First, let me say:
AAAARUUUGHHH@@HH!!!**AAA!!!

- Okay, whew.

I have a '98 Z28, A4. The prev. owner installed 4.10s in the car....yes, 4.10s in an auto. Its truly insane, but almost not worth the headache.

I bought my car from a wholeseller, so what I know about the car is only what I've figured out. When I test drove it, I knew it had a gear, but wasn't sure what one...until I got it home, and on jack stands. I turned the rear wheels and counted how many times the drive shaft spun per one rotation of the wheel. It was just over 4 times = 4.10 gears.

The car is great for burn outs, but I cannot get a good launch for the life of me...that is only one problem. I'm in the middle of completely re-doing the whole suspension. This is helping...not as much as I'd like, but it is helping. (See sig for list of parts)

Here is my problem:
SHIFT POINTS

I cannot get a good feel of shifting for the life of me. I have a HPP, so I can change the shift points when I want. I went to vist my parents this weekend, and decided to try another combo with the shift points. I've owned the car for about a year...and I am continuously screwing with it. My father works for GM, so he called a buddy that works on the Trannys.

Depending on the gear combo, under light throttle they should be shifting from 18-22mph. My car stock with 4.10s was shifting at 10mph. I used the HPP, and raised it up +6 = the highest the HPP will let me, and now I am shifting 15-16mph. Still not even close.

Again:
AARIIGHGHHAARRGHH!!!!

This is what I've selected:
1-2 shift = +6
2-3 shift = +4
3-4 shift = +5

I don't have any shift frimness now.

I have also raised my Rev limiter to 6500 RPM's. I believe If I get on the car, and it down shifts into 2nd, it will bounce off the Rev Limiter....... Great So, I have to lose some of my mph so I won't rev it up to high, but now I will lose some of my traction that I gained with my mph increase. Its a lose-lose situation.

My 1-2 shift is also very firm. I believe there is recal for that, but I'm not sure. All I know is that I cannot find any help for this.

I've called Hypertech, but they were no help. They said they've installed 4.10s in a car and tested it, so they have no suggestions to offer me. I also called thunderracing.com, and asked the same question - they suggested I call Hypertech.

I'm pissed. I've had this car for a year+ and I can never get this right. I don't have the funds to go to a 3.73 - which I think would be better....I just want what I have to work.

....and for those who are wondering at 70mph my RPM's are around 2700, and at 80mph, I believe its around 3k. I usually get around 19-22mpg.

Any suggestions would be greatly appreciated, but please don't say: "You should have gotten a 6spd", or "Get a 3.73". If I wanted a 6spd, I would have gotten one. I also don't have the funds to do a gear swap right now....I just want what I have to work.

Milo.

------------------
CAR:
Silver '98 Camaro Z28 | Auto | Hard Top

ENGINE MODS:
HPP+ | 180* Thermostat | Fast Toys Ram Air | Whisper Lid | K&N Filter | MSD 8MM Wires | NGK55 Spark Plugs | '98 SS Single 3" Outlet Exhaust | ! Air Conditioning | ! Cruise Control

SUSPENSION MODS (all done in red):
4.10 Gears | MAC Panhard Rod | MAC Lower Control Arms | T Byrne Sub-Frame Connectors | Eibach Lowering Springs | KYB AGX 8 Way Adj. Shocks | BMR Relocation Brackets | BMR Strut Tower Brace

MISC. MODS:
! CAT | ! Front Steel Bumper | Clear Turn Signals | Front and Rear Blackouts.

 

hahaa...luv the topic.

sorry cant help u, i got a '00 M6 with 3.42 so sorry and good luck.

 

If your speedo is correct, then you have 3.73's. On 3.73's at 80mph you should be at 3000 RPM.

Try starting over. It usually helps when dealing with a problem..
Try going back to stock.. Then use the Hypertech to only change the gears.. Go for a drive.. Note what is different. 4.10's on autos arent wrong. I know many who have them. But they run 11's. hehe

I still think you have 3.73's though.

I would look more at the RPM s for shifting rather than the +#'s. I personally had my LT1 shifting in the 5800's.
For LS1 I would prolly bump that up to 6100-6200.

Perhaps that is why you are having such a rough time with this. If you dont know for sure the exact gearing then everything you try, if the gearing is wrong, will be bad. Correct? I would pop off the cover, drain the fluid and count teeth if it werent written on them.

