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Emira weight saving

Eagle7

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The 2GR is a great engine. It's low on torque and that supercharger isn't the best. It's reliable power, but not gonna throw you back into the seat. I'm seriously considering throwing my warranty right out the window for a built trans, upgraded supercharger, tune, and some KW V3s. Just gotta find a way or someone who can crack the ecu to tune for the mods. Figure ~$15k in mods on top of the ~$100k msrp and you'll have an Emira pushing 500HP that'll eat exotics twice it's price tag... and look better while doing it too!

But then again I don't really love the idea of buying a $100k exotic sportscar just to modify it, void the warranty, and kill resale value. If I wanted another tuner car, I should just buy a manual Supra or Z again. o_O
REMEMBER... if you decide to do something like this, it's going to put out more heat, so you're going to have to improve the engine cooling. Pay attention to the engine compartment temperatures including the exhaust and catalytic convertor temps. You'll also probably need to replace the radiator in the front with a more efficient, higher capacity unit and a cooling fan, along with possibly a greater capacity, more efficient water pump. Oil and trans temps can become an issue too.

What you're really looking for is power to weight ratio. For $15k you could remove a fair amount of weight by replacing the 12-way power seats with carbon fiber seats, replace the deck lids with carbon fiber, get lighter wheels, titanium exhaust, etc. As Colin Chapman said: "Adding power makes you faster in the straights. Removing weight makes you faster everywhere." Weight reduction will give you the performance improvement without the heat penalty of adding power or the expense of having to deal with that.

If you really want to get into it, go through the car and replace all the metal bolts, washers, nuts and fasteners with high-strength aluminum ones, or titanium where necessary. Go through the car and see what all you'll need. Get the replacements and weigh all of them together. Then start replacing the factory hardware. After replacing all the factory hardware, take all of those and weigh them together like you did with the replacements. You'd be surprised at how much weight all that hardware adds up to. There are things you can do to improve performance without gutting the car or creating new problems, if you find you want more performance once you get your car.
 
REMEMBER... if you decide to do something like this, it's going to put out more heat, so you're going to have to improve the engine cooling. Pay attention to the engine compartment temperatures including the exhaust and catalytic convertor temps. You'll also probably need to replace the radiator in the front with a more efficient, higher capacity unit and a cooling fan, along with possibly a greater capacity, more efficient water pump. Oil and trans temps can become an issue too.

What you're really looking for is power to weight ratio. For $15k you could remove a fair amount of weight by replacing the 12-way power seats with carbon fiber seats, replace the deck lids with carbon fiber, get lighter wheels, titanium exhaust, etc. As Colin Chapman said: "Adding power makes you faster in the straights. Removing weight makes you faster everywhere." Weight reduction will give you the performance improvement without the heat penalty of adding power or the expense of having to deal with that.

If you really want to get into it, go through the car and replace all the metal bolts, washers, nuts and fasteners with high-strength aluminum ones, or titanium where necessary. Go through the car and see what all you'll need. Get the replacements and weigh all of them together. Then start replacing the factory hardware. After replacing all the factory hardware, take all of those and weigh them together like you did with the replacements. You'd be surprised at how much weight all that hardware adds up to. There are things you can do to improve performance without gutting the car or creating new problems, if you find you want more performance once you get your car.
Hi Eagle7
Quick question how much weight would you estimate that changing out the hardware would save. Your comments are brilliant, keep the modifications simple, but incredibly effective.
Love your ingenuity!!!
 
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Hi Eagle7
Quick question how much weight would you estimate that changing out the hardware would save. Your comments are brilliant, keep the modifications simple, but incredibly effective.
Love your ingenuity!!!
If you've ever had a coffee can full of miscellaneous steel bolts, nuts, screws, washers, etc., then you know how heavy even that small amount of hardware can be. I'll have to take a good look at the Emira when I get mine to see how much hardware is on it, but just as an average I'd say you could probably save anywhere from 25-60 lbs depending on how many bolts, washers, nuts, screws and that sort of thing is in the car. I know they use a lot of glue in their chassis. If it's a part that's not in a high stress area, high strength aluminum will work. If it is in a high stress area, or one that gets hot, then titanium hardware can be used. Titanium obviously is going to be more expensive than aluminum, but overall it's not that expensive. This kind of plan really isn't as expensive as it is time consuming. It takes a lot of time to do. You'll need a good torque wrench, a short and long extension for the wrench, and need to know the factory torque requirements for each bolt you replace. Screws are usually just fasteners so there's no torque issue for those.

