Bambam7

Well, I finally was able to G-tech my car... I have the Air pump removed, so my VDI isn't functional right now (I will figure something out...), and I wanted to see what kind of difference the high and low positions made..... it sure does!!
With the VDI in low, it was a much stronger midrange, and shifting at 8000 is best. 0-60 was consistant, about 6.3 sec, and the 1/4 was consistantly 14.8 or so at about 95 mph.
With the VDI on high, midrange was noticably weaker, it required a 6000rpm lauch, and shifting at 8500. The high end was MUCH stronger though. Best 0-60 was 6.16 sec, and best 1/4 was 14.60 at 99.8 MPH. Every run with the VDI on high was about .2 sec faster than with it on low, but the MPH was always around 99, up from 95 with it set to low.
For driving around town, it is much better in low... but for full blown racing,(for my high RPM engine anyways) it is better in high.
I am still in DESPERATE need of 550cc or 680cc injectors and a TII fuel pump though.... It is gettting REALLY lean abot 6500. It stutters a bit, and somtimes conks right out for a second if I'm on the throttle near redline for more that 15 seconds or so.
I know I can get down to under 14 sec once I get the approriate ECU upgardes, and a stronger fuel system! This is the last time I want to see that high range untill I get the injectors.

With trap speed that high I should be getting better times, but I have to get the hang of launching- It's hard with an engine with a torque curve that straight goes up like a bullet- now low end. Plus I have bald 205 no names. I need traction bad!
ANyways, hope the VDI info is helpfull to sombody.

robx7fcna

WOW!!!! I envy you!!!!! LOL 14's in a na without the aid of any forced induction, that is pretty impressive. I hope I can break intothe 14's next year in my gx, but first, I better work on the 15's, LOL!!! I should be close now since I did a 16.1 @85 with these mods;
Pacesetter header
e-fan
no cats

Now I have added a k&n cone and noticed a power increase so I hope I can do a 15.8 or somthing like that...


I would try to take your car to the track though as you might get
a little slower time since the track has a different way of timing the 1/4 mile (somthing about putting an average time together on all your times (eg. 60ft, 110ft,1/8,1/4)Can anyone explain???

tesla042

The track simply times you, start to finish.. It will give you your REAL times. The g-tech can't really do that.. It has to integrate your acceleration to get your speed, and integrate that to get your distance.. Therefore, inaccuracies are bound to pop up, since it's sampling time is finite. It very well may pull tricks such as using your other times to get your 1/4 mile. It's not completely accurate as compared to a real track time, but as long as you're using the same g-tech for two different runs, you can compare THOSE numbers.

-Tesla

Bambam7

Ya, whether those are my absolute 1/4 times, I'm not sure, I know I can kill stock and modded(a little) tii's, and beat Mustang 5.0's, old and new(4.6), but I am just using the times by the Gtech as comparison with each other to measure the difference made by the VDI.
I would love to take my car to the track once I can fond a clutch that doesn't slip, and some bigger injectors- I am not racing anymore until then, It's too lean. I have put over 5 grand (Canadian) into the engine and car.... I don't want to blow it!

mazdaspeed7

Wow...thats pretty impressive. Next time I go to the track, maybe this week, but for sure by next week, I plan on trying the same thing with my car.

I really want to go to a full 1/4 track, but theres not one close to me. Theres only a 1/8 mile track.

Bambam7, just curious, have you ever raced a 300Z TT? I raced one a while ago, and only lost by a car and a half, 0-100. The 300Z was completely stock, except for intake.

pp13bnos

iTrader: (1)

Just think what you could turn if you had a working VDI. Bet your times would drop even further. CJ

t_mak@mail.plymouth.edu

Correct my ignorant, but what is the VDI high and low stuff?

t_mak@mail.plymouth.edu

Is there anyway I can disable my VDI easily (without removing air pump and stuff) I want to see if my VDI is working properly

mazdaspeed7

What year is your car? Only the 89-91 n/a's had it. Theres a actuator with a vacuum line going into it connected to a rotary valve inside the intake manifold below the plenum(the part of the intake manifold that the TB bolts to). Just disconnect the vacuum line. You wont have a vacuum leak, the actuator uses positive pressure from the air pump.

Xentrix

my vdi works but I dont have a manual handy

is it possible to port it so more air flows when it opens?

PaulC

OK I have a big question here. The best time I have run is a 15.06@83mph in my NA (and I have hardly done anything beyond exhaust to it) at the Texas Motorplex in Ennis. They run national events there for the big boys of drag racing so I know their equipment is right. So what the hell do I just have a freak car that ran great? its developed problems the last couple weeks so my 15.06 wont be duplicated soon.

PS no I didnt red light.