kb58
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| posted on 12/8/06 at 01:28 AM |
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Yeah I've see a few posts claiming V8s are so light. I think it comes down to how they're weighing it. For example, quoting weight of a
V8 but not mentioning it's a short block... things like that.
A website showing engine weights would should be helpful, but ONLY if every component was listed. I'd do it but don't have the access to
a wide variety of engines. It would have to be someone who works at a wrecking yard.
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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locostv8
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| posted on 12/8/06 at 03:16 AM |
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http://www.mustangworks.com/articles/misc/EngineWeights.html
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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ERP
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| posted on 12/8/06 at 06:17 AM |
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I think what kb58 is trying to say is that it's difficult to compare weights without apples to apples comparisons. And often the weights are
quoted without context.
I find the 318lb Rover 3500 weight to be a bit dubious when on the same chart an all aluminium 2.5 duratec weighs 360lbs.
Ignoring the difference in block weight for a minute, a V8 has twice as many cylinder heads, twice as many cylinders and connecting rods, and a
heavier crank. For the same material it's going to be considerably heavier.
Having said that it has more displacement and generates more power as a result.
I love big engines hell I have a poo load of money in the tuned ford 302 I'm using in my car, but there is no free luch your trading off power
for wieght.
I do believe that a well built V8 locost can still be light (relatively speaking) and have a good weight balance, but a bike engined car will be
lighter (likely with less power).
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locostv8
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| posted on 12/8/06 at 07:40 AM |
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Please don't get me wrong, I'm not trying to say that a V8 powered car will be as light as a BEC. Though the rolling chassis will be at
the point you remove the front part of the 2 piece driveshaft because it would be using the same components as the BEC This would more than offset
slightly heavier tubing(at least Derman which is a successful BEC). Due to aftermarket support you can get good aluminum heads for reasonable and
with these you can get the Windsor near the weight of many of the "acceptable" 4 cyl. The 315s I will be using for street use cost $107
from tirerack.com and weigh 30lbs which is 6 lbs more than a 225. Since you are using an engine that will make at least 400 hp with a cam and good
heads you don't need a high strung engine.
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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DIY Si
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| posted on 12/8/06 at 07:52 AM |
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I don't think the rolling chassis will be as light as a bec. Since a bec has, to put it one way, more revs and less torque, the chassis
doesn't need to be as stiff. However, a big lazy v8 based chassis would probably be heavier due to the extra triangulation/strengthening it
would need to counter the high amounts of torque.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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locostv8
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| posted on 12/8/06 at 08:22 AM |
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Again, I'm defining the rolling chassis to be everything but the engine/trans/radiator. The Deman BEC uses the SAME spindles/brakes/ rear axle
assy and uses a rather long 2 piece driveshaft with a mid bearing and mount. Changing the long steel 2 piece drive shaft for a short almuinum one
should offset the slightly heavier tubing. Something I will also be doing is, with the same size rotors, convert to aluminum PBR 2 piston calipers
allowing about a 33% reduction of the weight of the spindle/brake assy. Actually I will probably buy the front and rear A arms from Deman.
[Edited on 12/8/06 by locostv8]
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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Tobynine9
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| posted on 12/8/06 at 01:16 PM |
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quote:
Originally posted by carsonp
yeah ill definitly be doing a +4 maybe more depending on the rear end.
I found that most D44s go for no less then $1500, which is pretty spendy, but... maybe its worth it, i dont know.
Whats the other option for IRS? The supercoupe? how much do those run?
And that price is typically for just the housing and gears, often not even the rear cover/bracing. You can get a full Dana 36 with half shafts,
control arms, leaf spring, housing, rear cover, etc (everything) for less than $1k.
The Dana 44 weighs about 20 lbs more. Seems to me a good ring and pinion set at the proper gear ratio on the 36 and you'd be fine as long as
you're not doing 6k rpm clutch dumps.
[Edited on 12/8/06 by Tobynine9]
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locostv8
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| posted on 12/8/06 at 07:55 PM |
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I just bought a MK VIII aluminum diff complete with a pair of 00 Mustang spindles with hubs and a pedal set off the 00 for $125. The 8.8 is about 30%
stronger than the D45.
[Edited on 13/8/06 by locostv8]
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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carsonp
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| posted on 13/8/06 at 03:36 AM |
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Well now im not sure if IRS is really the best way to go...
trying to hook 350hp and almost equal tq to a IRS in a 1600lbs car? A solid might be the way to go just cause it can hook better. I dont know.
