O.d.

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No Worries,Thanks for the apology. No big deal. I have a 400 block,I have a 71 340 block and forged crank,also have a complete 440. 451/stroked 400 using 440 crank and rods fits A body better. #40,cause I have options. 440 wasn't brought up cause I've built a few and know what they can do. Never used a mopar overdrive 4 spd. I have some regular 4 speeds. Lookin for a less expensive route than a gearvendors,thats all. Never used a mopar overdrive. drove a couple on 318's that others owned. They had round shifters on them that were sloppy. Didn't know if the pistol grip shifter would work on one. Although it sounds irrelevant if the OD won't take the abuse. Researching before spending. When younger I did it the other way around. Little smarter now...
 
Thanks for the explanation. I read it on the internet, so it had to be true, right? lol

My apologies for any misinformation.


yellow rose said:
The countershaft always turns. Period.

The difference is, the 4 speed OD is not really a 4 speed OD but it is a 4 speed that Chrysler modified the shift rods so that when the shifter HANDLE is put into the 3rd gear position, the gear box is actually in 4th gear, which is direct. All that means is the disc, input and main shaft are all turning in the same speed. That would be crank speed.

To get it to overdrive, you put the handle in the 4th gear position, but the gear box is actually now in 3rd gear. And since you can never turn something overdrive that is directly driven, the engineers made 3rd gear overdriven. That's how they have an overdrive.

Does NOT matter what the trans is, the counter gear is always turning. Is power moving through the counter gear? In every gear but the direct gear, which is 4th in a standard box, and what they call 3rd gear in the overdrive box (which, as I said is really 4th gear, but you flip the 3-4 lever down instead of up and it changes what gear you are in, relative to shifter handle position).

Is the OD really any weaker? Depends on who you ask. I have only used one on the street, and that was 1980 on accident. We tried to break it, but never did. Didn't have much HP, but we would get blind drunk and beat the snot out of it. We finally gave up. Obviously, more HP and bite, or a bad clutch and I could have destroyed it.

I was told the counter gears are what are weak. They have a different bearing arrangement or something. Use one with caution.

One last thing. It is beyond silly and cheap to run a stick and NOT use a scatter shield. In fact, I would call it downright IGNORANT and STUPID. You don't need to fail a flywheel, or a disc or the pressure plate to need a scatter shield. Doo doo occurs. We are all human and make mistakes. It is arrogance that breeds perfection in our own minds. Why am I anal about this?

I bought my first scatter shield in the summer of 1981 and all my friends (who were mainly stick guys) thought I was stupid. And arrogant. The rules didn't call for it, so they thought I just wanted to be overkill. I had never seen a clutch failure, but I damn sure figured that at some point, they had issues, or why make certain cars use them? And I was very abusive on parts back in the day.

The weekend before Labor Day (and incidentally, one week before the big GO) there was an AHRA National event at my local track. I had waited for it all year. All the hot dogs were gonna be there, but most didn't show, because they were focused on Indy. Saw my first mountain motor Pro Stocks that weekend. Yuill brothers showed up. Pretty cool. Anyway, there happened to be a goodly amount of stick cars there, and as the faster cars came up, my buddy and I walked up to the starting line. I will NEVER FORGET what happened next.

A Pontiac pulled up, and he was a stick. It was about 10:15 so the track was tight. He was in the tower lane, not 50 feet from me and my buddy, if that. They stage the cars and the Pontiac goes to the mat. I don't think he got his foot off the clutch and there was a VIOLENT EXPLOSION. As the car in the other lane left and things got relatively quiet, I realized my ears were ringing, and I could still hear the sounds of metallic parts hitting each other and the ground. Everyone was stunned. Finally, the driver got out, and we could see him limping, and his right foot was bloodied up. He went to the ambulance and they drug the car back to the pits.

We made it over to the car, right after the driver and his brother, who owned the car got there. The damage was almost unbelievable. It shredded the tunnel. Blew the dash up in the center. The cab was peppered with shrapnel. The engine, transmission and shifter were JUNK! The driver not only had some serious foot issues, his fruit salad was hit by flying debris and he said that was hurt worse than his foot (I would think so).