Just as an example, back when I was going through a weight reduction plan on my 2010 Camaro, I replaced the steel factory lug nuts with high strength aluminum. I took pictures of both on the weight scale.

Factory steel lugs:
Factory lugs.png


Aluminum lugs:
Aluminum lugs.png


As you can see, the factory lugs weighed 3 lbs 2.2 oz, and the aluminum lugs weighed not even a pound for the whole set; only 12.8 oz. A pound is 16 ozs. That's just a set of lug nuts, but it gives you an idea how much weight can be saved if you've gone through and replaced all or most of the heavy steel hardware with lightweight high strength aluminum or titanium.

If you do this, replace only one piece at a time; one bolt/washer, or one screw, and replace it. Don't remove a group or a lot of them to save time. You don't want anything to move from its position, especially something heavy. The only exception would be lug nuts. You'll need to know the strength rating of each bolt/nut you replace, so you can get the equivalent (or better) rated replacement. Don't go cheap; get proper rated high strength components, and they'll last forever. You can probably find all you need online now, but you can also find this kind of hardware at a place that sells aircraft hardware.
 
If you've ever had a coffee can full of miscellaneous steel bolts, nuts, screws, washers, etc., then you know how heavy even that small amount of hardware can be. I'll have to take a good look at the Emira when I get mine to see how much hardware is on it, but just as an average I'd say you could probably save anywhere from 25-60 lbs depending on how many bolts, washers, nuts, screws and that sort of thing is in the car. I know they use a lot of glue in their chassis. If it's a part that's not in a high stress area, high strength aluminum will work. If it is in a high stress area, or one that gets hot, then titanium hardware can be used. Titanium obviously is going to be more expensive than aluminum, but overall it's not that expensive. This kind of plan really isn't as expensive as it is time consuming. It takes a lot of time to do. You'll need a good torque wrench, a short and long extension for the wrench, and need to know the factory torque requirements for each bolt you replace. Screws are usually just fasteners so there's no torque issue for those.

Just as an example, back when I was going through a weight reduction plan on my 2010 Camaro, I replaced the steel factory lug nuts with high strength aluminum. I took pictures of both on the weight scale.

Factory steel lugs:
View attachment 8208

Aluminum lugs:
View attachment 8209

As you can see, the factory lugs weighed 3 lbs 2.2 oz, and the aluminum lugs weighed not even a pound for the whole set; only 12.8 oz. A pound is 16 ozs. That's just a set of lug nuts, but it gives you an idea how much weight can be saved if you've gone through and replaced all or most of the heavy steel hardware with lightweight high strength aluminum or titanium.

If you do this, replace only one piece at a time; one bolt/washer, or one screw, and replace it. Don't remove a group or a lot of them to save time. You don't want anything to move from its position, especially something heavy. The only exception would be lug nuts. You'll need to know the strength rating of each bolt/nut you replace, so you can get the equivalent (or better) rated replacement. Don't go cheap; get proper rated high strength components, and they'll last forever. You can probably find all you need online now, but you can also find this kind of hardware at a place that sells aircraft hardware.

I'd probably just start with a lightweight set of fully forged 18" or 19" wheels. That will probably save ~5-15lbs per corner (considering the smaller/lighter tires too) AND it's unsprung weight and a the smaller diameter will decrease rotational mass. Next step would be lightweight carbon buckets (something ultra light like Tilletts) and then carbon body panels and titanium exhaust. Those would save the most weight.

You've got a problem once you start swapping bolts for titanium. 😂 Isn't the old saying around the track that for every 100lbs of weight shed saves one tenth of a second from your ¼ mile drag speed?

