73-87chevytrucks.com
General Site Info => General Discussion => Topic started by: 1979C20 on January 16, 2011, 06:52:56 pm
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Last night on the way home from sycamore creek, I opened 'er up on the empty highway. I hit a top speed of 111mph on flat ground and maxed out my engine at 5050rpms. Kept her thetr for a good 3 miles or so. No issues. No oil pressure drop. Stayed at 200°f. What are your guys top speeda and max rpms at that speed? This is a 79 c20 woth a 350, qjet, headers, glasspacks dumped umder the cab with 4.11 gears and 265/75/16's.
EDIT: SM465 tranny, too.
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Lol 74 in my 79. But you have to use a GPS to get a good reading
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ive had mine to 120 with the 31s gps checked was at about 4400 in 3rd/drive th350 trans 3.42 gears.
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had mine at 70 on the speedo once. (33" tires, so really about 75 or so) for about 20 seconds. that was a white knuckle ride!! tach'ed about 2500. th350 with 3.08 gears :(
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My buddy was driving my truckwhile I was following him, he had 115 with the 250, 3pd. Lol I think that's all it had too
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You let someone else drive 115 in your truck? Must be a good friend!
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Let's just say I let him borrow it.... He got an earful. lol
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I used a gps speedo on my phone. I pushed my pedal as far it would and the rpms topped out at 5050 and couldnt go any faster sadly. Its 4spd manual.
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Back when my 86 was on the road 85mph with 33's and a manual tranny, That motor wouldn't turn much over 4k rpms.
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I have a 1980 250ci with a 1bbl holley carb... 3.08 final drive... 255-75-15 on the back, reached 81m/h. I still need 4 more to travel in time......
Measured with GPS
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I'm gonna have to get a gps to figure mine out, the speedo bounces too much and with smaller tires its not correct. It says I've been over 100 but I estimate it to be more like 85-90.
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Do you have a cell phone? If so, how new is it? The new Android phones have all kinds of apps and I downloaded the free GPS Speeso app.
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<----- you see from my profile pic the fact that a '79 speedo is buried at 100mph. I did that on I-95 coming from Washington D.C. w/ the 383 and 3.08 rear on stock size tires. I don't know how fast i got to, but I wasn't pushing it too much. I still had more to go, but, I didn't want to lose my job AND I don't my tires to shred. Most truck tires aren't exactly built for speed ratings-which scares me because my truck constantly wants to go fast on the interstate since it is a high gear rear and torquey engine. I wish I had my gps on it. But then again, my gps sometimes reads I walk 268 mph (it's a hiking handheld gps that sometimes briefly loses signal)
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my gps sometimes reads I walk 268 mph
Contact Willy Coyote.... you could help him get that roadrunner for once!
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I got mine upto about 100mph when I first got it road worthy, and it still had some left, probably not too much though. Since then It doesnt go over about 80mph. It'll do it, but I won't.. ;) I think when you hit 90+ the gas guage drops as fast as the odometer turns.
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I do 104 in the quarter. Don't know what top speed is yet.
Sent from my DROIDX using Tapatalk
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We got tapatalk now :o
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120 mph @ 6100 rpm
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120 mph @ 6100 rpm
ouch! can you say redline?
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We got tapatalk now :o
LOL, yeah it is here now.
When my 73 was running (454/muncie M22, 3.42 gears, 29" tall tires) I was running away from a 90 Mustang at 7800rpms before I ran out of 4 lane road no idea on how fast I was going, but he was not close.
Riding my by buddy in his 70 Camaro we dropped the driveshaft and pole vaulted the car at somewhere above 150+ (454/TH400, 7400rpms, 3.42 gears, 28" tires) Car was accurate at 120mph (2 miles a minute) luckily it landed on the wheels, but tore the whole drivers side exhaust off. It was one of those times when you see a flash of light, luckily it was reflection of the headlights on the pavement..
I have had my FRC Corvette up to 172mph, FZR600 140 something, let off when I cross the centerline and hit a marker and the bike left the ground.
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6100 is pretty safe for my motor, and actually pretty low for a race deal...
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My '94 Olds Bravada which has all wheel drive hit 110, I used to set my cruise in my '90 Beretta GT at 120, I took my '00 Grand Am GT up to 135 before the limiter stopped me, and when I was about 10 years old my moms boyfriend and I hit 145 in his Firebird Trans-Am with the T-tops off and then he told me not to tell me mother! I think its safe to mention now...
