whats the top speed of an 83 z28 camaro with a 700-r4 auto and stock gearing off the show room floor im just wondering. both the lg4 and the l69

i think i herd some ware that teh stock 86 i rocs would do 149 tapped out and i wanted to know how far the 83 z28 lg4 and l69 camaros were behind this or how close they are.

 

I think this is more of a General question so I'm going to move it to the General engine board.
There are some calculators where you enter your redline and gearing and it tells you the top speed before aerodynamics comes heavily into play I'm sure someone will be able to direct you to them.

 

I had a 84 Z28 HO and I remeber that the speedo stopped at 85. I dont think it would go much faster than that unless you had a chip to overide the govenor.

 

i here the results that you get by doing it that way are no tright at all im talking all stock right off of the show room floor what would these cars do on top end both the lg4 z28 and the l69 prefably the 83-84 models

 

i never herd of the z28 lg4 and l69 coming with a governer limiter i thought they would go much faster then that i here about people doing 90-100 in there v6 camaros all the time so you would think that the lg4 and expecialy the l69 would do alot better then that.

 

wats the highest mph soem one has had a eather 83-84 lg4 or l69 z 28 up to with mild mods or stock???

i got my car durring the winter and was only able to test drive it last summer while i had a permit and i wasnt able to take it past 60 mph but other then that it drove very well and was very power ful but i havent had teh chance at all to see what it has on yop end being its winter teh car is off the road and all.

 

I know that Z28 was stock!

 

that seems to me to be very rong still i dont see how a z28 with a l69 ho in it could only do a little over 85mph
i ised to have an 84 sport coup that ran liek **** and was gutless and i could get that car up to about 90-95 mph and that was all stock with a 2.8 carbed.
so u see ware im getting at here unless the ho had soemthing way rong with it then it should be able to go way past 85 mph

 

157mph with my LG4 and 5 speed. I used an RPM calculator since my speedo didn't work at the time.
5,000rpm in 5th gear.
Oh, and it took quite a bit of time to get up there, 5th pulls really slow.

 

is there anything done to it to get it to do 157 mph ???

that sounds pretty dam good for a lg4 to me!!!!!!

 

Carb, intake, air cleaner.

 

what gears do u have in the rear end by looking at my sig below adn nowing that my car is an auto with a 700r4 what do u think mine will do on top end and i might ad it has 373s adn runs like a top

hooker headers
true duals
40 series flo masters
edolbrock performer series rpm intake
carter competition series carb
crane cam
373s
high flow summit air filter
excell spark plug wires
lowered 2 inches if that makes a difference
car runs liek a top what range do u think she will be in on top end

 

I'd say my '83 could easily do at least 125mph. I havent tried any top speed runs, but i'd say it should do at least that, maybe even 140 with 5th gear.

 

yeah thats what i liek to here, does any one have a gesstamate on how fast my car will be able to do on top end???

 

I had 3.27 gears in the back.
Your 3.73's will limit your top end, but you should be able to hit close to 130-145 if not faster

 

just sounds a little to good to be true that a car i own could acualy get up to the 150 mph mark.

 

just because a cars speedo says a certain max speed, that does not mean thats how fast the car can go. it has nothing to do with the top speed of the car....

ps. there was no speed limiter on the L69 or the LG4....

 

thats wat i thought also i didnt think they put a limiter on the lg4 and the l69 it wouldnt realy seem right if they did they built the car for power and speed why would they want to limit it.

 

Well, here's what I know:
I used to watch a show called "Police Videos". A 305 Caprice (well I assume it was a 305) was caught on Police Radar...going 120. That's a 4000 lb car eith driver -easy. My old 403 Olds powered Cadillac would do about 120. My 89 2.8 Corsica would do about 105-110. I know: different engines. But this should give you somewhat of a basis.
My Crown Victoria with a 302 can do around 110. That's a guess, since I have an 85 mph speedometer. The reason I have that guess comes down to my experience against heavy duty trucks and sport utilities. As you probably know, most diesel and heavy duty gasoline trucks--like the F350, not semis--are governed at just under 100. The same goes for quite a few SUVs, though some stop at 110 or around that area. When you start to pass an F350 and he floors it...you're pulling slowly, his engine continues to roar a high RPM, yet you're suddenly passing quickly with your speedometer topped out.....you know you're doing quite a bit over 100.
I don't know how much that will help since that part was a Ford 302 with an AOD and 3.08 gears, but I hope somehow...it does.
You know, passing a dangerous *** that tries to trap you in the other lane is a quick way to find out what your car can do...but I suggest you try your best to avoid such a situation.
Take it easy. By the way, I second the 125-130 mph top for the stock LG4. That sounds VERY logical to me.

