Higher speedometers... - The 1947 - Present Chevrolet & GMC Truck Message Board Network

ThatOneBlue67 · 01-26-2007, 12:24 AM

Hi (again)!

I'm assuming that with the 350 V8 and a good transmission, I can top over 100. Does anyone know of a speedometer (which reads 120 or over) that I could find in another car (no aftermarket speedos). Preferrably a gauge that looks very similar to the truck's.

I've read that some people use a 2nd gen. Camaro speedometer. Are there any modifications required or does it bolt right up to the cluster housing?

Thanks for your help, guys.

matthufham · 01-26-2007, 02:44 PM

with my 350, th350, and 3.73 gears, i havent hit 90

jimmydean · 01-26-2007, 03:29 PM

Mine does about 75, but it feels like 120!

bobthecop · 01-26-2007, 03:35 PM

Where can you go that fast.....legally?????

68 50th · 01-26-2007, 03:57 PM

I have had decals made to convert the speedo lens to kilometers per hour (KPH) in 0-160 and 0-200 range.
You can cut the "KPH" out but there will be some gearing to do to make the speedo show correct MPH speed.
I still have some of these, let me know if you are interested.

JAKES 68GMC · 01-26-2007, 05:27 PM

Just leave your speedo the way it is, that way, if you bury the needle at 100, you can brag because you buried the needle. I don't see why you'd want to drive 100mph though, unless you were at dragstrip or an old airport where it would be safe to do so.

Longhorn Man · 01-26-2007, 05:38 PM

I can hit 100 with 4.10 gears and 29 or so inch tall rear tires... pretty much any truck with a stock healthy motor can hit the century mark.

3.07's with 28 inch tall tires (was at 100 but had to lift total bummer) I had this one held at the M on MPH for about 10 or 15 miles one time.... talk about an adrenilin rush!

Here's the 4.10 truck with 29 or 30 inch tall tires... I can't remember where the tach needle was... I think it was just north of 4000

FarmTruk · 01-26-2007, 05:41 PM

LHM...I hope that's yer passenger taking those pics...

70rs/ss · 01-26-2007, 05:57 PM

I think the speedo is reading 100, but with 4:11's that'll make a speedo read fast (unless it was a truck set up with 4:11's from the factory?) To clarify, if you have a truck with a 3:08 and you bolt in a 4:11, the speedo will read faster than actual speed. If that is a 4:11 equipted truck with the correct gear in the transmission for the 4:11 rear, then 100mph must have been loud and high RPM!!

Longhorn Man · 01-26-2007, 06:09 PM

the 3.07 truck, came with 3.07 gears.
The 4.10 truck, came with 4.10 gears.
These are not the same truck. The red dash truck is the old GMC, the gold dash truck is the longhorn.
I took the photos myself, but it was just a point and click, not holding the camera to my face... Took about 5 shots each... these are the ones that came out.

see ten · 01-26-2007, 06:41 PM

A crappy shot but you get the point!

*rage'nrat638* · 01-26-2007, 08:24 PM

O MY...look out for that deer

JAKES 68GMC · 01-26-2007, 09:44 PM

71Chevy4-speed · 01-26-2007, 09:50 PM

Well my 71.

4.56's
235/85/16 basically a 31" tire
4 speed

5931 rpm is 120mph and I seen 6000 lol.

FarmTruk · 01-26-2007, 10:52 PM

I...CAN'T DRIVE...55

CPNEJR · 01-26-2007, 11:47 PM

hmmmmmmm i wonder if i could bury the needle with my setup? i got 350 3 on the tree and 3.08's i guess i'll just have to wait to get my license and my truck together to find out

**PICKMUP** · 01-26-2007, 11:56 PM

Here's one...130mph & 7K tach---Camaro
I also have a '70 LT1 Camaro 150 speedo & 8K tach-(not the car-just the gauges)

smoked68 · 01-27-2007, 12:22 AM

Ive buried the needle for a couple sec in mine a few times. Mine was a factory equipped 4.11 but back then it had a th350 in it. havent done it since the muncies been in it.

Longhorn Man · 01-27-2007, 07:31 AM

CPNEJR, your 3.07 gear will rev just like my 3.07 truck... the top photo. Tranny doesn't matter, both have a one to one final ratio. Yours would actually be a littlelower due to no slippage.

GREASEMONKEY72 · 01-27-2007, 11:54 AM

ive been wanting to peg out my truck for a while but no place to really do it the fastest ive been in to so far is 90mph but now that i put in new valve seals and it has freed up some power maybe i can get out somewhere and let her fly

Mrboson1 · 01-27-2007, 02:08 PM

Sounds like a bunch of fun, be safe!

speedracer · 01-27-2007, 06:55 PM

Ive had mine go around back to zero, at about twenty on the second trip around it starts to bounce alot(I figure thats about 100-110 real mph). I'm putting an autometer 160 in its place but I need to find the right gear for the tranny to get it right.

