Mind Candy--Possible 545i Weight Savings
10-25-2005, 04:16 PM
#61
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Originally Posted by 545smg' date='Oct 25 2005, 06:59 PM
[quote name='donv' date='Oct 25 2005, 03:06 PM']Bump idy do dah.
Bump idy ay.
My oh my what a wonderful day.
I bumped because I added some new info to my original post. Is my off-the-wallness showing? I'm not nuts. I just have many very silly moments. And, anyway, I want this thread to achieve the stature of the mud-flap thread. ~{;^). Bump idy do dah. ....
Bump idy ay.
My oh my what a wonderful day.
I bumped because I added some new info to my original post. Is my off-the-wallness showing? I'm not nuts. I just have many very silly moments. And, anyway, I want this thread to achieve the stature of the mud-flap thread. ~{;^). Bump idy do dah. ....
[snapback]188580[/snapback]
what is the mobility kit????
[snapback]188596[/snapback]
[/quote]That's an excellent question. I am so glad you asked. Check out Trunk Funk for info on the mobility kit and the now well-know BMW mobility-kit mod. ~0{;^)
10-25-2005, 04:19 PM
#62
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Originally Posted by 545smg' date='Oct 25 2005, 07:00 PM
[quote name='donv' date='Oct 25 2005, 03:06 PM']Bump idy do dah.
Bump idy ay.
My oh my what a wonderful day.
I bumped because I added some new info to my original post. Is my off-the-wallness showing? I'm not nuts. I just have many very silly moments. And, anyway, I want this thread to achieve the stature of the mud-flap thread. ~{;^). Bump idy do dah. ....
Bump idy ay.
My oh my what a wonderful day.
I bumped because I added some new info to my original post. Is my off-the-wallness showing? I'm not nuts. I just have many very silly moments. And, anyway, I want this thread to achieve the stature of the mud-flap thread. ~{;^). Bump idy do dah. ....
[snapback]188580[/snapback]
why not add flywheel while you're at it?
[snapback]188597[/snapback]
[/quote]Good point, maybe I should. But, I was looking at the weight-savings primarily from the point of view of a Steptronic equipped 545i--like mine. And, you can't do at least the Dinan light-weight flywheel on a Step.
11-08-2005, 06:34 PM
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why did it take me so long to read this post 
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me..
....forget it, I've tried and just refuse to give up the "cold suds" 
Cheers,
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me..
....forget it, I've tried and just refuse to give up the "cold suds" Cheers,
11-09-2005, 10:17 AM
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Originally Posted by Bokke' post='195509' date='Nov 8 2005, 10:34 PM
why did it take me so long to read this post
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me.. ....forget it, I've tried and just refuse to give up the "cold suds"
Cheers,
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me..
....forget it, I've tried and just refuse to give up the "cold suds" Cheers,
11-24-2005, 05:13 PM
#65
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why did it take me so long to read this post
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me.. ....forget it, I've tried and just refuse to give up the "cold suds"
Cheers,
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me..
....forget it, I've tried and just refuse to give up the "cold suds" Cheers,
[/quote]For anyone interested, here is where I think I ended up--all in lbs.
Weight Savings from Wheels: 2[(34 ? 22.5) + (32 ? 22.5)] = 42 (BMW Style 101 19" wheels versus Sport package 18" wheels)
Weight Savings from Tires: 2[(32 - 25) + (29 ? 25)] = 22 Michelin Pilot Sport 2's versus Dunlop Run Flats
Wheels/Tires--Total Weight Savings: 64
Equivalent Sprung Weight Savings: 2(22) + 1.5(42) = 107
Weight Savings from Removing Spare: 35 (Addition of Mobility Kit Offsets Removal of Jack)
Weight Savings from B&B Exhaust: 30
Total Equivalant Sprung Weight Savings: 107 + 35 + 30 = 172
Flywheel HP Equivalent = 172 / 10 = 17.2 (i.e., 10 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [(3,814 - 172)] / 325] - (3,814 / 325) = 11.206 - 11.735 = -.529
or, approximately, equivalently:
Change in lbs. / HP ratio = [3,814 / (325 + 17.2)] - (3,814 / 325) = 11.146 - 11.735 = -.589
To equate the two,
Flywheel HP Equivalent = 172 / 11.2 = 15.35 (i.e., 11.2 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [3,814 / (325 + 15.35)] - (3,814 / 325) = 11.206 - 11.735 = -.529
Take your choice.
