Can a stock 2.8 car hit 150mph?
What can a stock Duke car do?
I suppose you'd want a 5 speed?

quote Originally posted by 2.5: Can a stock 2.8 car hit 150mph? What can a stock Duke car do? I suppose you'd want a 5 speed?

1. With a JATO bottle strapped to the roof
2. Explode
3. Yes

I've had the needle buried at 120 before, but I doubt the 2.8 could hit 150 mph

Part 1
https://www.fiero.nl/forum/A...030531-1-024961.html

My wife's 4 cyl starts to get in the red at 90 so I don't let it hang there too long.

Edit: 1984 4cyl 4 speed.

[This message has been edited by Marine1981 (edited 03-26-2012).]

quote Originally posted by Marine1981: My wife's 4 cyl starts to get in the red at 90 so I don't let it hang there too long.

The red on the tach? Must be the 4 speed?

Yep, I just edited that. I was gauging my speed with a GPS app on my phone.

My 85 2.8l effectively runs out of transmission about 7000 in 4th, puts me around 130? Rides real nice around 100, just don;t like speeding tickets anymore.

The TA once, and only once, saw a cool 170 on a backwater Alabama highway :-D

[This message has been edited by spc15tdime (edited 03-26-2012).]

quote Originally posted by 30+mpg: Part 1 https://www.fiero.nl/forum/A...030531-1-024961.html

Seems 130 is probably optimistic in the 2.8, maybe 105 in a Duke?

quote Originally posted by spc15tdime: My 85 2.8l effectively runs out of transmission about 7000 in 4th, puts me around 130? Rides real nice around 100, just don;t like speeding tickets anymore. The TA once, and only once, saw a cool 170 on a backwater Alabama highway :-D

7000 on a 2.8?! No way. It would blow up if you ever got that high.

It probably should have, that was years ago when I was dumb and didn't know rods could break. Not so much these days, of course now the engine is built for higher revs. Still don't take it that high anymore.

quote Originally posted by mattwa: 7000 on a 2.8?! No way. It would blow up if you ever got that high.

Exactly, the only way to get 7k on a stock 2.8 is to go from redline and DOWNSHIFT to a lower gear. Easy peasy! lol

quote Originally posted by BV MotorSports: Exactly, the only way to get 7k on a stock 2.8 is to go from redline and DOWNSHIFT to a lower gear. Easy peasy! lol

Respectfully I disagree, if you push the gas pedal long enough it will get there, mine did anyways, took some time, but it'll do it, once at least.

quote Originally posted by spc15tdime: Respectfully I disagree, if you push the gas pedal long enough it will get there, mine did anyways, took some time, but it'll do it, once at least.

Once is right, then you'll be walking home.

I would think the 2.8 would float the valves long before 7K rpm.

Buried needle once, hit 120 a couple times, but the auto runs the revs pretty high at that speed.

quote Originally posted by spc15tdime: Respectfully I disagree, if you push the gas pedal long enough it will get there, mine did anyways, took some time, but it'll do it, once at least.

Never seen a stock Fiero do it, because I haven't been STUPID enough to try. But I am sure the rev limiter would stop you long before 7k.

[This message has been edited by BV MotorSports (edited 03-26-2012).]

quote Originally posted by BV MotorSports: Never seen a stock Fiero do it, because I haven't been STUPID enough to try. But I am sure the rev limiter would stop you long before 7k.

Nope... The rev limiter is factory set at 1.34 million RPM, from what I've read here.

I've hit 117 (on gps) with the automatic in my 85 GT. Was still pulling pretty well, but that engine most likely isn't quite stock. My daily, by comparison, will pull well past that point. Technology has moved a long way.

quote Originally posted by BV MotorSports: rev limiter would stop you long before 7k.

Tell that to what remains of my old 2.8...

And I have video of my GT hitting a bit over 130 with a 3.4. Racing a newer Dodge Viper. I don't show the speedo but it is pretty obvious we're going VERY fast, haha.

