The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 08-21-2010, 08:17 AM   #26
Hazieview
Building Dreams out of Dimes!
 
Join Date: May 2005
Location: Bonham, Tx
Posts: 892
Re: What is your top speed? Post your MPH and Setup!

I love all the responces!

The main reason I asked this question is because I kind of thought one more thing was unusual...

Why would you need a 160mph Speedometer and a 10,000rpm tach in a square body? I would understand if you had a blower or raced all the time but with my sb400 I can't turn more than 6000 rpms without banging it out. I have .308 gears and a 350th trani so hitting 160mph isn't very likely to say the least.

I'm thinking 120mph max speedometer and a 8,000 rpm max would be just fine. I say 8,000 because it is hard to find a 7000rpm in 5" for a good price.

Thanks for the replies guys! Can anybody run 160mph and 10000rpms? That something I would love to see!
Hazieview is offline   Reply With Quote
Old 08-21-2010, 08:10 PM   #27
gchemist
BAD BOW-Silverado XST
 
gchemist's Avatar
 
Join Date: May 2000
Location: Senior Member from Austin, TX
Posts: 6,431
Re: What is your top speed? Post your MPH and Setup!

3100 RPMs, 700R4, 3.08 gears, 27" tire = 115.5 MPH. The ZZ4 still has power. I'm curious if it can hit 3400-3800 RPMs (126-134 MPH) I'm still scared of taking it over 3100 RPMs. I need a salt flat or track. A few more mods and I'll push it more.
__________________
Gerardo a.k.a. Mad Chemist
Silverado XST videos

Last edited by gchemist; 08-22-2010 at 12:19 AM.
gchemist is offline   Reply With Quote
Old 08-21-2010, 09:14 PM   #28
3r!c84
Badass
 
3r!c84's Avatar
 
Join Date: Jan 2009
Location: lox. fl
Posts: 4,586
Re: What is your top speed? Post your MPH and Setup!

Quote:
Originally Posted by Hazieview View Post
I love all the responces!

The main reason I asked this question is because I kind of thought one more thing was unusual...

Why would you need a 160mph Speedometer and a 10,000rpm tach in a square body? I would understand if you had a blower or raced all the time but with my sb400 I can't turn more than 6000 rpms without banging it out. I have .308 gears and a 350th trani so hitting 160mph isn't very likely to say the least.

I'm thinking 120mph max speedometer and a 8,000 rpm max would be just fine. I say 8,000 because it is hard to find a 7000rpm in 5" for a good price.

Thanks for the replies guys! Can anybody run 160mph and
10000rpms? That something I would love to see!

pm me with more info on your 400sbc
__________________
Think outside the box?
-84c10 (1stcar)→My Build
-00 Saturn 5spd

drop a gear and disappear!

1/4:13:90
3r!c84 is offline   Reply With Quote
Old 08-21-2010, 10:05 PM   #29
piecesparts
Parts and more parts
 
piecesparts's Avatar
 
Join Date: Nov 2003
Location: Lebo, Kansas (middle of nowhere
Posts: 6,821
Re: What is your top speed? Post your MPH and Setup!

I have a 700 R4 tranny, 3.73 gears, 383 stroker engine, 28" rear tires and I run at 70 MPH at 2500 RPMs. I can run clear off of the speedo at 2800 to 2900 RPMs. I have no need to run 3100 RPMs and really do not desire to.
__________________
Frank
piecesparts is offline   Reply With Quote
Old 08-21-2010, 11:24 PM   #30
1985-GMC
Chevy Enthusiast
 
1985-GMC's Avatar
 
Join Date: Jul 2009
Location: Canyon Lake Texas
Posts: 2,024
Re: What is your top speed? Post your MPH and Setup!

