As everyone who builds a car knows, we’re always craving a bit more speed and performance. There are, of course, a few ways to go about this but instead of bolting a huge turbo onto your engine or throwing loads of cash into a massive NA tune there is another way. Weight loss! Power to weight ratio is essential (in my opinion). It lets my little Civic (174bhp/tonne) keep up with a Celica GT4 (166bhp/tonne) around track. That’s a 1.6 NA (estimated around 165bhp) vs a 2.0 Turbo (240bhp according to the interwebz). If you’re not afraid to lose a few comforts it can be relatively cheap to do! So here’s how:
Base car is a 1992 Honda Civic ESi
Exterior
Bonnet: A very simple swap to do. 4 bolts to undo and you’re away! Depending on the option you choose, it can be quite an expensive buy but there are bargains out there. I managed to pick up a (slightly damaged) Seibon Carbon Fibre bonnet for £80! Be aware, with lightweight bonnets it is advisable to give the bonnet that extra bit of security and safety.
OEM EG Bonnet: 15.2 KG
Carbon Fibre Bonnet: 9.2 KG
Fibreglass Bonnet:
A quick Google shows the cheapest Carbon bonnet at roughly £360 which would mean it costs you around £72 per kilo saved.
Headlights: Again, another simple swap to do! You’ll need to lift the bonnet, remove the front bumper and indicators and then you’re free to swap the headlights over. Standard UK Headlights have glass lenses whereas JDM spec headlights come with a plastic lens. Glass is heavier than plastic so swap the over! (If you can find them) Be aware though, JDM headlights use a H4H bulb which can be pretty difficult to find. You could also use some cheap eBay crystal lights or angel eyes too but I have no weights for those and I very much doubt they will have a lens on that disperses light properly for MOT time.
Pair of OEM Glass Headlight Lenses: 1.992 KG
Pair of JDM Plastic Headlight Lenses: 0.602 KG
I bought a pair for around £40 means it’s a costing you around £29 per kilo saved.
Sunroof: Now this swap is a little more difficult but it is a very beneficial swap to do! It will save a lot in weight but more importantly it lowers the centre of gravity! To remove the sunroof you will have to first remove the head liner. You will have to remove the A, B and C pillar trims to get to the plastic screws that secure the lining. You also need to remove the sun visors, interior light and handles that are around the roof. One last challenge to get the head liner out is to carefully prise out the plugs which hold the centre of the liner up, and I mean be careful as you can dent the roof if you’re too hard with them! Once you have the head liner out you can get to the sunroof. It will have 4 water channels that need unclipping, a couple of plugs and then you can remove the 6 bolts that hold up the sunroof. The next step, to block up the hole, can be a bit tricky. Depending on what method you go for, changes how you will attack this next step. You can just get a sheet of aluminium cut to overlap the hole slightly and wack a bead of tiger seal round the edge to seal it, while riveting the plate to the roof or... you could buy a bung. I bought a carbon fibre bung made to fit the recess. To fit it I had to run a bead of tiger seal round the edge of the recess (or bung) and then awkwardly hold it in place while it dried. I didn’t develop a very good method, using lots of masking tape and trying to do it all myself so I’d recommend making some sort of stand and getting a friend to help! I’d also recommend running another bead of tiger seal around the edge (inside and out) once it is dried in place so that it is completely sealed!
OEM Metal Sunroof & Mechanism: 12.9 KG
Carbon Fibre Sunroof Bung: 0.6 KG
Fibreglass Sunroof Bung: 1.5 KG
Now I paid £180 for my Carbon Fibre bung and possibly £10 for a tub of Tiger Seal, which means it cost me £15 for each kilo saved. The Fibreglass bung will be a fair amount cheaper so will give a better ratio and if you went down the aluminium bung method you’d probably get an even better cost/saving ratio.
