bits of weight vs speed related info worth reading through

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
It is widely accepted in the automotive community that for every 100 pounds of weight lost from a vehicle the gain in acceleration felt would be like getting an extra 10 horsepower. Now remember, you are technically not “gaining” 10 horsepower. Your vehicle is accelerating at a quicker rate that is the equivalent “as if” you had gained 10 horsepower. This is an interesting note because many people erroneously believe that by dropping weight the vehicle is somehow producing more power. This is only true for dropping driveline weight as we have mentioned in the driveline for gas mileage section, not vehicle gross weight.
I've always been a bit amused at the fact that so few guys think things through carefully, before something breaks, and they are forced to look into why some part failed or why the car ran into some track barrier!
most newer guys are far more concerned with adding engine power, and tend to ignore the drive train strength, suspension control and braking capacity and endurance and durability.
Well that is of course, untill they are forced into looking at those factors by a combo of parts failures and having a car fail to go where the driver wants it to or slow down rapidly and consistently enough to prevent body work costs from getting out of hand when the car hits things it should have been able to avoid in the hands of a skilled driver.
related useful info
http://www.wallaceracing.com/et-hp-mph.php


http://www.tinindianperformance.com/Tin Indian Performance Pontiac Parts Catalog.htm

http://www.race-cars.net/calculators/et_calculator.html

http://www.xcceleration.com/et.calculator.html

http://garage.grumpysperformance.com/index.php?threads/how-fast-were-the-old-muscle-cars.1938/


http://garage.grumpysperformance.co...asonably-fast-in-street-trim.3404/#post-33377

http://garage.grumpysperformance.co...acing-info-lots-of-good-stuff.373/#post-52133

http://garage.grumpysperformance.co...-many-of-the-cars-desirable.11244/#post-50845

http://garage.grumpysperformance.co...wer-numbers-thats-important.10620/#post-45643

http://www.opticarmorwindows.com/


http://www.hotrod.com/cars/project-vehicles/116-9905-light-vs-heavy-wheels-comparison/

