Supercharged G 35
SUPERCHARGEDG35
12-06-2003, 10:32 PM
I HAVE AN 03 G 35 WITH AN ATI PROCHARGER ON IT. TOTALLY AWESOME DYNO AT 350 RWHP THAT MEANS WITH A 15-20% DRIVE TRAIN LOSS 420- 450HP AT THE CRANK. POWER IS INSTANT AND SMOOTH. THE ONLY PROBLEM I HAVE RUN INTO IS THE SHIFT POINTS. THE CAR ACCELERATES SO FAST NOW THAT THE RPMS HIT THE REV LIMITER BEFORE THE CAR CAN SHIFT, CAUSING THE CAR TO CUT POWER MOMENTARILY. I HAVE THE PADDLE SHIFTER FOR A MANUAL SHIFT AND I CAN TIME THE SHIFTS WHEN GETTING ON IT. BUT I AM WONDERING IF THERE IS A COMPUTER PROGRAM TO CHANGE THE SHIFT POINTS IN AUTOMATIC MODE. OR EVEN RAISE THE REV LIMITER 200 RPMS IF TYHAT CAN BE SAFELY DONE. ANY QUESTIONS ABOUT THE SUPERCHARGER ARE WELCOME AND ANY INFO ON MY PROBLEM IS MUCH APPRECIATED. :banghead:
riffster
12-30-2003, 02:28 PM
Raising the rev limiter can be done with an ECU upgrade - but I would be very cautious about this - you could start getting into some dangerous territory with air/fuel mixtures and other issues. There have been some posts on My350Z.com about owners having their Z/G engine blow up when using a ProCharger. I would check the very long and informative thread over there about that nasty occurrence. I am NOT dissing ATI - they make great products, it's just that the G and Z are new platforms and some owners have been pushing the envelope on a product that is new and still somewhat untested.
How much boost are you running? If you are getting 420 or 450 at the crank I would be concerned. I have heard that the VQ (and also the AT that comes standard with the auto coupe) are not comfortable with HP over 400 at the crank. That is, unless you have reinforced your internals (forged pistons, stronger cams, etc.,)
You will definitely wear down the engine faster than a NA setup - but I assume you know that. Will you upgrade (or have you upgraded) your internals? The VQ35DE engine is a different animal as compared to many other engines that have had FI added to them. Don't assume because your Eclipse (for example) had FI added and lasted ten years or whatever, that you can do the exact same with the G and a Procharger. It's not better or worse - just different.
I cannot answer your question about changing the shift points - I would suggest that you post over on either Freshalloy.com or My350Z.com - they both have posters who have enough technical proficiency to answer that question plus advise you on safely implementing FI.
Now I have a question for you - how did you get paddle shifts for the G? The G comes with either a stick-shift manual or an automatic with a 'tiptronic' (not paddle) manumatic. I wasn't aware that you could retrofit a paddle shifter onto it.
- Riff
P.S. Easy on the CAPS key guy! :)
How much boost are you running? If you are getting 420 or 450 at the crank I would be concerned. I have heard that the VQ (and also the AT that comes standard with the auto coupe) are not comfortable with HP over 400 at the crank. That is, unless you have reinforced your internals (forged pistons, stronger cams, etc.,)
You will definitely wear down the engine faster than a NA setup - but I assume you know that. Will you upgrade (or have you upgraded) your internals? The VQ35DE engine is a different animal as compared to many other engines that have had FI added to them. Don't assume because your Eclipse (for example) had FI added and lasted ten years or whatever, that you can do the exact same with the G and a Procharger. It's not better or worse - just different.
I cannot answer your question about changing the shift points - I would suggest that you post over on either Freshalloy.com or My350Z.com - they both have posters who have enough technical proficiency to answer that question plus advise you on safely implementing FI.
Now I have a question for you - how did you get paddle shifts for the G? The G comes with either a stick-shift manual or an automatic with a 'tiptronic' (not paddle) manumatic. I wasn't aware that you could retrofit a paddle shifter onto it.
