'm back in the UK I will be able to get some work done on mine, worth booking joint dyno time Chill have you looked at my runs? can't access any here

Nick I've just started looking at some of your files and it's uncanny how your getting a similar dip at exactly the same place but maybe not as dramatic

[CHILL Gone DUTCH]

 

when I'm back in the UK I will be able to get some work done on mine, worth booking joint dyno time Chill

have you looked at my runs? can't access any here

Nick I've just started looking at some of your files and it's uncanny how your getting a similar dip at exactly the same place but maybe not as dramatic

 

 

example 

 

 

 

mine is coloured line nicks is grey line

 

Edited by CHILL Gone DUTCH, 10 May 2015 - 03:43 PM.

[CHILL Gone DUTCH]

the most interesting thing when comparing our runs was the boost pressure and ignition setting considering the power lines and torque line are comparable

 

 

just goes to show the the small pulleys are producing more boost but not necessarily more power  

[CHILL Gone DUTCH]

However Nick you do have a lot of knock retard going on here And your wideband is not working yet

Edited by CHILL Gone DUTCH, 10 May 2015 - 04:08 PM.

[Arno]

Isn't an increasing boost pressure vs. rpm on a roots style blower an indication that the engine is not 'consuming' the air it's fed by the constant-displacement of the blower and it's volumetric efficiency is basically insufficient to process the incoming air at increasing rpm?

 

As the power levels between both engines are roughly the same that would seem to be correct. The added air by the faster-spinning charger is simply wasted as (static) pressure but not being used by the engine to make power.

 

Has someone ever put a Z22SE or SAAB head on a flowbench to see what it can/should flow and wether or not porting work or larger valves would help to get more air into the engine?

 

Bye, Arno.

[CHILL Gone DUTCH]

I've also done some comparisons between me and Luke again he is on a small pulley but he has bigger valves and ported head on inlet side

[haggi961]

Plus I dont have the ls4 fitted in the graph.

[oakmere]

The fact Luke smooths the dip out may point to the better flowed head and bigger valves working better. not worth spending all that money to get rid of that dip that can't be felt on road though Chill.

[CHILL Gone DUTCH]

Do you think the extra boost could be helping to smooth the dip ??

[vocky]

Has someone ever put a Z22SE or SAAB head on a flowbench to see what it can/should flow and wether or not porting work or larger valves would help to get more air into the engine?

the Saab cylinder head can be opened up quite nicely, but it does take a serious amount of time to do 

 

This is the exhaust port size on my NA head, the black paper shows the size of a standard z22se exhaust port 

 

[NickB787]

I ported my z22se head mainly inlet side, Saab valves not oversized. that was the first run I did on the ls4 just to have a look, I have changed the wideband since then might get that Saab head out which I have got sat at home and get porting, real pain of a job though, could be oversize valve time. did you notice the inlet temps on mine and Luke's, both are ported heads yet yours seem higher Chill on an OEM Saab unit

Edited by NickB777, 10 May 2015 - 06:11 PM.

[CHILL Gone DUTCH]

I ported my z22se head mainly inlet side, Saab valves not oversized. that was the first run I did on the ls4 just to have a look, I have changed the wideband since then might get that Saab head out which I have got sat at home and get porting, real pain of a job though, could be oversize valve time.

And maybe bigger pulleys

[NickB787]

note my edit about temps

[CHILL Gone DUTCH]

note my edit about temps

Yes I spoke to Luke and a few others about a theory I had about inlet temps and flow I suppose sharing all this data will help a little with inlet temps and picking a pulley to suit

[NickB787]

one of the thing I intend to do is change the pulley size both smaller and larger, just takes time to map the thing. I suspect a larger pulley may be better in the long run as Peter has said.

[CHILL Gone DUTCH]

Do you and Luke have the same cams

[NickB787]

I am on Comp blower cams

[CHILL Gone DUTCH]

Nick were your runs done in 3rd, I know Luke's were done in 3rd

Edited by CHILL Gone DUTCH, 10 May 2015 - 06:37 PM.

[NickB787]

No second gear

[CHILL Gone DUTCH]

Wonder if 3rd gear runs help to Smoothen the graph