12-23-2005, 07:08 PM
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Originally Posted by Bokke' post='195509' date='Nov 8 2005, 10:34 PM
why did it take me so long to read this post
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me.. ....forget it, I've tried and just refuse to give up the "cold suds"
Cheers,
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me..
....forget it, I've tried and just refuse to give up the "cold suds" Cheers,
Weight Savings from Wheels: 2[(34 ? 22.5) + (32 ? 22.5)] = 42 (BMW Style 101 19" wheels versus Sport package 18" wheels)
Weight Savings from Tires: 2[(32 - 25) + (29 ? 25)] = 22 Michelin Pilot Sport 2's versus Dunlop Run Flats
Wheels/Tires--Total Weight Savings: 64
Equivalent Sprung Weight Savings: 2(22) + 1.5(42) = 107
Weight Savings from Removing Spare: 35 (Addition of Mobility Kit Offsets Removal of Jack)
Weight Savings from B&B Exhaust: 30
Total Equivalant Sprung Weight Savings: 107 + 35 + 30 = 172
Flywheel HP Equivalent = 172 / 10 = 17.2 (i.e., 10 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [(3,814 - 172)] / 325] - (3,814 / 325) = 11.206 - 11.735 = -.529
or, approximately, equivalently:
Change in lbs. / HP ratio = [3,814 / (325 + 17.2)] - (3,814 / 325) = 11.146 - 11.735 = -.589
To equate the two,
Flywheel HP Equivalent = 172 / 11.2 = 15.35 (i.e., 11.2 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [3,814 / (325 + 15.35)] - (3,814 / 325) = 11.206 - 11.735 = -.529
Take your choice.
[/quote]
For any interested, I have assessed the validity of the above calculations given use of my GT2 G-meter in my more recent G-meter thread.
12-26-2005, 05:03 AM
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Originally Posted by derrickj' post='184426' date='Oct 14 2005, 08:40 PM
[quote name='donv' date='Oct 14 2005, 03:24 PM'][quote name='donv' date='Sep 18 2005, 07:18 PM']Hi All (I just noticed after all this time--Esthetic = Aesthetic ~0{:^)):
First, here is a question. How many miles would an average driver get on the 545i?s Dunlop run flats? The answer affects the economics of my/our individual weight-savings thoughts. You?ll have to factor in your particular circumstances. Also, note that I am not working with package pricing below--just with per wheel/tire prices. Forgive me for any mistakes; please let me know if you see any or question anything in the calculations. I?ll adjust or clarify.
1. By buying, for example, Michelin Pilot Sport PS2's, one can save the following (all weights below in lbs.) over the Dunlop run flats.
2(32 - 25) + 2(29 - 24) = 24 lbs. Given that unsprung weight is being saved, the sprung-weight equivalent is about 2(24) = 48 lbs.
2. By buying, for example, BBS RGR's, one can save the following over the stock sports package wheels.
2(34(?) - 21.2) + 2(32(?) - 19.4) = (approx.) 51 lbs. Given again that unsprung weight is being saved, the sprung-weight equivalent is about 1.5(51) = (approx.) 77 lbs.
3. The donut tire and jack weight about 37 lbs., together, while an after-market exhaust is likely to be about 30 lbs. lighter than the stock behemoth.
So, in sprung-weight terms, one can save about 48 + 77 + 37 + 30 = 192 lbs. with ease and without hurting the esthetics any if at all.
4. Given use of the lbs./Flywheel HP ratio, 192 pounds translates into about 192 / 10 = about 19 flywheel HP--or (48 + 77) / 10 = 125 / 10 = about 13 flywheel HP from the wheels/tires alone.
So, the first question is how about the economics of obtaining, for example, the portion of the increase in flywheel ?HP? attributable to the wheels/tires alone? Suppose that one will need to replace his or her run flats before disposing of the 545i. If so, then the cost of the extra tires is pretty much nil and is ignored below for ease. And, given a US$ price of 2($702) + 2($731) = $2,866 for the RGR?s and that one could sell the wheels, plus what's left of the Michelins, when disposing of the 545i for half the cost of the wheels ($1,433), then the cost of the wheels is $1,433.
