Hello! I have some noob questions about a manual transmission swap, so if you could help me to get started. (my english is not perfect, so sorry about that)

I have a 89' RS camaro, It's got GMPP 350HO motor, 600cfm carb, TCI Street fighter transmission and lots of other aftermarket goodies. Last week I installed new shocks and went for a test drive and then suddenly the transmission just started to act like it was in neutral. Not a single gear worked any more.

After pulling the pan out and noticing that it was full of shiny metal chips. I decided to start to look for a manual transmission. I'm done with auto transmissions. Never really liked it. I bought the TCI brand new 4 years ago. So it's very low mileage, since I can only drive at summer months here in Finland. About 3000-4000 miles/year. ..but I do drive it very hard, I mean burnouts everywhere, full throttle shifts constantly :-D But then again this engine is not very powerful so it should've survived longer.

Back to the point.. The new transmission is going to be TREMEC T56 MAGNUM I really don't want to start to swap out transmissions every other year. So is this the transmission I want?

Do I need to re-balance the whole engine since it's externally balanced with a flex plate? or can I just balance the new fly-wheel to match the old flex plate?

I can fabricate a new crossmember, but there's an aftermarket crossmembers out there for t56, but for example the Spohn one says that "NOT T56 MAGNUM" why is that?

At this stage of research, I'm very confused about a lot of things, do I need a new drive shaft? What bellhousing to use? What would be the best clutch? I have no idea what parts fit and dont.

Also is 3.23 rear end gears going to make it hard to get going from a complete stop?

Thanks!

 

I assume your engine has a one piece rear main seal (RMS). You can find any flywheel for it, which should be "neutral" balanced to go on the 350.

This bolts to SBC/BBC and an LS-style T56, including the Magnum. It's a little pricy, but is a scattershield, too.

The "LS7" clutch has gotten good reviews. But, any traditional "push clutch" should work.

Read this for more info.

3.23 x 2.66 = 8.6:1 .. your rear and T56 first gear.
3.42 x 2.95 = 10:1 ... T5 with 3.42 performance rear gear.
3.8 x 2.66 = 10:1 ... T56 with rear gear to be similar to T5. Since 3.80 is not an available ratio, you will either have to go down a little to 3.73, up a little to 3.90 (if available), or up a little more to 4.10.

 

Thank you for your help. But...I have now tried to research the web and I found this text from the 350 HO manual:

"Like all small block V-8 engines produced since 1986, the 350HO Deluxe engine has a 3.00” diameter flywheel flange bolt pattern. Small block V-8 engines produced from 1958 through 1985 had a 3.58” diameter flywheel flange bolt pattern. This change in bolt circle diameter was made to accommodate a leak-resistant one-piece rear main seal. Due to revisions in the crankshaft design, a 350HO Deluxe engine must have a counter-weighted flywheel (or flexplate) for proper balance."

So I do need a counter-weighted flywheel.

Edit: okay now that I have made some more reading. This seems to be commonly misunderstood thing.

 

Yeah, this topic can make people talk in circles. The flywheel is not "0 balanced". Instead, it does have a counterweight cast into it, like ALL standard 1 piece RMS flywheels. A standard flywheel for 1 piece RMS engine/crank/flywheel will work just fine.

 

Okay, I have now collected some parts to my cart at Summit Racing. I have two possible clutches, so I'm asking if anyone has any experience with these? Is there a better choice? (probably is if willing to pay)

That bellhousing costs mad money.. but there seems to be no other choice?

I also need a hydraulic throwout bearing, pedals, and then... I would like to put a new speedometer in my car so I need to figure how to get that to work. The reason for that is because I need to race against my dad and his car goes 155 miles per hour. It would be nice to see how fast I'm going.

 

I could be wrong but there are some special considerations when using a LS based t56 vs a LT based T56. I just wish I knew what they were.

 

Yeah.. I'll probably need a different lenght driveshaft and need to modify/custom torque arm.

 

Save yourself some trouble and find a wrecked T56 LT1 car.


The stock T56 should hold the power you're making fine.

That way you can use the pedals, bellhousing and transmission from the wrecked car.

Add hydraulics, and a new clutch and a cross member from Hawks or somewhere and be good to go.

 

"Save yourself some trouble and find a wrecked T56 LT1 car"

Whats the chances of THAT in Finland? Just say'n

 

Actually I probably could find one. There are lots of lt1's here. But I have not even started to make power yet.

 

The LT1 trans can be just as strong. I would probably find and rebuild one if you can. I think the LS input shaft is longer and has a different spline count where the LT will bolt right up with the proper flywheel. With the LT you should be able to use the factory drive shaft.

 

New or modifying the drive shaft/torque arm is not a problem.

But what would be the downside of a longer input shaft and different spline count?

I remember one saying that the TCI Streetfighter can take lots of power.

 

If we are truly talking 155 MPH here , and not KPH , your gonna need a turbo , nitrous , or both to top 160 MPH ! (which is what you must do to beat a 155 MPH car)


The only way I see a smallblock powered , non boosted or bottled third gen exceeding 160 MPH , would be to drop it out of an airplane at approx 15 to 20 thousand feet , give or take an inch or two .

I wish you luck ..........

 

Or , to paraphrase Brody in the movie Jaws ;

"Your gonna need a bigger boat"

......

 

HAHA!! I mean top speed! I mean absolute max speed of the vehicle on a long straight!
It would be nice to have a speedometer that reads more than the stock one does and doesn't brake when hitting the trip zeroing needle.
155mph absolute top speed of the vehicle is not that hard to do. It's going to be able to do that with a new transmission :-D

With the 700R4 it sucked major *** when I hit 5500rpm and 125mph on third gear and then a Volvo flew past me like I was standing still.

 

Got my self a set of 4gen pedals. They are rusty but I'll clean and paint them.

 

Very good beginning. Your 3.23 gears won't be too bad, I have 3.07 gears in my corvette
with a swapped in T56. It runs great, but it would be perfect with about 3.73. Good luck
with your swap, you will love it.

 

I've been trying to imagine what's it like to drive manual V8 car. I have a Ford fiesta ST as a winter car and it's got absolutely no power but it's still more fun to drive! Lightweight, good chassis, manual 5 speed. When driving on a street with th700r it's really frustrating because it doesn't allow the engine to be in its powerband, it just feels slow all the time. It's not actually slow but it feels slow because it pulls so smoothly. With one gear looong time.

 

Your car will "FEEL" much faster. It my not BE any faster but it really is nice. My best
friends car is an automatic '91 Corvette. My car feels raw and fast, his is very smooth.
A trip to the drag-strip soon will answer the question for us.

 

Here it is! The transmission arrived today :-) but I realized that "shifter included" does not mean that the actual shifter stick and the **** comes with the transmission. So I ordered those and speedometer cable conversion, yoke, u joint, speedo gears, wiring harness for back up lights and for reverse lock out solenoid. Starting to get excited here! :-D

 

More photos. All I need now is flywheel bolts and pressureplate bolts. And my shifter stick, ****, yoke, to come from summit racing. Then it's install time. :-)

Is it ok to change the thread name? And how do I do that? I would like to change it to: "T56 Magnum swap" then list all the parts needed and tell people how it went. Because when I did my research there was not a lot of information about this.

 

Pedals are almost done.