Before I put in my stall, I had 3.73's already installed. It really woke up the car and helped from take off, compared to the stock gearing. Even on highway being an A4, it would move pretty good.

But now with a 4K stall and the gears, a total difference. I hit a 11.6 @ 116mph with just a ls6 cam + bolt-ons. Got a lousy 1.7 60' but I need more seat time.

Honestly, I think if you stay with the 3.42 there wouldn't be that much of a difference. My stall feels tight with my gears, and thats how I like it. I cruise on the highway at 70mph around 2600.

 

I don't know your setup- Im assuming you're running a much bigger cam, maybe your not...I have no clue what you have. 6500rpm is an arbitrary number that I happened to use for a calculation based on a setup I had in mind

My point is numerically higher gearing is not a stupid way to make an A4 quick and if you properly build a setup you've done the calculations based on what you have i.e taking into account what your redline is based on YOUR setup.

Cliff notes: If you're not going through the traps at redline, you're leaving power/time on the table - Hence why gearing your car properly with a higher gear is not stupid.

No read above- Im pointing out his comment regarding gearing a car higher is stupid. It's not- gearing a car numerically higher without considering the calculations for your setup is stupid. If your setup calls for 3.73's so that you go through the traps a damn near redline, that is what you want.

I currently have 2.73's in the 10 bolt and 4.10's in my Ford 8.8 that is being swapped in off the v6 shortly. 4.10's are being replaced with 3.73's

 

Young Jedi you have much to learn. I don't even know where to begin. 4.10 gears in an A4 with a slow car is lame. You should test and race more and give advice less. You may be surprised to learn you don't know everything.

 

LOL if you say so...

 

Humor me and tell me what you have done with your car. Show me the results of your great knowledge.

Ls1tech. Home of the keyboard racers giving bad advice on performance mods they have never done.

 

This is false. You do not want to be "at red line". Its ideal to be at or past peak power in your 1:1 gear, which for most NA cars isn't red line as it is. If your car carries power all the way to 6800 before it starts to fall off, and red lines at 7400, thats more like a margin of error for not having to shift again before you hit the end of the track. Not to mention, with any power adder, this isn't as important anyway because they don't typically have the peaking that NA cars have.

Also Gator saying he had a 275/60, which typically is a size for a 15" rim, that means its a 28" tall tire.. Fitting something larger than that in a 4th gen requires a lot of extra work. As you said he needed something larger to combat his car "legging it out" in the back end. I would say that is a proper strip set up already LOL. Considering there's guys running 26" tall tires in the 1/8th at ET's less than 5 seconds.

 

And just throwing this out there.

From my understanding (not a expert on the subject), what your asking more correlates to engine power Vs Weight, and the need for more wheel speed. There are a bunch of threads about this subject on bullet and on specific transmission/converter manufacturers websites.

Not to mention the way a converter stalls and is designed plays a huge part in this. The same converter will not stall the same on 2 different vehicles.

Converter is much more important for torque multiplication than gears. I believe your falling back on logic with a manual car?

 

Any links to said threads on the bullet or search terms to use for that info you mentioned?

 

Building it- I'd be more than happy to show you the results of the ls1 this spring

As for bad advice, I didn't realize my original question was bad advice nor was defending a modification because YOU think it's gay.

I don't know what he has or what his setup is or on what car, he gave half a tire size. I'm not going to guess

See this is where I have to disagree and you can correct me if I am wrong here- If you have properly selected a converter it should flash at peak power, if it flashes at peak power your shift extension should not drop below that point which automatically puts you above peak power in any gear while full throttle.

If 6800 rpm is where your power starts to fall off, and it falls off to the point that it is at/below the power you would make on the shift to the next gear, why would you not be shifting at that point? It wouldn't make sense to hold it to 7400 rpm unless a) you're in 3rd gear and out of gear because you don't want to go into 4th, b) it's safe to spin your car that high.

If you are at that point though, you would want to change your gearing and or tire size to fine tune that point.