68Stepbed · 01-27-2007, 07:01 PM

My stock 350/TH350/3.73 combo with 28" tires I could hit 100 at about 4800 rpm. By that time I usually ran out of road and had to lift it. If you have 3.42 or 3.07 gears and a correct speedo, you could go alot faster.

49studebaker · 01-27-2007, 11:12 PM

Oh ya, It's basically possible to do it in anything you guys are driving. I don't reccomend it but I will admit....last year heading down I-80, middle of nowhere in Nevada, a ricer with a wing/ground effects, etc,etc, started to pass me. The 49 Stude likes to run around 80 on the interstate so he was going about 90, couldn't let that happen.So with a 350ci, 3:50 rearend, turbo 350, we basically walked away from him. My wife didn't even look that worried. I'm sure my 71, once finished will handle way better.

ThatOneBlue67 · 01-28-2007, 11:02 PM

I go out and set my own land speed records out on the county roads. It's kinda scary when the road is only 2+ cars wide. I keep telling myself I'll put in a 4 speed or something, just so I can go a little faster. My buddy and I hit 130 in his Z28. Yeah, its stupid. But we're still setting the goal at 150 (but possibly somewhere safer like the drag strip). Oh well, just curious.

01-26-2007, 12:24 AM	#1
ThatOneBlue67 I survived Dead Man's Curve. Join Date: Apr 2006 Location: The Nine-Five-687 Posts: 389	Higher speedometers... Hi (again)! I'm assuming that with the 350 V8 and a good transmission, I can top over 100. Does anyone know of a speedometer (which reads 120 or over) that I could find in another car (no aftermarket speedos). Preferrably a gauge that looks very similar to the truck's. I've read that some people use a 2nd gen. Camaro speedometer. Are there any modifications required or does it bolt right up to the cluster housing? Thanks for your help, guys. __________________ "The people should not be afraid of their government. The government should be afraid of it's people." "The Hurricane" 1967 Chevrolet C10 350 Eight Cylinder, 700R4 BowtieOverdrive *Cherry Bomb...* Disturbing the Peace Since 1968.

01-26-2007, 02:44 PM	#2
matthufham Registered User Join Date: Feb 2005 Location: Carl Junction, Missouri Posts: 2,061	Re: Higher speedometers... with my 350, th350, and 3.73 gears, i havent hit 90

01-26-2007, 03:29 PM	#3
jimmydean Registered User Join Date: May 2005 Location: Beaverton, OR Posts: 3,728	Re: Higher speedometers... Mine does about 75, but it feels like 120!

01-26-2007, 03:35 PM	#4
bobthecop Senior Member Join Date: Nov 2006 Location: Yukon Oklahoma Posts: 2,647	Re: Higher speedometers... Where can you go that fast.....legally????? __________________ Happiness is towing your "new" truck home. 1972 C-10 1982 GMC (parts truck??) 1969 c10 parts truck 1969 C-10 ( my sons) 1992 Silverado 4X4 (now the boys truck)(now mine again) 2002 Tarus (my wife loves that car)

01-26-2007, 03:57 PM	#5
68 50th Senior Member Join Date: Jul 2004 Location: Sweden Posts: 833	Re: Higher speedometers... I have had decals made to convert the speedo lens to kilometers per hour (KPH) in 0-160 and 0-200 range. You can cut the "KPH" out but there will be some gearing to do to make the speedo show correct MPH speed. I still have some of these, let me know if you are interested. Attached Images __________________ Mats.. ---------------------------------------------------- 1971 Cheyenne Super Custom Camper 475CBB/TH400/AC 1992 Silverado Sport Truck 1988 Silverado 2500 Ext Longbed 4x4 2001 GMC Sierra SLT 4x4 1990 Chevrolet K3500 1965 Pontiac Grand Prix 1980 Z 28 350/4-speed/AC/T-top 1980 Camaro Coupe V6/3-speed 1979 Buick Century Wagon

01-26-2007, 05:27 PM	#6
JAKES 68GMC Aluminum slot wheels rule... Join Date: Jan 2006 Location: Maine Posts: 6,211	Re: Higher speedometers... Just leave your speedo the way it is, that way, if you bury the needle at 100, you can brag because you buried the needle. I don't see why you'd want to drive 100mph though, unless you were at dragstrip or an old airport where it would be safe to do so.

