The 370Z Weight Reduction Thread

[Dwnshift]

Here ya go.....

[Pauly]

sub

[wstar]

oh those cf headlight covers are nice, just saw the update. got a source/price? I could see myself swapping these out for a track day

[Shamu]

Originally Posted by wstar

You mean some kind of snap-in replacements that are empty shells for racing during the day?

I haven't looked closely ...is it easy to pull and replace headlights? If this is case I'd love ability to put cf cover on for hillclimb. More info?

[wstar]

I would assume you have to remove the bumper first, but I do that and more prepping for a track weekend anyways, usually. There's always some maintenance or parts stuff going on up in that area Another upside is not having to worry about either taping over the real headlights or letting them get dinged.

[7419sundat]

Ppe headers = 12lbs each

[Shamu]

Weighed the Nismo front bumper cover = 11 lbs.

Also weighed AC compressor unit = 15 lbs

[cavemancan]

I see tons of good information but very little emphasis is being placed on the front end of the car where it counts. I wanted to comment on a few things I have read so far:

- Nissan designed the car intentionally to have a 53/47 weight distribution: I know they mention this and claim the car then gets a 50/50 weight distribution while exiting a corner but what many don't realize is this causes a push situation on corner entry which is further amplified by lack of negative camber. I personally think this was a marketing ploy...they probably found it would be to expensive to shed more weight from the front.

- Everyone seems dead set on sheding weight from the car...As am I but so far the primary focus has been mostly towards the back of the car. With good reason of course cause it easy. We need to research what could be removed from the front.

Ideas:
- The front strut bar was a very good idea. In fact if there was an aftermarket strut bar made I am sure we could realize a good reduction in weight.
- Rotors are not specifically for the front but thus far seem to be the best option for weight savings so far due to the location and type of weight reduction.
- Engine plastics...Has anyone weighed these? Any Adverse affects to cooling or airflow?
- Long Tube Headers seem to be a good solution.
- Windsheild is a good idea but prob to extreme for most to undertake.
- AC is another good idea but prob to extreme for most

What else? What about removing as much weight from the top of the car and relocating it to the bottom rear of the car? This will lower your center of gravity and balance out the weight distribution. Another option is to work with you have and increase tire width and negative camber in the front.

[wstar]

We're mostly aware of the focus on front weight. It's hard to find good savings up front through. I can tell you from my experience (I'm sure many others could too), your questions above:

- Most aftermarket strut bars are larger and stiffer than the original. Not sure what the weight diff is, but I'd assume heavier.
- Lightweight front 2pc rotors are awesome, if you're at a point where the money on them is justifiable (keep in mind it's not a one-time thing, you will have to replace rings).
- Yes, you can pull all the plastic crap out of the engine bay, it works fine. If you go the extra step of pulling the top edge stuff by the windshield you get some engine bay heat reduction to boot, but I wouldn't run like that on the street.
- Yes, Long-tube headers are a well-documented weight savings.
- Windshield (e.g. Lexan) is a bad idea on a car that ever drives on the street.
- AC - don't really know how much it all weighs, but I'm sure it's a good chunk on a car that doesn't need AC anymore.

Other front weight thoughts:

- Battery - one of the larger front static weight drops you can find. Downsize and/or relocate.
- Radio - The head unit isn't all that heavy, but combined with all the front wiring it's decent. Still, the audio hardware you'd pull from the center/rear of the car is considerably heavier, so in the net gutting all audio gear from the car doesn't shift weight in the good direction.
- Windshield washer reservoir (and associated tubing / jets). It's way out in the passenger front corner. You can get most of the savings by just keeping it dry instead of hauling a gallon of water out there. But the plastics are worth something too, and they also free up a good spot for running various cooler hoses or small cooler units. I've been running without one forever on the street, it's not bad. Just use gas station window washer squeegees more often.
- Windshield wipers - if you kill the wipers, motors, wiring, etc, it's a decent chunk and fairly high up. I wouldn't do it on a street car you might drive in the rain of course, Rain-X doesn't perfectly handle all conditions where you need to see out the front
- On the oil cooling front - probably one of the better options for decent cooling combined with weight savings in the right places is a Laminova oil:water cooling unit (inside the engine bay) and an upgraded radiator. Initial reports on this kind of setup from Travisjb indicate that the heat xfer works great, but you need additional airflow to the radiator to keep the water cool (airflow baffles in the bumper, etc). It's gotta beat running long heavy braided lines to a 34-row hanging way out on the front edge of the car.

As for top-to-bottom:

- Kill the XM Radio antenna from the top of the car if you have a touring model, plug the square hole with something (I just used a rubber plug and some silicone sealant).
- The headliner, auto-dim/homelink mirror, upper airbags, etc from the inside of the roof add up to a fair chunk up high. No point going down this route unless it's pretty much exclusive track machine though, in which case you'd obviously pull all the airbag and seatbelt hardware anyway.
- Z1's undertrays are heavier than stock, which is going to add front weight. But they're still worth it IMHO, and since the weight is so low they probably shift CG down by a hair. Ditto for extended/baffled oil pans - you want them for other benefits, but dropped CG is a decent compromise for the added front weight.

