Thinking About 4.10's

[Ross]

After long thought and much reading of this board, I'm thinking that this year I need to upgrade my exhaust (probably DR setup due to cost and ease of install, although I would love the Kook's) and get some 4.10's. I know that there are no absolutes on adding mods, but about how much quarter mile difference in time should I see with 4.10's? I know there are variables, but a rough approximation is OK. I haven't run on a track yet, so I can't tell you what my ET's are now. Just kind of looking for some general info.

[Smokie]

Ross, something that might be helpful until you recieve the responses you are looking for. When you look at members profiles you can see the posted E/T's and on most sig's you can view the mods. You can see my time, I have stock gears, the PCM was reflashed. I hope this helps some.

[BillyGman]

You might already know this since I've mentioned it 3 or 4 times on this board in the past 8 or 9 months, but incase you didn't catch it before, I'm probably the only one here who installed the 4.10 gears BEFORE performing any other mods including the chip. And w/the 4.10 gears alone there was absolutely no difference at all in the way the car accelerated, nor in my ET's. And I know for certain what gears were put in there, because I installed them myself, and even counted the teeth on the ring and on the pinion gears and did the math seconds before the installation. Furthermore, even though the acceleration didn't increase at all, my gas mileage went down by 2 MPG (from 17MPG city, to 15 MPG). So I was getting the worst of both worlds. Poorer gas mileage, along w/no improvement in acceleration!!!!

But once I installed Dennis Reinhart's chip, I then gained a .50 reduction in my ET's. I believe that performing the chip install alone, would've given me a reduction in the ET's, but I don't think that it would've been an entire .50 seconds w/the chip alone. Therefore my conclusion has been that the factory stock computer settings will not allow the car to take advantage of the a different gear ratio, until you chip it. So I think that the ET reduction that I obtained after the chip installation was due to a combination of the new gears and the chip.

So I cannot say how much of that .50 sec ET reduction was due to the gear change, and how much of it was due to the DR chip. If I had to guess then I'd have to simply put it in the middle by saying that half was due to one, and the other half was the other. But that's simply a guess.

If you know how much of an ET reduction you obtained w/the chip alone that you have installed on your car, then maybe that will give you some kind of idea about the possible additional ET reduction that you might obtain w/the gears. I must admit that it would be interesting to find out provided you know what your ET's are know, and what they were BEFORE the chip installation. And BTW, all of them would have to be taken in similar temperatures. (atleast within 5 degrees F. I would say).

[Ross]

Interesting, Billy. I remember your posts. I have a chip, and I know I would have to have it reprogrammed after I changed gears. If your "seat of the pants" calculation is close, and I could gain about a .25 ET reduction, then it's probably worth it. I know that the better exhaust should give me at least that much of a reduction, too.

[Paul T. Casey]

Billy, I got .5 sec with chip, plugs, pullies, and stat, no gear change. That figure is in an 1/8 mile track. I'll let you know the 1/4 mile difference soon. I'm thinking the pulleys and plugs with the chip may account for such a big difference.

[BillyGman]

Let me know what you find Paul.......that would be nice if you had some before and after 1/4 mile times instead of 1/8 ile though since the 1/4 mile is the standard in drag racing and the measure that most of us use to judge all out acceleration.

Ross, the .25 sec reduction is just a guess like I've stated, but the the .50 sec ET reduction is NOT simply a "seat of the pants" guess. It is infact arrived at via ET comparisants.

[Paul T. Casey]

Fortunatly, Atlanta gave me the 1/8 times and mph, so I did have something to compare to. I'll be headed back there mid April for the 1/4 differences. I almost wish I did the mods 1 at a time to see actual gains. I also may try out a homemade ram air set up down there.

[woaface]

Billy, do you think that because you didn't reprogram, the car treated the 4.10's like 3.55s?

[cyclone03]

I still DO NOT HAVE GEARS and I have not run my current combo at the track but I did run 15.36 stock then 14.86 with noting but a DR reflash in my computer!So there's .5 sec et reduction with only a reflash.
Something to think about with gears at the track SOMETIMES the car gets hard to hook up with the gear change so you loose the et gain due to lack of traction.

[BillyGman]

Some answers I just don't have for you guys since I was very surprised myself when the car didn't move any differently at all w/the gear change alone. I was shocked, frustrated, and turned to people on this board to help me out as well as to some of my friends, and nobody on this board was able to give me a direct answer as to why. And I mean NOBODY.