I got about where the 95 mark would be in my old dually with 4.10 gears, and 31" tires but without a tach I didn't want to push it much farther, and the speedo read about 5 under to begin with. It was a mild built 454 and it would get there pretty quick especially when I would take off in 3rd and only shift once at 55 to 4th.
__________________
Tony
1985 GMC K2500 restoration Project: Rust, White & Blue
1989 Chevy R3500 CC Cummins & 4X4 swap some day...
1989 Burb (D60, 14BFF, 12V, NV4500, NP205, 37" tires in progress)
1985-GMC is offline   Reply With Quote
Old 08-22-2010, 05:20 AM   #31
GmtGmt
Conversion Truck Addicted
 
GmtGmt's Avatar
 
Join Date: Sep 2009
Location: Denmark, Europe
Posts: 1,551
Re: What is your top speed? Post your MPH and Setup!

anyone know what top speed would be on with a N/A 6.2 Diesel 4 Speed no overdrive with 4.10 gears and 235/85/16 wheels its a crew cab big dooley
__________________
Thomas

Quote:
Tonight mine pulled a few cars out of snowbanks, and is sitting in my driveway, icicles on the grille, wheels just white cakes of snow, buried up to the lug nuts in powder, straps and chains wrapped around the bumpers, the outline of the wipers clear in 4 inches of snow on the windshield... A tired warrior of the 1980s in a world of low profile tires, front wheel drive, and plastic bumpers, where people stay in their houses until snowplows move the offending substance from their paths, too helpless to travel without AAA and chains and salt, clearing their windows with longhandled brushes while gently stepping around in the snow trying to stay nice and dry.
GmtGmt is offline   Reply With Quote
Old 08-22-2010, 11:04 AM   #32
GMC91
Always trouble
 
GMC91's Avatar
 
Join Date: Jul 2009
Location: Hartsellle, Al
Posts: 1,111
Re: What is your top speed? Post your MPH and Setup!

I had a 100MPH speedo in my 76 and it was circling back around and hit 10. So I really have no clue exactly how fast, but I was passing interstate ppl like they were in reverse. SBC350 .040 over with a built TH350 and 3.08 rear end.
__________________
91 Silverado Regular cab, 2wd, swb-project truck
97 Silverado Extended cab, 2wd, swb-driver
GMC91 is offline   Reply With Quote
Old 08-22-2010, 11:21 AM   #33
hotrod_991
Registered User
 
hotrod_991's Avatar
 
Join Date: Jul 2009
Location: Thibodaux, LA
Posts: 479
Re: What is your top speed? Post your MPH and Setup!

fastest I have had my 77 long bed was when if first got it from my dad and it still have the old 305 punched 60 over with a cam. TH350 and unknown gears. was abotu 110 i took the pic at 100 then gave her alil more and slowed down.
Attached Images
 
__________________
"Buckle up I wanna try somethin!!"

"of course it will hold!, I welded it!"

1977 c10 under knife for full rebuild, 5.3l 4l60e drive rain swap, replacement frame and green repaint
hotrod_991 is offline   Reply With Quote
Old 08-22-2010, 01:12 PM   #34
moneyeater
Registered User
 
moneyeater's Avatar
 
Join Date: Feb 2003
Location: Northern Germany,near Bremen
Posts: 684
Re: What is your top speed? Post your MPH and Setup!

When i had my baby on the dyno it made 243.2 hp at the wheels and 218 km/h wich would be 135 mph!
the dyno is not representative for real streetaction and driving over 100 mph requires a second pair of pants but i think 120 would be possible on the autobahn!
I have a worn out 1968 carter 625 cfm carb, a stock th 350 and 3.08 gears.
Volker
__________________
My little US vehicle parts business:
http://www.thegearheaddepot.com/
Come have a look!

´81 GMC C 10, Spanish Red
moneyeater is offline   Reply With Quote
Old 08-22-2010, 04:03 PM   #35
willett
Another Day, Another Dollar
 
willett's Avatar
 
Join Date: Nov 2008
Location: North Vancouver, BC
Posts: 1,316
Re: What is your top speed? Post your MPH and Setup!

i got my '78 up to 85 or 90 once. (140 km/h). 454, turbo 400 and 3.73 on 35" mud terrains.

the hood started to shake and for a brief moment it felt like the truck was hovering off of the ground.


forgot to mention.
650 cfm eddelbrock 4 barrel carb
__________________
-78 K20 Cheyenne 454 long box, 4" lift, 35" MT's, '84 cab, '80 box

"its hip to be square"

Last edited by willett; 08-22-2010 at 04:04 PM.
willett is offline   Reply With Quote
Old 08-22-2010, 07:05 PM   #36
von guido
Registered User
 
von guido's Avatar
 
Join Date: Sep 2009
Location: outside atlanta
Posts: 156
Re: What is your top speed? Post your MPH and Setup!

