rob82

How rich was it and how retard was the timing are the two questions I would be asking?

The 350z is a 36 minus 1 I think. We started with the 6-5-4-3-2-1 CAS signal and never followed it up. If there is enough interest, who knows. The xede doesn't drive the coils directly like the emanage. However I heard of several damaged coils in skylines with emanage. The xede is a very proficient boost controller. With the fords we use the output of two maps to determine what wastegate DC is. For example a Wastegate DC vs Map vs RPM and a Wastegate DC vs TPS vs RPM. Its semi closed loop boost control. The xede also has a switch that can change entire maps on the fly. The list just goes on and on.

It is a piggyback unit. http://www.xede.com.au/ Its alot more functional as you can choose the map axis and also use multiple map for complex functions. If you want more info just let me know and I'll get the xede training day presentation.

We are having problems with the nissan crank angle sensor. But I think also that the market for the xede on skylines just wasn't there. However I have been talking to my boss the technical director of the xede and he said if it can generate enough interest with the nissans then he would go ahead and develop it. What do you guys reckon?

So how long is your gearbox going to last? Not taking the piss honest question.

Have seen them play havoc as well with standard computers ie poor grounding/wiring leading to wrong voltage bias on narrow band O2 sensors. Its always cool when the standard computer is trying to trim the wrong amount of fuel in or out. We use this ability of altering the 02 sensor bias with our Xede processor to enable a lean cruise function(with the right conditions of course).

Raise the compression!!

That does seem a little high(210rwkw) did they strap it down or at least put wieght over the rear. We usually see between 185kw-200kw. I tuned a typhoon the other day 330rwkw at about 15psi and about 920N.m of torque at 4400 rpm.

Lots and lots of line pressure uprated clutches etc etc you would have to talk to an auto guru. Usually the higher the hp the higher the stall (the greater the slip). Simply answer no.

You can run a car in any gear and it should give comparable horsepower readings. ie a manual R33 should give about the same power readings in 3 as it would in 4th within about 1-2% depending on the dyno operator. You must remember that dynos measure the rate of acceleration under a specified load and Horse power is a function of Torque and RPM so while lower gears will give a higher torque than a taller gear the RPM of the rollers is less in the lower gears than the higher gears. Now dyno dynamics specify that their dyno's are accurate between about 80 -140km/hr. So the aim of the dyno operator is to choose a gear that will rev between these points.

Yes - if you cant get a chip.

Ever seen a 2000hp drag car on the dyno - they usually make about 3/4 of that value. To much trans slip to give accurate readings not to mention changes in auto trans fluid temps(varying viscosity etc etc) not good for dyno comps or tuning at high levels of horsepower.

Dont waste your time with a piggy back if there is a good stand along compter like the PFC, the other option is a Chip and thats the only two computers apart from an autronic that I would use on a GTR.

In dyno dynamics shootout mode the ramp rate is fixed for 4,6,8cyl and 4,6,8 cyl forced induction plus a few others 2R 3R 4X4 ect ect. The reason that strapping is essential in comparing graphs is that if the car is allowed to torque up onto the front roller it is therefore not spinning the rear roller hence faster acceleration rates; hence more power and torque. A properly designed strapping system should force the tyre into the roller more and more as the torque increases rather than just forcing the tyres down.

He may have missed that the throttle was not closed when he checked the timing. To set the static timing the ECU must register that the throttle is closed and that the engine is up to temp ie above 80deg. Once these two conditions are set that timing should be 15 deg. Now if he adjusted the timing with the TPS not registering closed throttle the timing numbers shown on the timing gun would be around 18 - 20 deg in which case he may have retarded the timing 3deg which is more than enough to cause a miss. If he thought it was idleing to high he should have adjust the IAC bypass valve not the timing. Alot of people dont realise that retarded ignition timing can cause a miss fire event.

Your tuner doesn't have a clue, 20 degrees into an ls1 - bullshit!!! I chip at least 5-6 LS1's a week with various levels of tune and I can tell you that if he is adding in 20 degrees more at any point on a standard DFNN or DSKW file than it will rattle.