- Riff
P.S. Easy on the CAPS key guy! :)
bk2kmax
01-04-2004, 12:26 PM
I have heard that the VQ (and also the AT that comes standard with the auto coupe) are not comfortable with HP over 400 at the crank. <quoted by riffster
Well that is true for the AT but the VQ has been proven already numerous times to handle over 500hp on whatever kind of boost you are using.
It is safe and can handle the 500hp but it doesn't hurt to have forged crank and cryotreated components under the hood.
Well that is true for the AT but the VQ has been proven already numerous times to handle over 500hp on whatever kind of boost you are using.
It is safe and can handle the 500hp but it doesn't hurt to have forged crank and cryotreated components under the hood.
riffster
01-04-2004, 12:51 PM
Well that is true for the AT but the VQ has been proven already numerous times to handle over 500hp on whatever kind of boost you are using.
It is safe and can handle the 500hp but it doesn't hurt to have forged crank and cryotreated components under the hood.
The AT is definitely an issue - the AT in the coupe is basically the same as in the Q45 and M45. They have 340hp/333torq engines - anything above that and your AT will die sooner than later.
As to the engine itself, I have done some research on this and it appears that while you're technically correct that the VQ can handle more ponies, there have also been some instances of s/c G35's and 350Z's blowing their engines.
This seems to be a problem specifically with ATI Procharger installs that have not been properly tuned. Such improper installs apparently lead to problems with air/fuel mixtures (lean condition) at higher boosts. The theory (no one knows for sure yet) is that this leads to catastrophic detonation that can literally blow a hole in the VQ itself. :( Btw, I am not ragging on ATI -- anything but -- I am ragging a bit on those drivers who don't do their homework prior to modding their car.
Personally, if I ever decide to s/c my coupe I would first wait to see what is the most stable platform for the VQ as it is applied in the 5AT G coupe (matching ECU mapping, etc.,) That will take a year or so I think. If, after that, I think that a real winner has emerged then I will change not only the auto tranny (auto racing tranny from SPG racing for example) but also do as you say about getting forged pistons, new cams and valves.
All in all, if you want to push your performance, you will pay far more than the money you pay for the s/c and some dyno pulls. If you want to settle for the occasional spurt on the road and just have a lively car - you don't have to do that. But if you want to race your car and want it (the engine and drivetrain) to last for any decent period whatsoever, you'll have to fork over about the same amount in cash (maybe more) for other mods as you did for the s/c in the first place!
- Riff
It is safe and can handle the 500hp but it doesn't hurt to have forged crank and cryotreated components under the hood.
The AT is definitely an issue - the AT in the coupe is basically the same as in the Q45 and M45. They have 340hp/333torq engines - anything above that and your AT will die sooner than later.
As to the engine itself, I have done some research on this and it appears that while you're technically correct that the VQ can handle more ponies, there have also been some instances of s/c G35's and 350Z's blowing their engines.
This seems to be a problem specifically with ATI Procharger installs that have not been properly tuned. Such improper installs apparently lead to problems with air/fuel mixtures (lean condition) at higher boosts. The theory (no one knows for sure yet) is that this leads to catastrophic detonation that can literally blow a hole in the VQ itself. :( Btw, I am not ragging on ATI -- anything but -- I am ragging a bit on those drivers who don't do their homework prior to modding their car.
Personally, if I ever decide to s/c my coupe I would first wait to see what is the most stable platform for the VQ as it is applied in the 5AT G coupe (matching ECU mapping, etc.,) That will take a year or so I think. If, after that, I think that a real winner has emerged then I will change not only the auto tranny (auto racing tranny from SPG racing for example) but also do as you say about getting forged pistons, new cams and valves.
All in all, if you want to push your performance, you will pay far more than the money you pay for the s/c and some dyno pulls. If you want to settle for the occasional spurt on the road and just have a lively car - you don't have to do that. But if you want to race your car and want it (the engine and drivetrain) to last for any decent period whatsoever, you'll have to fork over about the same amount in cash (maybe more) for other mods as you did for the s/c in the first place!
- Riff
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