ESS tuning impressions-

[mpower03]

Originally Posted by Burt Reynolds

Hi, I think both the 4.10 and the 3.91 are a major improvement over stock gearing...neither is mild. I would say 3.91 is good if you want to preserve some revs and save a little gas. 4.10 is a take no prisoner approach to tearing up the asphalt. I bought mine from a top end tuning shop here in Chicago area called fall-line motorsports. I did a core swap vs. gear swap/rebuild. You can get the Dinan 3.91 for around 2500.00 plus 500.00 labor. The 4.10 is about the same price. On dry pavement with my snow tires (read lower traction), I get the traction light in the first 3 gears if I step on it too much. It does pull like a freight train.

BTW, if you are looking to get more out of your tune, I would suggest you read up on the RPI scoop and BMC filter combo. This relatively cheap mod can make your tune go to work pretty hard. Good luck.

hey with only 2500 miles on the car would i have to rebuild if i just get a ring and pinion? How usable is the car with 4.10, because my car is a daily driver but i just want to make it come to life a little more. Is first gear pointless?

[Burt Reynolds]

Not a tranny expert so I would not want to mislead. My car is my daily driver and the 4.10 is just fine. You shift more, and my mpg is down 0.5 mpg before my tune. It directionally is back to stock mpg now that I have the ESS tune but I am only on my second tank of gas though. My tuning shop advises people get the 4.10 over te 3.91 but I believe they are both major improvements over stock. Ask Epbrown what he thinks about his 3.91 (I believe he loves it). I am sure he and I will have a better way to compare this spring if he shows up for some local meets. I would like to let him drive mine and maybe drive his to see if there is real difference :P

[mpower03]

Originally Posted by Burt Reynolds

Not a tranny expert so I would not want to mislead. My car is my daily driver and the 4.10 is just fine. You shift more, and my mpg is down 0.5 mpg before my tune. It directionally is back to stock mpg now that I have the ESS tune but I am only on my second tank of gas though. My tuning shop advises people get the 4.10 over te 3.91 but I believe they are both major improvements over stock. Ask Epbrown what he thinks about his 3.91 (I believe he loves it). I am sure he and I will have a better way to compare this spring if he shows up for some local meets. I would like to let him drive mine and maybe drive his to see if there is real difference :P

what does rebuild consist of, and why would you rebuild?

[Z4MCJJ]

I am not sure what the re-built entails, but you can get the rack and pinion set from http://www.diffsonline.com/

Price: $875 a set, and $1070 a set with REM polishing.

Maybe polishing is worth the extra dough??

[mpower03]

Originally Posted by Z4MCJJ

I am not sure what the re-built entails, but you can get the rack and pinion set from http://www.diffsonline.com/

Price: $875 a set, and $1070 a set with REM polishing.

Maybe polishing is worth the extra dough??

yeah, 900 plus install isn't that bad for what your getting, but like the dinan 2500 plus i don't think it would be worth it. Thats why i want to know on a car that is pretty much around break in period miles would i have to rebuild?

[O-cha]

Out of curiosity what are you guys being charged for a diff swap?

[Z4MCJJ]

Originally Posted by O-cha

Out of curiosity what are you guys being charged for a diff swap?

I haven't looked into it yet....the shop I have used in the past only want to put Dinan parts in my car....so their quote was like $4000 if I am not mistaken...and that was for the Dinan polished ring and pinion...

I am not a mechanic, but for me it may be worth saving about $3000 if I can do it myself...

[epbrown]

Originally Posted by mpower03

yeah, 900 plus install isn't that bad for what your getting, but like the dinan 2500 plus i don't think it would be worth it. Thats why i want to know on a car that is pretty much around break in period miles would i have to rebuild?

I think you're misunderstanding what happens. If you buy the parts from diffsonline - the gears and ring and pinion - a shop will have to disassemble your differential, remove the original parts, install the new ones, and re-build it.

