1/4 mile times.

[jonboyNY]

Was at englishtown today, got a 15.785 1/4 time. on 22" rims LOL.

Aside from this, been doing alot of research on this truck and problems I have been facing.

What has come forth is a very interesting problem:

-4.10's are weak gears period.

If you are going to increase your torque by over 400 RWTQ you will have serious problems with stock 4.10's. Even at 290+ which I have now have caused me major problems with the driveline after replacing them 3 times in 20 days.

GM techs are involved in this, and their own words are if you going to push the limits of the truck you are going to be safe and only safe with 3.73's. This is why they put them on trucks and only usually give an no option on 6.0L trucks.

The new 2004 will have 3.73's in them. I test drove the 3.73 ratio, to be honest the 2003 with the 3.73's is pretty quick, I think quicker then the 4.10's especially when you hit 30MPH. The 2004 is even quicker.

Just food for thought.

Thanx guys.

[11H]

jonboyny,,,

 Whenever I have seen a question on this board about 4.10 vs. 3.73 I have always said the 3.73 was a stronger gear set ...  More meat ...

 It is one of the benefits of the 3.73 in our 8.625 Rear Diff ... I also will say a 5.3 or GM stock truck will dyno higher with the 3.73 vs. the 4.10 ... The gears in the tranny and the way the motor is inletted marries better in the power curve dept. with the 3.73 ...

 There is more power under the curve over a bigger area with the 3.73's ... That's maybe why you feel the surge more with the 3.73 once the av gets off it's behind ...

 The large benefit to the 4.10's is really only off-idle getting off the line ... But like you said, once you are rolling the 3.73's "should" come on stronger ...

11H

[PUNISHER]

   you enlighten me everyday 11H.  i always thought the 4.10 was always the better of the two; for quick 1/4 mile action.  but what you explained makes sense.

[11H]

  you enlighten me everyday 11H.  i always thought the 4.10 was always the better of the two; for quick 1/4 mile action.  but what you explained makes sense.

 I know someone will refute this, so I will detail a bit more ...  

 It's not always the case, especially in bracket cars ... The difference is that a bracket car has a driveline that stays peaked near red line and to do that, deep gears are needed along with many other things matched for the optimum rpm range of the motor (converter, close ratio gears, etc.) ...

 On trucks like ours with a relatively low RPM HP peak, I have seen consistently, results where 4.10's peaked the motor sooner and fell off on RWHP vs. 3.73's ... That's power under the curve over a smaller operating range ... Again, it depends on the inletting, cam, exhaust, max rpm, etc.

 More power under the curve with the 3.73's will not necessarily get you through the 1/4 mile faster, as the launch time is a major factor where deeper 4.10's will help, but where jonboy says the 3.73's feel "faster" above 30 MPH, indicates they are doing better than the 4.10's in a certain RPM range ... I had 2 trucks once, a 3.73 Z71 Extra Cab and a 4.10 Z71 extra cab ... I owned the 4.10 truck first ... When I bought the 3.73 truck, (same truck config) the 3.73's felt gutsier once the truck got moving ... The 4.10 truck revved quicker, but the 3.73 truck felt stronger ...

 Plus, as he said, you could expect the R&P to handle more shock and torque just because there's more material and also, since the 4.10's carry more torque multiplication, the rear carrier is exposed to more forces too as are the axles ...

 Ask Gandy what happened to his dyno sheets when he went from 3.73's to 4.10's ... Now in a big 8.1 that change may not have helped his cruise acceleration as there's an abundance of torque everywhere, but for sure his launch was better hence the ET better just due to a lower 60' time ...

 Saying all this, if I were to creep over the edge with a supercharger, I would defenitely keep the 3.73's in my 1500 av ... No doubt ...

11H

 

[jakom]

How do I know which gear ratio I have?

[AVid]

How do I know which gear ratio I have?

Check the RPO sticker in your glove box...

GT5--4.10
GT4--3.73

HTH   John

[Redshift]

Ok H,

I understand the gear theory but my latin is weak. Diligence with swiftness of action??? My WAG. What's the real translation?

kw

[11H]

Ok H,

I understand the gear theory but my latin is weak. Diligence with swiftness of action??? My WAG. What's the real translation?

kw

It's an old Jeff Cooper thing ... Accuracy, Power, Speed  ...

