Jump to content
SAU Community

Recommended Posts

Hi guys,

Just been doing some research on weight reduction for 33's and what is a possible goal for a street driven and track car, being as its a R33 GTS4T it weighs a fair bit more than the GTS and GTST's so automatically weight disadvantage right there.

What I've sourced so far is:

Bonnet: Factory 17kgs my carbon one is 7kgs

Boot + Factory Spoiler: 30kgs not 100% on this, carbon fibre 6-8kgs

Air Con System: 12.3kgs

Sound Deadening: Inside the car you can save around 10-15kgs depending how far you go

Rear Seats: 10.9kgs

Front Guards: Not 100% on their weight but I'm running fibreglass guards roughly 6kgs I think I found

Mirrors: 4kgs total replaced with carbon fibre gt mirrors like Craft Square 1kg total

Factory Seats: These I have various figures supposedly 25kg each you can save 10kgs putting in bucket seats

Suspension: Having coilover suspension can save around 4kgs

Doors: inlcuding windows, regulators, door cards and switches around 60kgs for both, carbon fibre with lexcen glass 20kgs

Windows: As above you can change 1/4 windows, door windows and rear windows, wouldnt recommend front windscreen as wipers can damage it

Boot Trim: 6kgs taking out all the unneccsary carpeting and board

Spare Wheel: 16kgs

Jacks + Tools: 3kgs

Metal Bracing behind rear seats 2.9kg

Battery: Change to a smaller and lighter battery few kgs there

Wheels: roughly 18x10 with 265/35 filled with air are around 20kgs, not sure if any savings compared to standard ones there

Steering wheel had airbag as well, replaced with Momo steering wheel and boss kit

Floor mats: 6kgs

I'm trying to get down to around 1300kgs, from what I've read the awd r33 is around 1475kgs. So far I'm around the 1400kg mark but havent removed air con, havent replaced with carbon boot and doors as yet.

I know for extras I can still do:

Headlight duct 1.5kgs I think

Lexcen glass unsure weight reduction

Bucket Seats

HICAS

Carbon Dash

Centre Console

Interior Plastics/Roof lining

Any other thoughts would be great, havent found to many threads across many skyline forums that go into detail on possibilities have just found parts here and there listed.

half of the weights you have mentioned would be pretty optimistic (such as 30kg for the rear wing), or even 4kg for mirrors and only 1kg for carbon mirrors. does that include the glass in the 1kg? i'm guessing it probably wouldn't (especially since it's for the pair).

as for remaining legal, well many of the things you have mentioned will make the car illegal, such as the carbon bonnet, fibreglass guards. i'm not really up on glass requirements, but i have a feeling that all fixed windows need to remain glass (as they are structural). not sure if you can change the front door windows to lexan either.

also, spec weight on the r33 is between 1350 and 1370kg (this is dry weight i think).

Ive had a carbon bonnet since the car was built pulled over and checked many times, lexcen glass and carbon doors would only be put on for track days. I have a rollcage in there and it is street legal being a half cage and car registered as a two seater. Racing harness is ADR approved as are seat rails. You can run fix back seats as long as cars registered as two seater as its not obstructing passengers getting out in emergency. Wheels are within guards and can full lock. As for stripping aircon, sound deadening and interior parts its not legal requirement to have them.

Ive had a carbon bonnet since the car was built pulled over and checked many times, lexcen glass and carbon doors would only be put on for track days. I have a rollcage in there and it is street legal being a half cage and car registered as a two seater. Racing harness is ADR approved as are seat rails. You can run fix back seats as long as cars registered as two seater as its not obstructing passengers getting out in emergency. Wheels are within guards and can full lock. As for stripping aircon, sound deadening and interior parts its not legal requirement to have them.

that doesn't mean it's legal. just means the cop either didn't know it was carbon or didn't know it was illegal. it most certainly is illegal.

Factory Seats: These I have various figures supposedly 25kg each you can save 10kgs putting in bucket seats

Way, WAY off.

R33 factory seats have a combined weight of around 18-19kg (have weighed them). Aftermarket reclinable seats give around 6-7kg weight saving. Fixed back carbon seats will be around 10kg weight saving. The weight of the sliders and rails is nearly 1/3 of the weight of each seat.

Air Con System: 12.3kgs

A bit more. Compressor and condensor with hard lines, belt, pulleys etc. is around 17kg. If you start removing all the stuff inside the car it will be closer to 20kg.

Going to a braided clutch line and braided brake lines will save you around 1-1.2kg and a little bit less fluid.

Two piece brake rotors on the front (even if going bigger) will save you 1-1.5kg each depending on size increase.

If you take all the heater gear out of the car and reroute all the hoses you will save a bit of weight there.

HICAS lock bar will save you 5kg on a R33. If you can somehow manage to remove the HICAS ECU there is another 1kg maybe.

At the end of the day this thread was asking what else can be reduced for weight on the car whether it be legal or not is irrelevant, if it gets defected for something well clearly its my own fault for choosing to do it. I'll be putting in lexcen glass rear quarter windows either way, but the carbon doors will only be fitted for track days as I dont have intrusion bars on my rollcage as its not road legal having them in the car due to a change in Vic Roads regulations.

If people want to get picky on road legal cars people running both pod filters and fmic will get done for two forms of induction...having coilovers are in most cases illegal but alot of jap cars have them installed anyway, same with cars being EPA'd for exhausts...some things we all risk but I stick to legal in most cases.