Tailgate: Not as simple as the bonnet switch but still relatively easy. To remove the tailgate itself it’s simple 2 bolts on each hinge and a bolt each side for the wire support. You will also have to remove the wiring loom which can be fed out of the tailgate and the tailgate catch wire. The tailgate will then be free to remove. Depending on the style of tailgate you’ve got to replace it with you’ll need to swap over various things. Most will come with recesses for the lights so it will simply be unbolting the lights and bolting them to the new tailgate. The loom should also fit straight in. The side catches and upper catch will also need to be switched over and hopefully these should bolt straight on. The boot lock may be an optional thing, mine doesn’t have it (and you don’t really need it with the interior boot release), but if you do want it you may be able to drill out the hole and retro fit it but it’s not something I’ve tried.
OEM JDM Tailgate: Around 8.5 KG
Carbon Fibre Tailgate: Around 5 KG
Fibreglass Tailgate:
I can’t seem to find many prices for these brand new, one price I came across is £440 for a Carbon tailgate which would mean it costs you £126 per kilo saved!
Foglights: Whether you’ve got genuine Stanley’s or dodgy eBay tat remove the foglights will save you a bit of weight and it’s completely free! You could even make a bit of money off your weight saving. Removing them should go along the lines of removing the front bumper, unplugging the loom from the foglights and unscrewing the units from the bumper. You’d then have to trace back the wiring into the interior cabin (if you want to go that far with it!) If you have OEM Stanley lights they’ll be a ground near the light units which will need undoing and then a plug to separate the interior and engine bay side of the looms to make it a bit easier. Now after removing the foglights you’ll have two nice holes in your bumper so you could add an intake duct over one side to cover it up and serve as a cold air feed.
OEM Foglights & Wiring: 1.8 KG
Carbon Fibre J’s Racing Style Duct: 0.15 KG
Rear Spoiler: So much choice! The OEM spoiler doesn’t actually weigh that much. Of course the brake light versions weigh a tad more but not too much. One thing the OEM spoilers aren’t good for is aerodynamics. You can save weight and add downforce but it’s difficult to achieve. I’ve weighed a few spoilers and as you’ll see, the savings are minimal. If you don’t know how to replace your spoiler, lift up the rear hatch glass and you’ll see 4 domed nuts. Remove those and the spoiler will be loose. You’ll then have to unscrew the rear washer jet and disconnect a plug and there you have it, the old spoiler is off.
OEM One Piece Metal Spoiler: 2.297 KG
OEM Two Piece Spoiler w/ Small Brake Light: 2.3 KG
Spoon Carbon Fibre Spoiler (Genuine): 1.961 KG
So you can see for a £200 plus spoiler it only saves you around 340 grams! That’s a cost of something like £588 for a kilo of weight lost (to put it in perspective as everything else!) What I’ve done now though is make my own spoiler. I used a sheet of 0.9mm aluminium which costs barely anything and made a spoiler similar to a Spoon stlye at fraction of the cost! And slightly less weight too.
Front Wings: This isn’t something I’ve personally changed as of yet but I do have some information for it. It will be minimal weight saving again but with Carbon Fibre wings you’ll be trés baller. These are the weights I’ve been given.
OEM Metal Front Wings: 4.136 KG
Fibreglass Front Wings: 2.6 KG
Fibreglass wings cost around £150 I believe so this modification will be hitting your pocket for around £100 for every kilo saved. Carbon Fibre wings may offer a slightly better saving but will cost twice as much! Bare in mind though... Fibreglass or Carbon Fibre wings will offer you the benefit of not rusting!
Mudflaps: Nice and easy to remove and if you’re going all “because race car” they’re not needed at all. If I remember rightly both front and rear mudflaps are held on by 4 screws each. The front’s are pretty simple, needing only to put the wheels on a loc to get enough space to get the the screws. The rears on the other hand are a little more tricky. The inner screw may require removal of the wheel to access, unless you can squeeze a tiny screwdriver in the gap or use a small Phillips bit.
Set of 4 OEM Mudflaps: 1.28 KG
Of course this costs you nothing to do so sell them on, enjoy that extra burger at the track and spend the money earned on some fresh oil etc.
Front Lips/ Splitters/ Spoilers: Whatever you want to call them, they’re the same as the rear spoiler. They don’t offer much of a weight saving. If you’re looking at drag racing and not bothered about the aerodynamics then you can do away with the OEM lip and save a kilo. For on track though, you’ll want something to benefit your cars aerodynamics so you’ll more than likely end up adding a bit of weight here.