11H (DVC)

[jonboyNY]

11H, yes you have always said 3.73's are stronger.

The problem is this. Right now I have a dyno of 295.7 with the addition of electric fans. My 4.10 gears are wrecked period. Changed them twice, not only that, I have an Eaton posi which should of helped a bit with the force in the rear.

This all boils down to several convos with Lingenfelter techs, GM techs, and a few buddies of mine who are LS1 pros. These pros have 11-12 sec chevy trucks. They all have 3.73 gears in them. One guy changed them from original 3.73 to 4.10 and front and rear diffs, back to original 3.73's...and silverados are lighter then our trucks. The 4.10's could not handle the torque at all.

All these big name houses like Lingenfelter, only like trucks with 3.73's...thus GM only gives 3.73's on trucks with 6.0L engines...they offer them on the 5.3's because they dont believe to many people will modify them so much to cause a disruption or breakage in 4.10 gears in that particular engine(5.3L).

In referrence to the off the line performance...you can fix that so easily, blower...cam...heads....tq converter....etc. Thats no problem....N/A engines also, but you must have a good head and cam package maybe with some NOS...depends.

I am so sick of the whole situation with my truck, that I am getting a new one for free. LONG STORY but thats whats happening LOL They taking the 03 and swapping for a 04 with 3.73s.

Remember, if you going to go all out with this truck and make this beast really move like I will....you going to want 3.73's so that way you will have more longevity with your drivetrain.

If you do simple bolt ons like exhaust, intake, headers with a blower you should be fine for awhile with the 4.10's but sooner or later they will tear up.

My truck ring and pinion literally cracked the 1st time, 2nd time the bolt that holds the peices popped straight through out grinding. COMPLETELY DISGUSTING, im so irritated. My f*#king 91 MB 560SEL MINT with 100,000 miles has never seen the shop for anything but normal maintenance. I didnt expect this for a 03 5 month old 9600 mile truck to have these problems. BUT, I still love the AV LOL and thats why I am going with another shot at it.

Hope this info helps.


By the way...SLP is comming with headers (shortys) for 5.3 engines....which they have documented proof that they beat the JBA's by 5-7 RWHP. Should be out by November.

Thanx.

[jonboyNY]

Aside from this...they had a lightening that did 11.78 last night at Englishtown...slicks no tailgate and pretty good diet from what i saw but still had seats. Thats sickkkkkkkkk!

[avy_fluke]

JonBoy,

SLP is coming out with Shortys?  I have to wait now since I was going to get the JBAs.  Thanks for the heads up.

-AF

[jakom]

Thanks AVid

[TruckZor]

I've never really believed that a 10% change in gearing was worth all that much in the 1/4 unless you're talking about a drag car that can launch at full throttle with slicks (in which case the advantage would be shown in the first 60 feet)...or if the gearing is used to optimize the RPM level at the finish line.  In both of those cases...the gearing can make a big difference.

When I was stock I raced a stock Silverado extended cab with the 5.3 and 4.11s, which I believe had a pretty good weight advantage on me.  His truck jumped out a little harder off the line but mine kept a nice steady pull going with my 3.73s.  In the end, he kept the 1/2 - 1 truck advantage that he took primarily off the line but he simply could not lose me once we were rolling.

Unless towing is an issue...or if you just have to have that feeling that the lower gears give you...I would recommend the 3.73s to anyone.

Also, my old LS1 camaro was absolutely no faster with 3.73s vs. the 3.42s on stock tires.  The car felt faster and was more fun to drive...but whatever advantage the gearing gave was lost to the more frequent shifting.  If I had some drag radials on it, I'm sure the 3.73s would have been the quicker gear...but then parts breakage would have been even more of an issue and even on stock tires I sheared teeth off of both the ring gear and the pinion gear...not fun!!!

[ygmn]

Jonboy,....you add all that stuff to create more horsepower (Blower, intakes, electric fan etc etc) way over stock and then complain when something breaks in the drivetrain.....??

Help me understand......GM gave ya new one......even though you increased Hp that much over stock?