5. So, the extra 13 "HP" from the wheels/tires alone cost about $1,433 / 13 = about $110.23 per HP--which is somewhat economical given, for example, that a Dinan trottle body, when installed by a Dinan certified shop, will cost, with a 10% discount on the part, about $685--which yields a cost per flywheel HP of about $685 / (8 / .85) = $685 / 9.4 = about $72.78. And, the wheel/tire package also will result in more that just an increase in HP?specifically, it will improve handling and some might say the esthetics. Finally, the run flats and factory wheels would be available for use?say on trips. I am assuming that the throttle body will not be sold when the 545i is disposed of.
6. Similarly, consider the cost, for example, of a B&B exhaust. The cost if installed by a BMW dealer, after a 10% discount on the part, is about $1,063. The related flywheel HP gain is about (10 RWHP / .85) + (30 lb. weight savings / 10) = about 15 HP. The cost per HP is ($1,063 / 2 / 15 = about $35.44 assuming the exhaust can be sold net eventually for half of its cost (about $532).
7. Together, all the costly weight savings, plus actual HP gains from the related items, gives a net cost of ($1,433 + $685 + $532) = $2,650. The cost per HP is $2,650 / (13 + 9.4 +15) = $2,650 / 37.4 = $71?which is similar to the per HP cost of the throttle body, itself.
8. So, the 545i ends up with 325 + 37.4 = about 362.5 flywheel ?HP.? If one throws in the 37 / 10 lb. saving from removing the spare tire, then the 545i?s flywheel HP is about 366?which is not too shabby. Thus, either way, one ends up with performance in the 550i range and is much better off not buying a comparable 550i if he or she already owns a 545i (i.e., consider loss on 545i and probably non-discounted or higher discounted price of 550i, price increase on 550i, etc., etc., and etc.) (ignoring the other new features of the 550i--which mean nothing to me).
The final cost per flywheel HP is $2,650 / (37.4 + 3.7) = $2,650 / about 41 = about $65?but no spare in the car.
Phew. I?m tired; I?ll keep checking my calculations?later. Any thoughts?
First, here is a question. How many miles would an average driver get on the 545i?s Dunlop run flats? The answer affects the economics of my/our individual weight-savings thoughts. You?ll have to factor in your particular circumstances. Also, note that I am not working with package pricing below--just with per wheel/tire prices. Forgive me for any mistakes; please let me know if you see any or question anything in the calculations. I?ll adjust or clarify.
1. By buying, for example, Michelin Pilot Sport PS2's, one can save the following (all weights below in lbs.) over the Dunlop run flats.
2(32 - 25) + 2(29 - 24) = 24 lbs. Given that unsprung weight is being saved, the sprung-weight equivalent is about 2(24) = 48 lbs.
2. By buying, for example, BBS RGR's, one can save the following over the stock sports package wheels.
2(34(?) - 21.2) + 2(32(?) - 19.4) = (approx.) 51 lbs. Given again that unsprung weight is being saved, the sprung-weight equivalent is about 1.5(51) = (approx.) 77 lbs.
3. The donut tire and jack weight about 37 lbs., together, while an after-market exhaust is likely to be about 30 lbs. lighter than the stock behemoth.
So, in sprung-weight terms, one can save about 48 + 77 + 37 + 30 = 192 lbs. with ease and without hurting the esthetics any if at all.
4. Given use of the lbs./Flywheel HP ratio, 192 pounds translates into about 192 / 10 = about 19 flywheel HP--or (48 + 77) / 10 = 125 / 10 = about 13 flywheel HP from the wheels/tires alone.
So, the first question is how about the economics of obtaining, for example, the portion of the increase in flywheel ?HP? attributable to the wheels/tires alone? Suppose that one will need to replace his or her run flats before disposing of the 545i. If so, then the cost of the extra tires is pretty much nil and is ignored below for ease. And, given a US$ price of 2($702) + 2($731) = $2,866 for the RGR?s and that one could sell the wheels, plus what's left of the Michelins, when disposing of the 545i for half the cost of the wheels ($1,433), then the cost of the wheels is $1,433.