Quote:
Originally Posted by Hazieview View Post
I love all the responces!

The main reason I asked this question is because I kind of thought one more thing was unusual...

Why would you need a 160mph Speedometer and a 10,000rpm tach in a square body? I would understand if you had a blower or raced all the time but with my sb400 I can't turn more than 6000 rpms without banging it out. I have .308 gears and a 350th trani so hitting 160mph isn't very likely to say the least.

I'm thinking 120mph max speedometer and a 8,000 rpm max would be just fine. I say 8,000 because it is hard to find a 7000rpm in 5" for a good price.

Thanks for the replies guys! Can anybody run 160mph and 10000rpms? That something I would love to see!
there are reasons tachs go up that high. my old super gas camaro had a 6000rpm stall and the 7al limiter was at 9000rpm.
von guido is offline   Reply With Quote
Old 08-22-2010, 08:06 PM   #37
78 Chevyrado
Account Suspended
 
Join Date: Dec 2007
Location: Unnapreciative, Trollville
Posts: 2,079
Re: What is your top speed? Post your MPH and Setup!

Quote:
Originally Posted by Hazieview View Post
I love all the responces!

The main reason I asked this question is because I kind of thought one more thing was unusual...

Why would you need a 160mph Speedometer and a 10,000rpm tach in a square body? I would understand if you had a blower or raced all the time but with my sb400 I can't turn more than 6000 rpms without banging it out. I have .308 gears and a 350th trani so hitting 160mph isn't very likely to say the least.

I'm thinking 120mph max speedometer and a 8,000 rpm max would be just fine. I say 8,000 because it is hard to find a 7000rpm in 5" for a good price.

Thanks for the replies guys! Can anybody run 160mph and 10000rpms? That something I would love to see!

Most of them are for show. It's like in my 87 1/2 ton while I never went over 80MPH, I hated that 85MPH speedo and wished I had the 100MPH one like I do in my 78.

While they do have a purpose and there are vehicles that would use the entire range, it's extremely limited and are for show on most cars.

I never saw a street car of any kind run 9,000 RPM or even 8 for that matter. Even the 8k tach is overkill in 90% or more cars. Most v8s dont go over 4500RPM, and even the bad motor scooters usually top out around 6500RPM. Seems the most common warmed over engines redline at around 5500RPM.


If I could find one, I'd love to have a 5k tach as I have an 8k tach and never been over 4500RPM in my truck, that's just all that's available in small tachs.


My focus has a 7k tach and its green all the way to 7k RPMS, but it has a 140MPH speedo and the cars governor cuts off at 105.
78 Chevyrado is offline   Reply With Quote
Old 08-22-2010, 10:31 PM   #38
camshaftgsxr
Registered User
 
camshaftgsxr's Avatar
 
Join Date: Feb 2010
Location: Asheville, N.C.
Posts: 785
Re: What is your top speed? Post your MPH and Setup!

Top speed for mine is 120ish beside a Mercedes (speed checker) is was pushing it she's a real beast to handle above 75.

Quick question, with 3.42 gears and a 700r4 what rpm should I see at 65 mph I can't figure out the math please pm the links to me as not to clutter this thread up
__________________
camshaftgsxr is offline   Reply With Quote
Old 08-23-2010, 12:32 AM   #39
gchemist
BAD BOW-Silverado XST
 
gchemist's Avatar
 
Join Date: May 2000
Location: Senior Member from Austin, TX
Posts: 6,431
Re: What is your top speed? Post your MPH and Setup!

If you are running a 28" tire, then 1900 RPMs = 65.5 MPH.
If the engine speed (for this example) RPM = 6000 revolutions/minute, then the driveshaft speed is the engine speed divided by tranny gear ratio R1 = ( 6000 / R1) revolutions/minute,and the rear axle speed is the driveshaft speed divided by rear-end ratio R2 = ( 6000 / (R1*R2) ) revolutions per minute. (Note: the symbol * indicates multiplication, and / indicates division)

So, the rear tire will be making 6000 / (R1*R2) revolutions each minute, causing the car to move forward (2*pi*r) * ( 6000 / (R1*R2) ) inches/minute (where r is the loaded tire radius in inches, and 2*pi = 6.28).