We talked for a bit, and then they wrote "for sale" on the back window. The brothers decided they were done. To my knowledge, they never raced again. You can say they were pussies, or they were cowards. Maybe they were. But we heard the explosion. We felt the concussion. Our ears were ringing. And the damage was almost unexplainable. From a single clutch explosion. So what happened? Was it junk parts? Was it driver abuse?

Nope, it was FATIGUE. In 1981 a mid 11 second car was pretty damned fast and he was in the mid 11's. On Friday, they tore up a disc on the last run. Probably about 9 PM. Being the racers they were, they had spare parts at home. They pulled it apart at the track, and left with the flywheel. They called their engine builder who met them at 6 the next morning and surfaced the FW for them. Back to the track and they slapped it back together. It was their first run of the day, and as far as I ever knew, the last one they ever made. In a hurry, tired from breaking their asses just to get there, running their first National Event and then killing a clutch Friday night, they just were too tired to rely on their own ability to function with out sleep and operate on motor function alone. Neither one torqued the flywheel bolts. One ASSUMED the other had done it. The results were spectacular, horrifying and devastating. The driver could have been killed. The car was pretty much junk.

The moral of the story is simple. The thing we love to do it inherently extremely dangerous. It needn't be a parts failure that gets you. It could be a simple routine, mundane task that gets overlooked. The results are, never the less, paid in money, blood and possibly, a life. I take this crap very serious. I don't care who you are, if you are using a stick, and you are going to go out and treat it like you stole it, then don't be a cheap *** and buy a SCATTER SHIELD. Anything else is dumb. It don't matter if the rules don't say you need it, you MUST have it, you MUST have it. Take a 30 pound flywheel, add a 10-12 pound disc, and a 30 or so pound pressure plate and bolt them up. You now have 70 pounds of ballistic projectile. Now, add RPM to that mass and you get the ability to kill, very easily.

My apologies to the OP. I did not intend to jack this thread. When someone is ridiculed for wanting safety equipment, that is complete and utter stupidity. Any car with bite SHOULD have a scatter shield on it. PERIOD. I appreciate that an apology was made. That was right and good. But the fact remains that very few people have seen a clutch failure, for any reason. If you did, you would only ridicule the fool who doesn't want one.

I hope my long ramble just may change on mind.
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cuda620 said:
No Worries,Thanks for the apology. No big deal. I have a 400 block,I have a 71 340 block and forged crank,also have a complete 440. 451/stroked 400 using 440 crank and rods fits A body better. #40,cause I have options. 440 wasn't brought up cause I've built a few and know what they can do. Never used a mopar overdrive 4 spd. I have some regular 4 speeds. Lookin for a less expensive route than a gearvendors,thats all. Never used a mopar overdrive. drove a couple on 318's that others owned. They had round shifters on them that were sloppy. Didn't know if the pistol grip shifter would work on one. Although it sounds irrelevant if the OD won't take the abuse. Researching before spending. When younger I did it the other way around. Little smarter now...
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I'm not saying you can't use the OD unit. I beat the crap out of one and couldn't break it. Back then we didn't have bite or horsepower.

IIRC it is in the cluster gear. And I think it had something to do with vibration or something. They are essentially an 833 that uses 3rd gear as an overdrive. I have seen pics of a guys car that used a V-Gate shifter with an OD box. You just flip the 3-4 lever down.
I wish I had one to take apart. Who knows, maybe you could replace the cluster gear bearings with a bushing....Id have to see one.

