Hello, i read this forum from some time and i have done some modifications on my G . Since i live in Bulgaria where G35 and 350z is not common for racing/track days i experience allot of problems tuning it. Got coupe of questions that i can't find answer by my own and will much appreciate to get some advice from PROS

car: g35 6mt brembo brakes 2003/vq35de/
Parts added:
short ztube intake
plenum spacer 5/16 motordyne
hks dual catback REPLICA
stage 2 XTD clutch kit /yes i know, i go true hell till i make it work lightweight flywheel ... make gearbox sound like crap on low rpm /
DBA XS brake rotors + ferodo racing DS2500 + replaced brake lines 6mm (maybe i have to take new 3.2mm for easy pressure achieving)
HSD monopro /full coilovers/ springs F-12kg R-7kg
megan racing front/rear camber arms

1: Here come my 1st problem local dyno/tuning "TST racing" never done a 350z/g35 and can't tune it so i only make few runs to see what output car have (close data since papers are not in front of me right now) ~4200 rpm 305NM and ~6400rpm 227whp. Good part - graphic of NM is almost straight ~280 on 2000rpm and goes like that till the end. I believe it is dynocom i run the test on. Looking around the numbers for G's seems to be higher? Only thing i come out with is i run the test with brand new Denso iridium (car feel somehow odd) now i swap it to NGK. (test was made in 6th gear i saw somewhere tests on 4th is it any difference ?)

2: Currently using 225/40r18 245/40r18 Kumho XS (on stock 18 rims) going to swap to 245/40r18 Kumho XS front and 275/35r18 michelin Pilot Sport PS2 ZP rear. Is it the right size choice ? What is better 8,5F and 9.5R or i can run square set up of 9.5 ? What ET is best for tracks i got choice from 8,5 et30 9.5 et35 ultralight from supra and 9.5 et 30 p45R all around (can put flanges)
advice pls.

3:Just received my new HSD monopro /full coilovers/ awaiting rear and front arms this days to start the swap. Here comes big questioning for settings. Right now /stock suspension/: 0 front toe FR 1.3 camber FL 0.4 (do not know why is like that but can't be changed...) rear camber 1.4 and +1.0 toe (0.5 by side). It handles pretty well according times it gives on track. Do i have to go front 1.5 camber and rear 2.0 since it eat my front tire outer edges? or i have to go for front 1.0 and leave 1.4 rear since stiffer suspension. What high ratio front/rear i can stick to ? Tracks i drive to is narrow , twisted can say slow average speed. + have in mind i drive this car not only on tracks

Any advice from personal experience will help me allot

 

If you're having trouble tuning I would strongly consider getting a hold of one of the vendors here and seeing if you can run a Osiris uprev ecu flash. If your car can support it it will be a great benefit. Usually dynos are done on the top gear to increase the load on the engine thus providing the best possible street load scenario. When done in the lower gears the engine is not as loaded thus sometimes giving a skewed tune and/or netting high sometimes even lower numbers.


Tires (et's) I am unaware of.

If you're going to change the tire sizes I would really look into 1010tires.com they have a really nice tire size calculator that gives you an idea to what your overall diameter will change to. Its best to keep the overall diameter close to stock as possible in order not to throw the vdc into chaos or affect the ride as much either.


When lowering the vehicle it'll throw the geometry off as well. You will need a camber kit to bring it to spec or if you decide not to get one you'll need to take the car to a chassis place and have them modify the chassis which I personally do not recommend. As for the rear I am not 100% sure but there is no kit thatll be able to bring it to spec if youre too low unless you get the bigger cam bolt/alignment bolt along with a small modification to the chassis. I have this modification done and no issues at all.

Welcome to driver!

 

+1 the ONLY thing you should be looking at for tuning is Uprev. If you don't have a certified tuner locally it can be done remotely with datalogs over email

edit: I just saw that you have an 03, wideband support didn't come until 04, so you would have to check the actual air/fuel ratio on the dyno, but as long as you could do a few test runs on the dyno the tune could still be done remotely.

PM me if you have any specific questions about it