http://www.dragstuff.com/techarticles/weight-reduction.html

http://www.racingonthecheap.com/10-ways-to-loose-weight/

http://www.borellimotorsports.com/flashcast/tip9_weightshaving/tip9.html

http://www.hotrod.com/how-to/additional-how-to/113-0310-weight-reduction/


(weight vs part list I found on a different site)
12..ABS module
15..AC compressor
8.6.AC condenser
21..AC fan motor (entire assembly)
14..Airbag and bracket, passenger's
4...Airbag, driver's
.....Air dam
1...Air filter
6...Air Pump (w/brass fittings)
14..Alternator w/ bracket
3...Amp, Monsoon
3...Antenna, bracket, and motor if applicable
1...Ashtray & lighter
.....Blinker switch
2...Bolt lengths, extra
.....Brake pedal pad
16..Brakes, stock w/ caliper, bracket, pads
22..Bumper, front reinforcement and brackets
21..Bumper, rear reinforcement and brackets
41..Carpet & Sound deadening
50..Catback
15..Cats
8...CD Changer (stock)
10..Center console
.....Coating, under carpet
5...Coolant Overflow
4...Crossmember brace
7...Cruise control (w/cable, throttle cable cover, bracket)
11..Dash
6...Dash brace (steel)
5...Dash Pad
4...Dash Replacement
18..Door panel (TA, both)
5...Door panel (psgr)
1...Door panel insulation
15..EGR, air pump, & harware
.....Emblems
14..Fan (dual)
9...Fan (single)
.....Fan shroud
5...Fenders (Inner metal)
7...Firewall Insulation
13..Firewall Insulation w/ plastic
5...Floormats
3...Foglights and brackets
.....FRA mod
7...Gas, Extra (per pound)
23..Gas Tank (steel)
20..Gas Tank (plastic)
5...Gas Tank Evac Box
2...Glovebox
1...Grill insert
50..Hatch (w/ no glass)
60..Hatch (TA w/ high-rise spoiler)
40..Hatch (Firebird w/ molded spoiler)
4...Hatch cover
2...Hatch shocks
20..Headlights/metal frames
2...Headliner
4.4.Head unit (Monsoon)
.....Head unit/AC console trim piece
8...Heat sheilding
9...Heater core (w/water)
8...Hood Latch w/ brackets
1...Hood shocks
3...Horn
45..HVAC, complete system
3...Inner fenderwells, plastic
2...Intake Silencer
.....License plate brackets
2...License plate(s)
1...Lug Nuts (Chrome)
1...MAF
13e.Manifolds (stock)
4...Mirror/bracket
.....Misc. junk in the car like keys, garage remote, change, etc.
4...Overflow Tank
1...Owner's manual
3...Panels, under steering wheel
17..Panhard rod (TRZ kit)
5...Panhard rod brace, upper
.....Parking brake
.....Power brake booster
5...Parking brake handle
.....Power seat motor
3...Power steering cooler
12..Power steering pump, pulley, idler pulley
.....Power window motors
17...Radio (stock in center panel)
1...Rear view mirror
9...Seatbelts (rears and passenger's)
7...Seatbelt (front only)
37..Seat, driver's (cloth)
46..Seat, front (Trans Am leather)
31..Seat, front (Camaro leather)
30..Seat, passenger's (cloth)
41..Seat, passenger (Trans Am leather w/ lumbar pump)
28..Seats, rear (leather)
4...Seat mounts and brackets (rear)
3...Sheetmetal, extra double walled
1...Shifter ****
20..Side impact bars (doors)
37..Spare tire and jack
6...Speaker panels, hatch
5...Speaker panels, rear passenger's
15..Speakers
5...Speakers (mid-base Monsoon, pair)
5...Speakers (Alpine, pair)
18..Spoiler (Weight measured on a Pontiac)
.....Spring isolators
2...Sun visors
14..Swaybar and brackets, front
1...Swaybar metal attachment
.....Taillight(s)
12..T-Tops
2...T-Top holders
11..T-Top hump/sheet metal
3...TCS motor
.....Under car tow points
1...Washer fluid pump
9...Window motor/track
8...Windshield washer fluid
3...Windshield wiper reservoir
4...Wiper arms
10..Wipers/motor
.....Wiring, Excess
21..Y-Pipe (w/1 cat.)
2...Y-Pipe hanger (stock, connected to tailshaft)

