pcmhacking.net

Oh sorry, that was before the turbo went on and yeah 980kg. I Think stock

well I have been liaising with VL400 and trying to work out ways to run my twin 044 pumps only on boost....

initially started with a pwm interface to slow them both, but ended up frying that, I have a feeling that was my fault, either way it wasn't real successful, so then I tried 25amp solid state relays, these actually worked perfectly from a controlling the pump point of view, but after about 10 minutes of running they were red hot and subsequently supplying full power to the relays all the time even with the motor and ecm turned off!!

found out later they are supposed to be mounted on a big heatsink!!

so in the interest of keeping things simple going 4hrs from home to race next weekend I decided on using one pump on all the time and then have the second pump activated via a normal relay and the flex table, so I've set it to turn the pump on above 107kpa and over 3500rpm, this is usually well before I hit full boost (4000rpm ish) and its usually only higher in the revs I see a major drop in pressure....

either way I can adjust the on settings If needs be, and at least if I see a dip in pressure before the second pump comes on i'll know its making a difference!
so the lift pump and one of the 044's come on with the ecm control, then the relay for the main pump also provides power to the second 044 relay, but then the ground side of that is only on when the flex output commands it, so this way I have flex control over the second pump and also safety in that if the engine stops it will cut them all off, as well as making the flex not active unless the engine is running.

while I was at it I re-wired the whole lot (it had been cut and changed a few times with all my trial and errors) so I have gone for oversized 10 gauge wire from the battery through fuses and to the pumps so i'll never have a lack of power there!

soo, day one of gunnedah ... nothing broken, woohoo!!

got 3 runs, only real issue i had was the breather on the trimatic is blowing some fluid out, so put a rag over that to stop it going everywhere under the car (its only a few drops but enough to be an issue if it got on the tyres!)

so on that note got an under car video and the camera was covered in oil!! suspension seems to work a treat so really happy there!

[youtube]http://www.youtube.com/watch?v=UPTDqob_9T8[/youtube]
i think im getting some traction issues off the line, steps out a bit, and the you can see in the under car vid, leaves a black mark behind the wheel at the start, but generally went great

i did get a mate to video from the side but hes gone home and i didn't get the footage of him yet, but i did get plenty of in car vids!

these are 1080p 60 frames/sec its interesting to see the refresh rate on the wideband gauge!

got 3 runs and did 7.8 @ 150kph, 7.6, 7.6 for other two runs but speed was fucked so not sure whats going on with their timing! anyways, this is the 3rd run, botched the 2 step off the line but was a good run none the less!
[youtube]http://www.youtube.com/watch?v=9w70ghj8BOM[/youtube]

sounds like shes humming now

gee you can see the front of the diff dropping when the load is off! is must have been so much worse with the old suspension.

converter is still stalling too high and i reckon im loosing a bit off the line from that but otherwise yeah it is going sweet!

yeah i wish i had a camera under there before the new control arms went it ... although it would probably scare me what it was doing!!!!

oh and with the second pump running its holding a perfect 66psi from the start of the run to the end! so obviously the pump was a major issue!

sweet as!

Holden202T wrote:converter is still stalling too high and i reckon im loosing a bit off the line from that but otherwise yeah it is going sweet!

been looking at the logs and the under car video and i reckon its getting a bit of wheel spin off the line now and thats half the reason its not lauching as good as it maybe could, it was stalling to 4480rpm when i launch and thats where the speedo starts to move, so that makes me think the converter is pretty close to the right stall, but it definately moves the bum to the left for the first 20 meters or so!

heres some more vids from today, managed to get down to 7.4 with a 1.7 60 foot time, that seems to be the best improvements i've made! before i had boost off the line i was doing 2.1 60 footers!

also a video from behind the car, shows it getting some wheel spin off the line so theres probably more in it with some traction!

[youtube]http://www.youtube.com/watch?v=SG_ykTkRIxk[/youtube]

[youtube]http://www.youtube.com/watch?v=Jqp91j97vwk[/youtube]

all in all great weekend, unfortunately eliminations got rained out but got plenty of time in the car with no issues!!

also the second fuel pump has made a good difference, able to hold 66psi fuel pressure for the entire run!! it was droping to about 45-50psi before i think so thats good!

Good stuff, it certainly is coming together now!