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Stephen717 04-23-2019 12:30 AM

Transmission help
 
Ok. I know I'm gonna be pushing a soapbox down the road and most gas mileage goes out the window. What I'm wondering is until I can build the big block I have and afford an m22 what is a good 4 speed to put behind a 250 l6 since my truck now has a 4.10 rear axle in it. Don't want to go down the road stuck at 60 revving at 3,500-4,000 rpm with the Saginaw 3 speed. Any help would be great.

Thanks

frank69 04-23-2019 01:47 AM

Re: Transmission help
 
m22 and 3spd both 1to1 in high gear no advantage on hiway

Greasey Harley 04-23-2019 02:32 AM

Re: Transmission help
 
I think some taller gears in your rear end might a better solution than a different trans.
or
You could maybe try some taller rear tires, that would be cheap and easy.

Mike C 04-23-2019 07:47 AM

Re: Transmission help
 
Find yourself a T5 from a 4.3 S10 truck. Search here on the board for T5 conversions. That will give you the best of everything driveability wise.

None of the passenger car 4 speeds are a good swap into a 6 cylinder powered truck. SM465 if you work it.

Bigdav160 04-23-2019 01:44 PM

Re: Transmission help
 
Has anyone tried to use an overdrive version of the A-833?

Oh, nevermind. I looked on eBay and people are asking stupid money for one.

Overdriven 04-24-2019 01:35 AM

Re: Transmission help
 
As mentioned your 3spd is 1:1 in 3rd gear same as m22 in 4th. My advice would be to figure out what you want your highway cruising rpm to be with the big block. There are gearing/speed calculators online that’ll help you figure out the rear gears required to get that highway cruising rpm. Install the gears, leave the 6cyl and 3spd until you can do the big block m22 swap. 3.08 gears and maybe 3.23 too, might be hard for the 6cyl to pull from a stop and uphill on the highway though.

Btw with 4.10 and 28 inch tall tires at 60mph it’s actually 2950rpm. Add 100rpm for every inch shorter your tires are, subtract 100rpm for every inch taller your tires are, roughly. With 3.73 and 28 inch tires at 60mph it’s 2700rpm, 2450rpm for 3.42, 2350rpm for 3.23, and 2200rpm for 3.08 gears.

Robert Crandall 04-24-2019 02:39 PM

Re: Transmission help
 
Another no cutting or fabricating change would be to change the complete rear axle assembly, if you have access to one. I found a 3.08 in a V8 AT Suburban that I put in place of my 4.10. It made a nice difference. I like it for the interstate. Conversation became possible on the interstate, and an added bonus was an end of slinging oil out the rear seal.
East coast Virginia is table top flat, so I can get away with slowly gaining momentum in place of accelerating. A negative is that at speeds less than 35 mph I am in second gear to crawl up an overpass. If your Harpers Ferry is the one in the West Virginia mountains, then you may not want to go quite that high with the gearing.

Stephen717 04-24-2019 11:12 PM

Re: Transmission help
 
Let me rephrase this. Eventually I will have this truck just as a show truck. That's what the big block will be for. Going to shows and running at the track. In the meantime I will be running the stock 250. But with the 4.10 rear gears and the 3 speed I would be screaming down the highway. So I'm looking for a transmission to put in it for now until I change to the big block later. Then when the big block and m22 are in like I said. I will take it to the track and to shows and I might take it to work a few nice days a month. But for now this is purely to try and keep the rpms down when on the highway for when I go back and forth to work

kwmech 04-24-2019 11:28 PM

Re: Transmission help
 
What's the time frame for installing the big block? 1 year-2 years?

Stephen717 04-25-2019 12:19 AM

Re: Transmission help
 
It's going to be at least 2 if not 3 years before I can get all the parts to build the big block + the transmission I want behind it. Which is why for now I'm looking for something better than the Saginaw to put between the 250 and the Eaton rear... Would an nv3500 work

kwmech 04-25-2019 01:14 AM

Re: Transmission help
 
I'd be installing the ratio you'll run for the big block combo. Which trans for the big block? Tire size. Decent all around ratio may be a 3.42

Mike C 04-25-2019 08:28 AM

Re: Transmission help
 
Why not search for the T5 conversion as I mentioned earlier? Lots of 6 cylinder guys have made that switch and it is ideal.

