Cheapest road racing transmission to live behind a 550 HP 383?

I'd reach out to the fine folks at AutoGear about one of their Syracuse M23 HD gearboxes.  This is essentially a Muncie on steroids, with most (if not all) of the limitations of the stock GM box solved for.  I'm running one behind a fairly mild 320hp 310ci in American Sedan, but there are a lot of Nationals-level guys running 475hp+ with that box and no issues (aside from your usual racing related stuff). 

http://www.autogear.net/motorsports/

I can't link directly to the post, but scroll down to the bottom of this page to see how they put one of these things together, as well as a few comparisons of stock Muncie stuff versus AutoGear parts.

This past season I ran an AR5 out of a Chevy Colorado with the FabBot adapter kit.   I'm making 480whp and so far so good.  Less than $1000 for the whole setup including having an aluminum driveshaft made.

This is the same transmission used in the Pontiac Solstice and Saturn Sky also.  

Look for a single groove input Saginaw 4spd- 2.54/1.81/1.44/1.00 or a no groove 2.84/2.07/1.35/1.00

Saginaw's can be found for a few hundred $$ or less and are stronger than the T5. They do have an iron main case and tailhousing, but that added weight is close to the ground and in the middle of the car. 

That said, you can also get a lot more thru most any manual transmission if you pay close attention to the "hit" of your clutch. Here's a list/links to devices specifically designed to reduce transmission/drivetrain shock by slightly extending clutch slip time...

weedburner said:

Look for a single groove input Saginaw 4spd- 2.54/1.81/1.44/1.00 or a no groove 2.84/2.07/1.35/1.00

Saginaw's can be found for a few hundred $$ or less and are stronger than the T5. They do have an iron main case and tailhousing, but that added weight is close to the ground and in the middle of the car. 

 

Just curious, why would you prefer the saginaw over the muncie or the T10?  Is it because they can be had for much cheaper and the use of a clutch control device can help keep it together?

In reply to ssanto :

I found an M20 in "good condition" with the shifter assembly for $650 obo... good deal?

And I found a 4 speed Saginaw without shifter for $400 obo, but no shifter.  Looking at the cost of the shifter, that'll put it as expensive as the M20.

You really need a Jerico, G Force T101 A or similar.  The old Muncie M20 and M21 are good for only about 375 lb ft of torque.  The M22 if you can find one at a decent price might be about 25 percent stronger.  Autogear bought the rights to the muncie and they make a fine, strong M23 up to the task, but it is about 2500 new.  Used Jerico's and the like are about 2500 to 4000.  John the Muncie guy in Fl might be able to build you an M22 for 1500 or so.  I have his contact.

In reply to ssanto :

Watch the sites as Christmas approaches you can sometimes get a real bargain. A Saenz tends to be a better road race transmission  because 5 speeds instead of 4 and 5th isn't,  Is not,  over drive. That makes ratios closer  Plus a lot of groups limit the car to 4 speeds. 
 

 Check Muncie's carefully  it's weakness isn't the gears especially with M22's  It's the case. Over about 350-375 ft pds of torque and a long hot race the gears try to spread the case.  One trick guys will do is use a center punch around the bearing housings to bring the gears closer together to maybe get one more event. 

ssanto said:

weedburner said:

Look for a single groove input Saginaw 4spd- 2.54/1.81/1.44/1.00 or a no groove 2.84/2.07/1.35/1.00

Saginaw's can be found for a few hundred $$ or less and are stronger than the T5. They do have an iron main case and tailhousing, but that added weight is close to the ground and in the middle of the car. 

 

 

Just curious, why would you prefer the saginaw over the muncie or the T10?  Is it because they can be had for much cheaper and the use of a clutch control device can help keep it together?

 

 

 My Saginaw recommendation was because it can be found in good condition for less money than the typical Muncie or T10. Also no worries about a bad case.

I would prefer a close ratio Toploader over all the other oem 4spds for road racing, it's basically what the Jerico is patterned after. Also, you can buy parts from Liberty to turn it into a DIY dog box. The wide ratio dog box Toploader in my car weighs 91.4lbs full of oil, even though it has an iron main case. Not sure what the current prices are, but when I did mine the faceplates were $65 ea, 3/4 face plate slider was $100. I also did 2nd gear...

I wanted to leave 1st gear synchro for this street driven box, so i modified one of Liberty's faceplates and added it to the 2nd gear side of a stock Toploader 1/2 slider...

Grant

I called G Force and I can get a gear set for my T5 for $1350.  Add on another $150 for a refresh set will put me at around $1500 to upgrade it.  Assuming I could sell the transmission for $500 (maybe?) then I'd be all in cost-wise at around $2k.

