What are my options for a manual trans hooked up to a 455.......in a 1978 Z28

Hi, I've been contemplating putting a spare 455 in my 1978 Z28. Car is a factory 3504-speed car with 3.73 rear gears.

I don't want to be going down the highway and spinning the engine at 3100 rpm's at 70 mph. So an overdrive transmission seems like the logical choice.

I know about the GearVendor's units. But I guess I would just prefer either a 5 or 6 speed trans like a TKP600 or T56. I've been doing some searches and reading and most of the posts are older.

I've seen the stuff from Keisler and was going to give them a call. I was just wondering if anyone here has had any experience with this kind of setup. Thanks.

 

This is just my opinion, and I don't mean to offend but we all know how much that varies between us. I would keep the 455 for a spare or another Buick project. Putting it in the Camaro certainly won't help the value of it because in the same way we like Buick engines in Buicks, most Camaro people are going to want a Chevy engine in their Chevy. If you plan on keeping the car forever then that's a different story. If you want more power, which I certainly understand because that generation of Camaros were slugs, think about a 406, a 383 stroker, or a ZZ4 crate motor for the car. There are hundreds of choices there and you won't have any issues with it. Same mounts, exhaust, fuel line on the same side, etc., and those small block Chevys love the rpm so you could retain the T-10 and 3.73's.

 

I got the car for next to nothing. It's practically rust-free, and has NO options. I don't care about originality. I just want a car that I can row the gears during the summertime.

And I don't want to drive my Buick all around. It's been hit twice now in parking lots. I've got a dent in my rear bumper and now my front fender. And with the potential value of the car if restored properly, I don't like leaving it alone if I'm not at a Buick event.

The Z is going to be a fun car. I've looked into a LS-series engine, a 406 or 421. But I already have a blue block complete 455 just sitting in my garage. And I know it wouldn't take much past a simple re-build to put some serious torque in that car for a small amount of $$$$ vs spending $4-5K for a Chevy/LS engine that will make the car perform the same. A simple bottom end freshening up, an Edelbrock dual-plane intake and the right cam with some 1970 455 or 1967 430 heads and I'd be on my way.

 

Your front Subframe should be the same as the one in my car. Just get the ~'70-'73 A-body engine mount frame pads, bolt them in. The Camaro Z-bar should work just fine with the Buick block. Mock it up before bolting in the frame pads to be sure (I didn't, but it worked out). I have a TKO-600, 26" tall tire, 3.70 gears and cruise at 75mph around 2200rpm. You'll need a BOP or Buick bellhousing of course.

 

One option I can think of would be a Doug Nash 5 speed, which is now a Richmond 4+1 and should stand the torque of the 455 and position the shifter close to the original location. They have a 1 to1 5th gear but they offer 1st gear choices of 3.27, 4.06, or 4.41. It should bolt directly to a standard BOP bellhousing. The Camaro should have an 8.5" rearend so you could swap in a 2.73 or 3.08. Most of the Tremec 5 and 6 speeds wouldn't tolerate the torque of the 455 unless you go with the T-56, which is more expensive and has a top loader shifter that would be positioned much further back and the stock console would have to go. Even your original T-10 would have a limited life span behind a 455.

 

I don't have a center console in the car. Like I said before, no options. So I'm not too concerned about where the trans pokes through.

 

I have experience with the T56, T-10, Muncie M-22.

If cost is an issue, stick a 3.08 in the rear, and go with a regular 4sp. Doesnt rev to the moon, and for street driving i think its a great setup. You wont notice any downfalls with the 3.08 with buick torque.

If 3.08s are too wimpy for you, go with the TKO from Keisler. Ive done the research, and it will NOT save you any money to shop around for parts. Its pretty much the cheapest option to get it from them.
If you ARE going with keisler, id recommend getting a good SFI approved bellhousing (like McLeod, Lakewood, or Quicktime), and a McLeod clutch. Just subtract those items from the kit when you order.
Figure out what gear/tire you need to turn about 2200rpm with the 0.64 or 0.78 (whichever overdrive you choose) in 5th, and go with that gear. Perfect RPM for cruising.

If you want to get 6 gears, theres a couple avenues to explore as well, but involve a bit of parts hunting.