If you dig around the engine bay, there are a lot of smaller optimizations too. None of them are worth much individually, but over time every little bit helps. A recent example I found: in the driver's side front corner of the engine bay, you'll see a plastic fuse box attached to the wall with a couple of small bolts. It's marked on top like it contains several fuses and relays, but actually it's some generic part to several Nissan cars apparently. Open it up and there's only a single fuse or relay (I forget which) inside there, the rest is all empty. So I unbolted that box and got it and its mounting hardware out of the car, and just ziptied the one fuse/relay/whatever to the side of the nearby wiring harness it comes from.

[SPOHN]

I just wish I could get one person that has deleted there AC show me a pic of it. I want to see there replacement bracket. I've emailed several guys here that have claimed they removed but no response with makes me call BS. Guess I'll have my shop do it.

[cavemancan]

Originally Posted by wstar

- Yes, you can pull all the plastic crap out of the engine bay, it works fine. If you go the extra step of pulling the top edge stuff by the windshield you get some engine bay heat reduction to boot, but I wouldn't run like that on the street.

- Z1's undertrays are heavier than stock, which is going to add front weight. But they're still worth it IMHO, and since the weight is so low they probably shift CG down by a hair. Ditto for extended/baffled oil pans - you want them for other benefits, but dropped CG is a decent compromise for the added front weight.

Regarding the top edge plastics. Was the cooling measured? How do you know there is a cooling effect here? The reason I ask this is because by removing those plastics you are effectively turning that area into an air intake (think cowl induction).

What benefit do then undertrays offer? I've seen them but I did not read or notice any benefit that would cause me to buy one.

Thanks for the reply...I'm playing devils advocate for a reason I would hate to modify or purchase an aftermarket part only to negatively effect my plans for the car.

[ChrisSlicks]

Originally Posted by cavemancan

What benefit do then undertrays offer? I've seen them but I did not read or notice any benefit that would cause me to buy one.

None in my opinion.

I bought one thinking it would improve airflow and cooling but all it did was get beat to s**t by the sway bar.

Right now I run no undertray at all, which probably hurts straight line speed a little due to additional air getting underneath. If I get a properly vented hood (with the vents in the right places) then I will reinstall an undertray, probably the plastic one, although the Zspeed is stiffer.

[wstar]

No measurements on the plastic removal, just common sense. Anything that gets more air exchanged out of the bay has to drop temps in there, same idea as hood vents. FWIW, I removed the engine cover, but left the upper stuff all in place. I like the little bit of shield it gives to the two corner compartments from heat (brake master cylinder in one, and I have my PCV catch can mounted in what used to be the battery area - if it stays a little cooler than the surrounding stuff it condenses better).

Re: undertray, it's not a huge benefit really, but it's worth it to me all the same. I like that it adds a bit of rigidity to the front of the car (not driving/suspension rigidity - plastic bumper/underside rigidity against pressure deformation at speed), as it solidly affixes the bottom edge of the front bumper and the edges of the corner underside plastics to the hard frame. The older Version 1 of it that I have, combined with my no-longer-available AMPerf baffled oil pan sticking out a bit more than stock, also adds up to more cooling (as the aluminum oil pan is pressed into contact with the giant aluminum undertray). Probably some fringe benefits in scrape/impact situations over the stock plastic too, but I don't scrape much anyways.

[cavemancan]

Originally Posted by wstar

No measurements on the plastic removal, just common sense. Anything that gets more air exchanged out of the bay has to drop temps in there, same idea as hood vents. FWIW, I removed the engine cover, but left the upper stuff all in place. I like the little bit of shield it gives to the two corner compartments from heat (brake master cylinder in one, and I have my PCV catch can mounted in what used to be the battery area - if it stays a little cooler than the surrounding stuff it condenses better).

See this is why I am inclined to disagree. By removing the plastics next to the window you are not exchanging air out of the engine bay. You are effectively pumping air into the engine bay. Since air is already being fed into the engine bay from the front bumper I am not sure how the air is flowing here but it has to go somewhere. You might even be causing lift at high speeds due to the excessive air preasure in the engine bay which might be forced under/behind the engine then under the car.

Can you post a pic of your engine bay plastics? Just curious how you have it setup.

Thanks!

Chris

[cavemancan]

Originally Posted by ChrisSlicks

None in my opinion.

I bought one thinking it would improve airflow and cooling but all it did was get beat to s**t by the sway bar.

Right now I run no undertray at all, which probably hurts straight line speed a little due to additional air getting underneath. If I get a properly vented hood (with the vents in the right places) then I will reinstall an undertray, probably the plastic one, although the Zspeed is stiffer.

Yeah I saw no significant improvement over stock based on the pics I saw.