Anyone running 4.88 or 5.13 gears ? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

mikep · 03-03-2003, 12:19 AM

Trying to figure out what gear I'll be installing in the Dana. Anyone running 4.88's or 5.13's with a 32 inch tire ? How do you like it ? I'm not worried about mileage since this has turned into a toy. I can dolphin it if I need better mileage anyway. Or is that porpoise it? I get my marine mammals mixed up .

miket · 03-03-2003, 01:26 AM

Mikep,

I have 4.11's in my 9inch on my Chevelle. I changed them from 4.56's to make it a bit streetable which it does. But, I really liked the 4.56's 'cause it let the motor run in the range it needs to and launched well.

Not sure what you are trying to do with the Truck....I have 33" Mickey's on my Chevelle and a 5500 stall...that probably didn't help you... sorry.

pissonNOS · 03-03-2003, 01:27 AM

could someone explain the way gears work and what the numbers mean please?

1969 GMC · 03-03-2003, 02:55 AM

I'm a little new to the world of wrenching on vehicles, but I am pretty sure that the gearing number (like 3.73, 4.11, etc) is how many revolutions the engine must turn the driveshaft to turn the axle 1 revolution. Lower gears are higher numerically- 5.13s are lower than 4.11s even tho the # is higher. I think that lower gears are smaller, too (physical size).

crazy longhorn · 03-03-2003, 08:26 AM

mike try this link on ratio compairisons http://www.smokemup.com/auto_math/mph_range2.php I run a 4.10 gear on a 28" tire.....thats about as deep as I would want to be on the street. The 32" tires look real close , with a 4.56 gear. 4.88s are a few more revs........but the 5.13s are Ziiiing! My SB tachs @ 4000-4100 rpms running with the big trucks on the hyway,& they roll through Ill @ 80mph.........

mikep · 03-03-2003, 10:10 AM

Ive run a 27 inch tire with 4.10's before and didnt find it all that obnoxious. Since the 68 has pretty much been removed from highway duty at least for now thanks to GW Bush and his Texas string pullers running up the price of gas in the name of the freedom of the Iraqi people I am free to go with whatever gears will give me the best acceleration and allow me to reach a top speed of at least 115 mph at 6000 RPM. With a 32 inch tire that happens to be 5.13 gears. The gas mileage will go to hell but with the cam I am running I need more gear and 5.13 can fill that bill most nicely .

crazy longhorn · 03-03-2003, 10:25 AM

Just dont plan too many road trips! That is my only complaint on the 4.10s, trying to keep around 3200 on the hyway (so it dont slurp all the gas down) makes a long trip. I think you will find that SB to pull well past 6000 rpms with the lower gears.....

Mike C · 03-03-2003, 03:21 PM

Somewhere there is a law of diminishing returns to gear. For instance, my buddies '69 Firebird with a 2800 rpm converter at 3.42 ran 10.69 @ 123 going to 3.73 slowed it down and required more engine mods.

I think you will be most happy with the 4.10 and I know they are easier to find. The smaller displacement, usually the better they like more gear. If you get a 283, go for the 5.13! But with your combo, just get the 4.11. That is still a 20% increase over your 3.54.

Long Knight · 03-03-2003, 05:24 PM

I think it's a give and take game. If you want roasting action off the line those low gear ratios are the way to go, but remember they are LOW gears and when you start wrapping out it doesn't matter how many ponies you have, you won't go faster. Low gears make your engine reach it's mechanical limit sooner. But, sometimes it's enough to give you what you want. You can go faster with higher gears (or bigger tires), but you also need some extra hp to get get some good acceleration.

mikep · 03-03-2003, 11:51 PM

I'm running a 32 inch tire and my engines peak HP is in the 5500-6000 rpm range and it really doesnt fall off quickly after that . Its a pretty healthy cam Ive got in her now. The bottom end is built to live at 6000-6500 for the better part of a day too. Ive run big cams like this with 4.11's and 31 inch tires before and from experience I'd say that is actually probably not enough gear for this combination and at some point I'm probably going to go to a 3500 stall converter. I'm actually leaning more to the 4.88 gears than the 5.13's. Thats still going to put me in range of peak HP at 110-115 miles per hour which is as fast as I'd like to take this pig.

jhow66 · 03-03-2003, 11:55 PM

5.38 posi in my Pro Street 56 Chevy--hums pretty high even with 31" tires.

