I've been slowly adding mods to my '88 Formula auto for the last three years and keeping track of the improvements. The car has 51K miles on it and it's about an 9 out of 10 for overall condition.

I have a flat, straight SAFE spot near my rural home where I can do some drag test. it's about 3/4 of a mile long with a fire hydrant JUST ABOUT at the 1/8 mile mark. Of course it's not an actual drag strip but I can use it to compare engine mods and also from car to car for my own edification.

For instance I had a Chevy Tracker that barely hit 60MPH, an '89 Mustang 5.0 that hit 88 MPH and an 06' Lincoln LS that reaches 92 MPH over that same distance.

The Fiero hit 67 MPH when I first brought it home. Then I started fiddling:

( All of these runs were made at least three times with about 1/2 tank of fuel, power braked to 1800 RPM and auto shifts )

Underdrive pully - 67 MPH (+0 )
Ported exhaust - 68 MPH (+2 )
Ported UIM and throttle body - 71 MPH (+2 )
Low restriction cat - 71 MPH (+0 )
Hypertech Chip - 72 MPH - (+1 )
Weight reduction of about 80 lbs - 72 MPH (+0 )

So everything combined added up to +5 MPH.

Then I added the 1.6 rockers.

The first two runs I made with the auto shifting and I hit 78 MPH. ( +11)

I could feel such an improvement at the top end I manually shifted and let the RPM's reach 5200. ( I know, the tach is not all that accurate ).

I hit 80 MPH ( +13).

Now I know all this is subject to debate. Fuel weight, outside temps, driver technique, the lack of actual time measurements and probably a few other issues that could fog the issue. However, something very noticeable has occurred with addition of the 1.6 rockers even if the numbers aren't indicative of anything concrete. Seat of the pants, I can feel the added power in the upper RPM's.

Pretty happy today.

I'm considering putting in 1.6s when I replace the valve stem seals.

What's the low end, up to 55 mph gain? IOW, does all the power come on with a major rush at the end or can you feel it throughout your acceleration?

What's the change in MPG? I'm not a big fan of visiting the gas station, so this is a concern.

Does the engine sound louder or quieter or smoother?

Where did you get your rockers?

BTW, '88 GT 5-speed with 7730 ECM.

quote Originally posted by pgackeman: What's the low end, up to 55 mph gain? IOW, does all the power come on with a major rush at the end or can you feel it throughout your acceleration? What's the change in MPG? I'm not a big fan of visiting the gas station, so this is a concern. Does the engine sound louder or quieter or smoother? Where did you get your rockers? BTW, '88 GT 5-speed with 7730 ECM.

There doesn't seem to be any improvement below about 2500 RPM. The power doesn't exactly rush, I mean this is a lowly 2.8, but you do notice the difference from 2500 to 5200 with steady acceleration. I haven't gone over 5200 RPM but at that point I felt the engine still had something left.

I think in a manual equipped car you'd really like the new found power. I have an auto so to feel the difference I have to keep the trans in 2nd. We have a lot of 30 - 45 MPH curvy roads around here and it's really made driving the car a lot more fun.

I have no data for MPG as I'm still on the first tank. I don't expect this tank to last too long what with 2nd gear driving. Once I get it out of my system I'll collect some data on the MPG.

The exhaust note isn't louder but it is different. Seems a little higher pitch but not at all unpleasant.

I bought the combined kit of rockers and pushrods from Jegs.

[This message has been edited by RayOtton (edited 05-23-2016).]

quote Originally posted by pgackeman: I'm considering putting in 1.6s when I replace the valve stem seals... Does the engine sound louder or quieter or smoother?

Check out my two page 1.6 roller-tip rocker installation thread Here... includes multiple videos of how it sounds.