 

what about with mild mods like my car i am assuming my car is an lg4 and not an l69 because i looked at teh tech articles an they say that in 83 the ho l69 only came in the camaros with 5 speeds and mine is an aoutomatic so i am asuming my car is an lg4. so with the mods that i have mentiond above what do u think ill be looking at.

on another funny not before i bought my car the owner sed it did have an HO l69 in it you dont no how pissed i was when i read the tach artivals on here and found out that it cant be and it must be an lg4 but i am not that mad because my lg4 has a good amount done to it to ware it should be putting out more pony and pounds then an l69 any way with whats doen to it si far i actualy dont even no what it has for pistons in it eather but the engine was rebuilt 3500 miles ago and the ariganal owner sed that it had higher compression pistons in it then it did have in it so i am still trying to find out he seems to thinks he remembers that they are 10.1 pistons with teh rest that i stated that is doen to it earlyer.
and i do no that he is not just telling me that it was rebuilt i was actualy at the shop and seen it being done.

 

Just cause your motor is an LG4 doesn't mean your not putting out the same horses as an L69.
The biggest difference between the two is the L69 had flat top pistons and a little better cam.
You said you seem to remember 10.1 commpresion on your pistons. That is about the same if not a little higher than the L69. So I'm guessing that when this guy told you that you had the H.O. motor, thats because with the mods, it was upgraded to an H.O. motor.
I have an 84-Z28 with the L69 and a 5-speed. The engine had over 100,000 miles when I baought it and i still was able to top out at 140MPH. I had a digital speedo in at the time that registered that high.
So My best guess from what you are telling us is you should be able to hit some where between 135 to 150.
With the 3.73's in the back I would say closer to 140 to 145, but again, I am just guessing.
Also the best way to tell if your engine is an L69 is look at the back of the block. You may not be able to see it. It should say 5.0L G on the block. The G signifies the L69 motor.

 

my stock LG4 83 Z28, i took it over 110 a few times, about 115, its also auto, everything is stock i have 3.23 gears an a peg leg.

but i still have the rear end, same gears but a trans go shift kit and corvett servo in the tranny stock convertor

the engine puts down 213rwhp and 307rwtq and i was having fun with a friend the other day and im guessing i took it to about 150mph or so and was still pulling, this was in a few miles, and trying not to bottom out since i have 3inch true duals and a 1inch drop so its pretty low. but i only have the 85mph speedo i was about 5k on revs, how fast do you think i was going, im guessing about 135 to 147mph some where in there, can someone tell me??

 

is the tranny gear number correct, i used the Haynes hand book to get it, it says 4th is .7 but whats OD is it the same or different, if its the same then this is correct.

MPH
Tire Radius RPM Rear End Ratio Transmission Gear Ratio

12.75 5,000 3.23 .7



=MPH
167.83029001074112

 

I can't verify the use of governors, cause I know I don't have one, or any type of "G" code or what-not, but I'm running a L69 VIN 7, w/3.73's, and I know at 70 MPH, my RPM's are around 3000. Redline is 5500 for L69's, and a little less for the LG4's.

I would not expect my car to acheive 145 MPH. I could be wrong, but I don't think so.

 

I dont know about the 83's top speed but i clocked my brothers top speed stock 86 Z28 LG4 auto at 220kph "no clue what that is in miles" and I clocked FastEddy's stock 85 Z28 LG4 5-speed top speed at 210kph. Both there speedo's die out at 140kph. My speedo goes to 240kph, which is how i clocked them. Another friend also clocked them in his 90 IrocZ and got the same top speeds.

As for the HO, other then the obvious on the vin #, if your car was to come with an HO the Z28 emblem on the dash say's "Z28 5.0L High Output" right inside the car and of course when u pop the hood it says it on the breather and has the dual snorkels. I had an 84 auto with that set up.

 

L-69 with 373 and auto overdrive good for about 135, and thats it unless the trans has been moded to keep it in overdrive over 90mph

 

Zephyr, no offense, but that seems a bit high for a lightly modded LG4 putting out probably 170 horse max. Or was it with a different motor?