Maybe you try it and see if you can kill it! Then we would all know for sure!
 
cuda620 said:
No Worries,Thanks for the apology. No big deal. I have a 400 block,I have a 71 340 block and forged crank,also have a complete 440. 451/stroked 400 using 440 crank and rods fits A body better. #40,cause I have options. 440 wasn't brought up cause I've built a few and know what they can do. Never used a mopar overdrive 4 spd. I have some regular 4 speeds. Lookin for a less expensive route than a gearvendors,thats all. Never used a mopar overdrive. drove a couple on 318's that others owned. They had round shifters on them that were sloppy. Didn't know if the pistol grip shifter would work on one. Although it sounds irrelevant if the OD won't take the abuse. Researching before spending. When younger I did it the other way around. Little smarter now...
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Thank you for accepting my apology I just get a little frustrated sometimes. The sloppiness a lot of times comes from the rubber mounting of a bayonet Style Shifter. Any shifter can made to be made a lot more rigid. Most of the Bolton kinds are rigid. I actually took the rubber bushings out of mine and made an aluminum spacer and bolted it on instead of the rubber. A lot of that it just for car driving and comfort from vibration not the direct shift that we want from a performance car. I actually have a overdrive transmission for sale for $250 right now but I'll take to the swap meet at the end of the week. I already had a buyer but completely talk him out of it because he was building a Performance Engine. I completely tore mine of heart over the winter and put in all new parts it turned out to be one of the easiest things there's really not much in there as far as clarence's go it's just take it apart and put it back together for the most part. No someone can jump on and get all technical about that but mine's working perfect I guess I just got lucky. I've had all the shifters now I started with the ball I have a pistol grip and now I'm using the v- gate witch I am getting used to and really like. On my break right now at work and just voice commanding this post so if spelling or things get crazy I'll fix it when I get home. And let me say this and I wish I could make it and bold lettering use a scatter Shield I repeat use a scatter Shield I did not mean to say don't use a scatter Shield just don't waste your money building one for a overdrive transmission. And I'll try and quickly post a picture of my transmission that was scattered all over my back patio this last fall and I have since drag race and works great.GOOD TIMES !!
View attachment 20150928_130516.jpg
 
The O/D are pretty tuff, and survive plenty of abuse, I believe the weakness was the small bearing surface used between the imput/output shafts. Even though they went to larger imput/output bearings, 308s, to help take up deflection in the shafts, the same small bearing joining the two shaft now has to take constant output shaft deflection/side-load plus turning faster than the imput shaft in High gear, as opposed to the two shafts locked in high gear, with no deflection .

The output shaft suffers, the "nub" bearing surface breaks down thru wear, as any bearing will.

With the extra H/P, the hemi had a bushed countershaft, that may be worth looking into if you have a countershaft failure.

I wouldn't hesitate to try it, with 3:09 low gear, rear gear selection and camshaft selection would be important considerations.

hope it helps . . cheers

Browse the B-body site, there's quite a few threads on O/D thrashing, and survival.
 
Ok home. I'll post a picture of the over drive and we can see the difference between the two. You can see that tiny little overdrive gear where third is supposed to be. There's not much different about the linkage then the 3rd 4th shifter ear up side down (or facing up instead of down like a 4 speed). First gear is lower for the economy slant 6 and 318. The overdrive gear is for economy on the freeway for a slant 6 and 318 car. First gear would be great and all for taking off, that second gear that has to take up so much room on 3rd and 2nd as in gearing. The overdrive gear it's so small week and not use so much good for a performance application.

LOL well when the clutch is released and the motor is on all the gears are moving all the time. That's why even when the car is in neutral and you release the clutch it still has a small pull on the motor because it's going to get all those gears moving - countershaft and 1st through 4th . Input shaft Is solid with 4th gear which always drives countershaft which always drives 1st through 3rd even when in 4th gear is connected to the output shaft the counter shaft and all the other gears are still turning. It really boils down to which gear is connected to the output shaft. I'll get into reverse for my advanced class LOL
View attachment 20160329_202539.jpg
 
I've been driving a 1980 D100/150 that's had a somewhat built 69 440 transplanted in place of the factory slant 6 and bolted to the factory 833 O/D.

I've done plenty of "spirited" driving.

It's fine.

I personally would not power shift any transmission into overdrive.