There were some guys here who really tried to help and gave me some suggestions(the best one being that this car is just so heavy that one mod all by itself short of supercharging will not do anything to get it moving a whole lot better), and then there are those who just plain argued w/me and ridiculed me by saying everything short of coming right out and calling me a liar(and some of them came pretty close to that!! I don't need to mention names either, they know who they are:rolleyes: ).

But after having to get into a major debate on here w/some of the guys that I was looking to for help, as well as hearing some good suggestions from others, the bottom line was, and still is, that when all was said and done, and when all the smoke cleared from all the arguing that I had to endure, NOBODY could give me anything more than a guess at best, as to why my car just didn't move any faster w/the gear change all by itself. And most didn't even do that.

And w/how great my car moves now, and the excellent ET's it turns, all I can guess is that what I've stated before in my previous post: that these modern day computer controlled cars will just not respond to a gear change unless the computer is tapped into by one means or another. That is my only guess, and yes, it is a guess. Nobody has been able to provide a definative answer including myself.

I have absolutely no ill motive for stating that. It's simply the way it is. As far as Cyclone's question about the gears causing the tires to break loose, NO that isn't it at all. W/the 4.10 gears I still couldn't get the tires to break loose at all even on the street w/out using the brake, let alone on the track where they have all that sticky VHT traction compound.

Even now w/the 4.56 gears my car hooks up perfectly well at the track w/the street tires. My 0-60' times were 1.8 seconds at the track, and that was w/out even brake torqing it!! I simply used one foot, and just hammered the gas pedal down when I saw the green light. Because of that, I think I can probably get an even better ET out of my car just the way it is since my technique off the line could use some more practice and improvement.

I hope some of what I've written here helps, but weather it does or doesn't, these are simply the facts. Take it or leave it friends. :)

The only other thing that i want to point out to you guys is to pay attention to the temperatures at the track each time you go, and compare them w/other times that you have went in the past, or the times you'll go in the future. I've seen a .3 sec differnce in my ET's between an 80 degree day and a 40 degree day.

So if you say that you have experienced a .50 sec reduction in your ET from a computer reflash alone, just make sure that 3 tenths of that half second difference wasn't merely due to a 20 or 30 degree temperature difference at the track.

[TooManyFords]

All I can say is that Billy'e experience with the gear swap was different than mine. I clearly got a big reduction in 1320's with no other change than switching from 3.55 to 4.30's.

http://john.frieltek.com/TooManyFords/Marauder/GTimer/img/GTimer1.jpg

Run #2 was done just after having the PCM flashed by Dennis.
Run #3 was done just after having the gears swapped.

I don't have a baseline run of my MM stock because I didn't have the G-Timer till after the PCM flash. I should go find a stock on around here and plug it in to see. Maybe at MV II...

John

[duhtroll]

John -

Deery's has a few on the lot. Borrow one of theirs for a test drive, hook up the timing cpu, floor it a few times, and then say "nope - too fast to drive safely!"

They had a couple used 03s last I saw, and one silver 04.

-A

[BillyGman]

All I can say is that Billy'e experience with the gear swap was different than mine. I clearly got a big reduction in 1320's with no other change than switching from 3.55 to 4.30's.


Run #2 was done just after having the PCM flashed by Dennis.
Run #3 was done just after having the gears swapped.

John

John, that's some very valuable info that you've shared but i see a contradiction in your above statements, and that contradictions simply backs up what I've previosly stated. You first state that you got a change from the gears alone, but the point i was making was that I installed the 4.10's BEFORE the chip or anything else, and the fact is that you had the computer re-flashed BEFORE you performed the gear change.

my point was that unless you do something to change the stock computer settings, i don't believe that any gear change wil ever make a difference. And I think that this has a lot to do w/why your #3 run yielded so much of an increase. it's because you had already previosly had the re-flash done to your car's computer as run #2 represents. :)

[Paul T. Casey]

IMHO, the single biggest performance adder we can do is to reflash the factory "fuel economy" settings into something that makes more scientific sense for creating and applying power. With the stock fuel management and shifting settings, the gear changes and fuel metering will still take place at the same points on the tach (the one the computer watches.) It seems to me that any slight gains at the start of a run with only gears, i.e. faster engine spin-up to shift points may not exceed the top end speed loss of the lower gears. Granted, our cars are heavy and should benefit from the lower gears, but without the re-flash/chip, it still wants to shift way before peak power is made.

[BillyGman]

true, but when it comes to these computer controlled cars, and gear changes, i think that there'ssomething else going on here, because w/the 4.10's that I had at first, i wasn't even getting any better 0-60 MPH time recordings until after I had the chip in, and that only involved the one shift point from 1st to 2nd gear. So because the transmission is in 1st gear for most of that time (until about 40 MPH I think) then the gearing should stil make a difference by itself, unless there's something else besides the shift points that the computer is holding back on in it's stock configurstion. perhaps it has something to do w/the torque management settings for the transmission since the computer also controls all of that stuff.