Long Knight · 03-04-2003, 10:13 AM

jhow,
That is awesome!

jhow66 · 03-04-2003, 11:37 AM

Thanks Long Knight. Here's what it motivates:

Long Knight · 03-04-2003, 12:19 PM

Beautiful car! A while back I was trying to pry a '56 2 door post from an older lady. It had 26K original miles, always kept in a barn. I just couldn't get her to let it go. Do you have any pic. of the inside of your car.
By the way, that's a good looking truck in the background!

jhow66 · 03-04-2003, 09:16 PM

Click on my web site at bottom of reply(www). It has pictures and gives info on car--page 2 is my truck--other pages are the cars I help build for some of my friends.

Snowbound · 03-04-2003, 10:53 PM

How about putting a 9" Furd under the rear and have two center sections ready to go. One for racin' and one for cruisin'. I'm not sure what gear ratios are available for the 9", but it's pretty popular.

Drive to the track, drop out the hiway gears and slide in the big boys. There's a few racers that do this who can't afford tow rigs etc. Just a thought.

Brian

pat · 03-04-2003, 11:05 PM

I envy you jhow66

mikep · 03-04-2003, 11:47 PM

Quote:

Originally posted by Snowbound
How about putting a 9" Furd under the rear and have two center sections ready to go. One for racin' and one for cruisin'. I'm not sure what gear ratios are available for the 9", but it's pretty popular.

Drive to the track, drop out the hiway gears and slide in the big boys. There's a few racers that do this who can't afford tow rigs etc. Just a thought.

Brian

To be honest I'd just as soon keep the 3/4 ton carriage and the 8 lug full floater Dana. I have a thing for Dana 60's. I like the stiff/high ride of the truck . Its not a truck that might ever see the highway again so long trips with it are pretty much out of the question. Besides that the local race track is 5 miles away. 4.88 gears with a 32 inch tire doesnt seem unreasonable for a truck thats not a daily driver. So I'll get 5 mpg and run 4000 rpm at 70 mph. If I put 5000 miles a year on it from now on I'll be shocked.

72CustomCamper · 03-05-2003, 12:44 AM

jhow66-

A little off the subject of the thread...but what is that gauge at the bottom of the pic? Temp, vacuum?

cali_surfer · 03-05-2003, 12:50 AM

Probably a fuel pressure gauge

jhow66 · 03-05-2003, 11:27 AM

Temp gauge--one on the other side just like it is oil pressure. Just setting around one winter thinking up things to do and came up with these. Made them out of alum. road signs and polished them. If you look up to the top of picture you can see the fuel pressure gauges for carb and NOS. Mikep I drive my 56 even on the interstate --just have to watch the fuel gauge. lol

UNCLEBOB · 03-06-2003, 01:19 AM

Racing my truck last year with 30 inch slicks I was going thru the traps at about a 100 at 5500 rpm. That was with a 4.57 gear. If you are going to run 32s I would go with the 4.88 or 5.13s

03-03-2003, 12:19 AM	#1
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Anyone running 4.88 or 5.13 gears ? Trying to figure out what gear I'll be installing in the Dana. Anyone running 4.88's or 5.13's with a 32 inch tire ? How do you like it ? I'm not worried about mileage since this has turned into a toy. I can dolphin it if I need better mileage anyway. Or is that porpoise it? I get my marine mammals mixed up . __________________ No truck :-( Last edited by mikep; 03-03-2003 at 12:21 AM.