[11H]

I've never really believed that a 10% change in gearing was worth all that much in the 1/4 unless you're talking about a drag car that can launch at full throttle with slicks (in which case the advantage would be shown in the first 60 feet)...or if the gearing is used to optimize the RPM level at the finish line.  In both of those cases...the gearing can make a big difference.

When I was stock I raced a stock Silverado extended cab with the 5.3 and 4.11s, which I believe had a pretty good weight advantage on me.  His truck jumped out a little harder off the line but mine kept a nice steady pull going with my 3.73s.  In the end, he kept the 1/2 - 1 truck advantage that he took primarily off the line but he simply could not lose me once we were rolling.

Unless towing is an issue...or if you just have to have that feeling that the lower gears give you...I would recommend the 3.73s to anyone.

Also, my old LS1 camaro was absolutely no faster with 3.73s vs. the 3.42s on stock tires.  The car felt faster and was more fun to drive...but whatever advantage the gearing gave was lost to the more frequent shifting.  If I had some drag radials on it, I'm sure the 3.73s would have been the quicker gear...but then parts breakage would have been even more of an issue and even on stock tires I sheared teeth off of both the ring gear and the pinion gear...not fun!!!

Amen zor ! ... Just re-inforces my theory about 3.73's vs. 4.10's ...  

Now that I have side stepped the PE delay in the PCM off the line, I am much happier with my 3.73's ... I defenitely wouldn't trade them out for 4.10's unless I had a lift & tires in mind ... Which I won't in a 1500 chassis ...

BTW, I thought stock gearing in the F-Body with the perf axle option was 3.23 ? ... (Best ratio for an Auto F body IMO) ... I raced 3.73 cars and even some 4.10 cars with autos and there was no difference ... LOL ... My second gear pull was the killer ... They would hit 3rd gear and I was still at the top of 2nd ... BYE, BYE !

-------------------------------------------------

jonboy,,,

 Thanks for all the good info on the 3.73's ... Very good info you have hunted down... It makes me feel great when folks like LPE and the likes agree with me on something ... Uhhh, Errr, Or is it I agree with them ? ... Oh well ... I think the 8.625 is "happier" getting "pushed" with the 3.73 ... Always have ! ... We are absolutely 100% parallel in our thinking on this one !  

11H

[Dazed Dave]

Does anyone have the digits for a stock Z66.  I'd like to start the performance mods soon, and I'd like to know if anybody already has the numbers for a baseline.

[11H]

Does anyone have the digits for a stock Z66.  I'd like to start the performance mods soon, and I'd like to know if anybody already has the numbers for a baseline.

Expect about 5-8% more than a 4x4 (the Z66 also has an aluminum prop shaft which helps too) ... I would venture an avg baseline would be about 225 RWHP ... In summer 80-90 degree temps ...

Mine in the 4x4 was 218 at 95 deg, 14% humidity, at 1000 ft ... Repeated run was 216 ...

I'm at a best of 248 with the procold, magnaflow cat back, TV50 wires, and NGK TR55 plugs with oem tuning and PCV sucking oil ... My worst was 244 ... Which was the third run in back-to back pulls ... I expect that the custom stuff I've been doing with Diablo and my PCV system fixed will give me between 12-18 More ...

Then I'm done ... (Well, unless JET HOT comes out with some cheap Long Tube Headers) ... I will have the HP equivalent of the stock EXT 6.0 without the headers ...  

*** Disclaimer: All these numbers were generated with the hood CLOSED in a non-air conditioned shop with a swamp cooler ...  

11H

[Dazed Dave]

Thanks.  I know I should be quicker, since I'm not as fat as the 4 X 4 guys.  But, I don't know what the weight savings gets me down at the other end of the strip.

[11H]

Thanks.  I know I should be quicker, since I'm not as fat as the 4 X 4 guys.  But, I don't know what the weight savings gets me down at the other end of the strip.

This is a very general rule of thumb ... For evey 100 pounds you can shed from your vehicle, your ET should drop about one tenth of a second ... A truck length is about 3 Tenths ... This is very general due to the variables involved and the power to weight ratios are different, but this is a fair estimate ...

So If you raced a bone stock 4x4 and a Z66, I am betting all things being equal, you should have oh, about a truck at least on one, and maybe at best a truck and a half ... A truck length being his front bumper is at your rear bumper when you hit the traps ... (1/4 mile)

Taking this one step further, a late Gen F Body (Z28 or TA) needs to add 10 RWHP to gain one tenth ... They weigh about 3500# and have about 300 RWHP and are fuel injected ...

