Transmission

Power is a must to achieve certain goals. Goals such as 10 second time slips with at least 500 horsepower in a 3200 (or less) pound car require a transmission to deliver this. A TH-400 is the strongest transmission but could it be too big that you lose power? A 2004R is smaller and easier to turn, but can it be built up to be as powerful as the TH-400. What about SP Transmissions, what is it that they have different?

 

Steve, the 200-4r can be built to handle the power, will it ever be a s strong as a t-400? I don't think so, some may have a different opinion here.
It is expensive to get the 200-4r that strong.
As for using less power to drive it, maybe , maybe not. I can tell you from personal experience, every car we have run a 200-4r in vs . at s-p t-400, the 400 has always been faster by at least .4 seconds. Mph is better on the 400 as well.
I build them both, run them both, and still like the 400 better.
The differences between a t-400 and a s-p 400 is in the pump and input shaft, the rest of the tranny is the same.

Jim Burek P.A.E. ENTERPRISES

 

I looked into this. It was about $2500-$2700 with a converter to build a 200R4 to go behind a 455. You'd be better off strength wise and same money with a TH400 and an overdrive unit that bolts up behind the tranny. GearVendor I think is the name.

Here's the link:http://www.gearvendors.com/index.html

I believe the unit for a 455 is in price code A, which is $2395. Plus you now need to get your driveshaft shortened. Good luck.

Phil

 

What about a TH350? I've heard they can be built up to handle some pretty impressive numbers and put less of a load on your engine. In fact, I've seen a few posts on this board from guys running a 455 and TH350 combo. Any recomendations? I don't know what the cost would be to do this but it's an option.
There was also a recent article in either Hot Rod or Car Craft about power loss. They had a GSX as their mule and found approximately %20 loss of power through a TH400! They speculated that a 350 would be somewhere in the mid teens.

 

Yes , the 350 can be built to hold up also. It is still not as strong as the t-400. The main reason the t-400 requires more power to run than some of the other trannies is due to 2 things, first , it's parts are bigger and heavier, thus it's great power handling ability. Secondly, remember , the t-400 came out in 1964, has'nt changed a whole lot since 1965 other than getting made with cheaper parts over the years, the late 400's have plastic pistons and other plastic parts in them they did not have in the early years, and the other later model trannies use more rollerbearings inside to help reduce friction. The 400 can be upgrade with roller bearings which puts it's power robbing numbers eqaul to or better than some of the later model trannies.
It's funny, guys seem to always be concerned with making sure the engine has all the best stuff in it soas to not break it . Seems this way of thinking gets tossed out the window when it comes to trannies. Lets see if we can make a weaker tranny hold up to our brutal big block by putting bandaids in it.
The trend for the chyrsler guys is to use the smaller and weaker 904 in place of the bigger and stronger 727, ford guys put the weeny c-4 in place of the stronger c-6. Now Gm guys are wanting to use 350's in place of 400's.
I'm not in any way saying the 350 can't hold up, But I will say that I don't beleive it will last as long behind lots of power like a 400 will.
I'm not talking as much about clutch wear here as much as hard parts, ie palnetary sets and so forth.
Over the past 29 some years of building trannies, here is what I have discovered. I have seen more t-350's with bad internal parts , such as shafts, planetary gear sets , bands and pumps than 400's. And I have done probably 40 times more 400's than t-350.

Usually the worst case I run into on a 400 is that all the clutches are burned on trannies we pick up for rebuild, but that is only on only about 25% of the trannnies we come across. The 350's are about 85% burned up clutches and usually at least 50% have bad input shafts, planetary sets , or pumps.



If we want to continue the idea of using a weeny tranny to shave a tenth or 2, maybe we should try to use the metric 200 behind a healthy big block, I'm sure it will hold for a couple of passes down the track before it grenades. I've got some out in the yard I could build if anyone is interested.

All I am trying to say here is that I have comfort in knowing that with a 400 tranny in my car, that is one thing that I don't have to cringe about going down the track wondering if it will hold up to the abuse.
I guess the reason I am so into 400's is because of the s-p set-up, which I still truly love. We have had 9 second cars with s-p set-ups, and because of the s-p set-up, the cars are still streetable. Jim Burek

 

Jim, I'm sure you know this, but I'm amazed how many Ford, Chevy, and Mopar guys are out there who have never even heard of a switch pitch tranny. Even guys at transmission shops look at me like I came from another planet when I mention one. They think the plug on the side is for emission control on all th400's. That's probably because they were only used on Buicks and Cadillacs for a few years before '68. :spank:

 

You are correct, but don't forget olds used them as well.
Very few tranny guys today even know what a s-p is . Jim Burek

 

Jim,
I agree with you 110%. :TU: Finally the truth about the way some guys feel about trannys. They spend $1.000's on the motor and then want to get by with a $100 trans patch up job. ou:

Mark

 

I bumped into a guy at a show with a '64 olds '88 (I think) and he told me the car didn't have a torque converter. It was a direct drive unit from the factory in the automatic trans and was only used 1 or 2 years. I can't remember what he called it, but I found that very odd and hard to believe.