But I agree.. Weight savings is as important as adding power. There was actually a really cool thread I used to follow in my Subaru days called something like "Anorexic STI" where he weighed and documented every single weight savings mod he did to his car. I'll see if I can find it.
 
I'd probably just start with a lightweight set of fully forged 18" or 19" wheels. That will probably save ~5-15lbs per corner (considering the smaller/lighter tires too) AND it's unsprung weight and a the smaller diameter will decrease rotational mass. Next step would be lightweight carbon buckets (something ultra light like Tilletts) and then carbon body panels and titanium exhaust. Those would save the most weight.

You've got a problem once you start swapping bolts for titanium. 😂 Isn't the old saying around the track that for every 100lbs of weight shed saves one tenth of a second from your ¼ mile drag speed?

But I agree.. Weight savings is as important as adding power. There was actually a really cool thread I used to follow in my Subaru days called something like "Anorexic STI" where he weighed and documented every single weight savings mod he did to his car. I'll see if I can find it.
You would hope that the Forged wheels are already light. But then with all the wheel horror stories who knows what we are getting 🤣 Shame they didn't partner with BBS or similar.
I think junking the seats and exhaust system is as much as you could really expect to do in any meaningful way until aftermarket starts producing carbon body parts. But then the body is plastic anyway soooo? 🤷
 
You would hope that the Forged wheels are already light. But then with all the wheel horror stories who knows what we are getting 🤣 Shame they didn't partner with BBS or similar.
I think junking the seats and exhaust system is as much as you could really expect to do in any meaningful way until aftermarket starts producing carbon body parts. But then the body is plastic anyway soooo? 🤷

Not to forget the LiFePO4 weight saving measure, Evora's battery was about 17kg. So there is quite something to get, and iirc coilovers from Öhlins will be the next 12kg of weight loss. Only these two measures will be worth 25-26kg. But they of course come at a price...
 
You would hope that the Forged wheels are already light. But then with all the wheel horror stories who knows what we are getting 🤣 Shame they didn't partner with BBS or similar.
I think junking the seats and exhaust system is as much as you could really expect to do in any meaningful way until aftermarket starts producing carbon body parts. But then the body is plastic anyway soooo? 🤷

IIRC someone was told the forged wheels are like 25-27lbs or something that's only 2-3 lbs lighter than the cast oem 20"s... Which was another disappointment since I expected forged 20"s to be closer to 21-23lbs.
 
IIRC someone was told the forged wheels are like 25-27lbs or something that's only 2-3 lbs lighter than the cast oem 20"s... Which was another disappointment since I expected forged 20"s to be closer to 21-23lbs.
Hmm another good reason to get the BASE and buy something a little more bespoke
 
If you've ever had a coffee can full of miscellaneous steel bolts, nuts, screws, washers, etc., then you know how heavy even that small amount of hardware can be. I'll have to take a good look at the Emira when I get mine to see how much hardware is on it, but just as an average I'd say you could probably save anywhere from 25-60 lbs depending on how many bolts, washers, nuts, screws and that sort of thing is in the car. I know they use a lot of glue in their chassis. If it's a part that's not in a high stress area, high strength aluminum will work. If it is in a high stress area, or one that gets hot, then titanium hardware can be used. Titanium obviously is going to be more expensive than aluminum, but overall it's not that expensive. This kind of plan really isn't as expensive as it is time consuming. It takes a lot of time to do. You'll need a good torque wrench, a short and long extension for the wrench, and need to know the factory torque requirements for each bolt you replace. Screws are usually just fasteners so there's no torque issue for those.

Just as an example, back when I was going through a weight reduction plan on my 2010 Camaro, I replaced the steel factory lug nuts with high strength aluminum. I took pictures of both on the weight scale.

Factory steel lugs:
View attachment 8208

Aluminum lugs:
View attachment 8209

As you can see, the factory lugs weighed 3 lbs 2.2 oz, and the aluminum lugs weighed not even a pound for the whole set; only 12.8 oz. A pound is 16 ozs. That's just a set of lug nuts, but it gives you an idea how much weight can be saved if you've gone through and replaced all or most of the heavy steel hardware with lightweight high strength aluminum or titanium.