So, saying that I would bet you need about 12-13 RWHP added to a 4x4 av to get another Tenth ...

(Now all these assumptions don't take into account driver skill, so I don't want to argue about "Joe can't beat my 1500 av with his reg cab silverado" kinda stuff ... Great, then maybe Joe is hitting the gas 7 or 8 tenths later than you ... (big difference when you don't have a precision clock to gauge with)

11H

[TruckZor]

...BTW, I thought stock gearing in the F-Body with the perf axle option was 3.23 ? ...

You are correct...mine was a 6 speed, though.  

[11H]

...BTW, I thought stock gearing in the F-Body with the perf axle option was 3.23 ? ...

You are correct...mine was a 6 speed, though.  

Ahhh yes, then 3.42 it would be ... (snicker) ... I know ALOT of guys running 4.10's and that 6th gear still gets great mileage ... Although that brittle 7.5 rear diff don't like 4.10's and coming out of the hole at 4,000 RPM with drag radials ...  

If I were to build another Camaro, it would again be an auto ... Just because I don't have $2500 to put a strong rear-end in it ... I'll take the auto ... Better driveline lash control ...  

11H

[TruckZor]

I certainly wouldn't fault you on that decision.  I happen to love driving the 6 speeds...just so much fun.  However, my mother has a 2000 WS6 TA with the auto and that car ran a 13.4x at 104.7 at last year's SLP day...bone stock and with a bunch of crap in the trunk.  That was on a day when my brother's SS was running 13.6s at 106.x.  His car had previously run a best of 12.99 at 110.5 so times and trap speeds were off that day to say the least.  The autos are just mean at the drag strip.  

[11H]

I certainly wouldn't fault you on that decision.  I happen to love driving the 6 speeds...just so much fun.  However, my mother has a 2000 WS6 TA with the auto and that car ran a 13.4x at 104.7 at last year's SLP day...bone stock and with a bunch of crap in the trunk.  That was on a day when my brother's SS was running 13.6s at 106.x.  His car had previously run a best of 12.99 at 110.5 so times and trap speeds were off that day to say the least.  The autos are just mean at the drag strip.  

 I like this ! ... Yes, I believe the 6spd is ruthless at the track if the surface is working for you ... But if it's not, the auto can be less of a guessing game... If you feel some slippage, you can modulate .... But when you have a manual, first gear is somewhat commited when you drop the clutch ... IMO

 That is a great time on that mom's auto ... I am venturing to say she doesn't have the std 2.73's ? ... The LS1 is a DOG with them gears so bad that low 14's here are the norm ... The LS1 likes 3.23's so much better in the 60' area ...IMO ...

 BTW, I "had" several LT1 F Bodies and got rid of them when the LS1 came out ... I had it modded with every bolt on you could do except headers... I mean everything ! ... My best dyno pull was 268 HP / 289 TQ ... My best here at Firebird was a 13.90 @ 100.05 W/ 2.01 60' in the summer at about 90 degrees (stock converter, street tires, 3.23's) ... All the LS1's in 98 were mostly autos here with 2.73's and were pulling off low 14's ... But with traps better than mine most of the time ...

 The months before I traded my car off was when I messed with a guy in a black 98 auto LS1 3.23 ... We hit it on a roll (I held it in 1st L1) from about 20 MPH ... We ran up to 90 or so... I jumped him about a car right off the bat (LT1 Torque) and at 75 or so, he started coming and put a little over a car on me and we shut it down ... We pull over and he says that I would be a good run for his buddie's 97 C5 as he gets him about the same ... LOL ... He had a bone stocker (strong cars man) ... I had over $1500 invested and my baseline bone stock was 239 RWHP so the 268 was a great turn from stock ... I made all them gains with the right mods, and was getting eaten alive by stock LS1 Z's ... My death of the 96 Z28 (traded in that week) was another on the roll race with a 98 SS 6spd ... He did almost as good as the guy with the 98 auto ... My best bud has a 2000 Z28 Auto no converter, and stock trans running high 11's on Nitto Drags ... His RWHP off bottle is 338 ... His 100 shot dry kit is netting 80 RWHP or so over that ... The main mods he has is 3.73's, SLP longs, MAF, No O2's, LS1 Edit tuned, Lid, and true duals with Dynomax bullets...