When driving hard, I like to think of the shift pattern as a three speed with a better 1-2 throw.

Stay in 1:1 until you feel like relaxing, then shift to O/D and cruise.
 
This is my PERSONAL overdrive experience from 1978. My 77 Volare Road Runner I bought new off the lot with a 318 2 bbl and overdrive tranny. After about 3000 miles the tranny would lock up in gear between shifts. I had to pull over to the side of the road and whack the shifter around to get it out of gear. It happened multiple times. Eventually I swapped it out for a proper 4 speed. I'm sure after all of these years someone can chime in and tell me what was wrong but that was my experience with a factory new OD gearbox.

Greg
 
Greg55_99 said:
This is my PERSONAL overdrive experience from 1978. My 77 Volare Road Runner I bought new off the lot with a 318 2 bbl and overdrive tranny. After about 3000 miles the tranny would lock up in gear between shifts. I had to pull over to the side of the road and whack the shifter around to get it out of gear. It happened multiple times. Eventually I swapped it out for a proper 4 speed. I'm sure after all of these years someone can chime in and tell me what was wrong but that was my experience with a factory new OD gearbox.

Greg
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That was likely in the shifter itself or the linkage. Doubtfully bent shifter fork because by then they were made of steel I believe. My point is more these are economy Transmissions built for economy cars and why would you want to build a high-performance motor and put an economy transmission thats Geared for economy? Like the previous poster just said it would probably work just great first second and third pretty much the same but you'd probably want to be a bit more careful using the overdrive gear with a high performance motor.
 
Greg55_99 said:
This is my PERSONAL overdrive experience from 1978. My 77 Volare Road Runner I bought new off the lot with a 318 2 bbl and overdrive tranny. After about 3000 miles the tranny would lock up in gear between shifts. I had to pull over to the side of the road and whack the shifter around to get it out of gear. It happened multiple times. Eventually I swapped it out for a proper 4 speed. I'm sure after all of these years someone can chime in and tell me what was wrong but that was my experience with a factory new OD gearbox.

Greg
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Most of the times when this happened, it was because one of the fingers of the lever on in interlocking lever on th side cover would snap off. It was a pisser because they would still shift most of the time, but every once in a while, the lever would get out of line and not shift. The best fix was to either beef up the levers in the side cover (done many of them) or just change out to a ball and detent cover.
 
Simple Logic that the mainshaft turns in any gear, it is what turns the driveshaft. The only time it does not turn, is in neutral. I love the O/D, but hesitated to recommend because of the 500 ft lb of torque. That is where the factory went with the 18 spline input shaft. I do not have anything in that range. So I do not have first hand experience. The O/D is not a cheap or cheaply made transmission. The early ones are very good but did get cheaper as time went on. The best thing to do to make them stronger is to reduce the float, I call it slop, by bushing the aluminum main housing or just replace the main housing with a cast iron housing with the press fit countershaft bores and standard countershaft. The theoretical locked input gear seams irrelevant in the practical world. I can cruise all day long at 70-80 MPH with mine and it is as smooth as my A833 4 speed.
 
I figured on using 1st,2nd @ 3rd for the occasional race but not 4th or,od under power. As far as Why? Simple,,,16 to 20 mpg in a light A body, instead of 8 to 10. The opportunity to drive cross country at highway speeds @ 2000 rpm,also see mileage. I'm not building a garage or trailer queen. I'm partial to mopar. Always was when younger. Gas was .69 cents a gallon then. If I can't create a combo like I want,I'll just sell he car and do something else... But thanks everyone for all the advice. Once my "direction" is figured out,I'll start buyin or sellin stuff.
 
cuda620 said:
I figured on using 1st,2nd @ 3rd for the occasional race but not 4th or,od under power. As far as Why? Simple,,,16 to 20 mpg in a light A body, instead of 8 to 10. The opportunity to drive cross country at highway speeds @ 2000 rpm,also see mileage. I'm not building a garage or trailer queen. I'm partial to mopar. Always was when younger. Gas was .69 cents a gallon then. If I can't create a combo like I want,I'll just sell he car and do something else... But thanks everyone for all the advice. Once my "direction" is figured out,I'll start buyin or sellin stuff.
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If you are not going to beat on it I would use the OD box. As long as you don't slam it into 4th (which is ironically, 3rd gear inside the trans!!!!!!!) you will probably never hurt it.

