I posted to a couple of old threads about tranny rebuilds this morning, but thought I would extend this out to those not subscribed to those threads.

I thought I would stop ignoiring my 2nd gear pop out and fix it, while tearing the tranny apart found that my 2, 3 and 5 gears are in serious need of replacement. I remember reading about the 5 and 6 gear lube/cooling issues last year but it didnt directly pertain to me so...

My knowledgable and trusty tech basically says that any increase in power significantly heats up the tranny, especially when driving triple speed limit speeds while in Mexico, the GT2 has increased lube to the 5/6 gears but not the turbo, it's just a matter of time.

Since I am rebuilding my tranny, I am considering a cooler, circ pump and seriously thinking about re-gearing to match the Z06 0- 60 in 1st, a quicker 60-130 and slight higher top speed, I will definitely do steel synchos while I am there.

Does anyone else have any real world experience. advice ? Anything you want to keep quiet for whatever reason, please PM or number and we cna discuss.

//Anders

 

Wondering why you think the z06 has better gearing for 60-130? What do you mean 'shift point" 3rd gear redline? I thought our cars were the best cars geared for 60-130? I learned actually shifting my car higher yielded a better 60-130, now that I have a little higher redline and make more power up top.

 

I need to edit that, I like the Z06 1st gear, if I remember correctly, they can hit 60. I think the TT 60-130 is very good, with a little different ratios, it can be even better.

 

I think the TT 1st gear is OK with a higher redline, not great mind you, but better. I think the overall gearing is better on the tt than z06's stock. 5th and 6th is VERY long on the z06 and doesn't really pull, whereas my 5th and 6th pulls like 3rd and 4th... optimum for 60-130's

 

0-60 in FIRST gear? If memory serves me correctly, I think I top out at 40-41 mph in first. I would imagine re gearing to allow for an additional 20 mph in first would cause you to lose some speed right off the line? What are the other consequences of making a change like that? Sorry if my questions are remedial, my knowledge base with gear ratios has been limited to threads I've lurked. Good luck with the rebuild too!

 

If you decide to stay stock, I have a brand new 1st / 2nd gearset you can have for a very good price, as well as slightly used 3rd, 4th and 5th.

 

Strath, pm me your info, might be an option.

As for the Z06 gearing, my understanding is the latest Z06 can get damn to 60 in first gear, one of the reasons it's so damn fast 0-60. I think with stock hp/tq it wouldn't be a good idea, but 600-650 I should have enough power and I would only be interested in match g first gear acceleration and mph range.

 

I had DAS in Philly do my 2nd gear. I went with stock gears (not steel) due to their advice....steel would make too much noise day to day. I replaced all the gears just to be safe. Once you are in there, the parts were no more labor....wish I had done the tranny cooler now, but at the time I did research and was told by two tuners that for DE it was overkill....(others here would disagree with this...and I suspect it is ok...but I was also told it could OVER COOL the tranny....). I don't remember who told me that, but it made sense at the time.

Check the long thread on the 2nd gear pop-out issue (used to be a sticky). In it, I outlined the things done and the contacts I made.

Key is the machining of the fork for 2nd gear....to prevent problems.

If anything, 1st is too short stock in my mind....but I am sure there was a reason for that.

Good luck.

Jeff

 

I think you should ask Stanely at G box. He has many options for first gear and if memory serves me correctly they also have a first gear that allows you to reach 60 before shifting into second. I have a question for you, when you stated that you 2nd, 3rd and 5th gears were need of serious replacement, did you mean the gears or the synchos? My transmission is at G box and what they have found beside some structural damage was that many of my sychos where horribly damaged. The damage limited my ability to shift into certain gears.... I hope this helps.
Robert

 

You already know my opinion on this, but I'd go the thermostatic switch or heat exchanger route for cooling. Al Norton has installed a very economical heat exchanger inline with his water lines in the driveshaft tunnel and has wired in a pump... The only thing I'd add would be the strayers to the nose cone and in the back of the trans.

As to going steel vs. stock OEM gears, I'd go steel... They do make a slight bit more noise, but you won't hear it with an aftermarket exhaust. You'll also want to discuss syncros and forks and see what options there are for these boxes... Rob actually describes some of the issues I've had with my box. It sometimes is hard for me to find a gear unless I heel/toe. Rob, what kind of structural damage to your box?

Also, I know that some claim it's overkill, but the GT2 and GT3 live just fine as street cars with these units... It's an added $1500-2000 for a cooler installed by a shop, if the trans is being opened up anyway... I think it, along with the GT2 Slave upgrade are smart money spent.

Mike

 

My plan is to add a cooler in time.....would love to add one that DID NOT need the tranny to be dropped somehow....labor is not free.... Anyone know if this is possible?


Jeff

 

Al Norton has installed one that uses drain and fill ports only and he's going to test it and report back soon. His uses a MOCAL heat exchanger and pump, all parts sourced thru the normal online race car fab sources... I'm waiting on his report... Pulling hot fluid from the nose and circulating it thru the exchanger may be enough for DE types like us, Jeff! Having just returned from south Florida where every day was HOT HOT HOT, I'd want one, especially if I were DE-ing down there!

Stay tuned!
Mike

 

I've had my car back frorm having the trans rebuilt for a couple days, my first impressions, although I am on a low power breakin in, are that the longer 1,2, and 3rd gears are much better spaced and much easier to drive in traffic with. What is noteworthy is that the transmission cooler (aka heat exchanger) helps heat the motor up noticeably quicker, of course this is while driving, idling wont make a difference. I have also sent the temp guage move just a tad to the right, if my temp wasnt usually dead on 180, I doubt I would notice.

The UMW lightweight flywheel is a bit to get used to, mostly becuase of the significantly reduced power from the break in file. It's getting better after a couple hundred miles. The UMW intake kit hasn't had much change yet while on the break in file, but I can definitely hear a change in the airflow and can easily hear the K24/26's spooling but again I am limited to .1-.2 bar through break in.

After the break in miles, I'll get some real world acceleration tests and be able to comment on the clutch, gears and the LSD a bit more, my initial guess is there will be significant change.

Kevin/UMW rocks and I'm completely stoked and looking forward to the fun!

More to follow.

 

Chris, PIA to do the break-in isn't it...did kevin give you a break-in flash? Also have you had your tune adjusted for the LWFW? Look forward to your updates....fall is in the air...time to do a mountain cruise...

 

Brother, you aint kidding!

Yep, Kevin gave me the flash breakin file, its like a prison sentance. I think it does have the adjustment, I sent him an email saying I would be ready for the next file tomorrow night or Saturday morning, in hopes I would get it before he knocks off for the weekend.

I know a few of us that would be up for a fall mountain cruise, last one we did was allot of fun.