I will say that if I ran off a light, I could hold off most LS1's to 100 MPH, but it was over by that speed cuz I figured I hit the 1/4 mi at which point I would get on the brakes ... (But most can't drive an LS1 to it's potential) ...  

11H

[TruckZor]

The WS6 gets the 3.23 ring and pinion as part of the package.

My father had a '94 Formula with the 6 speed, which I drove extensively in the late highschool/early college years.  It was around right up until a couple years ago when an errant S10 removed it from circulation permanently.  The LT1 torque was brutal in the first two gears.  Going against my LS1 from a roll in third gear it would always get beat pretty badly, though.  That car was a low option (very light) car with a particularly strong engine from the factory.  We always had it pegged as a high 13 second car, bone stock with a good driver.  I still like LT1 cars a lot.  I don't typically buy used cars but I see some very nice late model LT1s out there with extremely low mileage that are very tempting.  Parts are so much cheaper for them  

You are correct...it takes a very good driver to extract full potential from an LS1 with a 6 speed.  My mother is very good with a manual transmission (she also has a Z06...I'm not kidding) but you kind of have to beat on the car to get those last few tenths out of it, which she won't do, so she's better off with the auto...she doesn't lose many stoplight encounters with her WS6...it's a really mean car and all you have to do is hit the pedal on the right.  

I, on the other hand, think it's great to hear the tires bark going into fourth gear    I never dropped the clutch on the launch...I prefer to slip it.  I admit that it beats the hell out of the clutch but there is no beating the control you have as far as modulation.  There was nothing quite like the feeling of riding it out just right...keeping that nose in the air the whole way through first gear  

By the way, funny story on how I wound up with an Avalanche...my factory order for a Sebring Silver 2002 Z28 with no t-tops (I was planning an all out ported heads/ solid roller cam car with a 12 bolt rear) was cancelled when the factory shut down a little early    I had already sold my Z28 and needed a car.  They were really dealing on the 2002s and after a test drive I loved the truck.  The structure really is so much stiffer than a Suburban or a Tahoe.  So I guess now you know why there is a Magnuson under the hood    I love driving my Avalanche every day...the Camaro really was an uncomfortable, slightly useless vehicle...but it sure was fast.

[Butch]

Im surprised your having problems already with your 4.10s jonboy.., my 4.11 gears and Eton posi are still doing fine with 12000 miles on them.., and im putting some pretty high power to them.. I did make sure the set up was perfect.., and run a tight backlash on the gears (.006 thou) this helps with the shock loading on the gears.... My gear ratio with the wheel tire that I run is 3.89 which I find is about perfect going through the quarter... My friend who is an ace at setting up rear ends and I did spend a whole day on them to get them set up perfect.. I do drop and change the gear lube oftend to check on them.., and since I installed them the back lash is still right at 6 thou. and there is no signs of trouble with them.. I run 80-140 RedLine syn. in the rear, and so far with 12000 miles and 4 trips to the track no problems..., the set up does have a lot to do with gears lasting... Going to the track one more time before the weather goes bad to take advantage of this good cool weather, and see what my latest changes have done.........

Im am going to ditch the 10 bolt and install a custom ford 9 inch rear before I put the stroked 6.0 in though... Moroso's fab shop did one on a Denali that I saw and it was beautiful..., couldn't even tell that it didn't have the stock 10 bolt still in there.., set it up with the stock spring pads, control arms, and suspension pick up points.., was sweet

Butch.

[inSaNE iRIsH]

Ok, so here’s a question, I am trying to decide specifics to order my AVY…if my plans are to lift it, put 33-inchers on, and use it for drag racing & offroading…it will be a 4x4

1)what setup would you recommend ordering? 1500 or 2500?  Which engine? Which final gear ratio? Etc

2) what mods for power…looking for 12-13 seconds as economically as possible without totally destroying reliability & street drivability

thanks

[OviedoAv]

I have just one word to say...[glow=red, 2, 300]BIG BLOCK[/glow]...oh wait, thats 2 words

[tbyrne]

I'm also surprised you tore up a few sets of gears already. How do you launch at the track?

