What's the max top speed a thirdgen can handle???
02-12-2004, 11:41 AM
#51
Supporter/Moderator
iTrader: (7)
Join Date: Feb 2001
Location: Cincinnati, OH
Posts: 13,347
Likes: 0
Received 425 Likes
on
326 Posts
Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Originally posted by f-crazy
ohhh ok i see what you mean...my speedo goes to 140 so i was wondering at what rpm the speed would be....
ohhh ok i see what you mean...my speedo goes to 140 so i was wondering at what rpm the speed would be....
02-13-2004, 01:54 AM
#53
Supreme Member
iTrader: (1)
Join Date: Apr 2000
Location: Northern CA.
Posts: 5,321
Likes: 0
Received 4 Likes
on
4 Posts
Car: '82 Z28
Engine: 350
Transmission: TH400 4,000 stall
Axle/Gears: Currie 9", 4.56 gears
112 so far since the engine swap. Did 124 mph a few years ago when I had 3.08 gears and the 305 
02-15-2004, 08:11 PM
#54
Senior Member
Join Date: Dec 2003
Location: Newberry, Mi
Posts: 539
Likes: 0
Received 0 Likes
on
0 Posts
Car: transam, el camino
Engine: 415
Transmission: T56
The stock steel driveshafts in out cars are prone to fail at speeds over 150mph, I don't think you want that happening.
02-16-2004, 11:03 AM
#55
Supreme Member
iTrader: (8)
Join Date: Jul 2001
Location: New Boston, IL, USA
Posts: 3,204
Likes: 0
Received 6 Likes
on
6 Posts
Car: '90 Formula 350
Engine: 383 SBC
Transmission: ProBuilt S/S 700-R4 & ACT 9" Stall
Axle/Gears: 10 bolt 3.23
That's with 3.23s gears or so. If you're running 3.42s... 3.73s you will approach that critical speed faster.
02-16-2004, 12:12 PM
#56
Supreme Member
iTrader: (-1)
Join Date: Mar 2002
Location: SE Michigan
Posts: 1,728
Likes: 0
Received 2 Likes
on
2 Posts
Car: Bright Red 91 GTA
Engine: CARBED LT4
Transmission: MK6
Originally posted by ShiftyCapone
Well if you have a 255 tire (I saw that you used 245 in your calculation but stated previously that you had a 255). You can use the next equation down in the calculator section, and in 5th gear (.63) with a 3.42 rear and a 255/50/16 tire I get 3971 rpm or right around 4k for 140 mph.
Well if you have a 255 tire (I saw that you used 245 in your calculation but stated previously that you had a 255). You can use the next equation down in the calculator section, and in 5th gear (.63) with a 3.42 rear and a 255/50/16 tire I get 3971 rpm or right around 4k for 140 mph.
as far as the driveshaft is concerned,...with 3.42's the speed at which "critical DS speed" is reached is at 134mph....and about 120 she starts making weird harmonics lol....
02-16-2004, 07:51 PM
#58
Supreme Member
Join Date: Sep 2002
Location: Elk Grove Village, IL
Posts: 2,967
Likes: 0
Received 0 Likes
on
0 Posts
Car: 1989 TransAm GTA
Engine: One sweet modified 355 TPI.
Transmission: The kind that shifts....
i used 245 becasue that what the car came with..and at 143 mph the tach is right around 4,500...
as far as the driveshaft is concerned,...with 3.42's the speed at which "critical DS speed" is reached is at 134mph....and about 120 she starts making weird harmonics lol....
as far as the driveshaft is concerned,...with 3.42's the speed at which "critical DS speed" is reached is at 134mph....and about 120 she starts making weird harmonics lol....
02-16-2004, 08:57 PM
#59
Supreme Member
Join Date: Dec 2003
Location: Newark, DE
Posts: 2,391
Likes: 0
Received 0 Likes
on
0 Posts
Car: '86 Camaro, '02 WRX, '87 K5, '67
Engine: 350 TPI, 2.0turbo, 383 in the works, 289-4BBL, 232, A-head 4-cylinder
Transmission: T56, 5-speed, 700R4, C4, T176, semi-auto 2-speed
Axle/Gears: 3.73, 3.90, 4.88, 3.55, 3.54, 7.00
That depends on the diameter of the tube, the length of the tube, and the exact alloy used.