OEM Front Lip w/ Fitting Kit: 0.68 KG
Mirrors: So simple to swap, but won’t offer too much of a weight saving. The mirrors are only held on by 8mm nuts but you may need to remove the door cards to gain proper access to them. There are of course two options to start with. Manual and electric mirrors. I’ve found out that both units pretty much weigh the same! But with the electric units you will have the extra weight of the wiring and the controls (minimal I know but every little counts right?). There are a few aftermarket options out there but the only one I went for were the lightest (and coolest) of them all, APR Carbon Fibre Mirrors. They saved a little but did cost quite a bit!
OEM Electric Mirrors (Pair of Units + Wiring & Controls): 2.8 KG
OEM Manual Mirrors (Pair of Units): 2.3 KG
APR Carbon Fibre Mirrors (Pair of Units): 1 KG
So for replacing your electric mirrors with a set of manual OEM mirrors may cost you £20 but you’ll only save 500 grams or so. Hitting your pocket with (in theory) £40 for every kilo saved. APR Mirrors however save 1.8 KG, but costing around £200 they will cost £111 for every kilo saved.
Engine Bay
Washer Bottle: I guess not many will think of swapping this out to save weight. Remember, it’s not only the bottle that you’re removing, but also the water it contains! (And water weighs 1 KG for every litre). So, whip off your front bumper and get that old big washer bottle off! You’ll only need to undo 3 bolts and then remove two plugs and two washer lines. If you’re so racecar and don’t want washers then leave it at that, but if you need at least front washers for a daily then I suggest getting a small 1.5 litre bottle from the likes of Demon Tweeks. They come with brackets you can bolt anywhere, and then you’ll just have to reconnect the front washer pipe and wire up the appropriate wires to the original loom. (The OEM plug obviously won’t fit the new bottle).
OEM Washer Bottle (And 5.5 Litres of Water): 6.2 KG
Small Washer Bottle (And 1.5 Litres of Water): 1.75 KG
So for the small sum of around £15 you’re actually saving around 4.5 KGs! Working out at just over £3 for every kilo saved! Possibly one of the most cost effective modifications you can do.
Battery: You might not think it but the battery is quite a weighty bit of kit! It also sits relatively high up in the car being at the top of the engine bay. You would benefit from reducing the weight and placing it in a place closer to the ground. It’s very very simple to swap a battery, but it will get complicated if you decide to relocate it while you’re at it. I haven’t done this yet so I can’t walk you through the ins and outs of it but when I do, I’ll post it up.
OEM Sized Battery: Around 12 KG
Small Race Battery: Around 7 KG
Air Conditioning System: The chances are, if you’re EG comes with air conditioning, it probably doesn’t work too well. Mine didn’t work at all so I removed it to save weight and free up a few horses. The first thing you should know when removing the AC is, it is illegal to vent the gasses from the system into the atmosphere so be warned! When you’re system if free of gas it is pretty simple to remove (with a bit of common sense). You may need to remove the bumper to allow a bit easier access, but you will need to remove the battery to gain easy access to the firewall join and you will need access to the vents behind the glovebox. First remove the AC belt and then remove the pump off the engine. You’ll need to trace back all lines back through the engine bay to the firewall. There will also be the AC radiator and condenser to remove. Once everything is removed from the engine bay you will be left with a big heavy cooler under the dashboard. You will have to remove the glovebox and make sure everything is free on the engine bay side! It’s the centre section you want to remove from the vents! They’ll be 3 or 4 screws holding it in place, one or two plugs to...unplug and then it should be free. If it’s anything like mine was it will be full of leaves. Of course you’ll have to replace it with a non AC duct which is simply a light empty join between the fan and the heater matrix. For the heater controls themself, all you need to do is prise off the push switch from the AC section and put a blanking plate over it (which most EGs will have anyway)
Air Conditioning System: 14.97 KG
It won’t cost you a thing to remove but it may cost you a whole 50p or something silly to buy that centre section of the vents. So in theory it will cost a few pence for every kilo saved!