Best way to know for sure, is to know for sure. Then you can troubleshoot better because you have some facts. I know that you counted the revolutions of the driveshaft and all. But I would personally count the teeth to know. What if you are assuming 4.10 and the fool before you has some one off gearing in there cause he was an excentric freak.

Also, on my car, the stock computer was programmed with 3.73 gears after they were installed so my speedo would read correctly without any Hypertech or other add ons.
I would look into getting that done.


------------------
Psycho Cabbage
2002 Camaro Z28
(6 sp) Bone stock
Webmaster for RaceHer.com
Check out the current polls and vote!
by the prìcking of my thumb, something wicked this way comes

-Traded in- 1995 Camaro Z28 (A4 (#6 I might add!),ES tranny mount and torque arm bushing,SLP CAI,ASP 34% Underdrive,Strange 3.73's (shredded Auburn),1LE alum driveshaft & intake elbow,Yokohamas AVS Intermediates,160-stat,MAF screen removed, HPP+(for shift points only),Borla Y-pipe, Flowmaster Force-II catback, Gutted Cat, Airlift Airbag, !TB Bypass, J&M LCA's, Bosch Platinums, Moroso BlueMax Wires, Free RamAir, Meziere Electric H2O pump, MAC 3point STB, BMR Panhard, SCR SFC's
Just installed:Nu-tek Heads (mild port) and Comp Cams 1.6RR's! New track and dyno #'s to follow!
best 13.44 @103.26
0-60ft 1.96
270 RWHP/296 RWTQ
0-60MPH 4.8sec
1987 Porsche 944S (waiting on LT1 mod)

[This message has been edited by psychocabbage (edited September 03, 2002).]

 

Here's what you do:

1. Put your car in 3rd gear (1:1, NOT OD)and find a steady speed to cruise, say 40mph. Note your rpm at that speed in that gear. Then find out your rear tire diameter and tell me this information, and I will tell you what gear ratio you have. I'm not calling you a liar, you are probably right but this is the way to know for sure. Math doesn't lie.

2. About the shift firmness, do what cabbage said and start from the beginning.

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1983 Monte Carlo, 307 Stroker, TH350, 3.73 10-Bolt - SOLD 8/19/02

Future F-Body Owner

 

I believe you do have 4:10s. I'm running about 2800 rpm at 80 mph with my 3:73s and 70 mph is just under 2500.But, you're using the wrong tool to fix something that ain't broke.

First, the HPP3 adjusts shift points at WOT only ... Don't worry about where it shifts at light throttle ... hell, depending upon how you drive, you can get it to shift pretty much anywhere between 10 and 25 mph for first.

Second, if you insist on adjusting your shift points, you need one of two criteria, preferably both, to base your adjustments on. One is dyno results that tell you what rpm your power band is in, the other is track times. The idea of adjusting your shift points, is to maximize your time in the power band for any given gear and therefor your 1/4 mile times.

Optimally between your gearing, tire height and shift points you want to be crossing the traps near the top of your power band. With a stock internal engine, 4:10s will probably push into your power band quicker than you need to be, For your best 1/4 mile times, you may actually want to consider backing off your shift points.

Last, what is your tire set up on the street? Even with Nittos, you're probably always going to be traction challenged on the street with the 4:10s.

Basically you have a track setup, that you're trying dial in with track tuning tools and expecting it to work well on the street. The issues that you are going through is the reason that 4:10s, for an A4 used primarily on the street, are not a good idea.

My recommendations - set all your shift points back to 0. Get some Nittos, if you don't already. Get a dyno to see where your power band is, then get to a track and start testing your shift points ... probably take about 9-15 passes to get it all worked out. If you can't get to a track, try it with a GTech or Tazzo.

And I know you don't want to hear this, but unless you have plans in the future to go to a cam that is going to be spinning you up in a higher RPM range, you need to consider going to 3:73s.

Good Luck

------------------
'01 Mystic Teal Z28
A4/3.73
Mods List Here

12.12/112.81/1.70 60'
325 rwhp/341 rwtq
www.MysticZ28.com

NorCal LS1/LT1

"To play it safe is not to play"

 

Oops! almost forgot:
SUSPENSION MODS (all done in red):
4.10 Gears - not a suspension mod
MAC Panhard Rod
MAC Lower Control Arms
T Byrne Sub-Frame Connectors
Eibach Lowering Springs
KYB AGX 8 Way Adj. Shocks
BMR Relocation Brackets
BMR Strut Tower Brace


Where is the poly torque arm bushing? You should get one..
Also an ES poly tranny mount as well.