If your advancing the timing over 20 degrees and your motor is still together then something must be wrong ie- your static timing number must be overly retard alot or your compression is like 6:1. This whole comparing knock figures is bullocks. Different motors, different sensors different knock levels. Do you guys realise that its unlikely under light to medium throttle that you will not hear a knock event without a chassis ear. I've found by a rule of thumb that base PFC timing maps to be very sharp with 2-6 psi of boost on board between 2500 - 3500rpm. I know its temping to fiddle but if you go to a reputable tuning shop you shouldn't have any worries about your tune; hence pay the extra and be happy that its right.

sorry to be like this but your wrong 15 years as an instrument tech the afms meter works on air speed (cooling) so as long as you keep it near the centre of the pipe it will work fine. There nothing special about the z32 afm meter and if your running a pfc you can install a custom ramp graph for the afm meter and will not even need to adjust the maps(spark and fuel). Good to see someone willing to try some thing and not just be a sheep. my 2c So in your 15 years did you ever stop to think that maybe if you change the diameter of the MAF housing that you would change the air speed of the incoming air; hence changing the cooling affect. It seems you have missed the point I was trying to make. If you increase or decrease the diameter of the MAF then you must readjust (usually within the MAF transfer table) the voltage to airflow charcteristics. CEF11E has sombody who can tune it for him cheap, so I would say go for it, he's got nothing to lose. However I wouldn't suggest this modification to anybody who isn't in the position of buring up 5hours of dyno time to get it to the same level as a z32 MAF. Also the standard computer has a higher resolution MAF calibration table compared to the PFC which will make it more bearable than the PFC

Voltage vs Airflow their is very little difference between the Z32 and the nismo items so either will be fine for your application.

Voltage vs Airflow their is very little difference between the Z32 and the nismo items so either will be fine for your application.

Hmmmm if nissan couldn't do knock feedback timing above 4000rpm what makes you think that a PFC can distingish between engine noise and a detonation event? Your tuner should no what real knock is by listening to the engine with or without a chassis ear not to mention NOx levels going through the roof. I know it might sound like an amazing thing but knock levels will be different for different cars/engines all this comparing knock levels is BS.

How long did you drive it with the miss? From what you have described I'm still suss on the head gasket. Did it have this problem before the miss occured? Perform a leak down test and check for the coolant bubbling.

Lets remember to that 400whp US isn't 400whp AUS its probly somewhere around 330w hp so around 250rwkw. Its not to excessive power wise considering their 93 octane fuel. Check your coil's dude. Your miss at idle is probably due to you plugs being gapped so low. If you need a 0.6mm gap its time for CDI.

Hmmmm 5hours of dyno tuning at $200/hr for a 20kw increase in peak power while losing low to medium load drivability and perhaps usable torque, possible shit idle stability(due to loss in low flow resolution) and more common stall events. Thats everything 1 want in a $5 dollar PVC pipe. I dont mean to be pessimistic but there is a reason that car manufactureres spend millions upon millions on designing their sensors. There is no reason at all that the standard ECU isn't up to the job its just a matter of using the right parts for the job and that would be the Z32 MAF. Your probly only looking at 1-2 hours on the dyno to tune a Z32 MAF.

The ratio of diameter to airflow isn't just as simple as what SK said if you increase the diameter from 80mm to 90mm thats not exactly 27% more flow as its area is 27% larger, its much more complex than that, this is why MAF tranfer tables are expotential not linear. That said your not dealing with a frequency based MAF so that approximation should get you somewhere close. I have had alot of expereince tuning different MAF's for different cars including nissans. The problem with nissans is that there is not enough serial data you can compare you MAF transfer table to. This is because the maths behind the nissan computer is based on injector pulse width not desired air fuel ratio. To get an idea of where the MAF table is going would be to watch your trim numbers in closed loop and modify the table until there is zero trim which is 100% on the nissan consult. Please understand that this is a big job for a chip tuner. You have to weigh up if it is worth the extra money spent on the dyno just to tune your experimental MAF or go with something that will just work like the Z32.