If you do this, replace only one piece at a time; one bolt/washer, or one screw, and replace it. Don't remove a group or a lot of them to save time. You don't want anything to move from its position, especially something heavy. The only exception would be lug nuts. You'll need to know the strength rating of each bolt/nut you replace, so you can get the equivalent (or better) rated replacement. Don't go cheap; get proper rated high strength components, and they'll last forever. You can probably find all you need online now, but you can also find this kind of hardware at a place that sells aircraft hardware.
Second thing I am doing after protective film is added to my car!
I would really like to what you replace and with what parts. It would be great to drop 100lbs
 
With the way things are lately, I have a feeling base spec options are going to cost a lot more than most expect. FEs might actually end up being a pretty great deal.
Yes, this might be true.

And one further thing to keep in mind is that Lotus does not have the budget to do real crazy things like Porsche with it's GT4RS or the new GT 3 RS. So we will not see some crazy bits like carbon intakes and 4 Liter conversion stuff. This simply won't happen with the Emira and future GT derivatives.

There is already a receipt for the GT products, one part I already have mentioned above. Öhlins coilovers and some lightweight battery. Racing seats, some carbon stuff interior and a carbon hood instead of the heavy "glass-version" at the rear. And a mild software-upgrade to 430bhp. That's what we could be seeing in the future then.

These are all bolt-ons you can easily apply to your FE Emira, too. So no reason to wait for that, because it may or may not come. We don't know by now.
 
Yes, this might be true.

And one further thing to keep in mind is that Lotus does not have the budget to do real crazy things like Porsche with it's GT4RS or the new GT 3 RS. So we will not see some crazy bits like carbon intakes and 4 Liter conversion stuff. This simply won't happen with the Emira and future GT derivatives.

There is already a receipt for the GT products, one part I already have mentioned above. Öhlins coilovers and some lightweight battery. Racing seats, some carbon stuff interior and a carbon hood instead of the heavy "glass-version" at the rear. And a mild software-upgrade to 430bhp. That's what we could be seeing in the future then.

These are all bolt-ons you can easily apply to your FE Emira, too. So no reason to wait for that, because it may or may not come. We don't know by now.
Yes, this is my final thoughts as well... I would try to reduce weight by ordering base spec with less weighty options. Get the sport suspension, lightest seat and tune the engine to the 430BHP it should always have had. I will be happy at that point. Perhaps option base wheels and order some magnesium 20'' for some better unsprung weight. I don't think waiting for the Final edition is going to work... WAYYY too far away if it ever happens. Only thing I would have loved is the Evija carbon seats... I think they look fantastic.
 
Yes, this might be true.

And one further thing to keep in mind is that Lotus does not have the budget to do real crazy things like Porsche with it's GT4RS or the new GT 3 RS. So we will not see some crazy bits like carbon intakes and 4 Liter conversion stuff. This simply won't happen with the Emira and future GT derivatives.

There is already a receipt for the GT products, one part I already have mentioned above. Öhlins coilovers and some lightweight battery. Racing seats, some carbon stuff interior and a carbon hood instead of the heavy "glass-version" at the rear. And a mild software-upgrade to 430bhp. That's what we could be seeing in the future then.

These are all bolt-ons you can easily apply to your FE Emira, too. So no reason to wait for that, because it may or may not come. We don't know by now.

I hope you're right! I wonder how the Emira would look with a carbon louvered hatch.
 
Tillett will be producing a lightweight race seat for the Emira and @Steve Tillett has an Emira on order

I was looking at the tilletts and one of their seats is quite close to the Evija!
If he does does a more padded version of his normal offering, he could be onto a winner
 
I was looking at the tilletts and one of their seats is quite close to the Evija!
If he does does a more padded version of his normal offering, he could be onto a winner

This! I've raced karts with carbon Tilletts a few months ago and I'm still sore! Ok, that's a bit of an exaggeration, but I definitely want padded seats in my $100k car. Tillett makes some awesome stuff and can't wait to see what's available for the Emira. It'll be great to get the 12-ways out and weight compared!
 
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