Power Steering System: Now this is a funny one. You’ve got to weigh up a few options. Yes it will save you weight, and yes it will (in theory) free up a few horses but there are a few things to consider. Your steering will become heavier. In my opinion, you will only notice it when parking or at very low speeds but I also think you get a better feedback of the road without PAS. MOT time is another thing to consider. I’ve had problems in the past with MOTs because of my PAS removal. It’s all down to the tester, if they want to pick holes in your car they will fail it for having the PAS system missing (and a PAS rack installed) so be warned!
To remove the system it can be quite difficult, especially with the engine in! With a bit of common sense it is relatively straight forward though. You will need to start by removing the PAS belt to free up the pump. Next you’ll have to find something to drain the system into. If you spill the PAS fluid it is a very messy job to clear up so be careful! Try and find a low point so that gravity will drain the system for you. Once you are confident most of the system is drained it’s time to start unbolting the system. Work your way from the pump backwards, unbolting all brackets and disconnecting any pipes associated with the system. You’ll find you soon come to the firewall and get a bit stuck if you have the engine in. This is the difficult part and you may need a bit of help. You’ll have to climb under the car and try and prise off the clips holding down the PAS pipes from behind the subframe to free them. It might be worth undoing the pipes from the steering rack at this point to make it a bit easier. There’s no easy way to do it, you’ll have to find a way and wiggle out the pipes. With the engine out there’s a lot more room and it’s easier to access so you’ll have no trouble. Once the pipes are free of the subframe and the entire system is out you’ll be left with two holes in your steering rack. What I did was cut off the two pipes that connect to the rack with about 2 inches of length. I then got a bit of spare pipe off the system and looped it between the two pipes to create a circuit before putting them back in the rack. There is another way though. You can start the same way by cutting the pipes but then getting some new rubber pipe from each join running to a T section piece. The spare exit on the T section will run to a clutch reservoir bottle with a bit of PAS fluid in it. That way it will let you keep a bit of fluid in the system to make sure it stays lubricated. Make sense?
Power Steering System: 7.71 KG
This should be another free modification but if you go down the route of using the clutch reservoir you will need to spend a pound or two buying those pieces!
Crank Pulley: Once you’ve removed PAS and AC you’ve always got the option of swapping out the crank pulley for a lighter model. There is a lot of fuss about whether it’s good for your engine etc but it’s something you’ll have to read about and make your own mind up. I’ve used two different makes on two different engines without trouble. For this example I’m taking a standard B16A2 crank pulley and putting on a B16B N1 Crank Pulley. It’s a pretty simple job to do. You’ll have to get the car in the air and remove the passenger wheel to gain access to the crank pulley bolt. Slacken off the alternator belt and remove it. The easiest way to remove the crank pulley is to get the holder tool for the pulley! It’s a hex socket shape which slots into the pulley and allows you to hold it while you undo the nut. It saves so much swearing and frustration trying to undo the bolt other ways. Stick that holder in, wedge it in place and crack off the crank bolt. Undo it so you can remove the pulley. Do not lose the woodruff key! Fitting is the reverse of removal. Make sure you torque up the crank pulley. Lightweight pulleys are usually slightly smaller than standard pulleys so you will need a slightly smaller alternator belt!
OEM B16A2 Crank Pulley: 4.5 KG
OEM B16B N1 Crank Pulley: 0.8 KG
The N1 pulleys cost around £80 to buy and will save you 3.7 KGs. So that’s around £22 for every kilo saved. Don’t forget, losing weight from this part will make your engine more responsive and free up a few more horses!
Exhaust Manifold: Standard manifolds are restrictive and heavy! Swapping out to an aftermarket manifold will help the flow of exhaust gases but also save you a slight bit of weight. They can be a bit fiddly to swap over. You’ll have to remove the O2 sensor from your standard manifold (penetration spray will make this a whole lot easier! – generally they’re rusted tight). Be careful with the sensor, they’re fragile. Then you’ll have to remove the nuts from the head studs, bolts from the join with the catalytic converter and the bolts from the other brackets holding it up. Fitting is reversal of removal but you might benefit from replacing the exhaust manifold gasket and the donut gaskets so your system is fully sealed!
OEM B16A2 Manifold: 8.16 KG (Unconfirmed)
SRS 4-2-1 Manifold (2” collector): 7.58 KG
5Zigen 4-2-1 Manifold (2.5” collector): Haven’t managed to weigh this yet.