Wallet mods
10e.A-Arms (BMR mild steel)
13e.A-Arms (stock)
3...Airlid, aftermarket
19..Alternator relocation kit (LT1, PS removal, Speed Inc.)
104.Aluminum Block (main caps, bolts)
33..Battery (Optima yellow top)
14..Battery (Odyssey PC680 dry cell)
40..Battery relocation (rear)
8...Brakes, Aerospace w/ caliper, pads
13..Carpet (Speed Inc., lightweight)
38..Catback system (Hooker)
3...Chromoly LCAs
3/9.Carbon fiber driveshaft
14..Chromoly A-arms
25..Chromoly K-member
23..Cylinder head (unassembled)
30..Door (no internals)
14..Door glass
34..Draglite wheels (15X10 w/tires no tubes)
.....Drag slicks or street slicks
.....Drilled axles
13..Driveshaft (aluminum)
17..Dry cell battery (stock location)
7...Electric water pump
7...Emergency brake items (handle/cables)
21..Exhaust (TD's dumped before axle)
37..Exhaust (TSP TD's w/ mufflers)
......Fiberglass door skins
35..Fiberglass hood
.....Fuel cell
18..Fuel tank (98-99) plastic
50..Hatch (rear) with no glass
25..Headers, Kooks 1 7/8
5...Header extensions (12" open headers)
52..Hood ('98-02 LS1 stock steel)
51..Hood ('00 SS)
45..Hood (stock LT1 SS)
23..Hood (Chaser carbon, no brackets)
15..Hood (VFN Sunoco pin-on)
13..Hood (Harwood 3" cowl)
10..Intake (LS1)
11..Intake (FAST 78)
25..Intake (BBK 85)
55..K-Member (Stock LS1 w/clamshell's & inserts)
20..K-Member (LT1 PA racing)
25..K-Member (BMR)
75..Lexan glass (Percy's speedglass FR, RR, & side windows)
30?.Lexan glass (rear window only)
.....Lightweight clothing
35..Lightweight brakes, front
48..Lightweight brakes, Strange front (w/spindle cutaway)
32...Lightweight brakes, rear
10..Lightweight flywheel
15..Lightweight springs and shocks (BMR)
.....Lightweight steering column
9...Lightweight steering wheel
6...Lower control arms
10..Manual rack and pinion steering
10..Manual Window
35..Mini-Tubbing
23..Muffler (SLP w/ tailpipes/tips)
5...Panhard Rod Brace/bar
.....Plastic fuel tank, late model
.....Powerglide, TH350, or M4 transmission
15..Racing seat
150.Rear-End (10-bolt, no fluid)
196.Rear-End (S60, dry, true trac)
74..Rear-End (Moser M9 housing)
40..Rear-End (Moser thru-bolt center section spool)
+64.Roll-Bar (8 pt chromoly)
+52.Roll-Bar (6 pt chromoly)
+67.Roll-Bar (6 pt mild steel)
10..Rotor, drilled/slotted
5....Rotor, single disk race w/ alum. hub
18..Seat (Kirkey 17" prostreet/drag w/ cover)
6...Seatbelt (RJS 5-pt harness, camlock)
15..Shocks (front Hal's/QA1)
.....Shortbelt mod
17e.Skinny front tires
25..Slicks (rear 275s)
12..Spindle (front)
41..Spindle w/ ABS hub (both for 93-02)
28..Spindle (Racecraft w/ hub both)
14..Spool (Strange)
11..Springs (stock WS6 rear)
35p.Springs / Shocks (front only)
12..Springs (Afco front 14" 275)
16..Springs (BMR lowering)
34..Springs (Eibach drag-launch, 4 w/ airbags)
18..Subrame Connectors (2)
17e.Tires (165/85/15 radial)
9ea.Tires (Moroso 17050)
12ozTires (MT 26/4.5 ET fronts)
19e.Tires (M&H Racemaster P185/75R15 fronts)
17..Torque Arm (stock M6)
21..Torque Arm (BMR full length adj)
20..TQ converter, small
.....Underdrive pulleys
12e.Wheels (Alumistar 15X10)
10..Wheels (Draglites)
8...Wheels (Bogart front)
10..Wheels (Bogart rear)
26e.Wheels (Greg Weld 15/3.5, 165/80/15 tire)
31p.Wheels (Weld RT-S 15X4 w/ MT 26" tire)
42e.Wheels (Weld Prostars, 28/10.5 tire)
56e.Wheels (Z06 17X9, 275 tire)
54e.Wheels (Z06 18X10.5, 305/35 Nitto)
48e.Wheels (Z06 Replica, 275/40/17 tire)
46e.Wheels (ZR1s, 26/11.5 ET streets)
9...Y-Pipe, off-road
 
Last edited:
http://www.edmunds.com/dodge/challenger/2015/srt-hellcat/features-specs/
hellcat
5450 lbs. 707 hp at 6000rpm'
=7.7 lbs per hp

ricks t-bucket
lets say 2000 lbs and lets conservatively say 470 hp
=4.25 lbs per hp

give both cars good traction and the results may amaze some guys
and keep in mind theres a great deal of potential power left, in that chevy small block, the engines built for great street response and durability not peak power

spending a couple hours reading links and sub-links would do a great amount of good here and help sort out the problems, keep in mind that its a SYSTEM, what goes in is locked into the calcs
and all the math and related factors are well known, and easily calculated based on displacement, cam timing , exhaust back pressure head flow, exhaust flow , etc.
volumetric.gif