01-26-2007, 05:38 PM	#7
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	Re: Higher speedometers... I can hit 100 with 4.10 gears and 29 or so inch tall rear tires... pretty much any truck with a stock healthy motor can hit the century mark. 3.07's with 28 inch tall tires (was at 100 but had to lift total bummer) I had this one held at the M on MPH for about 10 or 15 miles one time.... talk about an adrenilin rush! Here's the 4.10 truck with 29 or 30 inch tall tires... I can't remember where the tach needle was... I think it was just north of 4000 Last edited by Longhorn Man; 01-26-2007 at 05:39 PM.

01-26-2007, 05:41 PM	#8
FarmTruk In Memoriam... Join Date: Nov 2006 Location: Wallburg, NC Posts: 1,216	Re: Higher speedometers... LHM...I hope that's yer passenger taking those pics... __________________ '68 C10 SWB 307ci 2BBL *FarmTruk Pics Here* *"You know, doing what is right is easy. The problem is knowing what is right."*

01-26-2007, 05:57 PM	#9
70rs/ss Registered User Join Date: Dec 2004 Location: Northern AZ Posts: 7,270	Re: Higher speedometers... I think the speedo is reading 100, but with 4:11's that'll make a speedo read fast (unless it was a truck set up with 4:11's from the factory?) To clarify, if you have a truck with a 3:08 and you bolt in a 4:11, the speedo will read faster than actual speed. If that is a 4:11 equipted truck with the correct gear in the transmission for the 4:11 rear, then 100mph must have been loud and high RPM!! Last edited by 70rs/ss; 01-26-2007 at 05:57 PM.

01-26-2007, 06:09 PM	#10
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	Re: Higher speedometers... the 3.07 truck, came with 3.07 gears. The 4.10 truck, came with 4.10 gears. These are not the same truck. The red dash truck is the old GMC, the gold dash truck is the longhorn. I took the photos myself, but it was just a point and click, not holding the camera to my face... Took about 5 shots each... these are the ones that came out.

01-26-2007, 06:41 PM	#11
see ten WTB this ad Join Date: Sep 2004 Location: Lafayette Georgia Posts: 5,074	Re: Higher speedometers... A crappy shot but you get the point!

01-26-2007, 08:24 PM	#12
rage'nrat638 Account Suspended Join Date: Mar 2003 Location: THE FALL GUY CHICAGO IL Posts: 5,883	Re: Higher speedometers... O MY...look out for that deer

01-26-2007, 09:44 PM	#13
JAKES 68GMC Aluminum slot wheels rule... Join Date: Jan 2006 Location: Maine Posts: 6,211	Re: Higher speedometers...

01-26-2007, 09:50 PM	#14
71Chevy4-speed Speed Limit = Floorboard Join Date: Jan 2004 Location: Kasilof, Alaska Posts: 803	Re: Higher speedometers... Well my 71. 4.56's 235/85/16 basically a 31" tire 4 speed 5931 rpm is 120mph and I seen 6000 lol. __________________ 1971 C20 350, 4-speed - Sold. 1985 K10 350, Built 700r4, Edel 1406, Performer intake, MSD Ign, Hooker Comps, Silverstars, Piaa drivers, LED tails, Toyo A/T 31's, Eaton Posi, the project. "Build for torque, horsepower will follow"

01-26-2007, 10:52 PM	#15
FarmTruk In Memoriam... Join Date: Nov 2006 Location: Wallburg, NC Posts: 1,216	Re: Higher speedometers... I...CAN'T DRIVE...55 __________________ '68 C10 SWB 307ci 2BBL *FarmTruk Pics Here* *"You know, doing what is right is easy. The problem is knowing what is right."*



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01-26-2007, 11:47 PM	#16
CPNEJR Registered User Join Date: Sep 2003 Location: Franconia,N.H. Posts: 1,029	Re: Higher speedometers... hmmmmmmm i wonder if i could bury the needle with my setup? i got 350 3 on the tree and 3.08's i guess i'll just have to wait to get my license and my truck together to find out __________________ (Only) Member of the CPNE Fan Club Aint that the truth 67 C-10 350 with 3-speed tranny and 308 gears swb step 82 Z28 Camaro 355 small block over 350 hp and a borg warner super t-10 (blown engine) 72 Chevy K20 Suburban (future project) 70 Chevy K20 now 68 GMC K2500 2003 Chevy 2500hd ccsb 4X4 (daily driver)

01-26-2007, 11:56 PM	#17
PICKMUP "Trucks with Class" Join Date: Jul 2000 Location: OLYMPIA, WA, USA Posts: 8,159	Re: Higher speedometers... Here's one...130mph & 7K tach---Camaro I also have a '70 LT1 Camaro 150 speedo & 8K tach-(not the car-just the gauges) Attached Images