5. So, the extra 13 "HP" from the wheels/tires alone cost about $1,433 / 13 = about $110.23 per HP--which is somewhat economical given, for example, that a Dinan trottle body, when installed by a Dinan certified shop, will cost, with a 10% discount on the part, about $685--which yields a cost per flywheel HP of about $685 / (8 / .85) = $685 / 9.4 = about $72.78. And, the wheel/tire package also will result in more that just an increase in HP?specifically, it will improve handling and some might say the esthetics. Finally, the run flats and factory wheels would be available for use?say on trips. I am assuming that the throttle body will not be sold when the 545i is disposed of.
6. Similarly, consider the cost, for example, of a B&B exhaust. The cost if installed by a BMW dealer, after a 10% discount on the part, is about $1,063. The related flywheel HP gain is about (10 RWHP / .85) + (30 lb. weight savings / 10) = about 15 HP. The cost per HP is ($1,063 / 2 / 15 = about $35.44 assuming the exhaust can be sold net eventually for half of its cost (about $532).
7. Together, all the costly weight savings, plus actual HP gains from the related items, gives a net cost of ($1,433 + $685 + $532) = $2,650. The cost per HP is $2,650 / (13 + 9.4 +15) = $2,650 / 37.4 = $71?which is similar to the per HP cost of the throttle body, itself.
8. So, the 545i ends up with 325 + 37.4 = about 362.5 flywheel ?HP.? If one throws in the 37 / 10 lb. saving from removing the spare tire, then the 545i?s flywheel HP is about 366?which is not too shabby. Thus, either way, one ends up with performance in the 550i range and is much better off not buying a comparable 550i if he or she already owns a 545i (i.e., consider loss on 545i and probably non-discounted or higher discounted price of 550i, price increase on 550i, etc., etc., and etc.) (ignoring the other new features of the 550i--which mean nothing to me).
The final cost per flywheel HP is $2,650 / (37.4 + 3.7) = $2,650 / about 41 = about $65?but no spare in the car.
Phew. I?m tired; I?ll keep checking my calculations?later. Any thoughts?
[snapback]172125[/snapback]
I think the result is very good; I am sure that I can feel a fairly distinct difference before and after all the changes. And, I really like the looks of the wheels and tires. Money well spent. I've posted the pic below in the parts, mods, etc., dicussion. But, here it is again. I like it.
[snapback]184299[/snapback]
[/quote]I LOVE your wheels
Do you think your throttle body has made any perceptible difference? I have been thinking about it. One thing that I have done (and actually went with JDN one night) is take it out to an 1/8 mile track and get the actual run time. I would love to know yours.[/quote]
Hi derricki just read your post regarding you and JDN going to the 1/8 mile strip.what were your times? Just curious as i have times from a 1/4 strip(terrible weather day).Have conversed with JDN in tha past and enjoyed his posts
12-26-2005, 07:05 AM
#68
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Originally Posted by donv' date='Oct 14 2005, 03:24 PM
[quote name='donv' date='Sep 18 2005, 07:18 PM']Hi All (I just noticed after all this time--Esthetic = Aesthetic ~0{:^)):
First, here is a question. How many miles would an average driver get on the 545i?s Dunlop run flats? The answer affects the economics of my/our individual weight-savings thoughts. You?ll have to factor in your particular circumstances. Also, note that I am not working with package pricing below--just with per wheel/tire prices. Forgive me for any mistakes; please let me know if you see any or question anything in the calculations. I?ll adjust or clarify.
1. By buying, for example, Michelin Pilot Sport PS2's, one can save the following (all weights below in lbs.) over the Dunlop run flats.
2(32 - 25) + 2(29 - 24) = 24 lbs. Given that unsprung weight is being saved, the sprung-weight equivalent is about 2(24) = 48 lbs.
2. By buying, for example, BBS RGR's, one can save the following over the stock sports package wheels.
2(34(?) - 21.2) + 2(32(?) - 19.4) = (approx.) 51 lbs. Given again that unsprung weight is being saved, the sprung-weight equivalent is about 1.5(51) = (approx.) 77 lbs.
3. The donut tire and jack weight about 37 lbs., together, while an after-market exhaust is likely to be about 30 lbs. lighter than the stock behemoth.
