JMcCabeUSMC

I知 rebuilding my engine soon. 1985 stock L98 coupe auto 4. I知 going for around 400-450hp so I wanna get a higher gear ratio while still having drivability I知 not running a track. Can I swap in 3.07 gears in the 2.73 rear end or do I need a whole new rear end? I知 proficient with engine work but I致e never messed with a diff. I know my limits and if I feel like I can稚 do it right when the time comes I値l have it done at a shop but I just wanna know if it can be done.

WVZR-1

You mention 'higher' but I believe you're talking 'higher numerically' - higher is generally a lower numerical number. The differential is different for a 2.73 vs 3.07 so the most practical way and likely least expensive would be to buy a known 3.07 complete if that's your desired ratio. There's also thick gears so you could potentially do 3.54 or 3.73 using your differential that's there now. You need to actually confirm what's there. You've a lot going on and I believe you just rethink the entire project.

RWDsmoke

The auto trans cars came with a Dana 36. With 400-450 hp you would be better off investing your money in a Dana 44.

JMcCabeUSMC

I do mean numerically higher. I just want more kick off the line since the additional hp should make up for top speed lost with the numerically higher gear ratio. I checked and I have the Dana 36 2.73. Been looking into swapping in 3.54 gears because I don稚 have the money for a new rear end they went up to around 700 on eBay. The kit for the thick 3.54 swap for the Dana 36 is 400 from Strange. I知 thinking that痴 what I want to do.

WVZR-1

I would post a WTB D36 3.54 here on the CF and see what might surface. There's likely someone with a built that either isn't happy or has moved on to a D44 for the car. Be sure to mention 'where you're located'. Maybe if not already built maybe they have the gears (bought wrong or whatever) and you could buy what they have. If you're using yours you need a 'thick' gear kit but if you're buying an already built you would want to now also if it's a 'thin or thick' build.

Where are you actually located?

dentalfloss

Personally cost and less work I would just swap out the carrier with 307 as they are more available for sale and for less money,

JMcCabeUSMC

I found the thick gear set D36 3.54 new for $400. Just the ring and pinion. I知 in North Carolina in the camp lejeune area