SKIP TO 1:38

[This message has been edited by TheRealShadowX (edited 03-26-2012).]

Various magazines tested the 84 Fiero with the four speed performance transmission (4.10:1) and ran out of steam at 103 MPH (Car & Driver and Road & Track Sept '83). The '84 econo trans was never tested by any of the magazines that I have, but given it's mechanical disadvantage it's top speed would likely be even lower.

In Nov '84 R&T tested a four speed V6 and found the top speed to be 125 MPH

In Oct '87 R&T tested a Formula with the Getrag and V6 and found the top speed to be 125 MPH as well.

Almost stock 2.8 with speedo pegged.



------------------


Currently being upgraded at Whodeanie Customs with many TLG Automotive parts

www.yellowfiero.com Pictures Modifications

[This message has been edited by yellowstone (edited 03-26-2012).]

quote Originally posted by Bloozberry: Various magazines tested the 84 Fiero with the four speed performance transmission (4.10:1) and ran out of steam at 103 MPH (Car & Driver and Road & Track Sept '83). The '84 econo trans was never tested by any of the magazines that I have, but given it's mechanical disadvantage it's top speed would likely be even lower. In Nov '84 R&T tested a four speed V6 and found the top speed to be 125 MPH In Oct '87 R&T tested a Formula with the Getrag and V6 and found the top speed to be 125 MPH as well.

I have been at exactly 100mph (gps measured) in my '84 with econo trans. My duke is completely stock, but still well maintained and pretty fresh for its age. ( I.E. new delco wires, delco plugs, documented / religious oil changes.. no oil leaks anywhere, great compression, and zero blow by or smoke on start up.)

I don't think that was all it had on a flat surface but I really did not have the nerve to stay at that speed much longer. (Troopers are everywhere) I am also not trying to say it had a lot left either. I.E. 105mph would not be out of the question, but im not willing to put money on it

As most know, the 4cyl speedo will go past 85mph and pass the trip odometer if you have enough straight road in front of you. I know the econo trans will reduce some of the top end punch but once you get to speed it shouldn't be much different then the 5spd isuzu. Did any of the magazines do a top speed on an 85-88 4cyl?


------------------
1984 Base Coupe Red Stock MY8
1984 SE Black Stock

2002 Grand Prix GTP 40th Anniv. Stock

[This message has been edited by lurtz (edited 03-26-2012).]

I have hit 100 (going downhill a bit probably helped) and then backed off mighty quick as my tac was getting up there. It was an 86 2.5 5 speed with the gt gauges. I can say I have done it, but doubt I want to do it again unless its on a straightaway with a guarantee of no police around like the slat flats or something.

[This message has been edited by tbone42 (edited 03-26-2012).]

quote Originally posted by lurtz: Did any of the magazines do a top speed on an 85-88 4cyl?

After the V6 model came out in 85, none of the magazines were interested in testing the 4 cylinder models... or at least none of the 23 articles from major magazines contained in Brookland's Books Pontiac Fiero 1984 - 1988.

My 86 se with the 2.8 and a modded computer can do 137... bit that is everything the poor girl has.

Everything I've seen with any credibility says the stock 2.8 is good for 125-126.

At 85 MPH my 2.8 Auto sounded like a Kawasaki Ninja so put a 4 speed auto in it. The top speeds are more limited by transmissions and gear ratios. Now I get 2800 RPM at 100 MPH. Haven't had the money to risk taking it faster.

------------------
Project Genisis Lo Budget 3800SC swap

88 formula 3.4L 4t60 swap

[This message has been edited by hercimer01 (edited 03-27-2012).]

It will do 150 i have been off needle in 4th so another gear would make 150 car doesn't shakes to bits. Duke probably would come close off clock 120 and 5 speed is only good for top speed the advantages of 5 speed is better 0-30 in 1st and 2nd and a higher top speed but for everyday driving your never going to use 5th gear.

Ok here are the rough numbers.