Whats your budget? What kind of power you making with the 455? What are you planning to use the car for???

3 very important questions.

 

I wouldnt recommend the dougnash/ richmond 5 sp. If you look at the torque ratings for the trans, they are very low.

Sure it will withstand the torque of a 455, but so will any other 4sp, or a stock T56. Once you make any modifications (which you will), its obsolete.

The price to performance ratio doesnt add up for me on the DN/Richmond trans. You can get the tremec for almost the same price.


Personally i like tremec because they have been in the overdrive game for a long time. Richmond only started offering overdrives recently. Their 5spds used to be 5th = 1:1. The richmond is designed to be a "hassle free, non invasive" 5 spd install. Ie: same shifter, clutch, and mounting. The tremec was just designed and later adapted to earlier vehicles.

Heres some interesting facts. I cant seem to find the torque ratings for them anywhere though. The TK0 600 is around 600ftlbs i think. The stock T56 is about 450ft lbs.

http://www.5speedtransmissions.com/5sp_comparison.html#Shifter

 

BUDGET!?!?!? We don't have no stinkin' budget!!

Are you kidding? I'm Polish and married to a polak.

But seriously, it's going to be a summer driver. But I must be able to shut down any ricer or kid with a Mustang GT. And I'd certainly like to be able to hold my own with a new Challenger or Camaro SS.

The 455 would get "warmed over". But nothing too radical. I'm thinking cam in the 220-230 duration and .500 lift or lower. I can do some mild port work to a set of iron heads. Then an Edlelbrock intake and probably a 800 q-jet. I feel pretty confident that I can be solidly in the 12's with that. Heck, my car weighs 500 lbs. more and I was in the high 12's with a 3.08 rear gear.

Keisler does seem to be the most efficient way to go. But I'm sure it'll be a $4K price tag by the times I'd be done there and get the bellhousing and clutch. Then another $2.5K for the engine, $3K to paint, $2K for an interior, $2K for a nice suspension setup and $1.5K for an aftermarket a/c setup.

Dang!! I just spent $15K awful quick.

 

One thing at a time.

Go with the TKO 600 then, a few guys running that on the board. It can handle 600 ftlbs, and put the biggest (numerical) gear youre willing to tolerate in there.

Im planning to put a T56 behind my 455 (just because thats what i have). Ill be rebuilding it to viper spec (almost 700 ftlbs). The end cost is almost the same as a new TKO 600, but with the 0.5 6th gear, i can afford to go as high as a 4.56 rear gear and still be able to cruise on the highway at around 2000 rpm.

I would do some research on gear ratios if performance is important to you. The T56 1st gear is rather small (numerically) @ 2.94. I dont mind it because of what i use my car for, but it does bother me if im trying to go uphill on my freind's unpaved driveway. The SLOWEST i can possibly go without stalling is 20 km/h (Thats really fast). Performance wise the TKO is the better way to go. This is with a 26in tire and 3.42 rear gear.

theres lots of kits and stuff to get a T56 into just about any car now.

 

The car rearend is already a 3.73. I was just going to put new axle seals and bearings in and flush/replace the diff. fluid.

 

TKO 600 or T56 Magnum.

 

On a budget? Try an MY6....or as its called in Moper circles, an A 833. Dirt cheap four speeds with 3.00 first gear and overdrive for forth. Used to run em in my former Regal.

 

I'm sorry, but I have my standards. And I could never put a MOPAR part in anything I drive. Not even a Chevy.:laugh:

 

GM had their own version of pretty much that exact trans. I forget the numbers on it. NP440 or something like that.

 

You are correct. Even though these were Chrysler built, they had GM splines, bolt pattern, mounts, speedo cable, etc. I actually took mine out and ran a T-10 for awhile, then I put the NP back in. I liked it better!

 

Floyd thats interesting. Never knew that was an option.

What do you like better about the NP?

 

I've never heard of an NP440. What did they come in?

 

The A833 overdrive came in early 1980"s GM 1/2ton 2 wheel drive pick-ups... Very weak, very hard to get parts... Crash

 

I know a guy that runs one behind a 406 Chevy in a '65 Impala, it's been there trouble free for ten years.