4L60E torque converter choices

[deja]

I am installing a stock '94 LT1 and 4L60E in my 280Z with a 3.54 rear gear. This car is quite a bit lighter than the Z28 the engine/transmission came out of . I was wondering about the torque converter. Is there a formula or software to choose the correct torque converter considering the car weight, rear gear, HP and use conditions (street, race)? I believe the stock Z28 torque converter is a 1200, not positive about that, don't have the shop manual here. On several Z28 message boards they talk about anywhere from 2500 - 3500 but that's in a Z28.

[A. G. Olphart]

To my knowledge, there is no formula or calculator. Guys on the turbobuick board are always asking what to run, and the answers vary with the engine's torque curve and the intended usage. A really high stall converter can feel strange on the street, with the engine winding from a stop before the car starts moving... the Z's light weight may mask this a bit. A 1200 RPM stall should be a dog off the line, but if it worked for the heavier Chevy, it will cause fewer problems in a Z. Costs nothing to see...

 

Opinion: for a mostly street car with a stock/mild cam, I'd stay on the low side of the range you gave. (Changing stall is all about letting the engine get into its' torque curve off the line).

 

Fortunately that trans has a lockup converter, so whatever stall you choose won't be a heat or mileage problem on the road.

 

 

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[deja]

Thanks, I'm scoping options at this point. I plan on running it stock for now.

 

 

To my knowledge, there is no formula or calculator. Guys on the turbobuick board are always asking what to run, and the answers vary with the engine's torque curve and the intended usage. A really high stall converter can feel strange on the street, with the engine winding from a stop before the car starts moving... the Z's light weight may mask this a bit. A 1200 RPM stall should be a dog off the line, but if it worked for the heavier Chevy, it will cause fewer problems in a Z. Costs nothing to see...

 

Opinion: for a mostly street car with a stock/mild cam, I'd stay on the low side of the range you gave. (Changing stall is all about letting the engine get into its' torque curve off the line).

 

Fortunately that trans has a lockup converter, so whatever stall you choose won't be a heat or mileage problem on the road.

 

 

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[icewtr]

The easy way to start to pick a cam is going by the recomended rpm range of your cam... if you look at most cam specs some say must use at least a 3000 stall .. your using a stock motor so the stock one should be fine .. but if you want to do any kind of drag racing or even leave the line a little harder try a 2000... to 2400 stall.. my z has a 2800 to 3200 stall and drives fine on the street and does not over heat the trans at all....

[Paz8]

Deja, my ZX which is heavier than your Z, has a carb 350 and an 700r4 auto which is almost the same as a 4L60E, and 3.54 rear gears, I run a convertor from a trans am firebird about 2000RPM stall. With your stock LT1 you don't need to worry about a bog off the line, you'll be more worried about keeping the car from going sideways. Use the convertor that came with the trans.it will work fine. You have a good combination for highway speeds, it will spin less than 2000 rpm at 60MPH.

[deja]

Since my car had a carbed 350 with a truck 5 speed transmission before I started this swap starting out hard and sideways is normal. Thats assuming it moved at all, most time it just sat there and spun. I don't know what the 1st gear ratio of that tranny was but lets just say granny gear!

Thanks for the input, we'll leve it stock for now and see how I like it. I don't plan on any drag racing, but I say that now, LOL.

 

 

 

With

Deja, my ZX which is heavier than your Z, has a carb 350 and an 700r4 auto which is almost the same as a 4L60E, and 3.54 rear gears, I run a convertor from a trans am firebird about 2000RPM stall. With your stock LT1 you don't need to worry about a bog off the line, you'll be more worried about keeping the car from going sideways. Use the convertor that came with the trans.it will work fine. You have a good combination for highway speeds, it will spin less than 2000 rpm at 60MPH.

[deja]

The easy way to start to pick a cam is going by the recomended rpm range of your cam... if you look at most cam specs some say must use at least a 3000 stall .. your using a stock motor so the stock one should be fine .. but if you want to do any kind of drag racing or even leave the line a little harder try a 2000... to 2400 stall.. my z has a 2800 to 3200 stall and drives fine on the street and does not over heat the trans at all....

 

Kind of what I thought. My long term plan is to build another engine with a bit more bite, I'll change the converter then. Thanks for the cam spec info.

[Paz8]

That 4L60E probably has a 3.08 low gear, which is plenty low enough, my ZX puts down about ten feet of rubber when it shifts into second gear with the shifter in drive position. Your going to like that combination it's fun to drive.