I'm probably going to be taking some 1/4 mile runs tomorrow if it doesn't rain. My 8.1 Suburban dynoed 407hp/558 ft-lb last week so hopefully the 4.10s will live through that

Tom

[Breedlove]

Hey 11h, do you think the 3.73's will be ok with 35 inch tires?  Obviously I will need to change the exhaust and such for more power so that it doesn't bog down.  I love playing in the dirt, but on the freeway I love punching the gas.  Thanks again (as always) Breedlove

[11H]

Hey 11h, do you think the 3.73's will be ok with 35 inch tires?  Obviously I will need to change the exhaust and such for more power so that it doesn't bog down.  I love playing in the dirt, but on the freeway I love punching the gas.  Thanks again (as always) Breedlove

No they will lug badly in the lower RPM's and speed ... (If you have the 1500 avalanche) ... You'll need the 4.10's ...

11H

[ChevyAV2003]

This is my own 2cents. so take it or leave it. I had a '01 silverado ext cab with the Small v8 block in it ( Which i traded in for my AV ). off the line it was definately quicker than my '03 AV z71 (lighter truck of course). Now note both of these have a 3.73 rear end in them. I do notice though as has been mentioned that when I hit around 27-30 range that it kicks it up a notch and really starts flying. I can maneuver it to do it sooner or later depending on how I hit the gas off the line or while rolling. Both of these trucks are pure stock with no mods. Of course as also mentioned there is alot of back end to the AV pickup and to push. So the 4.10 would be the better at getting it off the line.  Of course this is loosley based on what I have seen and what I understand to be true. Since I do not possess the full technical garbal of understanding it all, do not quote me on this.

Thanks

me

[marc_w]

Johnny, what brand gears are you runnin?  Stock GM stuff???

I don't know though...  Aside from a diesel, it's gonna be real hard to convince me 4.10's aren't better than 3.73's.  Especially in a small block that likes to rev.

[jonboyNY]

Well LOL. the gears are stock GM stuff. Ask around do research, talk to the pros. 3.73's are THE BEST OVERRALL gears, they are stronger then 4.10's period. Just ask GM.

4.10's will launch you faster to a certain degree, but I am willing to bet I can launch a truck with 3.73's just as fast as the 4.10's.

All I am saying, all the big dawgs who do major work to these kind of big trucks would rather have 3.73s then 4.10s for future longevity.

And I can tell you personal experience which I REALLY HATE about the 4.10's. Once your up to 65-70 miles and hour and you punch it, it drops to 2nd I believe, you feel the truck move, but its STILL SLOW.
I tried with the 3.73's...NOW WE TALKING A PUNCH. I took my truck past 120.....the truck is a fat pig LOL with the 4.10s....the 3.73s are a dream.

Thanks.

[whitethunder]

I guess it's a matter of personal choice and deciding what you are trying to accomplish.

If you trying to go for pure accelaration the 3.73's would be my choice but if you are going to be going off road and towing then the 4.10's are the logical choice.

It's great to see so many people enjoying the Avalanche.

[DragonSlayer1]

LMFAO !


G.

[whitethunder]

LYFAO

[DragonSlayer1]

Yeah, L"M"FAO"
 

The 5th. is coming fast Ira, not fast enough

G.

[whitethunder]

   
if you keep L"Y" FAO you wont have any "A" left to sit on!!!
 

I'm looking forward to the 5th as well. I told YAK you and I would have a Orange Juice toast on him and send him the bill.

ha ha ha

[Flyer7717]

 

[russellisabel]

i dont really know what to make of this debate, I had liberty gear send me a 4.11 set up that looked way beefier than my stock gm gearsets, and im procharged with alky meth injection, mad boost ect. dynoed previous set up at 525rwhp and now looking at more than that with recent mods.. will know in a few days after finishing dyno runs and this AV runns in the 12's on 4 micky tomp 26 inch drag raid"s the 4.11 made the best combo for me and i've had zero issuses to date.  the only way I would really know would be to dyno two av's with the same power(say same year same engine same weight and tire size) on a dyno one with 3.73 and one with 4.11 how ever thats my 2 cents