Home
About Us
Calendar
Fiero Documents
Merchandise
Tips
Links
Members
Message Board
Other Fiero Clubs
VIN Decoder
Speed Calculator
GFC Facebook Page
 
« previous next »
Pages: 1 2 [3]

Author Topic: 2.8 vs 3.4  (Read 20127 times)

0 Members and 2 Guests are viewing this topic.

GTRS Fiero

  • Hero Member
  • *****
  • Posts: 12,510
  • It is what it is.
    • View Profile
Re: 2.8 vs 3.4
« Reply #30 on: October 12, 2017, 05:43:35 pm »
Maybe I'm confused, but does the stock 2.8 run out of HP or RPMs at 123MPH?  Changing the motor from a 2.8 to a 3.1 shouldn't change the redline, but of course the HP and torque would be greater.  I would think that this would be offset, somewhat, by air starvation at higher RPMs.
Logged

Fierofool

  • Global Moderator
  • *****
  • Posts: 10,745
    • View Profile
    • Georgia Fiero Club
Re: 2.8 vs 3.4
« Reply #31 on: October 12, 2017, 06:00:29 pm »
Torque equals acceleration.  Horsepower equals speed. 
Logged
There are three kinds of men:

1.    The ones that learn by reading.
2.    The few who learn by observation.
3.    The rest of them have to pee on the electric fence and find out for themselves.    Will Rogers

TopNotch

  • The Duke of URL
  • Global Moderator
  • *****
  • Posts: 3,984
    • View Profile
Re: 2.8 vs 3.4
« Reply #32 on: October 12, 2017, 06:05:30 pm »
The type of transmission would affect your top speed. With a TH-125, RPM's would limit top speed.
Logged
The more complex the mind, the greater the need for the simplicity of play.

GTRS Fiero

  • Hero Member
  • *****
  • Posts: 12,510
  • It is what it is.
    • View Profile
Re: 2.8 vs 3.4
« Reply #33 on: October 12, 2017, 07:00:57 pm »
Ron768 stated he has a 4-speed.  With the additional horsepower, will he get more speed?  At some point, air intake, frontal resistance, traction, redline, and gearing conspire to limit your top speed.
« Last Edit: October 12, 2017, 07:03:13 pm by GTRS Fiero »
Logged

Fierofool

  • Global Moderator
  • *****
  • Posts: 10,745
    • View Profile
    • Georgia Fiero Club
Re: 2.8 vs 3.4
« Reply #34 on: October 12, 2017, 07:28:56 pm »
I didn't necessarily say that.  Horsepower will give you speed.  There is a limit to all horsepower where it starts to fall off.  I had my first 85GT up to an estimated 123 mph.  Having an 85 mph speedometer, I just looked at where the hand was pointing when I decided to back off.  I then placed a piece of paper over the gauge when I got home and marked off the 5 mph increments, rotated it to match up to the upper mph markings and extrapolated from there. 

My headlight doors never tried to open but the side windows started to vibrate from the wind buffeting.  And I thought my 17 year old daughter was going to penetrate the center console and arm rest with her fingers.  It was an open stretch of 4-lane with no cars in sight for a mile ahead.  I got a good half mile downhill run from highway speed, then it leveled out. 
Logged
There are three kinds of men:

1.    The ones that learn by reading.
2.    The few who learn by observation.
3.    The rest of them have to pee on the electric fence and find out for themselves.    Will Rogers

GTRS Fiero

  • Hero Member
  • *****
  • Posts: 12,510
  • It is what it is.
    • View Profile
Re: 2.8 vs 3.4
« Reply #35 on: October 12, 2017, 07:34:20 pm »
Quote from: Fierofool on October 12, 2017, 07:28:56 pm
And I thought my 17 year old daughter was going to penetrate the center console and arm rest with her fingers.

LOL!  What were you teaching her?
Logged

Fierofool

  • Global Moderator
  • *****
  • Posts: 10,745
    • View Profile
    • Georgia Fiero Club
Re: 2.8 vs 3.4
« Reply #36 on: October 12, 2017, 07:38:41 pm »
That it's dangerous and stupid to run that fast on a public highway in a Fiero, I guess.  She was OK until the windows started rattling.  She was often my copilot at Run For The Hills.  And she could handle a Fiero, too. 
Logged
There are three kinds of men:

1.    The ones that learn by reading.
2.    The few who learn by observation.
3.    The rest of them have to pee on the electric fence and find out for themselves.    Will Rogers

ron768

  • Paid Members
  • *****
  • Posts: 336
    • View Profile
Re: 2.8 vs 3.4
« Reply #37 on: October 13, 2017, 08:58:25 am »
Top speed is controlled by several factors. Horsepower being just one of them. Drag is a big factor. Weight is another. Gearing is one. The conditions of the day also play in, temp, humidity , altitude above sea level. I worked at a bike shop that had a dyno. In the winter a bike would make more hp as opposed to what it would make in the summer. There was a really good test comparision run by Car and Driver between 2 corvette's back in the late 80's. A 68 against a 86. The 68 would out run the 86 up to its top speed no matter what the drivers did. The 68 had the 427 ci motor rated at 435 hp, the 86 had the 250 hp 350 from that year. The 68 was gear limited and ran out to about 145 mph. the 86 had gearing that allowed it to top out above 150 mph.
Logged
1985 2M6 SE, 1986 GT x 2.

GTRS Fiero

  • Hero Member
  • *****
  • Posts: 12,510
  • It is what it is.
    • View Profile
Re: 2.8 vs 3.4
« Reply #38 on: October 13, 2017, 03:46:02 pm »
Well, yeah, since the '86 spotted the '68 almost 200 HP.  If they had the same gearing, I wonder if the outcome would have been different.  If you compare similar HP Fieros with 410 final drive to those with 284 final drive, the 410 will win, to its top speed.
Logged
Pages: 1 2 [3]
« previous next »