Ive had my 2.8 to about 100. It wont go much faster. My Trans Am hit 85 with the LG4, never pushed it, but was nothing special on the highway. Now with the 350, it rips on the highway. Have had it to 4200 rpm in 3rd, not much, but it just pulls. Probably doing 105 or so. Im afraid to take it up into 4th, I have nothing to really gain by it and a lot of risk. Probably do around 150 now with my mods Im guessing. A stock L98 car would do like 150 or so, correct?

 

how many other peeps here think my car will be in that range with the mods mentioned above.
there was a kid looking at this with me that owns a civik that was saying a bunch of crap about you guys and how u dont no anything about cars if you think that are cars will go that fast.

 

the kid with the civik is the same kid that sed his all stock honda civik will beat my car no matter what just because it has a five speed and mine doesnt .

 

My L69 car would do about 133 mph when it was stock.

Just FYI, the HP requirements increase with the cube of the speed, assuming laminar fluid flow. That's the third power for you non-math types.... double the speed, the HP requirement is multiplied by 8. These cars (or any street car for that matter) don't exhibit laminar fluid flow over their bodies, so the requirements are even steeper than that. And of course, keep in mind, that's the HP at the speed in question, not just the motor's peak HP on a dyno at whatever RPM it happens to be at.

To get one of these over about 145 HP with anything even dimly resembling a stock motor, especially something with no top end like a TPI motor, is mighty tough, though I won't say impossible. There's alot more to it than running down the highway at 80 and seeing that you're doing 3000 RPM, and saying "Well my 'redline' " (whatever that word means) " is 6000, so my car will do 160". I don't think so.

Since most people have absolutely no way of measuring this, it's one of the easiest ways there is to generate lots of monkey-spank from the inexperienced. In the case of the kid with the Civic, just nod and smile and say "uh-huh", and move on. It's not worth arguing with an idiot over something like that. Then when you talk to him about it, accidentally slip and call it a Sentra or a Tercel or a Festiva, and if he reminds you it's a Civic, tell him you can't tell the difference, all those little sub-compact grocery carts look the same in your rear-view mirror anyway.

 

yeah i guess the only real way to find out the top speed of my car woudl to go out and see what it will do my self the only prob with this is cops are jerks over here and there realy isnt any good places to do it that arnt already patroled my cops heavily already.

so i was trying to get an idea of what i should be able to expect from my car this summer with out actualy haveing to find out my self and risk recking or soemthing i alwase have my friends ask me how fast it will go and cant ever give them a strate answer and ive also wondered what she will do. but i guess it all comes doun to just going for it and finding a strate back road soem ware and seeing what it will do my self.

 

My L69 is pretty heavily modded. It has a .480 lift cam with 230/230 duration, ported factory heads, 10:1 compression, port matched intake, no emissions equipment at all and headers. Also a K&N for what it's worth. Exhaust is dynomax piping with flowmaster muffler and no cat. it's a 5 speed with 3.73 gears.

I went 5000 rpms in 5th gear with a 26 inch diameter tire. I think that's about 147 or 8. It probably coul have pulled another 2 or 300 rpms but it was nearly out of nuts.

I truly estimate my car to run high 13s to low 14s though i've never had it to the track. 157 is hard to believe for a lighlty modded LG4. Are you sure you factored in the correct tire diameter?

 

Tom:

That works out to about 142, assuming your tach is accurate which it probably isn't, every one of these I've ever had reads high to a greater or lesser extent. The one in the car right now is the most accurate one I've seen; it's only about 200-250 RPM high at 5000.

If yours is off by 250 RPM at 5000, then you were actually doing 135.... right about what a car like yours should do.

 

Hmm ... maybe it is just me but don't you SANE folks think that any street car that can do 130 mph is MUCH faster than you need to go???

It is EXTREMELY dangerous to be going that fast on a public highway, unless you are crossing Saskatchewan on the TransCanada somewhere between Moose Jaw and Maple Creek.

Please, folks, don't risk your (or anyone else's) life by doing those things

 

when my car was a 2.8/w auto i had the speedo pointing straight down one time, you where it says MPH

btw it has the 85 mph speedo and had 3.23's

didn't have a tach at the time so ur guess is as good as mine on actual speed

with the v8 it is definately capable of more speed but i am limited my my stick bottom end and needing diferentvalve springs

 

As usual..... RB's right. Wind resistance, air density, altitude, air temp., and a whole lot of other things also dictate top speed.

The only way to tell is take it out and run the monkey. Catch the guy that killed your mom!!