I remember reading somewhere that Skyline glass isn't that thick and therefore the windows don't actually weigh that much so going to Lexen is really only for the top track cars chasing every last kilogram.

Yeh I read that somewhere as well phil, only reason I'm doing it is mainly for the piping if I remove my aircon it gets some airflow into the cabin :) But supposedly not much saving, I'm just trying to work out where else weight can be shed from the car apart from the above mentioned items...

Hows your car coming along anyway mate??

Did Shane end up getting those carbon cooling panels made in the end or did he pull the plug on that??

Edited by ShyBoi

Yo probably wont end up driving this car on the road anyways cause after removing all this stuff to make it light it wont be comfortable as a street car.. noisy hot & rattly....

Noise doesnt bother me otherwise I wouldnt remove the sound deadening to start with...and with the suspension setup its not exactly smooth at the moment for street driving anyway but I dont have a locker in it so its still smooth enough :)

titanium exhaust & strut tower braces will help with weight reduction..

CF front bar & guards

remove the dash completely use black lexan to cover the wires for legalities maybe....

remove anything that isnt there for driving or performance pretty much

In terms of body kit I'll be leaving that as fibreglass as its already lighter than factory items and especially front bar would require custom fabrication compared to the doors I can pick up easily in carbon. It would be good if I was going for every single kilogram like in a time attack car and had plenty of cash to throw at it. Just to get the dash and centre console done will be somewhat costly.

Anyone know how much the factory dash is in kilograms, I know most people probably dont weigh it, but Im sure a wrecker may be on these threads and can give a rough answer.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I'm looking for some real world experiences/feed back from anyone who has personally ran a EFR7670 with a 1.05 exhaust housing or a .83 I'm leaning towards the .83 because its a street car used mostly for spirited driving in the canyons roads. I"m not looking for big numbers on paper. I want a responsive powerband that will be very linear to 8000 rpm. I dont mind if power remains somewhat flat but dont want power to drop off on top. The turbo I've purchased is a 1.05, although the mounting flange T3 vs T4 and internal vs external waste gates are different on both housings, I not concern about swapping parts or making fabrication mods to get what I want. Based on some of the research I've done with chat gpt, the 1.05 housing seems to be the way to go with slightly more lag and future proofing for more mods but recommends .83 for best response/street car setup. AI doesn't have the same emotions as real people driving a GTR so I think you guys will be able to give me better feed back 😀   
    • Surely somebody has one in VIC. Have you asked at any shops?  Is this the yearly inspection or did you get a canary?
    • This is where I share pain with you, @Duncan. The move to change so many cooling system pieces to plastic is a killer! Plastic end tanks and a few plastic hose flanges on my car's fail after so little time.  Curious about the need for a bigger rad, is that just for long sessions in the summer or because the car generally needs more cooling?
    • So, that is it! It is a pretty expensive process with the ATF costing 50-100 per 5 litres, and a mechanic will probably charge plenty because they don't want to do it. Still, considering how dirty my fluid was at 120,000klm I think it would be worth doing more like every 80,000 to keep the trans happy, they are very expensive to replace. The job is not that hard if you have the specialist tools so you can save a bit of money and do it yourself!
    • OK, onto filling. So I don't really have any pics, but will describe the process as best I can. The USDM workshop manual also covers it from TM-285 onwards. First, make sure the drain plug (17mm) is snug. Not too tight yet because it is coming off again. Note it does have a copper washer that you could replace or anneal (heat up with a blow torch) to seal nicely. Remove the fill plug, which has an inhex (I think it was 6mm but didn't check). Then, screw in the fill fitting, making sure it has a suitable o-ring (mine came without but I think it is meant to be supplied). It is important that you only screw it in hand tight. I didn't get a good pic of it, but the fill plug leads to a tube about 70mm long inside the transmission. This sets the factory level for fluid in the trans (above the join line for the pan!) and will take about 3l to fill. You then need to connect your fluid pump to the fitting via a hose, and pump in whatever amount of fluid you removed (maybe 3 litres, in my case 7 litres). If you put in more than 3l, it will spill out when you remove the fitting, so do quickly and with a drain pan underneath. Once you have pumped in the required amount of clean ATF, you start the engine and run it for 3 minutes to let the fluid circulate. Don't run it longer and if possible check the fluid temp is under 40oC (Ecutek shows Auto Trans Fluid temp now, or you could use an infrared temp gun on the bottom of the pan). The manual stresses the bit about fluid temperature because it expands when hot an might result in an underfil. So from here, the factory manual says to do the "spill and fill" again, and I did. That is, put an oil pan under the drain plug and undo it with a 17mm spanner, then watch your expensive fluid fall back out again, you should get about 3 litres.  Then, put the drain plug back in, pump 3 litres back in through the fill plug with the fitting and pump, disconnect the fill fitting and replace the fill plug, start the car and run for another 3 minutes (making sure the temp is still under 40oC). The manual then asks for a 3rd "spill and fill" just like above. I also did that and so had put 13l in by now.  This time they want you to keep the engine running and run the transmission through R and D (I hope the wheels are still off the ground!) for a while, and allow the trans temp to get to 40oC, then engine off. Finally, back under the car and undo the fill plug to let the overfill drain out; it will stop running when fluid is at the top of the levelling tube. According to the factory, that is job done! Post that, I reconnected the fill fitting and pumped in an extra 0.5l. AMS says 1.5l overfill is safe, but I started with less to see how it goes, I will add another 1.0 litres later if I'm still not happy with the hot shifts.
×
×
  • Create New...