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Dana44-4.09 gears

M

mjsrun

Guest
Has anyone changed their gears to above 3:90 and found speedo and drive gears. They are not available from GM for my 4:09
The only other supplier is Lingenfelter for a big
price way above $3-$5 a gear.
Has anybody any knowledge of a better way to go
(besides electronic applications) for C4's with a ZF-S6-40 6-speed?
 
Viper dealers have 4-10s that are supposed to fit in the Dana 44(rear that comes with 6speed)
 
I'm doing a swap on the gears next week on my Dana 36. I found a few places that had the right speedo gears to match the new gear ratio. They all wanted about $50.
The guy who is doing the work for me found someone who had the right speedo gears for $20.
When I go down there Monday I'll ask him and let you know Tuesday night if you still haven't found any.
Graham
 
trrgod
I have researched the Dodge Viper and the 4:10 may be an aftermarket axle. The dealer suggested that an axle outside of a 3:07 stock would only hamper the emissions tests.????. I am still looking though. Doesn't mean there isn't a 4:10 application. Just won't find one at Dodge.

vms4evr
Your info would be helpful. I would be interested in hearing about your Dana36 install. I am wondering how much of a challenge getting speedo and drive gears was.
 
I have no idea what the dealer is talking about??????? I've read on other forums that the ring and pinion(4-10s) for the Viper fit the C4 Corvette. It is my understanding that both have a Dana 44 rear carrier and that the Viper gears fit right in. What this has to do with "hammering the smog test" I can't comment on. Sounds bogus to me. Maybe he as putting you on. Anyway, it would make no difference which company made the gears, all results would be the same. Do Vipers pass the smog test with 4-10 gears? (I think 4-10s are the stock setup for Vipers) You need to do more checking on this--go to another Viper dealer and ask a knowledgeable parts guy. Maybe call a couple of Vette experts and ask if Viper parts work. Someone will have to install the gears anyway so maybe that someone will have this answer.
 
Trrgod,
Don't misunderstand me here. I have installed Dana44 4:09 gears already. The thing I am finding difficult in getting is the small speedo drive gear for the ZF transmission. The stock gear is a 15 or 17 tooth. GM does not make the 13 tooth gear for the calibration correction of a 4:09
The Viper uses a stock Borg and Warner trans.
I have yet to find out if this transmission or variations have a 13 tooth gear. If there is it will have to be the same I.D. or close for a correct fit inside the rear housing on the main shaft of the ZF trans. Fat chance.

Smog test seems a little shaky, definitely.
Can you see a viper with another 30% hp. A 4:10 would definitely assist in that aspect of things.
That is if a 3:07 gear is used such as Chrysler describes it in the specs.
 
mjsrun said:
trrgod
vms4evr
Your info would be helpful. I would be interested in hearing about your Dana36 install. I am wondering how much of a challenge getting speedo and drive gears was.

trrgod,
getting the gears was not a problem at all. came right from GM. here is what we put in:
$8.60 - GM 25513050 - 43 tooth speedo gear
$5.46 - GM 8642620 - 15 tooth drive gear for 700R4

This is to correct speed going from 2.59 to 3.54 in the Dana 36.
The speed is accurate within about 3mph.

I have another post in here on "Rear Gear Change" which I'm updating on the results of the gear change.

Graham
 
Now I see what's going on. I thought you were talking about the rear end gears when you were refering to the gears needed to correct the speedo. I'm sorry.
 
Graham,
If you get a chance to discuss the use of a 13 tooth drive gear for speedo. I would appreciate it
Will check out the "rear gear change" article of yours.

trrgod,
No problem. I appreciate the interest.

Racer78
At this point since the 6speed is user friendly. I can now use the 6th gear. Before the change the vette labored in 6th at 1600rpm at 70mph. Now at 70 I'm at 2100rpm. Off the line is much better. Still have problems with those GT Mustangs until the higher speeds. The newer cars seem to have gears put in them to give them high speed early on and then at 70 there is no go.
Probably using some version of a 4:56 or thereabouts to give them the pep.
 
Racer78,
Right! Only difference it's no longer a stock 350cu/in.
It is modified to a 355 now. (bored .030 over).
With the 4:09 axle it creates about 20% more HP along with the other things I have done.
Mine is put together a little like a Z06 package.
Chose not to go to a 383 stroker.
 
mjsrun,
ok i found a few guys that emailed me some info about what you're stuck with here. whether it's 4.09, 4.10, 4.11 it's pretty much the same deal.
The driven gear you can get from GM. I think the one you need is only ever listed for an 84. It appears to be the only time they ever used a 45-tooth gear. It should be Lt. Blue, part # 25513052. Call the dealer it should be about $10.
Now the 13-tooth drive gear. Well that is the problem. You unfortunately were right in the beginning. Lingenfelter had them specially made for them because GM never offered one. So you bite the bullet and pay Lingenfelter. Or get the programming unit and set the speed yourself.
If you use the programming method you can get it almost perfect from what I understand. If you use the setup you are talking about you'll be off by up to 3 mph.
Right now I'm off by 2 mph using GM parts when compared speed to my wife's new car. Hers could be off but before I changed gears we agreed that we were going the same speeds from 35-75. Now I read 2 mph faster.
Graham
 
VMS4EVR,
I ENDED UP BUYING THE LINGENFELTER GEAR.
IT WOULD COST ME OVER $100 FOR THE ELECTRONIC UNIT AND ABOUT THE SAME FOR THE GEAR.
I JUST THINK THE ELECTRONICS THING IS JUST ANOTHER THING THAT CAN GO BAD WITH THE ELECT.
THANKS FOR THE INPUT.