Because of tech increased trans speed when in OD I would use, at a minimum the very best 75w90 100% SYNTHETIC gear oil in. Don't be afraid to put a pint or pint and a half more oil in it. If you can find it, I would use 75w140 gear oil in the trans, as long as it's 100% SYNTHETIC.

You won't hurt it with the higher grade oil.

Keep us posted. I hope you do it.
 
IF it will handle a bigblock,then I will. I'm planning on driving this thing alot 6-8 months a year. I want to use it or its a waste of time to me. That also means if I want to do a 2000 mile road trip,it needs to,,, and not at 60mph. The mopar overdrive,which I've never used and no nothing about seems like a less expensive route. 30 years ago,when I had my 68 cuda,70 cuda,71 cuda,68,69,70,and 73 Chargers. I was building mopars using the Direct Connection books alot. All 383's and 440's. back then the mopar overdrive was somethig you avoided.... Gas was much cheaper too,,,as were the cars. I kick myself repeatedly. Now I gotta find parts. So to understand, I can abuse ,,,sometimes,,1st,2nd @ 3rd,but don't slam od,just cruise with it.,,?
 
cuda620 said:
IF it will handle a bigblock,then I will. I'm planning on driving this thing alot 6-8 months a year. I want to use it or its a waste of time to me. That also means if I want to do a 200 mile road trip,it needs to,,, and not at 60mph. The mopar overdrive,which I've never used and no nothing about seems like a less expensive route. 30 years ago,when I had my 68 cuda,70 cuda,71 cuda,68,69,70,and 73 Chargers. I was building mopars using the Direct Connection books alot. All 383's and 440's. back then the mopar overdrive was somethig you avoided.... Gas was much cheaper too,,,as were the cars. I kick myself repeatedly. Now I gotta find parts. So to understand, I can abuse ,,,sometimes,,1st,2nd @ 3rd,but don't slam od,just cruise with it.,,?
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Correct - just a regular bellhousing is just fine for the street. Just use arp bolts for the flywheel and clutch.
 
try and find the cast iron main case instead of the aluminum one. with the iron case you can beat on it and it will live within reason. Junk the interlocking side cover and put a ball and detent earlier cover on it. Take dremel and cut nubs off steel forks and you should be okay. like yellow rose and j par stated no 4th gear abuse.
 
OP
The O/D box has terrible ratios for hi-rpm use.The spreads are ridiculous for that.
The ratios are 3.09-1.67-1.0-.71/.73. The spreads are 54%,60% and od. What that means is that during a shift at 6500, the rpm will fall to those percents; so 3510 in first and 3900 into direct (3rd). The little 340 will fall on it's face, to drag itself from those rpms, unless you build it specially for that spread. with 4.30s it will have to pull from 75mph to trap speed. That is a long hard pull,starting at 3900, some 600 to 800 below peak torque. And first gear at 3.09 x 4.30 =13.29, is equivalent to running a 5.00 with a 2.66 low tranny. So at the track you will shift into 2nd,pretty much right out of the gate and have 2 gears to run the qt, outshifting 2nd at 75 mph.Again a long hard pull.
I ripped the MD teeth off one of those gearsets at about 400 to 440 ftlbs, and I wasn't even using all of them.
And I shredded two OD gears.One with a teener.
The BB has so much inherent torque, you wouldn't have to shift at 6500. But you already know it's the wrong tranny for the high reving 340, so IMHO; fugetabowd that O/D box, for your stated useage..

Now, if you would consider a 360 with a GV, I can tell you that is really really sweet with a cam of 220 to 230 @050, and up to 3.91s! Gear-splittin is a blast!!
 