That is, the car will be moving ( 6000 * 6.28 * r) / (R1*R2) inches per minute.

Since 1 mile = 5280 feet = 63,360 inches, and 1 hour = 60 minutes, then the conversion from inches per minute to miles per hour is ( 60 / 63,360 ).

So, if the engine is turning 6000 rev/min then the car must be going (60 / 63,360) * ( ( 6000 * 6.28 * r) / (R1*R2) miles/hour.

Rewriting that all into a tidy form:

(0.00595) * (RPM * r) / (R1 * R2) = vehicle speed in miles/hour

where:
RPM = engine speed, in revolutions/minute
r = loaded tire radius (wheel center to pavement), in inches
R1 = transmission gear ratio
R2 = rear axle ratio

Get it? Okay use this http://wahiduddin.net/calc/calc_speed_rpm.htm
__________________
Gerardo a.k.a. Mad Chemist
Silverado XST videos

Last edited by gchemist; 08-23-2010 at 12:36 AM.
gchemist is offline   Reply With Quote
Old 08-23-2010, 07:36 AM   #40
big10ratrod77
Registered User
 
big10ratrod77's Avatar
 
Join Date: Aug 2009
Location: hillborough nc
Posts: 410
Re: What is your top speed? Post your MPH and Setup!

well its a stock 77 big 10 350/sm465/3.73 and 28's and ive had it wound past 100 pointing stright down and i figure like 130 as a guess? if i had a t5 five speed and a looooong enough strech of road i could crack 160... it would be tearably scary couse i might start loseing metal or somthing but yea it would do it if i could keep it between the ditches lol
__________________
77 chevy BIG 10 350/sm465/12bolt w 3.73 bout 240 horse power NO power steerin
79 chevy 1/2 ton 250/three on the tree/3.08s soon to get built 250/floor shift conversion/3.08s
81 mercedes 300d 25 MPG
77 chevy BIG DOOLEY 454/sm-465/14 bolt 4.10s "fully loaded"
73 plymouth duster 225 slant six/230 3 speed/8 1/4 trying to acheve 300 horse six http://www.cardomain.com/ride/3135091
'77 chevy trucks. built to stay tough.
life is short build a hot rod
big10ratrod77 is offline   Reply With Quote
Old 08-23-2010, 10:15 AM   #41
team39763
Registered User
 
Join Date: Feb 2007
Location: Texas
Posts: 469
Re: What is your top speed? Post your MPH and Setup!

Quote:
Originally Posted by jrcaprai View Post
What Cam, Rear end Gears, Tire Size, are you running? long bed, or Short bed?
It's was a 226/228 EFI cam from Nelson Performance. 4.56 gears, 28X10.5 slicks, and it's a shortbed. It was a slug out of the hole but ran good on the top end.
__________________
1982 Silverado - SBE, cleaned up GM heads, small cam, TH350, 850 Demon, 4.56 gears, and caltracs.
Best time so far 11.8@XXXMPH
team39763 is offline   Reply With Quote
Old 08-23-2010, 03:12 PM   #42
Matt Man
Registered User
 
Matt Man's Avatar
 
Join Date: Oct 2009
Location: Buhl, Idaho
Posts: 1,438
Re: What is your top speed? Post your MPH and Setup!

chevy c30 454/400 3:73 had it up to about 90 have no need to speed really... the motor was screamin.
__________________
86 c30 crew cab dually 454/400 4/6 drop SOLD 1-8-11
1981 chevy K10 short Bed Scottsdale SOLD 10-26-2020
67 GMC Stepside Straight six/3 on the tree "The Peach"
2020 Silverado Double Cab LT Z71 5.3 8 speed Daily Driver

K10 build http://67-72chevytrucks.com/vboard/s...d.php?t=671934

The Peach build http://67-72chevytrucks.com/vboard/s...d.php?t=733903



Matt Man is offline   Reply With Quote
Old 08-23-2010, 06:47 PM   #43
78GMC SIERRA CLASSIC
Registered User
 
Join Date: Apr 2010
Location: Canada EH?
Posts: 37
Re: What is your top speed? Post your MPH and Setup!