This stuff just gets pretty complex. But I will aslo sy, as I have stated before in other threads, that for me the biggest acceleration gain that I made out of the mods I've performed so far on theis car is the Stallion Torque converter (a .70 second reduction in the ET) and second place goes to the Kooks headers and exhaust package(a .55 sec reduction in the ET).

[Paul T. Casey]

Timing is probably tied to rpm's and torque load. Probably doesn't want to advance in stock configuration, impossible to tell without a serious upgrade in my neural mapping. I wonder who sells this. :rolleyes:

[BillyGman]

It sounds like you're more into that aspect of this than I am. "Marauderer" might be able to point you in the right direction w/that, cuz he seems to be very much into stuff like that.

[Paul T. Casey]

He a brain surgeon?

[BillyGman]

LOL...I just looked at your previous post again. you threw me off w/that "Neural mapping" term!! I thought you were talking about some kinda chip burning software stuff.........nevermind.

[bigslim]

Mine is going to Lidio this week for a chip and 410. I will post some info as soon as get it back.

[HwyCruiser]

Someone with a Stage 1 with the SCT hand-held should be able to easily prove the theory of 4.10's vs 4.10's w/ the tune if they have a stock baseline with the 3.55 gears.

I'm running the stock program with 4.10's right now due to sending back the SCT to DR for a checkup. I was out riding around today and other than the flabby shifting, I still "feel" that the car is quicker off the line and through the gears than with the 3.55's. It'll still scrub the tires from a standstill without brake standing. Didn't even think about it with the 3.55's. I've only put on about 800 miles since the gear swap.

Try it at the track? I don't even know where it is so obviously I don't have a baseline. It only takes about 5 minutes to switch tunes, so someone out there should be able to give it a whirl.

My $0.02.

- JD

[BillyGman]

That's an idea, although the tire spin itself can be tricky to read slso since these tires seem to break loose easier once they begin to wear.

[CRUZTAKER]

I'm running the stock program with 4.10's right now due to sending back the SCT to DR for a checkup......

- JD
I did this this for a month while my chip was in "temporary summer high school helper" 'lost in mail or somewhere limbo' last summer.

Not cool racing. I hit the rev limiter every time I WOT. Not a cool feeling.

[TAF]

Ross,

Go with the 4.10s...you won't be sorry...:up:

[SouLRioT]

I figure this would be a good thread to add this too, hope it doesnt derail it. But with the gear swap, how much of a gas mileage drop are you guys seeing with the 4.10's, I have yet to install my kit.

[BillyGman]

for me it was a reduction of 2MPG with the 4.10's and another 2 MPG with the 4.56's.

[SouLRioT]

was this with or without your chip, or both?

[BillyGman]

both with and w/out. Even when the initial installation of the 4.10 gears was done which I peformed w/out installing a chip, the MPG dropped by 2MPG despite the fact that the car didn't show any improvement in acceleration at all. That's another reason why I was just so surprised about it.

[SouLRioT]

thank you for your help Billy, has everyone else had this same result???

[sailsmen]

A gear change with out changing when the PCM instructs the trans to shift will results in shifts that are either too early or too late ( as in hit the rev limiter) depending on wether the gears are taller or shorter.

The PCM has to initiate the shift before it is required due to the lag time that the trans actually shifts after it is given the command to shift by the PCM. A 4:10 will need the shift command to initiate sooner than a 3:55.

As respects the 4:10 @highway speeds I noticed at most a .5 mpg loss.

[merc406]

Opec just said to Hell with us, expect way higher gas prices this summer. :argue: :shot: :bigcry:

[SouLRioT]

Sailsman, i've got the chip and gears but havent installed them yet. Do you by chance know your city MPG?

[sailsmen]

Sailsman, i've got the chip and gears but havent installed them yet. Do you by chance know your city MPG?

I think it's 15-16, but city dirving is so subject to variables.

I think it's better to compare Interstate driving which for me averaging 70 is 20mpg, (note to average 70 you have to go 80 to make up for the gas/rest stops).

[bigslim]

I said the hell with OPEC and had my chip and 410 installed today. Makes a world of difference. Picked up about 250 rpms at 80 mph.

[jgc61sr2002]

bigslim - Congrats way to go. :up: Enjoy :D

[SouLRioT]

yeah i hear you about opec, but with the cash flow spent on the parts, i need to conserve it as much as i can.