z28cmr83

Hey everyone, its been a while since I have visited ThirdGen, but I am finally getting everything together to restore my 84 Z28 that I have held on to for 15 years. I have a bran new LS3 in the driveway and I am trying to figure out which transmission to hook it up to. What is the difference between drivability/performance on these 2 transmissions with their respective gear ratios of:

TUET11009
2.66 / 1.78 / 1.30 / 1.00 /.80 / .63

TUET11012
2.97 / 2.10 / 1.46 / 1.00 / .74 / .50

I am coming from the stock T-5. I am assuming I will be running a 3.73 rear, but I'm open to suggestions if anyone can provide some info on what I can expect from these combinations. My goal for this car is modern drivability, I will never be at the track, but I want to retain the Camaro spirit.

rgauder

iTrader: (1)

The closer ratios would be more fun for a protouring type build.

Jeremy85

I agree, somewhat. But the wider ratio spread is closer to what GM used behind the LS3, and if you choose the wide, you're copying the drivetrain and gearing HotRod used on their orange 2nd-gen Camaro build about 2 years ago. They went with the ERod LS3, the wide-ratio T56 Magnum, and a 3.70:1 rear. You can Google their follow-up article for how it worked out. The deeper first is better in parking lots, and will launch better on drag radials. You have enough axle gear to pull that sixth without lugging.

jmd

iTrader: (4)

Go test drive an LS3 Camaro. If you like the 1-4, go 2.97.

Then test drive something with the 2.66.

Neither is a bad set of ratios. If you were going to the drag strip then I would say 2.66. A casual cruiser is great with 2.97.

All that interrelated to the rear gear.

And, don't get too tied up in 6th gear ratio. In the TR 6060 line, including T56 magnum, each can be changed.

Jeremy85

Depending on your driving circumstances, better to be turning an extra hundred RPM all the time with the 0.63 sixth than always downshifting out of the 0.50 sixth. Fifth is just as easy to change.

malc1080

which transmission did you end up going with? im looking at them both on summit racing the TUET-11009 being cheaper $3,195.00 vs the TUET-11012 for $3,379.99.

Will this transmission fit easily in our 3rd gen camaros? I heard you just had to cut the floor shifter 2in back is that correct?

daferris

iTrader: (8)

Tremec now has a Magnum F that does not require you to cut the floor. Think it's available in both ratios

malc1080

oh wow your absolutely right! Thank you for that info. It’s on summit racing it’s the “magnum-f manual transmissions TUET16362” for $3,395.00.

GeneralDisorder

iTrader: (1)

Interesting - can the Magnum F accept a normal gen 1 sbc bell housing? This would make a T5 replacement a lot easier......

GD

sofakingdom

iTrader: (1)

The closer ratio and a higher-number rear gear is where the "fun factor" is at.

Factory choices for things like that (*cough*LS3*cough*) AREN'T designed to maximize "fun" in all cases. They are intended to minimize emissions, minimize warranty expense, minimize emissions, appeal to the widest possible audience, minimize emissions, give the best available fuel mileage, minimize emissions, ... oh did I forget to mention, EMISSIONS?? Quoting "that's what the factory used" isn't really altogether applicable to a hot-rodder build.

Having had a 83 L69 Z28 with the lame stock 3.73 ratio and a LT1 T-56 with 1st - 3rd ratios similar to the closer ones up there, I'd say, 3.73 isn't enough gear. It's pretty much about the bare minimum. It felt almost like the OE T-5 taking off in 2nd instead of 1st. 4.10s would be much better.

malc1080

gen 1? You’re not pairing it to an ls1?

GeneralDisorder

iTrader: (1)

The OP is using an LS3....... I wouldn't be. I rather like the old school myself. My $200 Vortec puts out 400 HP and revs to 6500 so I don't really see the need on my daily.

I'm just curious if you could mate this to a gen 1 with the right bell housing and clutch components.... it says it won't work with an external slave which is a bummer but I'm sure I could work around that.

GD

Thirdgen89GTA

iTrader: (5)

What axle ratio do you have right now in the car? Are you planning on changing it to a shorter gear?

Personally, I'd go the close ratio, and STILL choose a shorter gear. I tried to post this nicely, but TGO doesn't support the BBCode for Tables, or straight up code correctly. Code works, but the formatting is junk.

Go to this Google Doc, make a copy of it for your use. Then you can edit the drop down for Gearset, Final Drive, and Tire/Rim combo. It'll calculate your MPH ever 100rpm. I've already set it to the Magnum TUET11009, 3.42s, and a 245/50/16 tire.

Bill's Transmission Gears vs MPH Calculator

daferris

iTrader: (8)

You have to use the QuickTime bellhousing and a LS style push clutch.

GeneralDisorder

iTrader: (1)

I assume flywheel's for that clutch mated to a gen 1 are readily available? Sounds like it will work then! I may go this route on my 91 Formula.

GD

jmd

iTrader: (4)

Mating an LS1 F-body T56 or T56 Magnum to a Gen I or II SBC is the same deal since their maindrive (input) is the same and the 8 bolt pattern is the same.

LS1 F-body T56 bellhousing + the Centerforce spacer is one way.
QuickTime specific scattershield for this swap is another way.
The 4 bolt to 8-bolt adapter plate (used with the late 90s "aftermarket T56") and third gen or other Muncie pattern bell is another way.

You gotta get the pilot bearing right. etc. etc. etc.