03-03-2003, 01:26 AM	#2
miket Registered User Join Date: Jan 2003 Location: Seattle WA Posts: 1,466	Mikep, I have 4.11's in my 9inch on my Chevelle. I changed them from 4.56's to make it a bit streetable which it does. But, I really liked the 4.56's 'cause it let the motor run in the range it needs to and launched well. Not sure what you are trying to do with the Truck....I have 33" Mickey's on my Chevelle and a 5500 stall...that probably didn't help you... sorry. __________________ FocuzTech Performance Evergreen Protective Coatings Gatorhyde...the best kept secret in spray in bed lining & protection

03-03-2003, 01:27 AM	#3
pissonNOS senior member Join Date: Feb 2003 Location: fort macleod alberta Posts: 2,770	could someone explain the way gears work and what the numbers mean please? __________________ 69 GMC bagged

03-03-2003, 02:55 AM	#4
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	I'm a little new to the world of wrenching on vehicles, but I am pretty sure that the gearing number (like 3.73, 4.11, etc) is how many revolutions the engine must turn the driveshaft to turn the axle 1 revolution. Lower gears are higher numerically- 5.13s are lower than 4.11s even tho the # is higher. I think that lower gears are smaller, too (physical size). __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

03-03-2003, 10:10 AM	#6
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	Ive run a 27 inch tire with 4.10's before and didnt find it all that obnoxious. Since the 68 has pretty much been removed from highway duty at least for now thanks to GW Bush and his Texas string pullers running up the price of gas in the name of the freedom of the Iraqi people I am free to go with whatever gears will give me the best acceleration and allow me to reach a top speed of at least 115 mph at 6000 RPM. With a 32 inch tire that happens to be 5.13 gears. The gas mileage will go to hell but with the cam I am running I need more gear and 5.13 can fill that bill most nicely . __________________ No truck :-(

03-03-2003, 08:26 AM	#5
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,403	mike try this link on ratio compairisons http://www.smokemup.com/auto_math/mph_range2.php I run a 4.10 gear on a 28" tire.....thats about as deep as I would want to be on the street. The 32" tires look real close , with a 4.56 gear. 4.88s are a few more revs........but the 5.13s are Ziiiing! My SB tachs @ 4000-4100 rpms running with the big trucks on the hyway,& they roll through Ill @ 80mph.........

03-03-2003, 10:25 AM	#7
crazy longhorn Fabricate till you "puke" Join Date: Jun 2002 Location: Ill Posts: 9,403	Just dont plan too many road trips! That is my only complaint on the 4.10s, trying to keep around 3200 on the hyway (so it dont slurp all the gas down) makes a long trip. I think you will find that SB to pull well past 6000 rpms with the lower gears.....

03-03-2003, 03:21 PM	#8
Mike C Registered User Join Date: Dec 1999 Location: Austin, TX, USA Posts: 7,713	Somewhere there is a law of diminishing returns to gear. For instance, my buddies '69 Firebird with a 2800 rpm converter at 3.42 ran 10.69 @ 123 going to 3.73 slowed it down and required more engine mods. I think you will be most happy with the 4.10 and I know they are easier to find. The smaller displacement, usually the better they like more gear. If you get a 283, go for the 5.13! But with your combo, just get the 4.11. That is still a 20% increase over your 3.54. __________________ 44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax

03-03-2003, 05:24 PM	#9
Long Knight Spank 'em if you got 'em! Join Date: Nov 2002 Location: Kansas City Posts: 628	I think it's a give and take game. If you want roasting action off the line those low gear ratios are the way to go, but remember they are LOW gears and when you start wrapping out it doesn't matter how many ponies you have, you won't go faster. Low gears make your engine reach it's mechanical limit sooner. But, sometimes it's enough to give you what you want. You can go faster with higher gears (or bigger tires), but you also need some extra hp to get get some good acceleration. __________________ Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick

03-03-2003, 11:51 PM	#10
mikep Used to have a truck Join Date: May 2002 Location: port orchard WA Posts: 1,552	I'm running a 32 inch tire and my engines peak HP is in the 5500-6000 rpm range and it really doesnt fall off quickly after that . Its a pretty healthy cam Ive got in her now. The bottom end is built to live at 6000-6500 for the better part of a day too. Ive run big cams like this with 4.11's and 31 inch tires before and from experience I'd say that is actually probably not enough gear for this combination and at some point I'm probably going to go to a 3500 stall converter. I'm actually leaning more to the 4.88 gears than the 5.13's. Thats still going to put me in range of peak HP at 110-115 miles per hour which is as fast as I'd like to take this pig. __________________ No truck :-(