Stock V6 is about 125mph give or take 6mph for transmission.
Modified V6 limit is about 150 with nitrous and a custom motor.
Stock 84-85 4cyl is about 98mph with a stick, 93mph with an auto.
Stock 87-88 4cyl is about 105 with a stick 95mph with an auto.

Fastest stock Fiero was the 85GT V6 4spd. Slowest stock V6 Fiero was I am sorry to say, the 88GT 5spd.

Now take into account, these are all 25 plus years old, which means the factory top speed number are useless. Who knows if the engine is modified or stock, or worn out. There are flook cars out there that I have driven that felt like they were 3.1's not 2.8's. Pulled amazing compared to any other Fiero. We have 2 guys in the club that took their 2.8's bored and stroked them to 3.2 liters. Externally they look identical to the stock motor, but they sure haul A$$ a lot better. Your best way to find your speed is get a GPS of some sort. Smart Phone, TomTom, Garmin or USB GPS for your laptop and go for a drive on a deserted stretch of road, hopefully with a chase car to follow you if something does go wrong so they can call for help in case you are not conscious.

My 85GT with a 2.9 V6 custom pistons, 10.5-1 compression, bigger cam, decked heads that had also been ported. Plus a lot of other mods, including a 100hp nitrous shot. I had left the track for the day but still has the NOS bottle in the trunk and it was open. I hit the freeway around 1am and had no other cars around. So I decided what the hell lets go for it. I ran 2nd-3rd without the bottle, when I hit 4th, I let her rip. Once the engine hit a tick over 6100rpms I lifted. Speedo was so far off the scale it was useless. So I did the math and it was 151mph. The bad side of it. Running the nitrous for that extreme amount of time. Probably close to 30 seconds wide open. I managed to crack a piston.

Oh rev limiter on all 85-87 V6 Fiero's is 6200rpms, only the 88's had the rev limiter removed.

Now for some odd facts.

The Econo trans is actually the best top speed trans as when you are getting close to that 125mph barrier the econo trans puts the rpms about 4900 right dead in the power band for the V6. Instead of the wheezing area around 5500. The Isuzu hooked to a V6 is the next best thing for top speed runs.
When I had my 2.9 motor hooked to an Econo trans and not using the nitrous 130-135mph was my top speed.

I am currently building a new car for a top speed run. This time we are going to be running an altered body which should help. I want to run 150-160mph. Its a nitrous assisted 4.9 V8 hooked to a Getrag 5spd and a 6 puck race clutch to handle the torque. Tires are a fairly short 225/50/16 overall tire height is only 24 inches. All the vents and scoops are there to keep air from building up in place the rad compartment, and the extra tall spoiler is to help get the air out of the deck lid via the rear scoop to keep the engine cool. The brakes right now are nothing special, Grand Am on the rear and stock up front, but I will be upgrading to Lebaron rears and Grand Am on the front.

Either way when I do this run, I'll at least 2 GPS devices watching the speed and I plan to have a video camera in the car filming it all on a mount just about my right shoulder, showing the dash and the GPS display.

There is a HUGE difference between 125mph and 150mph.

Here is the car as it sits now.



------------------
857GT Part 85GT Part 87GT Part Caddy, 93 Eldorado 4.9, 5spd Dual O2 Custom Chip, Custom Exhaust. MSD Everything Now with Nitrous. Capt Fiero --- My Over View Cadero Pics Yellow 88GT 5spd Full Poly Suspension, Lowered 1/2" in front, Corner Carver.

[This message has been edited by Capt Fiero (edited 03-27-2012).]

quote Originally posted by Capt Fiero: Ok here are the rough numbers. Stock 84-85 4cyl is about 98mph with a stick, 93mph with an auto. Stock 87-88 4cyl is about 105 with a stick 95mph with an auto. ...

and the 1986.....200mph right!!

quote Originally posted by Capt Fiero: Oh rev limiter on all 85-87 V6 Fiero's is 6200rpms, only the 88's had the rev limiter removed.

Yeah, I've gotten carried away and hit the rev limiter a few times, not while going for top speed but winding it out going through the gears. Probably saved my engine.