So if I'm considering that as an option, I should also consider selling the T5 and putting that $2k towards something else.

I'd boot the T5 and invest in something a bit heavier duty.  Those didn't last behind 300hp ASedan cars 20 years ago, even the World Class versions.  I kicked around the GForce idea, and while you can make anything last if you're gentle enough with it, I knew that as soon as the green flag dropped, the "red mist" would set it in and any mechanical sympathy would be a fond memory.  

The old T5 strategy used to be to have three of 'em....one in the car, one on the trailer for when the one in the car eats itself, and one on the bench being rebuilt to replace the one on the trailer.  The GForce box would probably last longer, but there are inherent limitations in the design of that trans.

I went with the AutoGear with the "buy once, cry once" mentality, but any of the above options suggested would be more stout than the T5.

I've been doing more research and it looks like Super T-10's are quite often used in circle track and road racing.  Especially ones built by Tex and Richmond.  On paper they don't seem strong enough... but I keep getting confused because when I read things about not having enought torque capacity to handle "racing" they are normally talking about drag racing.  I can see how 5k RPM clutch dumps with slicks would be a lot harder on a transmission than road racing.  And especially if I use one of those clutch tamer devices posted earlier.

So I'm leaning towards a Super T-10 now.  

Also, whatever happened to Tex Racing?  I saw an article about them getting bought out by Hawk back in 2000.  Did they stop doing transmissions after that?  I suppose any Tex transmission I find out there are 20 years old by now?!?

What are they using in the Aussie SuperCars?

 And especially if I use one of those clutch tamer devices posted earlier.

Those devices reduce shock loads to the trans and the rest of the driveline.  

It appears I am the only one here who has ever absolutely dominated a road course in an auto trans.

I assume this is a 383 small block?

I know they've been mentioned, but the LT1 T56 is a good choice for $1200.

AwesomeAuto said:

It appears I am the only one here who has ever absolutely dominated a road course in an auto trans.

 

I assume this is a 383 small block?

I know they've been mentioned, but the LT1 T56 is a good choice for $1200.

Hmm.... I think the T56 could be a good option.  One area that I've been struggling with is the variety of courses I'd want to run the car on.  One of them being COTA with 150+ mph speeds in the long straight.  Having a 5th gear would be very helpful so I don't have to gear the rear end for those top speeds.

Is there any downside with going the T56 route?  There's gotta be a reason why there are so many people using the 4 speeds...

When GM and Ford exceeded what a T5 was capable of, they both chose the same solution: the T56. 

I found a recently refreshed stage 2 LT1 T56 (claimed 600 HP capable) for $2000 and it comes with bellhousing, new clutch, master/slave cylinders and shifter.  That might be a good route.

I've come full circle.

I have now decided to hold our for a dog ring transmission like a Jerico or Tex 101a.  I think this will be the best bet in the long run.  I think I should be able to pick up a used one for $2500 with shifter.

Anybody ever heard of Rankin transmissions?  I found one with a shfter and the ratios I need for a good price.  I was hunting for Jerico and Tex because that's what I've been hearing.  Never heard of Rankin.. any clue?

Thanks,

Sal

ssanto said:

AwesomeAuto said:

It appears I am the only one here who has ever absolutely dominated a road course in an auto trans.

 

I assume this is a 383 small block?

I know they've been mentioned, but the LT1 T56 is a good choice for $1200.

 

Hmm.... I think the T56 could be a good option.  One area that I've been struggling with is the variety of courses I'd want to run the car on.  One of them being COTA with 150+ mph speeds in the long straight.  Having a 5th gear would be very helpful so I don't have to gear the rear end for those top speeds.

 

Is there any downside with going the T56 route?  There's gotta be a reason why there are so many people using the 4 speeds...

 

 

The one thing to remember when thinking about using overdrives to go *really* fast is that, at 6500 rpm with a .7 OD, the driveshaft will be spinning at 8450 rpm. I'd sooner run a little taller gear to get the speed. 

snailmont5oh said:

The one thing to remember when thinking about using overdrives to go *really* fast is that, at 6500 rpm with a .7 OD, the driveshaft will be spinning at 8450 rpm. I'd sooner run a little taller gear to get the speed. 

This.  Lower 1st gear and taller diff gears is better as far as keeping driveshaft speed down.  That's one of the reasons why a lot of manual trans 5spd BMWs had a 1:1 5th gear into the early 2000s.  

In reply to snailmont5oh :

Oh my... that IS a good point.