Can of worms- which one is all around better for upgrades 84-87, or the 88? (Page 3/3)
pmbrunelle NOV 06, 12:19 PM
I thought that the hp ratings were steady-state, so flywheel inertia wouldn't affect the ratings.

I remember handling external balance and neutral balance Fiero flywheels (both probably aftermarket jobber units), and they seemed similar, but I didn't have the foresight to weigh each one.

I thought the difference in hp ratings was simply unexplained.

[This message has been edited by pmbrunelle (edited 11-06-2019).]

Flying_Dan NOV 06, 12:47 PM

quote
Originally posted by Spadesluck:

or just put an 88 cradle in it. Very good compromise between the years.



This is what I'm doing. I found a nice 85'GT with 3400, but an AT (yuck). I've sourced almost all the pieces from an 88'GT with 5spd and will convert my 85' to the 88' rear cradle and 5spd.

I think it depends, if you can find a good example of an 88', get it. If you already have an earlier model, there is potential to update. Either way, lots of fun projects to get into.
Gall757 NOV 06, 12:55 PM
I was told that there was a change in the EPA testing methods which used a lower RPM for the sample test. I am trying to confirm that explanation, but it may take some digging.

I can see where flywheel weight may affect a torque rating, but not HP.
Will NOV 06, 04:03 PM

quote
Originally posted by pmbrunelle:

I thought that the hp ratings were steady-state, so flywheel inertia wouldn't affect the ratings.




Right. OEMs use brake dynos which use essentially steady-state RPM compared to a dynojet which measures rate of acceleration of a known load.

There are many speculations about why the horsepower rating changed.

[This message has been edited by Will (edited 11-06-2019).]