So, in sprung-weight terms, one can save about 48 + 77 + 37 + 30 = 192 lbs. with ease and without hurting the esthetics any if at all.
4. Given use of the lbs./Flywheel HP ratio, 192 pounds translates into about 192 / 10 = about 19 flywheel HP--or (48 + 77) / 10 = 125 / 10 = about 13 flywheel HP from the wheels/tires alone.
So, the first question is how about the economics of obtaining, for example, the portion of the increase in flywheel ?HP? attributable to the wheels/tires alone? Suppose that one will need to replace his or her run flats before disposing of the 545i. If so, then the cost of the extra tires is pretty much nil and is ignored below for ease. And, given a US$ price of 2($702) + 2($731) = $2,866 for the RGR?s and that one could sell the wheels, plus what's left of the Michelins, when disposing of the 545i for half the cost of the wheels ($1,433), then the cost of the wheels is $1,433.
5. So, the extra 13 "HP" from the wheels/tires alone cost about $1,433 / 13 = about $110.23 per HP--which is somewhat economical given, for example, that a Dinan trottle body, when installed by a Dinan certified shop, will cost, with a 10% discount on the part, about $685--which yields a cost per flywheel HP of about $685 / (8 / .85) = $685 / 9.4 = about $72.78. And, the wheel/tire package also will result in more that just an increase in HP?specifically, it will improve handling and some might say the esthetics. Finally, the run flats and factory wheels would be available for use?say on trips. I am assuming that the throttle body will not be sold when the 545i is disposed of.
6. Similarly, consider the cost, for example, of a B&B exhaust. The cost if installed by a BMW dealer, after a 10% discount on the part, is about $1,063. The related flywheel HP gain is about (10 RWHP / .85) + (30 lb. weight savings / 10) = about 15 HP. The cost per HP is ($1,063 / 2 / 15 = about $35.44 assuming the exhaust can be sold net eventually for half of its cost (about $532).
7. Together, all the costly weight savings, plus actual HP gains from the related items, gives a net cost of ($1,433 + $685 + $532) = $2,650. The cost per HP is $2,650 / (13 + 9.4 +15) = $2,650 / 37.4 = $71?which is similar to the per HP cost of the throttle body, itself.
8. So, the 545i ends up with 325 + 37.4 = about 362.5 flywheel ?HP.? If one throws in the 37 / 10 lb. saving from removing the spare tire, then the 545i?s flywheel HP is about 366?which is not too shabby. Thus, either way, one ends up with performance in the 550i range and is much better off not buying a comparable 550i if he or she already owns a 545i (i.e., consider loss on 545i and probably non-discounted or higher discounted price of 550i, price increase on 550i, etc., etc., and etc.) (ignoring the other new features of the 550i--which mean nothing to me).
The final cost per flywheel HP is $2,650 / (37.4 + 3.7) = $2,650 / about 41 = about $65?but no spare in the car.
Phew. I?m tired; I?ll keep checking my calculations?later. Any thoughts?
First, here is a question. How many miles would an average driver get on the 545i?s Dunlop run flats? The answer affects the economics of my/our individual weight-savings thoughts. You?ll have to factor in your particular circumstances. Also, note that I am not working with package pricing below--just with per wheel/tire prices. Forgive me for any mistakes; please let me know if you see any or question anything in the calculations. I?ll adjust or clarify.
1. By buying, for example, Michelin Pilot Sport PS2's, one can save the following (all weights below in lbs.) over the Dunlop run flats.
2(32 - 25) + 2(29 - 24) = 24 lbs. Given that unsprung weight is being saved, the sprung-weight equivalent is about 2(24) = 48 lbs.
2. By buying, for example, BBS RGR's, one can save the following over the stock sports package wheels.
2(34(?) - 21.2) + 2(32(?) - 19.4) = (approx.) 51 lbs. Given again that unsprung weight is being saved, the sprung-weight equivalent is about 1.5(51) = (approx.) 77 lbs.
3. The donut tire and jack weight about 37 lbs., together, while an after-market exhaust is likely to be about 30 lbs. lighter than the stock behemoth.
So, in sprung-weight terms, one can save about 48 + 77 + 37 + 30 = 192 lbs. with ease and without hurting the esthetics any if at all.