Have you ever heard of one of those?o No:

 

64 Olds 88 had a Roto-Hydramatic trans (aka Slim Jim). No torque converter per se, but had something called a drive torus internal to the trans.
It was used in many Pontiac and Olds models from 61-64. In my opinion, a pretty nasty transmission.
Some models of Olds/Pontiac/Cadillac also used a unit called a Controled Coupling Hydramatic (had some other names through the years as well) that was supposed to be a 4 speed automatic. This one had a torque convertor.
Olds and Pontiac got the TH400 in 65. Some models of Cadillac in 64 had the TH400 as well.
Just what I remember from way back then. :Brow:

Mark

 

Question:

As far as rotating weight differences between the 400 and 350 - wouldn't building the 350 to handle the higher power negate this? I'd imagine some of the heavy duty parts would weigh more than stock, reducing the difference.

 

My dad used to have a '62 super 88 convertible.....394.......really hauled. I'll bet that car had one of those trannys in it. L2 was called S for super.:Brow:

 

We used to call them the "L S D" tranny's. Only problem was that they were always a "BAD TRIP". :laugh:


Mark

 

Some of this "smaller is better" attitude comes from people wanting to be like "the big racers do it". Go to an NHRA or IHRA race, look in the Stock and Super Stock pits, and you will see big-blocks with T-350's and small-blocks with T-200's or 904's. And these are 8,9, and 10 second cars. First of all, these transmissions are more than meets the eye. The going price for a competitive Super Stock transmission from Rossler, Kilgore, etc., is around $5k-$6k. Yeah, it's a T-350 or a T-200, but it has LOTS of aluminum and titanium in it. You can also pretty much pick your gear ratios. They also don't necessarily use transmission fluid. The pumps are relieved to only put out enough pressure to get down the track. There are alot of tricks there. When I talked to Kilgore he said to change the fluid and check the clutches every 30 passes. This is much more tranny than an average bracket racer or weekend warrior will ever need. Unless you're out for a national record, put a 400 in it with some good parts and a good converter. You'll sleep better at night.

Have fun.

 

ou: You mean trying to do what dedicated drag racers do for a street car isn't a good idea?

 

I've been having this conversation with myself for a couple months now. S-P T400 or 200-4R behind my new 455 Jim Burek is building.

I really like the idea of the overdrive in the 200-4R. Pretty much any show we go to is going to be a hike. Whether it's to a BPG picnic in NY/NJ or to one of the Nats. We're talking serious highway travel from Cow Hampshire. The overdrive trans would still let me have decent performance around town and the once or twice a year I travel to the local track; but also drop the rpm's on the highway for better mpg and less stress on the motor for traveling. The downside is cost over the T-400, but putting the GV overdrive unit behind the T-400 pushes it out of reach in costs.

What rpm's are you S-P guys seeing on the highway at say 70 mph? What gearing are you running with that?

 

http://www.bgsoflex.com/auto.html

Scroll down from the link above for RPM/MPH numbers for different tranny, tire size comparos. The 200 4R has a 0.67 4th gear while the 350/400 is 1.0. You can compare speed vs. rpm there.

I'm on the verge of getting a built 200 myself. I've always wanted one and have had no luck getting my VP400 to behave. It shifts 'ok', the converter works fine, but it pushes the dipstick out at WOT and leaks. I'm tired of pouring $$$ into it. And, living in northern Nevada a trip anywhere is a long trip, the suspension is setup pretty well for the twisties, I don't have a real lumpy cam to need the VP on the street, and I figure I'll drive the car a lot more with the OD (isn't that the idea?). I race once a year in Vegas so maybe this fall I can drive it down there.

 

Gary,

Having owned a GN since new I am very familiar with a good 2004R and how nice they are with 3.42 gears and short 26" tall tires. After researching it useing amoung other places the Turbo Buick site. I decided to use one for my big block Cutlass. I selected an experienced builder that somewhat specializes in hi po 2004Rs and had a long successful track record in building them for fast cars.

That being said if you don't live in a remote place, travel much highway and put on at least 5,000 miles on an average year. I don't know that 2004R is worth the extra money over a S.P. 400 upgraded with the roller bearing and such. It takes a lot of extra gas and engine wear to make up the cost.

Speaking of cost I started out with and provided a good core from an 84 T-type parts car. This helped lower the cost because it provided the right valve body and a good strong proper stall lock up converter, the stock D5. To clarify a reasonably good converter for my cam/combo and from what little I know probably yours.

My understanding is if you don't start with a core from a GN/442/MCSS you have to use a modified valve body, which is expensive or time consuming. (same difference to me) The modified valve body has shown to be a less than a consistant proven repeatable science with regards to getting the correct part throttle shifts. Thats is as I understand it from my tranny builder.

Because I am using it behind a big block as oppossed to a turbo car. Also because I expect it to make crazy torque maybe 575lb ish around 3500 to 3900 I used the billet drum. Downside to the billet drum is extra cost and a more harsh part throttle shift. fyi as you may know big block torque "hits" or comes on harder than a turbo which is why they are harder to hook and harder on parts. Anyway mine for a street strip build only cost $1,100 delivered. This included free adjustments and tuning if its not right untill it is right and it included a warranty for rebuild for x mileage. Keep in mind I provided the core and did not have to buy a converter.