Example- lets take factory redline of 6000 rpm and tnmowtowns car for instance- lets say he is running a 26" tire and lets eliminate converter slip for the sake of argument- with a 3.73 gear he should be going through the traps at 5500-5600 rpm @115mph...would it not be better to be turning 5900rpm going through that trap instead? How would going to a 3.90 gear for instance not help his time?

I'm not seeing how gearing a car to its maximum potential is a step backwards or "gay" Please explain if I have something backwards...

 

Well I'm not going to correct you, because like I said I'm not an expert. I'm not saying anything is gay, if thats directed at me or not lol.

Converter should flash to right below peak torque, not peak horse power. I am most likely correcting myself from a grammatical error in my last post. Which peak torque is typically a good bit lower than peak horsepower as we know. Not correcting you either if peak torque is what you mean by peak power.

Now to answer your question. If your power band peaks at say 6800 in our example, the only logical reason you wouldn't shift is because your are already in your final drive gear. You do NOT want to shift into an over-drive gear at the track. Which in this case you should be getting pretty close to the end of the 1/4 (1/8th mile you wouldn't be having this problem unless your set up to run 1/8th mile).

You will always want your rev-limiter set beyond peak power so you don't worry about hitting it if your shift is delayed. Any decently built street/strip motor should be able to hack 7000rpm. If your making power to 6800, you should be able to spin past 7000 easily. Most hydraulic roller set ups with gentle lobes, GOOD lifters, light valve train parts, and a lot of control can make it to 7500 without valve float. This is of course all NA talk, and the RPM ranges I'm using would dictate some stout parts. This of course would be different with a boosted motor.

So yes, you would be in 3rd (final drive in auto's) and 4th in manual cars (for people who aren't paying attention to the thread). Yes using my example it would be safe to carry your RPM out to 7400.

You answered your own question saying you would want to fine tune with a gear ratio or tire size change, or both.

Using his car as an example, all your information is hypothetical. I haven't seen an LS powered car, even stock, run less than 6000 rpm at the track, its been so long I forgot where they set the factory rev limiter LOL. Maybe an LT1/LT4 set up. But for the sake of answering how I think it should be done, sure. If he crosses the trap at 5600rpm in his 1:1 gear, and he red lines at 6000, a gear change would most likely net him running out RPM. Especially once his 60 is better. If his car hooked up better, he would be peaking the track at a higher rpm with the set up he has now, due to the increased actual acceleration earlier in the track. If he added more power, and kept a consistently lower 60 foot than right now, he would actually want to move to a higher gear (numerically lower) to increase wheel speed and decrease rpm. This of course, to say he doesn't have a car that can rev past 6000rpm.

So in the end, thats all hypothetical. Your down to altering wheel speed with a gear change. Change too many variables with the motor, gears, tires, etc you will need a converter change.

I would rather have an engine safely 3-400rpm below red-line going through the traps as a guesstimate for personal preference. If your not making any more power, and you ran out of gears to change in to, your only option is to ride it out and not hit the rev limiter.

Of course this is all my understanding, and I'm not a professional by any means. Just a racer rowing the gears, I'll get back to auto's eventually.

 

Honestly, I would like it if someone would tell me how wrong or right I am too. This is all just my opinion on the matter.

 

Yes, you're right it is peak torque and right below it or right at it I think we are saying more or less the same thing here depending on how you look at it.

When I say redline I mean the last point at which you hit before you shift, not your limiter. So I can have a redline of say 6000 but my limiter is at 6400 for instance.

I do believe that 6000 is the stock redline / shift point for the LS1's, but without opening hp tuners I won't say I am 100% - plus it's early in the A.M and I havent had enough coffee to think straight lol

I believe we are saying basically the exact same thing - assuming you are still hooking up moving to a numerically higher gear would make you faster so long as you aren't running out of gear (i.e having to shift into overdrive be it A4 / M6). And I do agree, if your redline /shift point is 6000 rpm for instance, I would want to cross personally at about 5700-5800 rpm to give you some buffer room.