4. Given use of the lbs./Flywheel HP ratio, 192 pounds translates into about 192 / 10 = about 19 flywheel HP--or (48 + 77) / 10 = 125 / 10 = about 13 flywheel HP from the wheels/tires alone.
So, the first question is how about the economics of obtaining, for example, the portion of the increase in flywheel ?HP? attributable to the wheels/tires alone? Suppose that one will need to replace his or her run flats before disposing of the 545i. If so, then the cost of the extra tires is pretty much nil and is ignored below for ease. And, given a US$ price of 2($702) + 2($731) = $2,866 for the RGR?s and that one could sell the wheels, plus what's left of the Michelins, when disposing of the 545i for half the cost of the wheels ($1,433), then the cost of the wheels is $1,433.
5. So, the extra 13 "HP" from the wheels/tires alone cost about $1,433 / 13 = about $110.23 per HP--which is somewhat economical given, for example, that a Dinan trottle body, when installed by a Dinan certified shop, will cost, with a 10% discount on the part, about $685--which yields a cost per flywheel HP of about $685 / (8 / .85) = $685 / 9.4 = about $72.78. And, the wheel/tire package also will result in more that just an increase in HP?specifically, it will improve handling and some might say the esthetics. Finally, the run flats and factory wheels would be available for use?say on trips. I am assuming that the throttle body will not be sold when the 545i is disposed of.
6. Similarly, consider the cost, for example, of a B&B exhaust. The cost if installed by a BMW dealer, after a 10% discount on the part, is about $1,063. The related flywheel HP gain is about (10 RWHP / .85) + (30 lb. weight savings / 10) = about 15 HP. The cost per HP is ($1,063 / 2 / 15 = about $35.44 assuming the exhaust can be sold net eventually for half of its cost (about $532).
7. Together, all the costly weight savings, plus actual HP gains from the related items, gives a net cost of ($1,433 + $685 + $532) = $2,650. The cost per HP is $2,650 / (13 + 9.4 +15) = $2,650 / 37.4 = $71?which is similar to the per HP cost of the throttle body, itself.
8. So, the 545i ends up with 325 + 37.4 = about 362.5 flywheel ?HP.? If one throws in the 37 / 10 lb. saving from removing the spare tire, then the 545i?s flywheel HP is about 366?which is not too shabby. Thus, either way, one ends up with performance in the 550i range and is much better off not buying a comparable 550i if he or she already owns a 545i (i.e., consider loss on 545i and probably non-discounted or higher discounted price of 550i, price increase on 550i, etc., etc., and etc.) (ignoring the other new features of the 550i--which mean nothing to me).
The final cost per flywheel HP is $2,650 / (37.4 + 3.7) = $2,650 / about 41 = about $65?but no spare in the car.
Phew. I?m tired; I?ll keep checking my calculations?later. Any thoughts?
[snapback]172125[/snapback]
I think the result is very good; I am sure that I can feel a fairly distinct difference before and after all the changes. And, I really like the looks of the wheels and tires. Money well spent. I've posted the pic below in the parts, mods, etc., dicussion. But, here it is again. I like it.
[snapback]184299[/snapback]
Do you think your throttle body has made any perceptible difference? I have been thinking about it. One thing that I have done (and actually went with JDN one night) is take it out to an 1/8 mile track and get the actual run time. I would love to know yours.[/quote]
Hi derricki just read your post regarding you and JDN going to the 1/8 mile strip.what were your times? Just curious as i have times from a 1/4 strip(terrible weather day).Have conversed with JDN in tha past and enjoyed his posts
[/quote]Yes, and I have posted my 1/8 mile times on "my" current G-meter thread.
01-06-2006, 11:53 PM
#69
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Originally Posted by Bokke' post='195509' date='Nov 8 2005, 10:34 PM
why did it take me so long to read this post
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me.. ....forget it, I've tried and just refuse to give up the "cold suds"
Cheers,
great info.....if I recall, my SSR's were about 8lbs lighter on the front and about 10lbs lighter on the rears,
At 6'5" / 245lbs, my greatest HP gains could be me..