I've drag raced my nearly stock Fiero against my Audi A-6 with a V-8 and they ran even up to about 80 mph then the Audi would start to pull away . . . quickly (the Audi's rated top speed is 186mph).

The fastest I've has the Fiero was about 110. It handled well (maybe felt just a little light), no headlight popup. However, I didn't realize I was going that fast and slowed as soon as I looked at the speedo.

edited to remove photo.
------------------
Jim Martin
White '86 GT
Monterey, California

[This message has been edited by Jim_Martin29 (edited 03-27-2012).]

I think the fastest I have ever been in my life (which doesn't say much) is 90-95mph...Too many damn cops around here...

The fastest I've gone on the street (deserted highway) was about 125 mph many decades ago in an old 1963 Falcon hotrod with a high-performance small block V-8. The fastest I've gone on a motorcycle was about 140 on a custom chopper I built, also many decades ago. I was looking for the top end but got smart (scared) before I found it.

My 87GT with 86 engine, and Getrag 5 speed reached upwards of 120mph. my speedo was buried and my tach was reaching 5000rpms before I let off the gas. it took a little bit to get that fast, but with the amount of time it took to slow down, I would have to think I was 125-130mph. My 6 has only minor mods, nothing major. Really I feel the car is a dog, and really needs more power.

But for a stock 6, 120-125 is a safe bet for a 5 speed, however when I had a 3 speed auto, I could only get it to 105ish.

edit: HOWEVER! You shouldn't be worried about the top speed, its quite dangerous to go that fast! Especially in antique cars! Unless you're a race car driver on a race track, I wouldn't reccomend testing how fast you can go. It can carry jail time if you do it on the street.

[This message has been edited by Racing_Master (edited 03-27-2012).]

quote Originally posted by skuzzbomer: Nope... The rev limiter is factory set at 1.34 million RPM, from what I've read here. I've hit 117 (on gps) with the automatic in my 85 GT. Was still pulling pretty well, but that engine most likely isn't quite stock. My daily, by comparison, will pull well past that point. Technology has moved a long way.

Granted I have not driven a stock v6 Fiero in nearly 5 yrs, and I suffer from CRS (cant remember sh*t), but I am fairly confident that v6 Fieros have a stock rev limiter just below 6k IIRC.

------------------
Whodeanie built 1988 Fiero GT, loaded, 14k original miles, 5MT w/ LSD, built 3800 swap, PT67 turbo, w2a charge-cooled, whodeanie headers, tune & cam. ----400-500whp?????? More mods when I get it back. Stay tuned!
1987 Fiero GT Road Racer. 1st documented 3.4TDC swap- built in 1994. 5MT Isuzu, Quaife prototype LSD, HT Tubular A-arms, Fully poly & Heim jointed suspension, Custom 3 way adjustible sway bars, HT Bump Steer kit, Koin's, 320# springs, GA brakes, ZEX N20 and more! Under full restoration.
2007 Toyota Tacoma Double cab Prerunner SR5
2009 KTM 250SX

I read someplace that only 88's didn't have rev-limiters, pre-88's did, and it was set too 6200 RPM.

[This message has been edited by mattwa (edited 03-28-2012).]

Sounds about right right Mattwa. But I cant remember even running one of my Fiero's that high. The just don't make any power up top. lol

I seem to accidently peg the speedo every time i'm on the highway.

------------------
Turbo 3800 E85 5spd spec5
11.54@132.7

When I ran my 1/4 mile run with the stock 2.8/3-speed automatic, WOT it shifted at 6000RPM, or just under. It shifted into 3rd just as I passed the 1/4 mile line. But I agree, running them up that high stock is pointless.

It ran a 16.939@79.98mph BTW. Yes it was slow. That 2.8/3-speed is long gone. Funny thing was I beat a stock 87 trans am that day...

And it would be difficult to peg my speedo, at 160mph.

[This message has been edited by mattwa (edited 03-28-2012).]