I would like IRS. But added weight, money and less traction makes me think otherwise...
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kb58
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| posted on 13/8/06 at 04:47 PM |
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quote:
Originally posted by carsonp
Well now im not sure if IRS is really the best way to go...
trying to hook 350hp and almost equal tq to a IRS in a 1600lbs car? A solid might be the way to go just cause it can hook better. I dont know.
I would like IRS. But added weight, money and less traction makes me think otherwise...
Traction isn't a problem with IRS, just set the control arms to be the same length so there's zero camber change.
Added weight? Maybe 20lbs due to the CV joints. Money? Yes it would be more. BUT, you get a much better sprung-to-unsprung wieght ratio, necessary
for a decent ride and so the tires stay on the road. With some camber gain you also keep the tires square to the road in a turn.
What you are describing seems to be a drag-car; is that what this is? If so it'll be a bullet, but don't expect to walk away from someone
in a lighter car mid-corner, especially if there's bumps.
[Edited on 8/13/06 by kb58]
Mid-engine Locost - http://www.midlana.com
And the book - http://www.lulu.com/shop/kurt-bilinski/midlana/paperback/product-21330662.html
Kimini - a tube-frame, carbon shell, Honda Prelude VTEC mid-engine Mini: http://www.kimini.com
And its book -
http://www.lulu.com/shop/kurt-bilinski/kimini-how-to-design-and-build-a-mid-engine-sports-car-from-scratch/paperback/product-4858803.html
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carsonp
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| posted on 13/8/06 at 09:04 PM |
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Its not going to be a drag car, or race car. It will see both, but rarly. The main goal is a fun street car.
Id still like IRS... So maybe ill plan on that for now.
Thanks
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Tralfaz
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| posted on 16/8/06 at 01:24 PM |
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quote:
Originally posted by locostv8
Please don't get me wrong, I'm not trying to say that a V8 powered car will be as light as a BEC. Though the rolling chassis will be at
the point you remove the front part of the 2 piece driveshaft because it would be using the same components as the BEC This would more than offset
slightly heavier tubing(at least Derman which is a successful BEC
Well perhaps that is partially true, but most BEC's dont need to be built as a +4 chassis to begin with.
My R1 BEC will weigh between 850-900 lbs. 700 lbs less than the proposed V8 car under discussion.
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carsonp
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| posted on 16/8/06 at 11:20 PM |
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quote:
Originally posted by Tralfaz
quote:
Originally posted by locostv8
Please don't get me wrong, I'm not trying to say that a V8 powered car will be as light as a BEC. Though the rolling chassis will be at
the point you remove the front part of the 2 piece driveshaft because it would be using the same components as the BEC This would more than offset
slightly heavier tubing(at least Derman which is a successful BEC
Well perhaps that is partially true, but most BEC's dont need to be built as a +4 chassis to begin with.
My R1 BEC will weigh between 850-900 lbs. 700 lbs less than the proposed V8 car under discussion.
no kidding? 
I need a +4 not only to fit the motor, but im 6'3" 230lbs so ill need a few extra "s to fit semi comfortably
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leto
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| posted on 17/8/06 at 09:31 AM |
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The book frame is 3” wider and the driver compartment 4” longer than a Lotus 7 S2. But for some strange reason (ask Ron) the book frame is 1”1/4 lower
then the Lotus. So big feet might be a problem otherwise i believe you will be fine in a book frame, specially a left hand drive one. A car like this
should be a tight fit, scrambling around in the corners is very uncomfortable and tireing.
“I'm gonna ride around in style
I'm gonna drive everybody wild
'Cause I'll have the only one there is a round”. (J. Cash)
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Angel Acevedo
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| posted on 6/3/07 at 07:42 PM |
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quote:
Originally posted by locostv8
This is a +4 chassis 302 with a 302 T5, According to the builder it is 1250 and 50/50.
........... I am replacing 1x1.5x11ga(.125) where 1x1x16ga is called for and 1x1x14ga where .75x.75x16ga. ........
LocostV8,
Please confirm 1" X 1.5" X 11 Ga.
This is not available in mexico.
Will 1.5" X 1.5" X 11 Ga be OK?
Or is it a bit over the top?
Thanks in advance.
Beware of what you wish.. for it may come true....