exhaustpressure.jpg

EXFLOWZ4.jpg

137998aa.jpg

tubsed.png

expik.png

one of the most common and least tested, factors in most engine build ups is testing for restrictions to building increased horsepower. a huge problem is in restrictive exhaust systems that can not effectively allow the headers to scavenge the burnt gases from the cylinders, a good open collector on a well designed header can reduce the back pressure at the exhaust port to a negative pressure significantly increasing cylinder scavenging out the exhaust, thus helping draw in a fresh intake charge.
COMMON SBC INTAKE PORTS
felpro # 1204=Port Size: 1.23" x 1.99"=2.448 sq inches

felpro # 1205=Port Size: 1.28" x 2.09"=2.67 sq inches

felpro # 1206=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1207=Port Size: 1.38" x 2.28"=3.146 sq inches

felpro # 1209=Port Size: 1.38" x 2.38"=3.28 sq inches

felpro # 1255 VORTEC=Port Size: 1.08" x 2.16"-2.33 sq inches

felpro # 1263=Port Size: 1.31" x 2.02"=2.65 sq inches

felpro # 1266=Port Size: 1.34" x 2.21"=2.96 sq inches

felpro # 1284 LT1=Port Size: 1.25 x 2.04''=2.55 sq inches

felpro # 1289 FASTBURN=Port Size: 1.30" x 2.31" 3.00 sq inches

USE THE CALCULATORS, YOULL, QUICKLY FIND THE LIMITATIONS
http://www.rbracing-rsr.com/runnertorquecalc.html
http://www.wallaceracing.com/chokepoint.php
http://www.wallaceracing.com/header_length.php

the valve curtain area, cam duration and lift controlling that curtain area,or port cross sectional area will pose a restriction to air flow at some point,in the engines rpm band, but you can extend the effective air flow duration and efficiency with carefully timed exhaust scavenging, that helps draw in the intake runner inertia load of air/fuel,charge much more effectively if the peak negative pressure wave is correctly timed
portfl3.jpg

http://garage.grumpysperformance.com/index.php?threads/the-new-215cc-vortec-heads.266/#post-75012

http://garage.grumpysperformance.com/index.php?threads/carburetor-intake-manifold-test.58/

http://garage.grumpysperformance.com/index.php?threads/holley-accelerator-pumps-cams.1790/

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/holley-carb-power-valves.1639/

http://garage.grumpysperformance.com/index.php?threads/cooler-denser-air.8961/

http://garage.grumpysperformance.com/index.php?threads/car-falls-flat-in-third-gear.9326/

http://garage.grumpysperformance.co...-the-holley-4150-and-4160-series-carbs.10736/

http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/

http://garage.grumpysperformance.com/index.php?threads/is-backpressure-hurting-your-combo.495/

http://garage.grumpysperformance.com/index.php?threads/calculating-required-exhaust-pipe-size.11552/

http://garage.grumpysperformance.com/index.php?threads/building-an-exhaust-system-for-your-car.1166/

 
Last edited:
http://www.edmunds.com/dodge/challenger/2015/srt-hellcat/features-specs/
hellcat
5450 lbs. 707 hp at 6000rpm'
=7.7 lbs per hp

ricks t-bucket
lets say 2000 lbs and lets conservatively say 470 hp
=4.25 lbs per hp

give both cars good traction and the results may amaze some guys
and keep in mind theres a great deal of potential power left, in that chevy small block, the engines built for great street responce and durability not peak power
Rick is scared to Drag Race the T bucket.
Terminal Trap Speeds of 130-140 required ..No Race Rollcage and no 4-link rear.
The weight of the Hellcat keeps climbing.
Now 5,140 pounds.

I read last night its actually 4100 pounds with driver.
 
Hellcat has 780 HP.

On the Mopar Forums the Hellcat has ran 10.4 @ 132 on street tires.
10.2 on Drag Radials.
 
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