herders

Hey All,

I have not decided 100% on the engine but it will be a 350 SBC at the very least.

What are the benefits to a manual transmission vs. an automatic transmission.

what is the difference with the 700R4, TH350,TH400, 4L80E and benefits of?

If I were to get a manual transmission what would be the best for the buck, for a high performance street car?

I see Borg-Warner often what is so special about that brand?
what are the differences for the different models t-5, t-56?

I have looked some of the specs but I do not quite understand what they all mean...

Then after all that I could only presume that a different differential would add to my confusion. What do the different gear ratios mean, what is best for what application?

Would buying a used transmission and rebuilding it be worth the time and effort?

Any assistance is appreciated.

Thanks

Paul

vetteoz

iTrader: (13)

what is the difference and benefits of

700R4; 4 spd ,has overdrive top gear , saves fuel
TH350,;stronger but only has 3 gears , no O/d
TH400;very strong (1st choice of drag racers ) but only has 3 gears , no O/d
4L80E; same as TH400 but needs a special computer to operate it

Edit , my mistake
4L80E is 4 spd overdrive version of a TH400

Choice of trans depends on what you need , fuel economy for street use /cruising or strength for racing ?????

eseibel67

If car is used as a fun driving toy, manual is the way to go hands down. Auto is better for a daily driver, or if you are drag racing.

If you decide to go with a manual, you want a T56. With a 350 SBC, you'll want to get one out of a 93-97 F body. Forget the T5 unless the car already came with it, the power level it modest, and you drive it really nice.

AlkyIROC

Th 4L80E has the same 3 gear ratios as the TH400 but also has an OD gear. It's also a computer controlled transmission and is the heaviest out of all of them tipping the scales at around 250 pounds.

Gear ratios are torque multiplication. The low first gear of the 700R4 added with a deep gear in the diff like 4.56 means you'll have enough torque to pull a stump out of the ground but the gear would also max out in rpm in about 20 feet at WOT. A close ratio gear ratio means as you shift through the gears, the ratio is close together so that the rpms don't drop out of the powerband as each gear is selected.

Your transmission choice depends on how you want to run the vehicle. Everyone now wants something with OD gears. They add nothing to performance. All the OD gears are for is to drop the engine rpm down during highway driving to reduce the amount of fuel burned by the engine. Up until the early 80's, millions of vehicles ran back and forth across the country without an overdrive so it's not something that you absolutely need to have.

All those transmissions in your list have different abilities. They all work fine but some do better in different applications.

herders

Thanks for all the info....

Paul

paul_huryk

Depends on the trans, but the 700R4 has a really deep rpm drop from 1st to 2nd due to the 3.06 and 1.63 gearing. The TH350 and 400 have much better gear spreads, but no OD gears - plus they need different driveshafts and trans crossmembers. The 4L80E has advantages with it's strength, OD, and gear spreads, but as Alky mentioned, it is a heavy one.

As for manual transmissions, the T5 has a good gear spread and will hold decent power with a good clutch if you don't abuse it too much. A lot of people here on the board have gone to the T56 or other non 3rd gen OEM or aftermarket transmissions for strength and compatability reasons.

transamws6

here's a example of ratio...I had 700r4 nd 3:23 gears in diff on my 92 car was great on take off nd awsome on highway..as a daily driver .. wen I switched to a t56 6 speed I had to get a 3:73 because the 3:23 gears didn't give me good take off...


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T/Atime

i love the idea of having a t56 in a car that never came with it. it has that exotic feel to it.

but at the same time about 14 years ago i sold my 86z28 t5... i could not stand it.

my good friend had a 87 gta with a 700r4 and loved the idea of just hitting the gas and pulling like hell. while my 86 was a fun car to drive. it just did a poor job going 0-60. the t-5 just left me with a bad taste im my mouth, also needed a rebuild like every year or so.

11 years ago i picked up my 91 and rebuilt the 700r4 with a shift kit and really enjoyed it. it will not slip and shifts very firm at wot. at this point the trans runs well but could use some attention.

my question is for the boys out there running a built auto w/stall, gears govenor set just right and a shifter too. do you ever think i wish i had a t56.....? automatics will shift perfect everytime and provide years of reliability.

but a t56 sounds like a lot of fun, im very proud of my car at this point. the direction it has taken over the past few years from gear choice to suspension work, its become a well ballanced street car.

ps i want a 6spd

Homer23

An automatic is better as a daily driver if you are a boring driver.

Manuals are more fun to drive because the driver has more direct control of the vehicle. Automatics are easier, of course.

Often, with fairly major transmission problems, a manual just has problems with a clutch. An automatic can have more issues, which can cost much more than a clutch kit with a manual.

Borg-Warner is the company that made the T5 and T-56 manual transmissions. Each one was used in more than 5 applications which would make it more notable or special. The T5 is a 5 speed transmission first produced in 1982 and the T-56 is a six speed manual transmission first produced in 1992. The T-56 is based off of the T5, hence the name. A T5 with 6 gears.

The T5 cannot handle very much torque at all, that's why the 3rd gen camaros and firebirds with 350 v8s only came with automatics. I wouldn't expect it to be able to handle 310 lb/fts or more of torque.

The T-56 in the 94-02 F-body can handle 450 lb/ft of torque which is much more desirable for any type of performance application. It is also a double overdrive transmission which gives your car better PERFORMANCE, in fuel economy anyways.

You may be okay with the differential or rear end you have for now.

Gear ratios multiply torque. The ratios in the transmissions are the ones you won't have to worry about too much since it's a street car. The final ratio is the one in the differential that you may or may not change. A 4.1 ratio is very short and is best for racing applications. A 2.73 ratio is the tallest ratio I have seen and that's great for cruising. You will want to be in the middle somewhere between 3.23 and 3.73 but you have to drive your car after your engine and transmission setup is done first.

If you are loaded, get a brand new transmission. You will have a warranty and not have to worry about poor maintenance. Otherwise, get a used one and rebuild it when it breaks.

Richmond make 5 and 6 speed manual transmissions if you wanted something a little different.

Oh, and read a few car magazines. Chevy High Performance and some other good ones will give you some knowledge and good ideas of your car setup.

Phenom-1

I think for daily driving in traffic a 3rd gen with a 350sbc would work best with a 700r4, you got overdrive for fuel economy and no hasseling with gears at every red light & green light.

For Mostly Highway driving with no traffic and for fun the 350sbc with a T-56 for good spirited driving and to make sure that you have a manual that can take the torque of a 350 because most T-5s break when you upgrade the original 305 to a 350 in an original T-5 car, it can't handle the torque in excess of 300lbs for too long, some owners have even broken the T-5 with the stock TPI 305, so T-56 just to be on the safe side and not have to worry about it. Match it with good gears like 3.23 or 3.42 or 3.73 and your good to go.

oamhmad

iTrader: (1)

I have a SBC 350 with a t56 behind it and love it even for every day driving. The engine has enough torque to pull through high gears at low rpm so when I'm feeling lazy I can easily minimize gear shifts by starting out in 2nd, skipping 3rd and 4rth, and going straight to fifth at 35-40 mph.