And why the M22? Just because people throw that around all the time? There are VERY few real reduced helical angle Muncies out there but everybody likes to say they have one. And they all have a 2.20 first gear same as the M21 which is a TERRIBLE choice for the road IMO.

The Super T10 is available with more first gear choices, and if you insist on a Muncie, the AutoGear trans have some options.

I broke the 2.64 first gear Super T10 in my Camaro and replaced it with a 2.42 first gear trans and even with the 4.10’s in the back I miss the extra first gear multiplication.

For my ‘64 Corvette that I am swapping a 427 into I chose to buy a McLeod street 5 speed. They rate it to 500 #/ft and it fits with zero mods to the floor of the car which most other OD choices don’t. It is really a beefed up T5 using aftermarket gears in a unique case. Time will tell if that is a good choice...

But it has a 2.95 first gear and a .68 overdrive. So the 3.73 gears in the back will launch like the M22 with some 5.00 rear gears. And it will cruise like it has 2.35 gears in the rear.

The 4.3 V6 T5 from an S10 gives your inline 6 the same benefits. Better acceleration in all the gears and lower cruising speed. Along with a fairly low buy-in cost and swap difficulty.

Hard part is finding a trans anymore since most of those turds came off the road awhile back...

http://www.inliners.org/Jack/t5_page.html

Stephen717 04-25-2019 06:36 PM

Re: Transmission help
 
I can honestly say that I didn't see your post about the t5. I will have to look into it. As far as the m22 the area I grew up in that's all I ever heard about was this legendary transmission and my grandfather had one in an old El Camino. I only know that cause I saw the gears when he had it rebuilt. I've been under the impression for awhile that it was the transmission of choice for an old school build. But the more research I do the more I think about a 5 speed. I've heard a lot of good things about McLeod. I might go with them instead of a Muncie. There is a guy down in Florida who used to build brand new ones. Looks like he stopped building them and is building the st10 now. Look up www.5speeds.com he has some good stuff from what I've seen anyway to get back on topic I will definitely look into the t5 for the time being. Thanks for the advice

LockDoc 04-25-2019 10:07 PM

Re: Transmission help
 
-
I put an S10 5 speed OD in my '67 I6 farm truck a few years ago and it is still working good. I used the stock bell housing and clutch components and an '85 Astro Van 11" clutch disk.


Here is a good thread with some pictures on the S10 install.

http://67-72chevytrucks.com/vboard/s...d.php?t=412435

I also put an NV4500 5 speed overdrive transmission in my '72 C30 that had an SM465 in it.

http://67-72chevytrucks.com/vboard/s...d.php?t=673588

This worked out excellent..... On the cheap.

LockDoc

akart 04-25-2019 11:01 PM

Re: Transmission help
 
I have 4.10 w/a sm465 trans,350,tires are Cooper 235/85/R16 they are 31.89" in dia. @ 60 I am doing 2592 RPM @ 3500 I am doing like 83 MPH. I like these RPM's and the torque is an all the right places. Wouldn't change a thing. 13.5 MPG and I can do better. What do you have for tires??

Stephen717 04-26-2019 02:03 AM

Re: Transmission help
 
On the replacement frame 9.00x16.5 on split rims. On the original frame I believe I'm running a set of 235/70r15 jetzon innovators that are 11 years old. I refuse to take them on main roads. I am changing the split rims to a newer set of rims from a 90's truck for the time being until I can afford a good set of rims. Anyhow I think the t5 is my best bet. I'll be running the bfg tires off my fathers old truck (will get the size in the morning) so I'm not running on bad tires. Although I'm gonna have to change the front two from where he never got a front end alignment. Thanks to everyone for the help so far. Keep the info coming

Overdriven 04-26-2019 08:34 PM

Re: Transmission help
 
The t5 is a good budget option, but it won’t be that great for your future big block and drag strip passes. The Tremec TKO 5spd’s would be better suited and you could run it now with the 6cyl. Depends on your budget and where you want to invest it right now.

There is a company http://www.autogear.net/ making new Muncie 4spd’s and they have lots of options for them. Want a really deep first gear (2.97) and run highway rear gears, you can have it, for a price. That price gets pretty close to a TKO before you change rear gears to suit the m22, TKO you can leave your current gears for now at least.


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