So it’s not much a saving comparing the OEM to SRS but I’d imagine better brands are a little lighter still. I can’t find an exact price for an SRS manifold but let’s say £150. This means, in terms of weight saving, it costs you £259 for every kilo saved.
Catalytic Converter: Now obviously for MOT purposes most cars that came with a Cat need to keep it on, but who really sticks to that all year round? Fitting a decat will make your system less restrictive but also save you a kilo or two. They’re also dead simple to swap. Once the car is in the air you’ll see two bolts on the manifold side and 3 on the centre section side. It might be worth spraying them with some penetration spray before attempting to crack them off, especially if they haven’t been removed since the car left the factory. Really it’s as simple as undoing all bolts and dropping the cat out. You shouldn’t need to change the donut gasket on the manifold but the centre section gasket may need replacing depending on how degraded it is. Either way, make sure you smear some exhaust sealant around the joins before fitting the decat!
Short (JDM Length) Catalytic Converter (2”): 2.18 KG
Adjustable Decat (2.25”): 1.18 KG
Fixed Length Decat (2.5”): Weight Unknown
Now it really depends where you go to how much you pay for a decat. I was desperate for one when I got my system so ended up buying an adjustable one from Hond-R for around £90, but the larger fixed one I have on my car now cost around £30 to make by Solid Fabrications. If I take the adjustable decat that cost me £90 for a kilo saved, but that was a very expensive decat!
Part
Weight (KG)
Wheels
14" Honda Civic Steel Wheels (Set of 4) 36.28 KG
15" Honda Civic Jordan Alloys (Set of 4) 35.6 KG
15" Work E-Wing Rsa Alloys (Set of 4) 23.6 KG
15" Honda Civic EK9 Alloys (Set of 4) 29.324 KG (7.331 KG Each)
5 Stud Spacesaver with tyre (Single) 11.312KG
Brand New Toyo T1-R 195/50/15 (Single) 7.747 KG
Engine
D16Z6
B16A2
D16Z6 Gearbox
B16A2 Gearbox Y21
OEM B16A2 Crank Pulley 4.5 KG
OEM B16B N1 Crank Pulley 0.8 KG
Air Conditioning System 14.97 KG
Power Steering System 7.71 KG (1.92 Bracket / 2.52 Pump + Bottle) (Rest probably made up from fluid/bolts and pipes)
OEM B16A2 Cast Iron Manifold 8.16 KG (Unconfirmed)
SRS 4-2-1 Manifold 7.58 KG
5Zigen 4-2-1 Manifold
OEM EG5 Cat-Back Exhaust System
HKS Super Drager Center Section (2") 6.54 KG
HKS Super Drager Backbox (2.25") 7.22 KG
Spoon N1 Backbox (2.5") 3.336 KG
Spoon N1 Bung 0.273 KG
Solid Fabrication Custom Center Section (2.5")
JDM Length Catalytic Converter (2.25") 2.18 KG
Slip Fit Decat (2.25") 1.18 KG
OEM B16A2 Flywheel 8.62 KG
Fidanza Lightweight Flywheel 3.63 KG
OEM EG5 Airbox & Resonator 3.5 KG
OEM ITR Airbox & Cold Air Feed 0.3 KG (Just the C.A.F weight atm)
Suspension
OEM Shocks & Springs
Meister R Zeta S Coilovers 13.732 KG (7.292 (Front Pair) 6.44 (Rear Pair))
OEM Front Upper Control Arms (Pair)
BuddyClub Front Caber Kit (Pair) 2.62 KG
OEM Rear Lower Control Arms (Pair) 3.72 KG