^^This is why I brought up the question at the beginning about why I am reading about so many guys who go to a high stall converter and go from a 3.42 gear to a 4.10 gear for instance, but see no difference in ET... I don't understand how that is possible unless it is because they are no longer hooking and if that is the case then it is not the gear that is the issue, it is suspension / tire related

Lastly, while I do agree with the proper engine parts we can spin to 7000+rpm, the 4L60E does not like to be spun that high at all- I haven't done enough research on the 4L80E to know what that can handle yet, so I can't speak to that point.

 

I have to agree here. He has a funny way of looking at things, but in his own mind he makes perfect sense. I love this line:

BUT YOU DO HAVE CONVERTER SLIP, which makes everything else you said retarded! Good luck with your goals fella

 

Ya- well unless you want to talk about a specific setup and a specific converter on that setup you can't account for converter slip...so for arguments sake I said not accounting for converter slip so that I could illustrate my point and we could discuss something with consistency. Obviously when calculating and accounting for you actual setup you would factor converter slippage when choosing gearing

As mentioned earlier- every car responds to even the same converter differently based on what is done to the car.

So far both of you havent come up with an explanation to the original question posed other than it's "gay" or "retarded"...great tech knowledge there...I'll be sure to write that one in the books

 

i run a 275/60/15. i am not sure where else a 275 tire isnt 28" tall when talking about a car that goes 1.2x 60'. Telling me or others to go to a taller tire tells me you read the jegs catalog too much.

I shift at 6800 rpm on a 404" street motor. Peak power is irrelevant on a nitrous car. SO lets not talk about mine. On a bolt on car or all motor car like an ls1 with an lsx style intake (broad power curve) - the peak power is also irrelevant. it will make power within a 1000 rpm or greater range. any decent converter will keep you there.

a properly matched and spec'd converter keeps the motor in the area where its going to accelerate the best. this is where a real converter manufacturer makes his money. with their experience. it has nothing to do with peak anything. it has to do with keeping the motor loaded and locked down so it can accelerate. a converter puts the motor where it needs to be. The idea that gears will help accelerate you into your "happy zone" is 1950s technology and ideology as the conveter already puts you there. in the 1950s street cars needed bigger gearing to get them into that "happy zone" so it could spend the most time it could accelerating. obviously, most street cars are accelerating quicker at say 5000 to 6000+ when compared to idle to 5000 rpm. So back then (or in a case where someone doesnt understand converter technology they stick with stock junk) - they feel that gears will get them to that 5000 rpm range quicker. additionally, back then, intakes were not engineered to provide airflow throughout the rpm range. they were mostly peaky and rarely did a small motor have any torque or power down low. so they did whatever they could to get up to the rpm band quicker. Thus, the idea that gears make you faster.

But they dont with a proper modern setup. more gears only get you out of your power band quicker, which isnt a good thing. again, talking street car stuff and not dedicated race car stuff. the stuff you are talking about is a slow street car (no offense, just reality).

my car runs low 9s at mid 140+ in the 1/4 mile

my car runs high 5s at 117+ in the 1/8 mile

it goes to the 60' in 1.2x seconds

my car is over 3600 lbs raceweight

i run 3.73 gear with a 28" radial tire and more gear would only slow me down. also, converter slip should be no more than 5-7% (much less in race applications) and is easily measured at any given speed.

 

btw, no where did i talk about redline because it is also irrelevant.

 

another thing. good luck trying to leave consistently on the street or track with a 4.10 gear with the first gear ratio of a 4L60e. not only will you blast out of your power band but you will hit the tires hard with that big first gear. so you limit your top end significantly and hurt early performance.

lame.

 

another thing. good luck trying to leave consistently on the street or track with a 4.10 gear with the first gear ratio of a 4L60e. not only will you blast out of your power band but you will hit the tires hard with that big first gear. so you limit your top end significantly and hurt early performance.

lame.

 

Lol this is true, I've been trying to convince someone else that I work with of this fact as well

The "Gears make you faster" argument is true though in terms of acceleration in a fixed gear car like a manual. I run 4.30's all motor, then swap out to 3.90's when I run N20 to get more wheel speed. This is of course, on a 28" tire.

But we are talking about auto's so that's irrelevant lol.

 

**** got quiet up in here.