AJ/FormS said:
OP
The O/D box has terrible ratios for hi-rpm use.The spreads are ridiculous for that.
The ratios are 3.09-1.67-1.0-.71/.73. The spreads are 54%,60% and od. What that means is that during a shift at 6500, the rpm will fall to those percents; so 3510 in first and 3900 into direct (3rd). The little 340 will fall on it's face, to drag itself from those rpms, unless you build it specially for that spread. with 4.30s it will have to pull from 75mph to trap speed. That is a long hard pull,starting at 3900, some 600 to 800 below peak torque. And first gear at 3.09 x 4.30 =13.29, is equivalent to running a 5.00 with a 2.66 low tranny. So at the track you will shift into 2nd,pretty much right out of the gate and have 2 gears to run the qt, outshifting 2nd at 75 mph.Again a long hard pull.
I ripped the MD teeth off one of those gearsets at about 400 to 440 ftlbs, and I wasn't even using all of them.
And I shredded two OD gears.One with a teener.
The BB has so much inherent torque, you wouldn't have to shift at 6500. But you already know it's the wrong tranny for the high reving 340, so IMHO; fugetabowd that O/D box, for your stated useage..

Now, if you would consider a 360 with a GV, I can tell you that is really really sweet with a cam of 220 to 230 @050, and up to 3.91s!
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If he was worried about gear splits, he wouldn't be considering an OD box in the first place.

He wants to cruise down the road. That box will do it. He wants to beat on it a bit, not set a nation record, or drop the laundry on Daddy Dave or Chief.

You should be good to go. Just use the BEST gear oil you can find, preferably in 74w140
 
yellow rose said:
If he was worried about gear splits, he wouldn't be considering an OD box in the first place.

He wants to cruise down the road. That box will do it. He wants to beat on it a bit, not set a nation record, or drop the laundry on Daddy Dave or Chief.

You should be good to go. Just use the BEST gear oil you can find, preferably in 74w140
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Rose
I mean no disrespect, when I say
I guess we live in different worlds, cuz in mine, we don't build strokers or BBs to cruise around with, or tour.
But you are absolutely right; if that is his intent, "that box will do it".
And I also think that for cruising and touring with a stroker or BB, a 3.23/3.55 rear will do it, and then there would be no need for an O/D in the first place

Op
if that IS your intent, to cruise or tour,you better disconnect the secondaries, in case you forget. I have three O/D trannys here that say a hot 360 is too much for them.When the teeth peel off, there's a good chance that the pieces will take out the cluster as well, and possibly more. I always kept a spare tranny on hand, so as not to risk walking the summer away.I have one left. But I'm no longer running those.
 
AJ, I'm not opposed to running a GVO if it becomes my best option. I plan on building either a stroked smallblock or 400. I'd run my 440,but have to change or give up things I'm not willing to. 3:55's and 75 mph don't work without an OD. I'm gonna build a hi perf engine and maximize my street mpg with some type of od. Listening to everyone's ideas here. Their all good ones. Just figuring best route for my build. Thanks Everyone.
 