Function 7 Lower Control Arms (Pair) 1.82 KG
Spoon Front Upper Strurt Brace 1.035 KG
Spoon Rear Upper Strut Brace 1.48 KG
Beaks Rear Lower Tie Bar
H Brace 1.204 KG
OEM Rear Upper Control Arms (Pair) 1.12 KG
D2 Rear Camber Kit (Pair) 1.537 KG
Brakes
13/16" Master Cylinder & Servo
1" ITR 98' Spec Master Cylinder & Servo
242mm EG5 4 Stud Front Hubs (Pair)
282mm ITR 5 Stud Front Hubs (Pair)
242mm EG5 4 Stud Rear Hubs (Pair)
262mm ITR 5 Stud Rear Hubs (Pair)
OEM Rubber Hoses (4 of)
Goodridge Braided Hoses (4 of)
Exterior
OEM Glass Headlight Lenses (Pair) 1.992 KG
OEM Plastic Headlight Lenses (Pair) 0.602 KG
OEM Metal Sunroof 12.9 KG
Fiberworx Carbon Fibre Bung 0.6 KG
Fiberworx Sunroof Bung - 1.5 KG approx
OEM JDM Metal Tailgate 8.5 KG (Unconfirmed)
Seibon Carbon Fibre Tailgate 5 KG
OEM Metal Bonnet 15.2 KG
Seibon Carbon Fibre Bonnet 9.2 KG
OEM Fog Lights (Inc. Wiring) 1.8 KG
Teishi Carbon Fibre Air Duct 0.15 KG
OEM One Piece Metal Spoiler 2.297 KG
OEM Two Piece Spoiler with Small Brake Light 2.3 KG
Spoon Carbon Fibre Spoiler 1.961 KG
OEM Washer Bottle 0.712 KG
Volume of water (5.5 litre) 5.5 KG
Demon Tweeks Washer Bottle 0.25 KG
Volume of water (1.5 litre) 1.5 KG
OEM Front Lip with fitting kit 0.68 KG
OEM Mudflaps (Set of 4) 1.28 KG
Cutting grills out front bumper 0.620 KG
OEM Front Wing - 2.068 KG
Fiberworx Fiberglass Front Wing - 1.3 KG
Interior
Carpet & Sill Protectors 4.1 KG
OEM EDM Tape Console 1.1 KG
OEM Gearstick Surround 0.45 KG
OEM JDM Short Armrest 1.3 KG
OEM EG Steering Wheel (Non SRS) - 2.784 KG
OEM/MOMO EG Black Magic Steering Wheel & Boss - 2.033 KG
OEM Electric Mirrors (Pair) 2.2 KG
OEM Manual Mirrors (Pair) 2.3 KG
APR Carbon Mirrors (Pair) 1.017 KG
Drivers Door Wiring 0.56 KG
Passenger Door Wiring 0.16 KG
OEM Parcel Shelf 3.56 KG
OEM Rear Seats 13.94 KG
OEM EG5 Rear Plastics (Rear Quarters & Tailgate Trim) 8 KG
Headliner 2.2 KG
OEM Door Cards (Manual Windows) (Pair) 5.518 KG
OEM Door Cards (Electric Windows) (Pair) 6.32 KG
OEM Electric Window Mechanism (Pair) 7 KG (Unconfirmed)
OEM Manual Window Mechanism (Pair) 5 KG (Unconfirmed)
OEM Front Door Glass (Pair) 2.6 KG
Heater Matrix - Center 0.36 KG
Heater Matrix - Blower Box 2.40 KG
Heater Matrix - Heater Core 4.90 KG
Heater Matrix - Controls 0.64 KG
OEM Tape Player 1.90 KG
Dashboard 9.2 KG
Glovebox - 0.84 KG
Rear Wiper (Wiper arm, motor, casing, wiring NOT BACKING PLATE) 1.3 KG
Tar Sound Deadening & Seam Sealer (Didn't have any under the rear seats) 3.5 KG
Firewall Sound Deadening 4 KG
Rear Seatbelts 2.61 KG
Luke 6 Point Harness 3.18 KG
OEM EG5 Front Seats (with rails) 15 KG
OEM EK9 Recaro Front Seats (Single) 13.75 KG
DC2 Rails (Single) 4.75 KG
BuddyClub P1 Limited Edition Seat (GT Large size) (Single) 7.167 KG
Japshop Rails (Single side) 3.851 KG
OEM Black Floor Mats (Set of 4) 3.6 KG
OEM Scissor Jack 1.668 KG
OEM Tool Kit 1.398 KG
Additional help with the list would be nice, but I'll need a pic to show proof of the weight before I add it
=]
