Dana 36 1985 C4 Corvette Auto. Thin Or Thick Gears On 3.54

2 series corvette differential carriers (you have a 2.73:1 rear gear)
generally require a thicker gear to run a 3.54:1 gear set)

yes reading links does help avoid problems,
when selecting differential parts,
ALWAYS take the time and effort to talk directly too ,
the part or component manufactures tech dept if you have questions
https://www.yukongear.com/partslist.aspx?SearchMode=Diff&Type=Dana&DiffID=124&DiffName=Dana+36&CatID=35&CatName=Ring+&+Pinion+Sets

https://us1.campaign-archive.com/?u=0b4217cf231c53e35d69f8fff&id=be6677f7bc

https://www.usgear.com/products/ring-and-pinion/dana-36-3-54-corvette-2-73-down

http://garage.grumpysperformance.com/index.php?threads/under-car-safety.26/

https://www.drivetrainshop.com/Dana_36_ICA_s/86.htm

https://www.richmondgear.com/auto-parts-product/?crt_differentialcasedesign=dana+36

https://www.jegs.com/i/Richmond-Gear/836/49-0143-1/10002/-1

http://garage.grumpysperformance.com/index.php?threads/1993-c4-gear-change-2-59-to-3-54.10659/

https://www.corvettemods.com/C4-Cor...ing-and-Pinion-Gear-Set--Dana-36_p_14606.html

http://www.ronsmachiningservice.net...a-36-ica-3-73-ring-and-pinion-yukon-gear-set/

https://www.zip-corvette.com/84-96-3-54-dana-36-ring-pinion-2-series-carrier.html

http://garage.grumpysperformance.com/index.php?threads/dana-36-vs-dana-44.163/#post-7245

https://www.pirate4x4.com/articles/tech/billavista/Gear_Setup

https://www.strangeengineering.net/...rvette-3-73-for-3-54-and-higher-carrier.html/


This is from Graham who frequents this sight often. I think something like this should be a part of this sight if possible (are you listening Rob) it is that well presented.

Again, I did not put this together, but I wish I had it is that good.

"Ok, seeing as how this comes up a bit with "What is the speed/rpm with a given gear?" Here's the answers I got when doing the math for my gear change.

Assumption: Tire Diameter = 25.7in (275x40/17), Drive Ratio is 1.0, Overdrive Ratio is 0.7 (this is for an auto of course). 5400rpm is max with factory PROM/Chip.

In Drive (ratio is 1.0)

Ratio 2.59 3.54 3.75

MPH RPM RPM RPM
----- ------ ------ ------
45 1524 2083 2206
55 1862 2545 2696
65 2201 3008 3187
75 2540 3471 3677
85 2878 3934 4167
95 3217 4397 4658
105 3555 4860 5148
115 3894 5322
125 4233
135 4571
145 4910
155 5249
165

In Overdrive (Ratio is 0.7)

Ratio 2.59 3.54 3.75

MPH RPM RPM RPM
----- ------ ------ ------
45 1067 1458 1544
55 1304 1782 1888
65 1541 2106 2231
75 1778 2430 2574
85 2015 2754 2917
95 2252 3078 3260
105 2489 3402 3604
115 2726 3726 3947
125 2963 4050 4290
135 3200 4374 4633
145 3437 4698 4976
155 3674 5022 5319
165 3911 5346


The formula works as follows:

For Drive (ratio 1.0)
RPM = ((RE Ratio * MPH) / Tire Diameter) * 336

For Overdrive (ratio 0.7)
RPM = (((RE Ratio * MPH) / Tire Diameter) * 336) * OD Ratio

So if you want to calculate different rear gears or final drive ratios just plug it into the formula. Or use the tools on this website or many others.

Graham
 
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Thanks for fast reply and the links.
I Sendt a mail to summitracing they didn't know.
In the prosess of ordering some parts for my project, want to pick up some parts from ther warehouse in Georgia.
Going on vacation to Orlando 20 August for 3 weeks.
Making the atlanta excusion as a little road tripp.

Looking forward to some funn at New smyrna speedway and mayBe drive some laps at Daytona again.
 
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btw buy new differential gears, not used ones, those are a Risky buy,
if these gears were run with poorly set up tooth contact pattern,
you will inherit noisy gears, no matter what you do.
have an experienced shop or mechanic set up the rear gears,
if they are not correctly installed they will be ruined or at least noisy
in fact your differential can differ just enough, dimensionally,
to cause new issues to come up with previously run gears from a similar differential,
that worked ok in that differential

https://www.jegs.com/i/JEGS/555/816...MIp7rxrdmf6AIVh4bACh0AwgOjEAQYASABEgLDi_D_BwE

https://www.jegs.com/i/Proform/778/66516/10002/-1

the chances are very good that a different ring & pinion gear set will require a different shim stack height.
yes a 10 bolt is different from a 12 bolt but there's several similarities in the gear swap process.

http://garage.grumpysperformance.com/index.php?threads/differential-rebuild.257/#post-308





 
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