02-17-2004, 12:54 AM
#60
Supreme Member
iTrader: (3)
Join Date: Jan 2004
Location: Las Vegas
Posts: 2,716
Likes: 0
Received 252 Likes
on
188 Posts
Car: 1987 Formula (original owner)
Engine: 305 TPI
Transmission: T5
Axle/Gears: 9-bolt/3.45
Great topic, and fun reading! I've only had mine up to 125--with the tops off, lol.
It was on a long, flat section of freeway somewhere in AZ. I could see ahead for miles, and there were no cars anywhere, so I went for it. But once I caught up to some traffic and passed it like it was parked, I decided I better slow down, lol.
The rush(what a rush!) comes after you slow down! I'm sure my blood pressure would've broken the doctor's gauge, lol.
It was on a long, flat section of freeway somewhere in AZ. I could see ahead for miles, and there were no cars anywhere, so I went for it. But once I caught up to some traffic and passed it like it was parked, I decided I better slow down, lol.
The rush(what a rush!) comes after you slow down! I'm sure my blood pressure would've broken the doctor's gauge, lol.
02-17-2004, 11:12 AM
#61
Supreme Member
iTrader: (-1)
Join Date: Mar 2002
Location: SE Michigan
Posts: 1,728
Likes: 0
Received 2 Likes
on
2 Posts
Car: Bright Red 91 GTA
Engine: CARBED LT4
Transmission: MK6
Originally posted by FruityOne
Anyyone know at what speed the Aluminum drive shaft reaches critical rpm?
Anyyone know at what speed the Aluminum drive shaft reaches critical rpm?
the 1LE DS has a critical speed of 154 IIRC
02-18-2004, 11:25 AM
#63
Supreme Member
iTrader: (8)
Join Date: Jul 2001
Location: New Boston, IL, USA
Posts: 3,204
Likes: 0
Received 6 Likes
on
6 Posts
Car: '90 Formula 350
Engine: 383 SBC
Transmission: ProBuilt S/S 700-R4 & ACT 9" Stall
Axle/Gears: 10 bolt 3.23
I'm guessing the spohn is a lot higher since it's suppose to be a lot beefer. Course with add'd strength of Steel means it's gonna weigh more than an LS1 aluminum. Course I'm just guessing anyone got a spohn DS?
02-18-2004, 11:53 AM
#64
Supreme Member
Join Date: Dec 2003
Location: Newark, DE
Posts: 2,391
Likes: 0
Received 0 Likes
on
0 Posts
Car: '86 Camaro, '02 WRX, '87 K5, '67
Engine: 350 TPI, 2.0turbo, 383 in the works, 289-4BBL, 232, A-head 4-cylinder
Transmission: T56, 5-speed, 700R4, C4, T176, semi-auto 2-speed
Axle/Gears: 3.73, 3.90, 4.88, 3.55, 3.54, 7.00
A chromoly driveshaft probably doesn't weight that much more than an aluminum one. The critical speed for chromoly is significantly less than aluminum though. Carbon fiber still has the highest critical speed.
Considering the packaging limitations of the torque arm and the portly demeanor of a street going 3rd gen I'd opt for either chromoly or mild steel. Mils steel has a critical speed that is about 1,500 RPM higher than chromoly, but it is significantly heavier.
Considering the packaging limitations of the torque arm and the portly demeanor of a street going 3rd gen I'd opt for either chromoly or mild steel. Mils steel has a critical speed that is about 1,500 RPM higher than chromoly, but it is significantly heavier.
Thread
Thread Starter
Forum
Replies
Last Post
NBrehm
Engine/Drivetrain/Suspension Parts for Sale
1
08-25-2015 11:49 PM
1992 Trans Am
Engine/Drivetrain/Suspension Parts for Sale
1
08-08-2015 08:16 PM