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and actually pretty low for a race deal...
I didn't want average person reading this and thinking thier stock set up should be cruising aroudn 6100. heck, throw a Rick Hendricks 358cid engine in there and tach her around 9800 for 500 miles, no biggie.
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I've hit 127 in my yukon xl! Lol when the tune was don't the 98mph limiter was moved to 135
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156 mph in a 97 Trans Am ran out of road, I know it would have hit 160, havent had the wifes 2000 WS6 over 120 yet, but it will get there in a heartbeat and supposedly will do 161. 145 in a 90 Mudstane GT, 140mph on a ninja 1000 many moons ago. Ill stick with four wheels at those speeds now.
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Well my truck, probably 70, but top speed on 4 wheels 215 in a Lamborghini ( not my car lol ), and on 2 wheels 195 on a souped up gsxr I used to own. (165 on my current fjr 1300 )
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Anything over 150 should have a roll cage or wings, lol
95 in the truck with 33's is plenty for me nowadays, and I've broken too many sleds, helmets, and ribs.
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I just picked up some 265/70/16s since my 75s were bald. Will the shorter tires increase my speed and lower my rpms, or lower my speed and increase my rpms? Like, will it lower my overall gear ratio or raise it?
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it will lower your top end and raise your take off.
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and your speedometer will be off.
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[/quote]and your speedometer will be off.
yep, I have 245/60 R15s on the front and 275/60 R15s on the rear, great in cornering and gives a good ride too.
my speedometer reads faster than I'm actually going and gets worse the faster I go. I had my wife follow me in the Monte so I know 35 on the speedo = about 27 in reality, on the highway it says I'm doing 100 when I'm only going about 80.
As for the take off and top speed, I haven't driven it with the stock tire size so I don't know if there is a difference, but I do know that my truck takes off fairly quick for a 305 and will hold 90 all day long on the highway, or till it runs out of gas...
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Well, my speedo, when it worked, always showed 5mph faster than I was actually going. So, will my accelaratio be faster but my top speed lower? Ive already noticed that my rpm-speed ration is different. Before, 2000rpms was 45mph. now 2000rpms is about 42, all according to my gps speedo. So I guess my gas mileage is going to go south now.
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So I guess my gas mileage is going to go south now.
that all depends on where you drive. Do a lot of interstate driving, yes. Do a lot of city driving, no.
I like a higher gear number (or equivalent to a smaller wheel/tire diameter) if I do a lot of city driving---quicker take off and you dont have to keep your foot in the accelerator, as compared to a tall gear (or larger diamter tire) and doing city driving where you'd have to keep your foot in the accelerator to get going.
Each stop light, and you have to accelerate so much more to get her going with a taller gear (smaller number).
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With only that much difference I don't see that big of a difference and for every 5mph it will be .09 MPH difference. Lets say you have 3.23 ratio you will have a 3.23 with the 65s
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and actually pretty low for a race deal...
I didn't want average person reading this and thinking thier stock set up should be cruising aroudn 6100. heck, throw a Rick Hendricks 358cid engine in there and tach her around 9800 for 500 miles, no biggie.
sorry, don't rev your engine this high if it is stock
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Okay, so explain this on, all might internet peoples. (: haha. So, yesterday, 2000rpm equalled 42mph. And today..... 2000rmp equalled 49mph..... Nothing has been changed, removed, added, etc. what would cause the difference?
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Is this with the tire change?
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eyeglasses dirty?
what kind of transmission do you have, manual or auto---if auto, lock up converter? Makes a difference.
If you have an auto without a lockup converter engaged, then the rpms will rise and decrease depending on your accelerator actions. If you are accelerating, your rpms could be higher but lower speed.
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This change in speed to rpm ratio is after the tire change. By that, I mean, after the tire change, one night with 265/70/16s 2000rpms equalled 42. And the next night with 265/70/16s 2000rpm equalled 49. Both of these speeds is measured by my gps speedometer.
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could be tread depth, air pressure. I ask again, what kind of trans?
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Sorry, its in the first post. Sm465 manual 4spd. Granny lown
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thinking maybe something to do with the speedo cable, gear or gauge. not sure, is it staying at 49mph @2k? or did it go back down maybe clutch slipping???
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I topped my 79 out at about 125-130 on the I10 a few years ago, she was redlined and I was scared but it was jolly good fun.