EL CAMINO 273 r&p replace

[bill cook]

What is the easiest way to kick up the rear ratio,been lookin for a 342-1 rear on long island NY for a long time no luck basically a bolt in ,i’ve Restored the 79 elky interior front end FB Trans,good wrench eng,brakes etc ,nice runner but that 273 rear just doesn’t make my day I have never rblt a rear ,so that’s new to me !any suggestions?

 

[ssn696]

I'll answer your question a different way. By the time you fix your rear axle the right way, you'll have $1500 in it, and it's still a 7.5. How about a 700-R4 overdrive transmission with the steep 3.06 first gear, and a powertrax locker you can drop into the differential yourself? This way, you have a 0.70 overdrive, and I think you'll like the combination with your existing 2.73 gears. You will need to modify your crossmember to move the mount back 2" and also you set up a non-computer lockup for it - click on my icon and there is a link on my profile on how to do this.

 

[bill cook]

I'll answer your question a different way. By the time you fix your rear axle the right way, you'll have $1500 in it, and it's still a 7.5. How about a 700-R4 overdrive transmission with the steep 3.06 first gear, and a powertrax locker you can drop into the differential yourself? This way, you have a 0.70 overdrive, and I think you'll like the combination with your existing 2.73 gears. You will need to modify your crossmember to move the mount back 2" and also you set up a non-computer lockup for it - click on my icon and there is a link on my profile on how to do this.

I have a 2004r

I'll answer your question a different way. By the time you fix your rear axle the right way, you'll have $1500 in it, and it's still a 7.5. How about a 700-R4 overdrive transmission with the steep 3.06 first gear, and a powertrax locker you can drop into the differential yourself? This way, you have a 0.70 overdrive, and I think you'll like the combination with your existing 2.73 gears. You will need to modify your crossmember to move the mount back 2" and also you set up a non-computer lockup for it - click on my icon and there is a link on my profile on how to do this.

i just had f&b install a 2004r transmission w/stall conv in oct of 18 for the od ,had a 200c ,which was goin ,also there’s a posi rear in the car now but 273,not lookin for a racer but would like more go off the line !

 

[bill cook]

I have a 2004r

i just had f&b install a 2004r transmission w/stall conv in oct of 18 for the od ,had a 200c ,which was goin ,also there’s a posi rear in the car now but 273,not lookin for a racer but would like more go off the line !

 

[64nailhead]

An OD with a 2.73 rear gear, even with 14" tires, will make OD almost non-useable. What size tires are you running?

If you can handle the swap, a couple of things to keep in mind. If you go higher numerically than 3.08, then you will need to change the center section as well because the the 3.08 and lower are considered a 2 series and higher is a 3 series. The gears are spaced differently depending on the series. There is a spacer that can be bought, but it's a bit too Rube Goldberg for me. From there you have to determine if you want a posi - most everyone does, but I'm confident you 2.73 is a peg leg. If you can live without a posi, then the price just got cut in half. Used open 3 series diffs are borderline free. From there your into a $150 for gears and $100 for a bearing kit if you can do the work yourself. If you can't you ought to expect $300-500 for a shop to complete it for you.

I understand that there isn't alot of love for a 7.5, but if they are put together correctly then they will withstand 300-350HP easily for many years.

 

[64nailhead]

We were posting at the same time. If your 2 series is a clutch style posi, then perhaps using the spacer would suffice.

 

[bill cook]

We were posting at the same time. If your 2 series is a clutch style posi, then perhaps using the spacer would suffice.

I haven’t opened the cover as of yet ! ,just spun the wheels to figure the ratio,I want to go 342 or 373 ,I know my od does not work properly the transmission guy told me that because of the stall conv !,but this guy bids racing trans ,ship all over the country and was recommended by a friend who races,he had a 323 ,but i’d Like to go up some ! As for the spacer ,I really don’t know what your referring too !

 

[64nailhead]

https://www.summitracing.com/parts/mgr-075050/overview/

OD doesn't work correctly? You should have 4 obvious gears and then the converter should lock in OD. I'd understand the converter not locking correctly, but OD will not be affected by a converter. What is your converter (who made it)?

 

[bill cook]

https://www.summitracing.com/parts/mgr-075050/overview/

OD doesn't work correctly? You should have 4 obvious gears and then the converter should lock in OD. I'd understand the converter not locking correctly, but OD will not be affected by a converter. What is your converter (who made it)?

I think u misunderstood me it works but ,I guess it freewheels because of the 1500 stall conv ,i can’t explain it’s not something that i’m Too familiar with,I wish I just had a 4 speed stick or a tremac ! ,the transmission guy said the rear needs to be lower for it all to work ! ,I guess ? Not my field of endever !

 

[pagrunt]

GM abused the use of OD transmissions back in the '80's. Why put a 2.41 in an OD car?