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No, but it would reduce weight.
You will be surprised how much more notable replacing the oem muffler by a lightweight one is and even more natable stiil only unbolting the front crash bar.
The 30 kilos of fuel sit bang on the center of giration.
It is a nice test to do a swisty norm route with the tank full, with the light on, then with the frump loaded with 30 kilos vs empty.

Still, yes, 30 kilos remaisn 30 kilos. I have the nearest petrol station at 1 km. only and it is also the drop off point for every package I receive so I fill up 15 liters when the light has been on for 15 - 60 kms.

 

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You will be surprised how much more notable replacing the oem muffler by a lightweight one is and even more natable stiil only unbolting the front crash bar.
The 30 kilos of fuel sit bang on the center of giration.
It is a nice test to do a swisty norm route with the tank full, with the light on, then with the frump loaded with 30 kilos vs empty.

Still, yes, 30 kilos remaisn 30 kilos. I have the nearest petrol station at 1 km. only and it is also the drop off point for every package I receive so I fill up 15 liters when the light has been on for 15 - 60 kms.

How does removing front crash bar affect handling as far as flex from strut towers through to front chassis rail ends go? I run a cage that passes through firewall and is essentially welded to strut towers but don’t run a strut brace. Did you notice any softening or flex in the front with it off? Maybe even better turn in?
 

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How does removing front crash bar affect handling as far as flex from strut towers through to front chassis rail ends go?
Two totally different things:
The crash bar does nothing to stiffness and removing decreases the rotational inertia = quicker change of direction for a given input or more traction at the front wheels for a given spped of chance.
Adding a connection between the two shock towers is adding a connection between the top mounts of the king pins of the steering = more exact directional movement this control.
I did both ;)
among other things ofcourse: I found that the TRD bars to the lower rear suspension arms did a lót to the handling. It made turning natably more taut and the more undualting the surface the more notable. Véry confidence inspiring because of increased feedback in the bum.
Now that latter only makes sense with more supportive seats like fitting buckets.
The betters upport also makes you can use your hands for steering only; have no steering inputs from body movement nor (consciously or sunconsciously) holding on to the steering wheel.
Properly fitting, supporting, (bucket) seats thus do a lót for the handling of the car.
As they are a good weight saving too I´d say the are quite high on the list of effective mods.
 

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Discussion Starter · #51 ·
As they are a good weight saving too
Not really much if you want a reclining seat. I did some digging and an adjustable seat even if it's carbon is at best only going to get you 8 lbs per seat. I have been looking and the MR2 seat is a somewhat light OEM seat. I would have gone with hard carbon buckets but I drive up in the mountains for hours at a time and that would probably destroy my back worse than my Elise did.
 

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Not really much if you want a reclining seat.
Hence I wrote buckets ;)

I chose to leave a fair bit of kilos on the table because I opted for twó sets of OEM rails/basis. One from a LHD and the other from a RHD.
This way both buckets are still sliding and adjustable in inclination. The latter makes for fine adjustment whereas the former is also very practical for use of the space behind them. It after all still is my daily for use in charming company.
 

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I have the car pretty well sorted as I like it. Most would call it twitchy.

Ok, I jump at putting a supercharger on giving a bit more grunt and 30 horses but that is not on the books here because of homologation.

Lighter hood, rear lid, plastic windscreen are on the backburner for when something would appear affordably within the EU.

For the moment though it is repairing galore; total engine rebuild and parking damage repair.
 

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Two totally different things:
The crash bar does nothing to stiffness and removing decreases the rotational inertia = quicker change of direction for a given input or more traction at the front wheels for a given spped of chance.
Adding a connection between the two shock towers is adding a connection between the top mounts of the king pins of the steering = more exact directional movement this control.
I did both ;)
among other things ofcourse: I found that the TRD bars to the lower rear suspension arms did a lót to the handling. It made turning natably more taut and the more undualting the surface the more notable. Véry confidence inspiring because of increased feedback in the bum.
Now that latter only makes sense with more supportive seats like fitting buckets.
The betters upport also makes you can use your hands for steering only; have no steering inputs from body movement nor (consciously or sunconsciously) holding on to the steering wheel.
Properly fitting, supporting, (bucket) seats thus do a lót for the handling of the car.
As they are a good weight saving too I´d say the are quite high on the list of effective mods.
My engineering judgement is that the rear crash bar adds significantly to the overall chassis torsional stiffness, just like the rungs in a ladder add torsional stiffness to a ladder.