With the Dinan upgrade, what they essentially do is send you or the shop a differential that's already been rebuilt with the new parts; when your old one comes to them, they rebuild it, shelve it, and wait for someone to order one.

Break-in opinions differ. The new gears will need to mesh, you can expect some filing of metal, and you need a break-in service to change the fluid and remove the initial bits of metal that come off. Some people feel with polished gears like BR got, you don't need to re-do the break-in because the polished gears won't shed any metal filings.

O-cha - iirc, I was charged 5 hours of shop time for the swap.

[mpower03]

i was thinking that when you rebuild it you have to buy all new parts. so your saying rebuild is just put it back together?

[epbrown]

Originally Posted by mpower03

i was thinking that when you rebuild it you have to buy all new parts. so your saying rebuild is just put it back together?

Correct.

As Burt indicated, I like the mod. Imo, it's the best bang-for-the-buck mod you can do to the Z4M.

[mpower03]

looks like i will be next for a review on it because i am sending out my DME tomorrow.

[Burt Reynolds]

You will love it...especially the mid range punch. You have headers too so you will be ahead of me until next week

[mpower03]

got my ess software back i will write a review once i get the 100 miles.

[Burt Reynolds]

Surely you have driven 100 miles by now

[nmulax]

That's what I'm thinking too.

Took Todd's advice and put a few gallons of 100 octane in the other night (then filled the rest of the tank with 91). Going to try this for a few tanks and see how it goes.

[mpower03]

not really. lol even though this is a daily driver, i work within 5 miles from my house, go to school with 2 from my house.and since i got it back that is all i really have driven.i am at about 30 right now. lol.. ill get it done by the weekend. ill give a little update.

So after i go to install my dme, i see that i still have my service engine soon light ( still had it after i drove 15 miles. . I contacted roman and he said that i had to get my codes cleared. So i was going to do that this weekend, then all of the sudden today my light disappears! don't know what happened there but know i don't have to go get it cleared. I have about another 15 miles w/o light, so hopefully it will stay no light. Anyway about the tune.
As soon as i back out of the garage i noticed the difference. Your probably going to laugh, but i did. lol the throttle response is SOOOO much better now. The car is a lot smoother now. Before, you used to get a punch after 3500 rpms, now i feel you get it a lot sooner. Also the low and mid range is imroved really well. When i first got in the car i lost the auto up for the windows, but after a while they came back. I also noticed my exhaust tone is different. Before when i had my headers installed it was a lot raspier. I may be hearing things now but it definetly sounds different. This could be because i haven't driven the car in 3 days and don't remeber what it used to sound like, but i am pleased. I haven't driven the car hard yet, as i want to make sure everything is okay with the tune first, but i will go for a few runs this weekend. As of now i am very happy with the tune, and i feel that this is the way the car should have came from the factory. Also, sport mode is actually useable now. Before it was either all throttle or no throttle, but now it is a lot better.

[Z4MCJJ]

Originally Posted by nmulax

That's what I'm thinking too.

Took Todd's advice and put a few gallons of 100 octane in the other night (then filled the rest of the tank with 91). Going to try this for a few tanks and see how it goes.

I have been running 95 octane --> 100/91 mix for a week or so and this seems to give the car a bit more power. I am doing this to allow the DME to tune to this level as I am tracking at Firebird this weekend.

[F360C]

Originally Posted by mpower03

not really. lol even though this is a daily driver, i work within 5 miles from my house, go to school with 2 from my house.and since i got it back that is all i really have driven.i am at about 30 right now. lol.. ill get it done by the weekend. ill give a little update.