I don't hit stop speed cause im a good driver
78GMC SIERRA CLASSIC is offline   Reply With Quote
Old 03-23-2013, 03:00 PM   #44
silversnail86
Registered User
 
silversnail86's Avatar
 
Join Date: Jan 2012
Location: livingston mt
Posts: 54
Re: What is your top speed? Post your MPH and Setup!

I know this thread is a few years old, but seein' as I just pulled 126 M.P.H. in my 86' I had to put it somewhere.
It's 364 cu. in. 10.5:1, 416 heads ported(305 h.o. heads), comp XE268 cam. Oh and T-5 and 28 in tires. 4th gear and 4150 rpms, it has a little more but I was getting close to my exit. And I gotta say, to those of you afraid to go over 100 in your truck, that's just sad.
silversnail86 is offline   Reply With Quote
Old 03-23-2013, 03:56 PM   #45
l1l
Registered User
 
Join Date: Jun 2011
Location: FL
Posts: 247
Re: What is your top speed? Post your MPH and Setup!

well , I was looking through all the responds and guess what, no one had ever push his engine to the limit, check the following video out, its big block 454 long bed step side killing a porsche at almost 200 miles.

tell me what you think, and excuse the music

http://youtu.be/prAydy9W0Xc
l1l is offline   Reply With Quote
Old 03-23-2013, 04:03 PM   #46
silversnail86
Registered User
 
silversnail86's Avatar
 
Join Date: Jan 2012
Location: livingston mt
Posts: 54
Re: What is your top speed? Post your MPH and Setup!

That's kmh not mph so it's only 160 mph, still impressive though.
__________________
86 C10 LWB 364 cu.in. ported 416 heads, 10.5:1, Comp XE268 cam, T-5.
silversnail86 is offline   Reply With Quote
Old 03-23-2013, 04:35 PM   #47
INSIDIOUS '86
Registered User
 
INSIDIOUS '86's Avatar
 
Join Date: Jul 2009
Location: washington
Posts: 4,178
Re: What is your top speed? Post your MPH and Setup!

Out mine to 135mph in a deserted hwy. had 308 gears and the wind stopped it cold at 130 and I had 1000rpm left of power and this was before beeing lowered. Looking forward to trying again with the 373s and after I've dropped it
Posted via Mobile Device
__________________
377 sbc thumpr cam autogear m23 muncie 3:73 Detroit trutrac
3''spintech prostreet mufflers xpipe 1 3/4 headers
build thread !http://67-72chevytrucks.com/vboard/s...d.php?t=577217
Iroc gauge threadhttp://67-72chevytrucks.com/vboard/s...d.php?t=554511
INSIDIOUS '86 is offline   Reply With Quote
Old 03-23-2013, 10:07 PM   #48
78maliburat
Registered User
 
Join Date: Jul 2009
Location: cleburne texas
Posts: 174
Re: What is your top speed? Post your MPH and Setup!

45 mph tops


78maliburat is offline   Reply With Quote
Old 03-24-2013, 12:35 AM   #49
PAWS 72
Registered User
 
PAWS 72's Avatar
 
Join Date: Nov 2011
Location: Sheffield, ALA
Posts: 2,471
Re: What is your top speed? Post your MPH and Setup!

With the 400 that we had in the 72 back around 1988 the father in law floated the valves at 115.State trooper friend was behind us.
PAWS 72 is offline   Reply With Quote
Old 03-24-2013, 01:46 PM   #50
meatwagon83
Registered User
 
meatwagon83's Avatar
 
Join Date: Dec 2012
Location: Preble county ohio
Posts: 1,914
Re: What is your top speed? Post your MPH and Setup!

i've had my needle pointing straight down quite a few times, not sure how fast that is, 83 crew cab dually 454 thumper cam, holly 770sa, air gap rpm, roller rockers, headers and a stock bottom end, th400 3.73 rear gears, 30 inch tall tires
__________________
"DON'T TOUCH THE TRIM!!"-Early Kyler
meatwagon83 is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:32 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com