I dunno about your best option as it pertains to a manual.
But I am sure the 833 O/D is not it.
But heres something to think about. It sounds to me like your biggest concerns are to keep the revs down at 75mph, and you really want a manual tranny. If this is right, and you had a small block,then you would really need a 5 speed, to get back some off-the-line, giddy-up. But with a lot of cubes, comes a lot of torque, so getting off the line is less of an issue. Depending on your horsepower level desired, versus reality, there is/are other options.
If you are willing to go easy on the cam, I can offer this suggestion, which is what I have settled on; The 3.09 low/Direct 4th box with a GV behind it, and 3.55s.I will use Bold numbers to indicate GV ratios.
The ratios are 3.09-1.92-1.40-1.00-.78,
With 28 inch tires. this will work out to about 2500rpm at 75mph.
The starter gear will be 3.09x3.55 =10.97 which with the standard box is about equivalent to; 10.97/2.66 = 4.12s, not too shabby.
The splits are 62%,73%,71% and 78% into od.This means outshifting at say 6300, the rpms will drop to; 3960into 2nd, 4663into third,and 4535into fourth.The big engine will have no trouble pulling outta these drops. The powerband requirement will thus be about 6300 less about 4600 =1700 rpm. You won't need a whole lotta cam for this.
So let's look at this;
Big engine = big torque, so don't need big gears to get off the line; so that 10.97 starter will be more than, ok,
and tight powerband means small cam is ok. Tranny splits are excellent,
starter gear is excellent,
overdrive gear is excellent.
You might be looking at the 1-2 split. The drop is to 3960, and it happens at 48 mph. Fair enough that's a bit of a stretch.So I'll tell you a secret; The GV will take full power, and can be used as a splitter. If you split the 1-2, the ratios are 3.09-2.41-1.92-1.40-1.0-.78. See anything you like there? Heckyeah 6 gears!
Ok, now, the rpm drop into 1od is .78, so from 6300 will drop in at 4914 Whoa!. And 1od into 2nd will be .80, so from 6300 will drop in at 5019Sweet! So now you have the powerband down to 1500 and change.
Now if you wanna track this car expect to crank out about 115 or better, then you will need a final drive of 4.70 to perhaps 4.30s. Well, 3rd is 3.55x 1.4 = 4.97 so that's a little steep. But 3.23s and 3rd is 3.23x 1.4 =4.52 Right smack in the middle. So, back up the bus. Since we have Gear-splitting capability, why not pitch the 3.55s and just compromise with the 3.23s? What? you ask who tracks with 3.23s?
Well check it out; Why not split 1-2, and 2-3? This makes just one pull on the stick and 2 electric lightning GV shifts. Interested?
The ratios are 3.09-2.41-1.92-1.49. and the rear is a 3.23.The starter gear is 9.98(equivalent to a regular box with 3.75s). The trap gear is 1.49x3.23=4.81(a bit out there). The hiway gear is 3.23 x .78 =2.52, making 75=2267rpm.
So what have you got? Well it won't 60ft like lightning. and that 4.81 FD will make 115mph at 6639rpm. But hey you could use third. Which is 1.4x 3.23=4.52, dropping that 115 to 6240! leaving you a lot of headroom! 6500 would get you 120mph.

There are two tricks to making this work; 1) a willingness to compromise your 60ft, and 2) a willingness not to shoot for the moon as regards a camshaft.These are real options for a streeter.
I have posted the gear ratios, so that you can play the numbers for yourself, and decide if it's for you. The splits are so tight, you will put a lot of average horsepower down.Keep in mind that there are 5speed options out there right now for a pretty good price.

I have been running the above combo with 3.55s and a 367 cuber in a 3650# raceweight 68Barracuda, set up for street, for over 12 years now. In 2004,she went 93 in the 1/8, the one and only successful run it ever made.I have no idea what that translates to in qt trap, but to me it was damfast.
I feel that two splits and tight ratios,in my combo are worth at least one or two cam sizes. My car is faster with this combo and a 230*(276 advertised) cam than it was with the 292/508 (maybe 248@050)and a regular 4speed.That's at least 3 cam sizes. And the 230* is sooooo much sweeter on the street.
I know my combo is just a little367, but it seems to act big.With the legal speed limit here being 62(100kph), and my 27 inch tires, cruising is 2137 with 3.55s.
 
I didn't see anyone mention this yet, but one of the week areas of the 833OD is that the counter shaft is floating instead of a pressed fit like the regular 833. You can get the case bushed and get a countershaft for a regular 833 and that will increase strength.
 
aj/forms , you can't beat the math . with the working knowledge of that is more than theory . so looks as the early a body gears are the best with a gv for a 340 duster or an early 340'd barracuda .
 
I am gonna use my truck OD 4 speed in the same manner you plan to use yours. In my rat truck sometimes driving everyday. Just cruisin around. That's all. I've never once thought it would not hold up.
 
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