So after i go to install my dme, i see that i still have my service engine soon light ( still had it after i drove 15 miles. . I contacted roman and he said that i had to get my codes cleared. So i was going to do that this weekend, then all of the sudden today my light disappears! don't know what happened there but know i don't have to go get it cleared. I have about another 15 miles w/o light, so hopefully it will stay no light. Anyway about the tune.
As soon as i back out of the garage i noticed the difference. Your probably going to laugh, but i did. lol the throttle response is SOOOO much better now. The car is a lot smoother now. Before, you used to get a punch after 3500 rpms, now i feel you get it a lot sooner. Also the low and mid range is imroved really well. When i first got in the car i lost the auto up for the windows, but after a while they came back. I also noticed my exhaust tone is different. Before when i had my headers installed it was a lot raspier. I may be hearing things now but it definetly sounds different. This could be because i haven't driven the car in 3 days and don't remeber what it used to sound like, but i am pleased. I haven't driven the car hard yet, as i want to make sure everything is okay with the tune first, but i will go for a few runs this weekend. As of now i am very happy with the tune, and i feel that this is the way the car should have came from the factory. Also, sport mode is actually useable now. Before it was either all throttle or no throttle, but now it is a lot better.

Congrats on the software! Does you car have some surging (thats the best word I can use to describe it) between 3100-3800ish? I put the headers on and while I have no check engine lights it seems like the car is pulling timing until it hit 4000rpm then it takes off like a bat out of hell.

O-Cha or anybody else out there have some ideas? Is this normal or is this all in my head? I thought it might have been a leak so I went and re tightened all the nuts holding the headers on and I used all OEM gaskets. The only thing I can think that is causing this, if it isn't normal, is something I did with the front pre-cat 02 sensor. I didn't like how the top of the front pre-cat 02 sensor contacted the the rear header just slightly so I went and had the bung moved to the left a bit so there were no contact issues. I used one of the caps that came with the headers to cap the old bung. Could this be causing weird flow issues in the header and making the 02 sensor act funny? I only get the surge in 3rd gear usually when I try a ful throttle pull from 3,000rpm and maybe alittle in second gear from the same rpm. If I do a full throttle run in first no problems at all. I think this might all just be in my head but any advice anybody can give would be nice.

[mpower03]

Originally Posted by F360C

Congrats on the software! Does you car have some surging (thats the best word I can use to describe it) between 3100-3800ish? I put the headers on and while I have no check engine lights it seems like the car is pulling timing until it hit 4000rpm then it takes off like a bat out of hell.

O-Cha or anybody else out there have some ideas? Is this normal or is this all in my head? I thought it might have been a leak so I went and re tightened all the nuts holding the headers on and I used all OEM gaskets. The only thing I can think that is causing this, if it isn't normal, is something I did with the front pre-cat 02 sensor. I didn't like how the top of the front pre-cat 02 sensor contacted the the rear header just slightly so I went and had the bung moved to the left a bit so there were no contact issues. I used one of the caps that came with the headers to cap the old bung. Could this be causing weird flow issues in the header and making the 02 sensor act funny? I only get the surge in 3rd gear usually when I try a ful throttle pull from 3,000rpm and maybe alittle in second gear from the same rpm. If I do a full throttle run in first no problems at all. I think this might all just be in my head but any advice anybody can give would be nice.

like a surge of power??

[Burt Reynolds]

My DME is going through the 100 mile adjustement all over again I had my Active Autowerke headers installed today and the car is definitely in the process of adjusting to this major change. At first the idol was a little rough but as I ran the car a little, the idol smoothed out. I put about 25 miles on the way home and it is already faster. Now all I have do is drive it some more and get a little more power from my tune! I will post a review on the headers in a seperate thread after I drive with them a little more.

[F360C]

Originally Posted by mpower03

like a surge of power??

Yea a surge of power.... well it feels sometimes like it pulls a little power when i am at full throttle in 3rd between 3,200-3,800rpm then i get a huge rush of power after 3,800rpm

[Burt Reynolds]

Does it do it now with the software? Mine is still going through the 100 mile adaptation but I have not noticed any surging at all. I wll updatelater. I wonder if it coul be related to the pulley? You might check it on a dyno and get some readings....hmmm.