Dave
 

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My engineering judgement is that the rear crash bar adds significantly to the overall chassis torsional stiffness, just like the rungs in a ladder add torsional stiffness to a ladder.

Dave
I am still on the fence whether the rear one has any benificial effect in chassis stiffness, hence I left it in place. Just shaved the outer sides off and took minimal material from the inside flat (see the stiffness of the fitting to the rails).
As you could have seen, I wrote about the front one. Have taken thát one off.
Placed photos of the frónt off, the rear in situ ;)

This observed, the crash bars are nót an integral part of the special steel chassis.
You can find that illustrated in the chassis drawings.
This stands to reason as they are meant to deform relatively easily and in the process absorb energy. Thus neither are they all that sturdily fixed to the chassis rails. The nuts only hold one flat of the bar and that, agaín, is designed to be relatively nót rigid.
In mý structural engineering knowledge the crash bars are like using thin screws to fit a pvc tube to the outer ends of your ladder :geek:
 

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As mentioned time and again by humorists in EVERY thread about weight saving, I dó watch my own weight as well.
Apart from simply for healtht living, for weight ánd for the fit in thus feedback through the buckets.

This weekend was spoiled rotten for my birthday. Two gfs so twíce spoiled rotten and also in at léast subconscious spoiling competition. Yes they gave extra excersize as well but the food part won without a doubt :ROFLMAO:

No harm done though as the car will not be ready in a week and by then I will have undone the ´damage´ (y)

p.s. down on the Friday weight already :p As there is quìte some leeway in the green BMI zone, best keep that momentum going a bit.
The lighweight flywheel arrived too.
 

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I am still on the fence whether the rear one has any benificial effect in chassis stiffness, hence I left it in place. Just shaved the outer sides off and took minimal material from the inside flat (see the stiffness of the fitting to the rails).
As you could have seen, I wrote about the front one. Have taken thát one off.
Placed photos of the frónt off, the rear in situ ;)

This observed, the crash bars are nót an integral part of the special steel chassis.
You can find that illustrated in the chassis drawings.
This stands to reason as they are meant to deform relatively easily and in the process absorb energy. Thus neither are they all that sturdily fixed to the chassis rails. The nuts only hold one flat of the bar and that, agaín, is designed to be relatively nót rigid.
In mý structural engineering knowledge the crash bars are like using thin screws to fit a pvc tube to the outer ends of your ladder :geek:
 

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I agree that the front crash bar has a lower effect on chassis torsional stiffness than the rear, but I still judge that it is significant. Try this: jack up one corner of the car (with the beam removed) and see if the 3 studs on each side still line up with the holes in the crash bar.

Dave
 

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I agree that the front crash bar has a lower effect on chassis torsional stiffness than the rear, but I still judge that it is significant. Try this: jack up one corner of the car (with the beam removed) and see if the 3 studs on each side still line up with the holes in the crash bar.

Dave
One: Be aware that you test is flawed. You are taking out any flex of the bar/fitting when mounted out of the equasion.

Two: I did it properly and actually méasured chassis flex as a matter of course for other things and my argument was underlined; the front crash bar and fittings are too flexible to make a difference.
At the rear the overhang of the chassis rails is too short to see any difference.

On a side note, the front strut brace made hardly if any any difference either. Boris´ front lower member brace díd. Note mine is a PFL.
 

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One: Be aware that you test is flawed. You are taking out any flex of the bar/fitting when mounted out of the equasion.

Two: I did it properly and actually méasured chassis flex as a matter of course for other things and my argument was underlined; the front crash bar and fittings are too flexible to make a difference.
At the rear the overhang of the chassis rails is too short to see any difference.

On a side note, the front strut brace made hardly if any any difference either. Boris´ front lower member brace díd. Note mine is a PFL.
Actually, a more sensitive way to do this test is to jack up one corner with the front bar installed and see it it moves when you loosen one side's fasteners.

Dave
 
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