And I always suggest that people get air bags. Put one in your right rear spring and preload and that should help traction as well. I would set mine at 21psi.

 

My problem is that under light throttle, it will shift at 14mph, but even under heavy throttle, it shifts at 15,16 tops!!

This was my thinking for 'upping the speed. I have no traction - none. I don't have nittos yet, just some BS Z-Rated tires on 16 inch rims. I was thinking that since I spin badly off the line and into 2nd, that if I could raise the speed as to when it shifts, that I could gain some traction in first, and then shift into 2nd no problem.

I wouldn't have an issue with no traction off the line, as long as I could get it back before it shifts. But, I still still spin all though 1st, and also into and most of 2nd. I haven't done anything to fix that - and I doubt I will with my tire/wheel combo. All I have done is mess up the shift points, and rev my engine out....

V6toZ28, you also say that the HPP only adjusts shift points at WOT only. I thought it was only shift firmness that did that..... With no programming I shift at 10mph, and with it I shift at 15mph. This is not done under WOT.

I do plan on adding a cam next year, or over the winter...FYI.


My Goal for the car is this:
Shift like a normal car on the street.
^^^ ^^ ^^ thats it!

I'd love to go to the track, but its not possible this year. Once I start working on the car, and make it a "stip" car, then I will focus on how to get it smoothed for the ¼ mile. But for now, I don't want to be jerked around in my car. I have big plans for this car.....it just takes time. I will also finsh up my suspension as soon as I can.

Milo.

 

like psycho cabbage said, count the teeth on the ring & pinion. if you want the car to hook, lowering it didn't do you any good, but an adjustable torque arm and lca relocaters will help greatly, and will work wonders if you raise the car back to stock.

 

remember also. your car won't have to go all the way to 18-22 mph to keep from falling on its face with 4.10 gears like it would with 2.73 or 3.23's, and hypertech knows this, which is probably why they won't let you raise it that high(emissions would be unneccesarily high to warrant shifting that high under part throttle) and you must remember that hypertech has to consider that since the HPP+ is 50 state legal.

 

This link will help figure out your gear ratio.

http://www.f-body.org/gears/

------------------
1998 Z28
A4 w/2.73's

 

this will help using the gear calculator

Automatic
1st gear = 3.06
2nd gear = 1.62
3rd gear = 1.0
4th gear = 0.7

 

My car has 3.73's in it. I have all the shift points set on eighter -2 or -3 so it will shift at about 5800. Don't worry about the mph, it doesn't really matter. My car will turn 6200 to 6400 rpm's like you said but it doesn't ran as fast turning it that hard.

In normal driveing it shifts to second as soon as it starts rolling almost. But you can exspect that with lower gears.

As for the spinning sounds like you need to practice your launches. I can spin through first and second if I don't launch right. I don't know how your launching, but have you tried rolling it out? Or build it up on the Brake, 1100 or 1200 if you don't have a converter, let your foot off the brack and ease down on the gas, don't stomp it. Try that and I think you will solve some of your spinning problems.

O yea spinning will make it shift early too.

------------------
'69camaro & '99 camaro Ls1 Z28, Pewter, spoiler kit, Borla, air box mods,K&N, egr mod, Mobil 1, HPP3, 160 Hypertech therostate,and N/X 20920 wet system

N/A 8.507 @ 84mph in 1/8
13.216 @ 104.557 in 1/4
60ft. - 2.001

NOS 125 shot 7.848 @ 93.280 1/8th
12.029 @ 118.095 1/4
on Goodyear GSC's

NOS 150 shot
7.404 @ 93.679 1/8th
11.597 @ 117.416 1/4
60 foot 1.674 on a slick

 

Okay, I did this last nite. In Drive, at 40mph, I am at ~ 2300 RPMs. I am pretty sure my tire diameter is 26.1/4 or 26.1/2 inches.... I don't have a way to measure it now. I did measure it about 4 months ago when I was playing with the HPP. I do know it is 26.something. They are the stock 16" rims and tires.

Milo.

 

If you know your P-Metric size that would work instead. 275/xx/xx. I tried it with a 26" tire and I know it isn't right. For you to have a 4.10 gear you would have to have a 24" tire.

Either that, or your speedo is wrong.

[This message has been edited by BlackHawk T/A (edited September 07, 2002).]

 

My G.F took the car to work today. She gets home at 4:00'ish. When she gets home, I'll take a look at the tire size.

Thank you very much for helping me out.

Milo.