RACER78,
IN ANSWER TO YOUR QUESTION.
THE CAM IS A COMP CAM WITH .51 LIFT WHICH JUST ABOUT MAXES OUT THE CAPABILITY OF THIS 2 BOLT MAIN BLOCK.
THE HEADS WERE MACHINED AND HEAVIER DUTY SPRINGS AND NEW VALVES WERE INSTALLED TO WITHSTAND THE GREATER PRESSURES.
I HAVE MOLY/TITANIUM PISTONS AS WELL. THEY WORK WONDERFULLY COMPARED TO STOCK PISTONS.
THE THROTTLE BODY WAS REBUILT AS WELL. WONDER IF I SHOULD HAVE GONE BIGGER WITH A 52 OR 53 CC.
EVENTUALLY, I MAY BE ABLE TO AFFORD THE TOP HALF WITH NEW PLENUM AND INTAKE. JUST ANOTHER 2G'S
THE CAR HAS A REAL THROATY SOUND FROM THE FLOWMASTER AND RANDOM CATBACK SETUP
I HAVEN'T DONE ANYTHING TO THE INJECTORS. JUST KEEP THE FILTER CLEAN ALONG WITH USE TEXACO PREMIUM AND NO ADDITIVES TO CLEAN FUEL INJECTORS. THAT DOES THING IN REALLY BAD.
MY WORK WAS DONE BY A FORMER CORVETTE RACE DRIVER RICK STARK ENTERPRISES IN KIRKLAND, WASHINGTON. VERY KNOWLEDGEABLE AND THE COSTS ARE MUCH LESS THAN WHAT YOU WOULD EXPECT FOR A COMPLETE REBUILT.

I COULD ALWAYS FIND A WAY TO IMPROVE THIS CAR. AT LEAST IT DOES NOT DEPRECIATE SUCH AS MOST VEHICLES. A WINNER I MUST SAY.

MARK
 
RACER78,
THE HYDRAULIC ROLLER COMP CAM DURATION IS RATED AT INTAKE 230 EXH. 244 WITH .51 DEG. OF LIFT AS I MENTIONED
IT IS THE #290HR-12
THE CAM SHOULD OR COULD BE USED WITH LARGER PLENUM, INTAKE AND RUNNERS. STILL SOME ROOM FOR GROWTH.

NOT BEING AN EXPERT ON THESE THINGS I AM ONLY READING THE SPECS AND AM HAPPY TO LEARN MORE AS THE DAYS GO ON.
NOBODY HAS EXPLAINED THE DURATION BUT I AM SURE THIS IS WHAT IS THE IMPRESSIVE THING ABOUT THIS REBUILD.
I AM AT ABOUT 11-12 DEG BTDC. OR THEREABOUTS. KIND OF DIFFICULT TO SET WITHOUT A COMPUTER SCOPE.
TRIED WITH A STANDARD TIMING LIGHT AND IT IS STILL WORK.
MARK
 
mjsrun said:
Racer78,
Right! Only difference it's no longer a stock 350cu/in.
It is modified to a 355 now. (bored .030 over).
With the 4:09 axle it creates about 20% more HP along with the other things I have done.
Mine is put together a little like a Z06 package.
Chose not to go to a 383 stroker.

How does a changing the rear end gears produce more RWHP? Sorry for the dumb question, but I don't drag race my GTS (I like the twisties). I can tell you if you want to increase RWHP without a huge amount of mods, is go to a very lightweight carbon fiber drive shaft. Viper's driveline loss is estimated at 10%, whereas most cars have a 20% loss from FW to RWHP.

Vipers use a Super Dana 44 with 3.07 gears in it. After market places like Unitrax sell replacement gears and hard core half-shafts for Vipers. I will tell you one thing, that for seat of your pants feel, it's hard to beat gears. In Vipers, the common upgrade is to 3.55's. The reason is because Vipers with anything higher never hook up their tires. They literally smoke rubber down 3/4's of the track. Everyon ethat I have heard that went to the 4.09's has regretted it.

By the way, the serious racers go to a Dana 60 because it is a more robust rear end. The 44 is pretty flimsy when you race it with mods. The Viper does use a Borg-Warner (Tremac) T-56 transmission. It is the exact same transmission that the C5's use. This is a pretty strong transmission, but if you are going to do a lot of racing you should consider a sequential like a Quaife or the hardcore Lenco.

Just my $.02 from a Viper perspective.

Take care and be safe.

Brad
 
Viper 10,
When you think about it. Seems funny that GM would use a ZF in their C4's. The mass flywheel
and other parts are Borg-Warner. I wonder why BW's were not used. Could have been that their weren't any 6 speeds at that time by BW.
It is a pretty sure thing about the Viper being boosted by about 25% with the 4:09. 700 HP + or equivalent would be smokin..
It was described to me that the combined addition of all parts that maximize efficiency increase HP. May not refer to just engine HP.
I have never heard of Corvette's using a carbon fiber drive shaft. I was just reading my manual about drive shaft and U-joint replacement. Seems that the shaft has to run within .006 and .011 TIR. when it is replaced. Suppose that if each shaft was running out the tolerances would just make an exageration and an additional imbalance with the shaft and the half shafts.
I may check mine when the weather is less wet
Mark
 

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