64 Impala wagon ls1/4l60e rear end thoughts?

[zip]

I've just completed a ls1/4l60e swap,i'm a little disappointed with the performance of the line I realise its a heavy car but wondered if it may be down to the rear end and tyre combination it has a 3.36 diff and 235/70 r15 tyres has anybody any thoughts I'd be most grateful for any input
It had a zzz create motor and a 700r4 trans which i thought better but it only lasted a couple of days before the trans gave up thats why i swapped so never really had time to get a real feel for it.

[Craig@Bowler]

You could definitely improve on what you have to give you more off the line. Depending on which is easier for you to change, you could drop down to a 3.73 rear gear or a 26" tall tire( or both ) and make a difference you'll be able to notice and still not give up much on the OD side. Not sure what the optimum cruising RPMs your shooting for but if you are not in need of high speeds at low RPMs you could even go to a 4.10 range rear gear.

[zip]

Thanks Craig I bought my lock up kit from you when i swapped to the zzz/700r4
Ive considered the tyre size and was planning to try a lower size and see what happened,Id like to keep some kind of economy as I drive it everyday and over here in England petrol is £1.09 a litre!
Someone suggested it may be the torque converter as I imagine its still the stock one maybe a higher stall?

You could definitely improve on what you have to give you more off the line. Depending on which is easier for you to change, you could drop down to a 3.73 rear gear or a 26" tall tire( or both ) and make a difference you'll be able to notice and still not give up much on the OD side. Not sure what the optimum cruising RPMs your shooting for but if you are not in need of high speeds at low RPMs you could even go to a 4.10 range rear gear.

[Craig@Bowler]

True, if you have a stock 1800-2000 stall and bumped it to an HDHP 2200-2400 stall that would definitely give you a little more power to get going. I guess the main thing is to find out for sure what you're working with there.

[Skip Fix]

What rear end is it in now? The original 55-64 Chevy Pumpkin style 8.2 10 bolt? If you have much HP the 17 spline axles can let go. There are some guys that swap Dana 44 spider gears and clutch pack in to get a 30 spline axle that is stronger but the pinion is still only 17 spline. Start getting close to 400 HP and bad things happen to the stock rear end.

If you decide on a gear that is in the 4s(4.11s 4.56s) do NOT use a ring gear spacer plate. I ripped all the ring gear bolts out of one in my car on the street back in the 70s that ran 12s but it was a stick car.

[zip]

Yes its still the original rear end think I'll try a 3.73 if that doesn't satisfy me ill swap the convertor, the engine is stock except for headers and flowmaster system and a filter so if the axles do give up i'll just have to upgrade the rear end.

QUOTE=Skip Fix;1197272]What rear end is it in now? The original 55-64 Chevy Pumpkin style 8.2 10 bolt? If you have much HP the 17 spline axles can let go. There are some guys that swap Dana 44 spider gears and clutch pack in to get a 30 spline axle that is stronger but the pinion is still only 17 spline. Start getting close to 400 HP and bad things happen to the stock rear end.

If you decide on a gear that is in the 4s(4.11s 4.56s) do NOT use a ring gear spacer plate. I ripped all the ring gear bolts out of one in my car on the street back in the 70s that ran 12s but it was a stick car.[/QUOTE]