01-27-2007, 12:22 AM	#18
smoked68 Registered User Join Date: Oct 2006 Location: Rock Hill, SC Posts: 421	Re: Higher speedometers... Ive buried the needle for a couple sec in mine a few times. Mine was a factory equipped 4.11 but back then it had a th350 in it. havent done it since the muncies been in it. __________________ 1968 chevy shortbed, Dark Shadow Gray 4 bolt 383 Stroker,Weiand Super Charger, disc brakes, 9 inch, 391 gear, 20" Eagle wheels, muncie 4 speed/ Hurst shifter, 4/7 drop, Hedman midlengths, 3 inch exhaust w/ 2 chamber flows. 1966 Mustang with 306 roller, c-4, 9 inch Detroit locker rear. 1965 Fastback Mustang w/347 stroker, top loader 4spd, 9 inch detroit locker. 1966 Mustang coup, 306 roller, c4, 9 inch. 65 Cobra, 427, T6oo, 9inch, of course. First gen Hayabusa, airbox mod and running 2 exhaust cams.. Zoom Zoom Zoom

01-27-2007, 07:31 AM	#19
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,690	Re: Higher speedometers... CPNEJR, your 3.07 gear will rev just like my 3.07 truck... the top photo. Tranny doesn't matter, both have a one to one final ratio. Yours would actually be a littlelower due to no slippage.

01-27-2007, 11:54 AM	#20
GREASEMONKEY72 Registered User Join Date: Aug 2006 Location: Bakersfield,CA Posts: 7,893	Re: Higher speedometers... ive been wanting to peg out my truck for a while but no place to really do it the fastest ive been in to so far is 90mph but now that i put in new valve seals and it has freed up some power maybe i can get out somewhere and let her fly __________________ -steven Alte Seele S.S. "Allison" '72 C/10 LWB 350SB/TH350 - DD PITBULL IS NOT A CRIME

01-27-2007, 02:08 PM	#21
Mrboson1 Chevy 400 Join Date: Mar 2006 Location: Dallas, Texas Posts: 142	Re: Higher speedometers... Sounds like a bunch of fun, be safe! __________________ 68 Chevy C-10 pickup

01-27-2007, 06:55 PM	#22
speedracer Blank Join Date: May 2005 Location: Southington, CT Posts: 221	Re: Higher speedometers... Ive had mine go around back to zero, at about twenty on the second trip around it starts to bounce alot(I figure thats about 100-110 real mph). I'm putting an autometer 160 in its place but I need to find the right gear for the tranny to get it right. __________________ 1969 lwb 4/6 drop 17x8-18x10 torque thrust II's 327-420hp 2004R 3.73 posi. 1977 Corvette 350-375hp 4speed, silver show car. 2002 S10 xtreme, work truck 2004.5 VW jetta GLI 1.8T 6speed, weekend warrior. 2013 Audi A3 TDI, the wife's car

01-27-2007, 07:01 PM	#23
68Stepbed Registered User Join Date: Mar 2005 Location: 10-Uh-See Posts: 5,609	Re: Higher speedometers... My stock 350/TH350/3.73 combo with 28" tires I could hit 100 at about 4800 rpm. By that time I usually ran out of road and had to lift it. If you have 3.42 or 3.07 gears and a correct speedo, you could go alot faster. __________________ Matt 68 C10 stepside, LS1/700R4, TCI Engineering suspension system

01-27-2007, 11:12 PM	#24
49studebaker Senior Member Join Date: Nov 2005 Location: Victor, Montana Posts: 386	Re: Higher speedometers... Oh ya, It's basically possible to do it in anything you guys are driving. I don't reccomend it but I will admit....last year heading down I-80, middle of nowhere in Nevada, a ricer with a wing/ground effects, etc,etc, started to pass me. The 49 Stude likes to run around 80 on the interstate so he was going about 90, couldn't let that happen.So with a 350ci, 3:50 rearend, turbo 350, we basically walked away from him. My wife didn't even look that worried. I'm sure my 71, once finished will handle way better. __________________ 04 4x4 GMC Ext. Cab lifted 71 2wd GMC / Ramjet 350 ready for sheet metal 49 Studebaker pickup

01-28-2007, 11:02 PM	#25
ThatOneBlue67 I survived Dead Man's Curve. Join Date: Apr 2006 Location: The Nine-Five-687 Posts: 389	Re: Higher speedometers... I go out and set my own land speed records out on the county roads. It's kinda scary when the road is only 2+ cars wide. I keep telling myself I'll put in a 4 speed or something, just so I can go a little faster. My buddy and I hit 130 in his Z28. Yeah, its stupid. But we're still setting the goal at 150 (but possibly somewhere safer like the drag strip). Oh well, just curious. __________________ "The people should not be afraid of their government. The government should be afraid of it's people." "The Hurricane" 1967 Chevrolet C10 350 Eight Cylinder, 700R4 BowtieOverdrive *Cherry Bomb...* Disturbing the Peace Since 1968.

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