03-03-2003, 11:55 PM	#11
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	gears 5.38 posi in my Pro Street 56 Chevy--hums pretty high even with 31" tires. Attached Images __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer

03-04-2003, 10:13 AM	#12
Long Knight Spank 'em if you got 'em! Join Date: Nov 2002 Location: Kansas City Posts: 628	jhow, That is awesome! __________________ Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick

03-04-2003, 11:37 AM	#13
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	Thanks Long Knight. Here's what it motivates: Attached Images __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer

03-04-2003, 12:19 PM	#14
Long Knight Spank 'em if you got 'em! Join Date: Nov 2002 Location: Kansas City Posts: 628	Beautiful car! A while back I was trying to pry a '56 2 door post from an older lady. It had 26K original miles, always kept in a barn. I just couldn't get her to let it go. Do you have any pic. of the inside of your car. By the way, that's a good looking truck in the background! __________________ Long Knight '71 C-20, 350ci, TH350, Edl. 1406 Carb w/elec.choke, Ignitor ignition, Viper Tires, Orange Dipstick

03-04-2003, 09:16 PM	#15
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	Click on my web site at bottom of reply(www). It has pictures and gives info on car--page 2 is my truck--other pages are the cars I help build for some of my friends. __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer



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03-04-2003, 10:53 PM	#16
Snowbound Registered User Join Date: Aug 2002 Location: Westbank, BC Posts: 401	How about putting a 9" Furd under the rear and have two center sections ready to go. One for racin' and one for cruisin'. I'm not sure what gear ratios are available for the 9", but it's pretty popular. Drive to the track, drop out the hiway gears and slide in the big boys. There's a few racers that do this who can't afford tow rigs etc. Just a thought. Brian __________________ 1965 Chevy Short Box Stepside, 230 - 3 speed, 4:11 gears, original paint rust free survivor. Now sporting a 383 SBC and TKO-600

03-04-2003, 11:05 PM	#17
pat Senior Member Join Date: Jul 2002 Location: Lindsay, TX Posts: 1,245	I envy you jhow66 __________________ 68 Chevy 383/350 w/shift kit, 380hp/425ft-lbs, 4.5/5 drop, 17" TT2s 64 Cadillac Sedan DeVille

03-05-2003, 12:44 AM	#19
72CustomCamper Registered User Join Date: Feb 2003 Location: Bremerton, WA Posts: 86	jhow66- A little off the subject of the thread...but what is that gauge at the bottom of the pic? Temp, vacuum? __________________ '72 GMC C20, "2500 Super Custom", Custom Camper, New 454 '93 K2500 Suburban, Old 454 (157K)

03-05-2003, 12:50 AM	#20
cali_surfer Registered User Join Date: Jun 2000 Location: Chico, CA Posts: 1,136	Probably a fuel pressure gauge __________________ My engine is stock... trust me ;o)

03-05-2003, 11:27 AM	#21
jhow66 Registered User Join Date: Jun 2002 Location: Knoxville Tenn. Posts: 3,058	Temp gauge--one on the other side just like it is oil pressure. Just setting around one winter thinking up things to do and came up with these. Made them out of alum. road signs and polished them. If you look up to the top of picture you can see the fuel pressure gauges for carb and NOS. Mikep I drive my 56 even on the interstate --just have to watch the fuel gauge. lol __________________ 56 Chevy Bel-Air 2dr. HT (purchased new) 71 Chevy Cheyenne SWB PU (502HO) 65 GMC short bed step--work in progress and my gofer

03-06-2003, 01:19 AM	#22
UNCLEBOB Registered User Join Date: May 2000 Location: bremerton wa 98310 Posts: 100	Racing my truck last year with 30 inch slicks I was going thru the traps at about a 100 at 5500 rpm. That was with a 4.57 gear. If you are going to run 32s I would go with the 4.88 or 5.13s __________________ 68 lwb 383 solid roller,250dur, 582lift, afr 210s, 10.8 comp. edel.rpm, 750vs,1 3/4 headers turbo 400, 3500 stall,ford 9 inch 3.89 gears

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