Supercharger vs VR30 swap for my 370z Nismo
 

Hello community, sorry for the long post LOL. I know there have been many threads about turbo vs supercharger but this thread isn't in regards to that. I'm looking for more power out of the Z34 chassis. Now my question is in regards to keeping the weight distribution of the chassis balanced. The VR30 would be the obvious choice here as it is only 18lbs more than the VQ37 but it looses some of what makes the VQ37 great with it's high redline, iconic exhaust note and reliability. A supercharger kit weighs around 85lbs according to some sources but I believe in a thread a member stated a net gain of about 30lbs. How could I drop the weight up front (more specifically from the internals) to offset the weight of a supercharger? I have already considered battery relo, dry carbon parts, wheels, tires, etc. My goal is too keep the overall weight of the car low, improve its front/rear weight distribution and make over 450hp. I just wanted to know if my goals would be realistically possible with a supercharger otherwise I'll probably be doing a VR30 swap :stirthepot:.

I'd say an engine swap to save less than 50lbs is a smart way to go so go do that. You'll definitely notice the difference. Just take pictures along the way!

Not sure how you would get it to pass smog inspection in Cali with a VR30.

Definitely won’t pass smog in Ca. But then again if putting this much effort for weight distribution I’m hoping it’s not a street car anyway as the little bit of difference between vq37 and vr30 you’ll never notice the difference on a street driven car. And if going full blown race car then just add oil coolers and such to the back of the car to regain the balance.

You can do an engine swap and pass smog CARB if the engine you're installing is out of a newer car than the chassis that it's going in and retains the original smog equipment (including cats) that that are required for that engine. Of course it would have to go through CARB testing and that could be extensive and expensive. There's a company that does LS3 swaps in Miata's that meet CARB standards.

That is correct, which is why I figured the VR30 swap would also work in my favor. It costs less that $50 to get the car smog legal by taking it to a referee station and getting it approved with a BAR sticker. So it is definitely doable here in Cali. In regards to the other members the car would be a street car AND be seeing track days and maybe drag strips. I know some might argue the power increase might not be useful on the street but a nice torque jump is something I think definitely would be :driving: The rotrex supercharger that was just released seems like a very nice choice if it wasn't for the weight. Anyone know how much the net weight gain is with the kit and how much weight I can drop from the engine itself (forged internals)??:icon14:

If your talking about a built VQ, then throwing a Rotrex on there is going to blow the power to weight ratio out of the water over a VR swap.

Dry sump, lower the center of gravity and push the engine back far as possible. If you’re really serious about weight distribution.

How serious are you on the track? Because it sounds like you're looking to spend a lot of time/money trying to fix a problem that isn't really a problem.

I definitely would not use weight distribution as the deciding factor on whether to go SC or VR30. There are far more relevant factors.

If I were inclined to do a VR30 swap, I'd wait for the new Z to come out, get wrecked and buy a donor 6MT car and swap the entire engine, 6MT, ECU, IPDM, EPS, keyless system over.
That way you'd have a fully sorted car that complies with the latest emission requirements.
Currently the only donor for a VR30 is the 7AT-only Infiniti Q cars. I haven't seen a fully-sorted VR30 swap yet. I know there are some good running swaps, but they don't have EPS (no provisions for hydraulic PS on VR30 AFAIK) so they don't have power steering, and I know that the ECU isn't intended for a 6MT car.

Doing a VR swap sounds nice but...........Your car will be down longer than you think. Getting everything sorted out. Going with the SC, you could pound it out in a week. You won't notice the extra weight, believe me. Some trackrats have been bolting down lead weight in the rear to balance out the car. There is no way to remove enough off the front to balance it to 50/50 unless you move the engine back 8".

I did consider this option at one point but found that the associated costs and downsides were not in line with the goal of my car build.

You are right in saying that the issue I'm having isn't really a "problem". I don't think I would ever take my car to be a serious track machine as I would be getting rid of a lot of creature comforts as I still want it to be streetable, but the way I see it is if it can be improved in some way then that is a plus in my book.

If I were to go with the VR30 swap route, I would be doing something like this. Mainly because the new revised VR30 has changes that make it more suitable for better performance and all the original issues with wiring would be sorted out.

Yes the downtime is something to think about, but it wouldn't be a deciding factor for me as I have other means of transportation. Although I do want to say that I am NOT looking to achieve a 50/50 ratio as it would require a lot more money and more weight added and would just be unrealistic. I would be looking for something closer to 52/48 distribution but I would have to increase the overall weight of the car and depending on which route I take I would be adding either something like 60lbs or something like 180lbs to offset the weight at the front.

I have been lurking in the other thread on here on your rotrex kit and up until that point I have not seriously considered a supercharger kit but after seeing dyno sheets and improvements I was very happy with the way the torque curved looked. I know that from the beginning of your development you wanted the kit to be CARB legal, how far along are you on this process?

Honestly, pretty far. I wouldnt hold your breath on that. I am already getting lots of attention on the Q50 turbo kits so that will keep us busy and Ive been eyeballing a new platform to get into.

Im not saying I wont do it, I am just unsure of when I will.