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locostv8
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| posted on 6/3/07 at 08:25 PM |
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Time has passed and more components have been collected producing a bit of spec drift. I will be building 2 7s. First will be named Put-put will be
traditional with clamshells and the specs are 302/C4(AOD?)/MK VII 8.8. This will be my wifes car, who is NOT a car person, with a target of 275 to
300 hp and good road manners. The second, Shagnasty, will be built along the lines of the Lotus type three seven. The specs on this are a bit over
the top using MN12 knuckles/roller 392(351W)/dry sump/aluminum heads/ EFI/Lakewood sshield/ Aluminum Fwheel with twin disk 7.25 clutch/T5(hopefully
Gforce dogface)/IRS using 03 Cobra and MKVIII pieces/95 Cobra Rs front 17x9 with 255 40 17s and rear 17x10.5 with 315 35 17s.
The first chassis, Put-put, is intentionally OTT with material strength and will be pretty much a road car for a non car person figuring that the
small additional weight will be made up by the power to weight ratio. 11 ga is .125 or 1/8th and I would think should be available most places. The
use of this is intended to allow basically a Cage to be built around the tub area partialy for intrusinon protection. As I'm building Put-put I
will probably debate and possibly revise the materials to use on Shagnasty. An additional thing I'm doing is using steel sheet welded to the
chassis including fill welds to the diagonals then a light coating of Linex( polly bedliner) to seal and further strengthen, I also don't like
the prospect of spending most of my spare time polishing aluminum.
Specs are still subject to drift but at this point I have nearly all the components on hand and hopefully will shortly be making sparks. An
additional consideration for me is that I have a defibulator/pacemaker and can't do electric welding. I have a Miller stick/mig/tig welder but
have to bring in someone to do the chassis welding and the primary pepole I know are stick welders.
Hope this helps. A thread you might want to watch is Rods 5.0 build http://locostusa.com/forums/viewtopic.php?t=1586
[Edited on 6/3/07 by locostv8]
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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Aloupol
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| posted on 6/3/07 at 11:05 PM |
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quote:
Originally posted by DIY Si
...Since a bec has, to put it one way, more revs and less torque...
This has nothing to do.
A bike engine has less torque and more revs, at the crank. At the wheels, the toque is about the same between two cars with about the same
power and weight. Actually the wheel torque is the amount the tyre can afford.
Remember power = torque x revs.
[Edited on 6/3/07 by Aloupol]
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Angel Acevedo
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| posted on 7/3/07 at 12:44 AM |
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LocostV8,
My question is on the size, you state 1 X 1.25, in Mexico only 1.25 X 1.25 X 14 Ga or 1.5 X 1.5. in 14, 12, 11 and 9 Ga.
Thanks again.
Beware of what you wish.. for it may come true....
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locostv8
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| posted on 7/3/07 at 01:22 AM |
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The first chassis is 1x1.5x11ga and 1x1x14ga. The second will probably be 1x1.5x14ga and 1x1x14ga. I would think 1.25x1.25x14ga should work quite
nicely though.
[Edited on 7/3/07 by locostv8]
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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Angel Acevedo
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| posted on 7/3/07 at 03:36 PM |
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Thanks LocostV8,
1.25" X 1.25" X 14 Ga. will be.
Beware of what you wish.. for it may come true....
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Angel Acevedo
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| posted on 12/4/07 at 10:14 PM |
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quote:
Originally posted by Angel Acevedo
Thanks LocostV8,
1.25" X 1.25" X 14 Ga. will be.
After some tinkering, and due to the condition of local streets and roads decided that 1.5" 14 Ga. would be better for longer chassis life.
Cutting of the steel has begun taking Mcsorley 7+442 as a basis and modifying to suit the increased tube size.
I am willing to document the build for future builders if someone points me on the right direction.
Cheers to all
Beware of what you wish.. for it may come true....
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locostv8
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| posted on 13/4/07 at 06:34 AM |
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You should probably look at http://locostusa.com/forums/index.php since donors would be more similar. They have a section for builders log which
would be a good place to document build. The 91 Cougar would be a good donor car it is kinda the pieces I am using with a few others thrown in for
good measure. Look at http://www.deman-motorsport.com/build.htm those pics use a MN12 for front knuckles and rear IRS pieces.
http://wrangler.rutgers.edu/gallery2/v/7slotgrille/hssss/
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Angel Acevedo
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| posted on 13/4/07 at 01:37 PM |
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Doing that too, I just want to return to locostbuilders.uk a little of what i`ve learned (Spelling?) from the site
Beware of what you wish.. for it may come true....
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