When I was younger (i.e. lived with ma' and pa' and could afford $250/mo insurance) I had a '94 Z28. 275HP LT1 with a 6 speed. Only mods were a Flowmaster muffer, and a K&N filter. I read too many 'Motor Trend's and 'C&D's that said the car would do upwards of 150 mph. I thought I had to prove them right. (Never again BTW :nono: ).

I know the 4th gen is more 'streamline' than the 3rd gen but they're about the same weight. I burried the 150 speedo in 5th, and true to the word, once I hit 6th gear it was down to ~135 mph. So you'd have to be putting out something near that much HP to do the same.

LG4??? No. Not without some serious mods.

It's kinda cool to say I've gone that fast (since the other 99% of the world hasn't), but it was more 'pee-pee your pants' than anything. Not something I want to do on a public road again.

 

No offense taken. It was the LG4 with an Edelbrock 1406 carb, 7101 Intake, and the open element air cleaner and K&N, MSD HEI Coil.
Car ran a 14.97 @ 91.67mph, which I think is great for an LG4 with 113K miles on it. Car would easily pull to 120-130, then 130 to whatever speed 5K at 5th gear is took quite a bit of highway.

 

For some reason, I think our cars are more aerodynamic than the 4th gens. HP becomes a main factor at 130mph.
200hp nets us 160, 300hp will net us 180mph, 600hp nets us 200mph.
Numbers might be slightly off (too laxy to check them)

The 4th gen will get to 150mph faster due to the higher stock HP rating, but they have a hard time once they reach 155-160mph.

Another example is my friends 95 Supra TT. It has 395rwhp and I have gotten it up to 160mph a few times and it was still pulling.

 

I would have agree, but you are speaking greek to this bunch

 

Well I could be wrong about the top speed? My 84 Z28 HO that I crashed was pretty quick but once my speedo topped out it did not seem like it was going anywere. The Engine just seemed loud. I guess I would not know what I was topping out at unless I had my tech 2 hooked up to it to actually give me a accurate reading. I know my 92 RS has a govenor because everytime I hit 110 the car kick down automaticly!!!

 

RB- well i suppose the 5000 was a guesstimate, I didn't want to take my eyes off the rapidly passing freeway. Shouldn't my car go much faster than a stocker? Yours went 133 factory.

 

Probably not too much faster. It's not like you have 10% more HP, so you go 10% faster; it's more like you have 10% more HP at the speed in question, so you go 2% faster.There's alot of things that eat up power at high speeds that aren't linear; tire rolling resistance, and air drag are the 2 big ones.

Really, the body ends up determining the car's top speed to a far greater degree than the engine. The way to increase it isn't to put in more power, because it takes such a massive power increase to make a significant improvement; it's to work on lowering drag, and improving stability. Air resistance involves alot more than your eye's perception of the body's "gracefulness", which is why a Lamborghini Countach looks like it would have low CD, but in fact is literally as aerodynamic as a brick wall. The car's "effective frontal area", the amount of air that gets trapped underneath the front of the car, the air that gets caught in the wheel wells, the windshield angle, the shape of the rear of the car and how smoothly the air can flow around it and rejoin itself after the car has passed through... pretty hard to evaluate some of these things without a wind tunnel.

 

Good points, the other variable I left out is the 5th gear ratio. I used the smokemup.com calculator and they automatically put in I think .74 for the 5th gear. I think the T5 came with several ratios, some were even .63 if I recall correctly.

One would think that one thridgen camaro would be very similar to another regarding wind resistance. I understand the squares and cubes involved with speed and wind resistance, but you are right about the other variables, such as drivetrain losses and rolling resistance. I am running cheapo tires!

 

Absolutly NOT!
I used to take my old '79 T/A to 140+ at least once a week, had my IROC to 130+ (140 speedo ) many-a-time. The trick is not to do those kinds of speeds on roads that have traffic and make sure you know the road well so no surprises will be waiting further down. Speed doesn't kill, ignorance does.

 

if i put a ls1 lt1 or ls6 with a 6 spd into my 84zl69ttop and put the head light covers on wat will my topspeed be and 0-60 times

 

Because it came with non speed rated tires from the factory.

 

according to my uncle it can do 175mph with nothing more then a cam for an 82 z-28

oh yeah beats everything on the road also even vettes and stuff

 

Don't you believe it.

 

what?? he also thiks he walked on water

 

Well I went to the calculator that they have here on thirdgen and it says that is the radius of you tires is 17 inches and you are at 5500 rpm, with 3.73 ratio, and .70 overdrive ratio on you tranny that hypothetically speaking you could go about 213 mph.