....forget it, I've tried and just refuse to give up the "cold suds" Cheers,
Weight Savings from Wheels: 2[(34 ? 22.5) + (32 ? 22.5)] = 42 (BMW Style 101 19" wheels versus Sport package 18" wheels)
Weight Savings from Tires: 2[(32 - 25) + (29 ? 25)] = 22 Michelin Pilot Sport 2's versus Dunlop Run Flats
Wheels/Tires--Total Weight Savings: 64
Equivalent Sprung Weight Savings: 2(22) + 1.5(42) = 107
Weight Savings from Removing Spare: 35 (Addition of Mobility Kit Offsets Removal of Jack)
Weight Savings from B&B Exhaust: 30
Total Equivalant Sprung Weight Savings: 107 + 35 + 30 = 172
Flywheel HP Equivalent = 172 / 10 = 17.2 (i.e., 10 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [(3,814 - 172)] / 325] - (3,814 / 325) = 11.206 - 11.735 = -.529
or, approximately, equivalently:
Change in lbs. / HP ratio = [3,814 / (325 + 17.2)] - (3,814 / 325) = 11.146 - 11.735 = -.589
To equate the two,
Flywheel HP Equivalent = 172 / 11.2 = 15.35 (i.e., 11.2 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [3,814 / (325 + 15.35)] - (3,814 / 325) = 11.206 - 11.735 = -.529
Take your choice.
[/quote]
Bump
03-04-2006, 08:28 AM
#70
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Originally Posted by Znod' post='220404' date='Jan 7 2006, 03:53 AM
Thanks Bokke. There is no requirement for you to go on a crash diet. ~{;^)
For anyone interested, here is where I think I ended up--all in lbs.
Weight Savings from Wheels: 2[(34 ? 22.5) + (32 ? 22.5)] = 42 (BMW Style 101 19" wheels versus Sport package 18" wheels)
Weight Savings from Tires: 2[(32 - 25) + (29 ? 25)] = 22 Michelin Pilot Sport 2's versus Dunlop Run Flats
Wheels/Tires--Total Weight Savings: 64
Equivalent Sprung Weight Savings: 2(22) + 1.5(42) = 107
Weight Savings from Removing Spare: 35 (Addition of Mobility Kit Offsets Removal of Jack)
Weight Savings from B&B Exhaust: 30
Total Equivalant Sprung Weight Savings: 107 + 35 + 30 = 172
Flywheel HP Equivalent = 172 / 10 = 17.2 (i.e., 10 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [(3,814 - 172)] / 325] - (3,814 / 325) = 11.206 - 11.735 = -.529
or, approximately, equivalently:
Change in lbs. / HP ratio = [3,814 / (325 + 17.2)] - (3,814 / 325) = 11.146 - 11.735 = -.589
To equate the two,
Flywheel HP Equivalent = 172 / 11.2 = 15.35 (i.e., 11.2 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [3,814 / (325 + 15.35)] - (3,814 / 325) = 11.206 - 11.735 = -.529
Take your choice.
Bump
For anyone interested, here is where I think I ended up--all in lbs.
Weight Savings from Wheels: 2[(34 ? 22.5) + (32 ? 22.5)] = 42 (BMW Style 101 19" wheels versus Sport package 18" wheels)
Weight Savings from Tires: 2[(32 - 25) + (29 ? 25)] = 22 Michelin Pilot Sport 2's versus Dunlop Run Flats
Wheels/Tires--Total Weight Savings: 64
Equivalent Sprung Weight Savings: 2(22) + 1.5(42) = 107
Weight Savings from Removing Spare: 35 (Addition of Mobility Kit Offsets Removal of Jack)
Weight Savings from B&B Exhaust: 30
Total Equivalant Sprung Weight Savings: 107 + 35 + 30 = 172
Flywheel HP Equivalent = 172 / 10 = 17.2 (i.e., 10 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [(3,814 - 172)] / 325] - (3,814 / 325) = 11.206 - 11.735 = -.529
or, approximately, equivalently:
Change in lbs. / HP ratio = [3,814 / (325 + 17.2)] - (3,814 / 325) = 11.146 - 11.735 = -.589
To equate the two,
Flywheel HP Equivalent = 172 / 11.2 = 15.35 (i.e., 11.2 weight savings yields a one HP increase)
Change in lbs. / HP ratio = [3,814 / (325 + 15.35)] - (3,814 / 325) = 11.206 - 11.735 = -.529
Take your choice.
Bump