How to identify a close ratio to wide ratio 833

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joes68340s

joes68340s

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I have an early 66 to 67 4 spd I was wondering how I can tell what ratio trans it is. I'm running a 3.08 rear so it tends to buck in 1st and 2nd at low speeds.
 
shift it in first gear ( rear lever pulled to the rear) and count how many revs of the input it takes to make the output rotate once
 
joes68340s said:
I have an early 66 to 67 4 spd I was wondering how I can tell what ratio trans it is. I'm running a 3.08 rear so it tends to buck in 1st and 2nd at low speeds.
Click to expand...
have to remove side cover, count teeth on cluster and input shaft. also count teeth on first gear and cluster shaft. this is how mopar suggest correct ratio answers. main shaft, is 2.66 set, 24 0n input, 29=3rd, 34=2nd,35= 1st.3.09 set, 22 input, 27= 3rd,32=1st. hope this helps.
 
joes68340s said:
I have an early 66 to 67 4 spd I was wondering how I can tell what ratio trans it is. I'm running a 3.08 rear so it tends to buck in 1st and 2nd at low speeds.
Click to expand...
I may be wrong but
perfacar said:
have to remove side cover, count teeth on cluster and input shaft. also count teeth on first gear and cluster shaft. this is how mopar suggest correct ratio answers. main shaft, is 2.66 set, 24 0n input, 29=3rd, 34=2nd,35= 1st.3.09 set, 22 input, 27= 3rd,32=1st. hope this helps.
Click to expand...
To be honest now I'm not sure there was a close ratio in 66, 67.
 
If its an A body trans and has a slip yoke tail shaft, it should have a 2.66 first gear. 1966 till 1970 A bodies have 2.66 first gears and are wide ratio trans, 71 to 74 have 2.47 first gears which are the close ratio trans in the A bodies. The trans ratio you need is the 3.09 first gear which came in the 64 and 65 A body cars with slant 6 and 273 with the flange on the tail shaft, also made the 3.09 first in 73 and 74 only in the 318 Dart Sport and Duster with the 2.73 axle ratio. The overdrive trans from 1975 to 1980 use the 3.09 first gear too.
 
19DART66 said:
If its an A body trans and has a slip yoke tail shaft, it should have a 2.66 first gear. 1966 till 1970 A bodies have 2.66 first gears and are wide ratio trans, 71 to 74 have 2.47 first gears which are the close ratio trans in the A bodies. The trans ratio you need is the 3.09 first gear which came in the 64 and 65 A body cars with slant 6 and 273 with the flange on the tail shaft, also made the 3.09 first in 73 and 74 only in the 318 Dart Sport and Duster with the 2.73 axle ratio. The overdrive trans from 1975 to 1980 use the 3.09 first gear too.
Click to expand...
Thanks
 
joes68340s said:
I have an early 66 to 67 4 spd I was wondering how I can tell what ratio trans it is. I'm running a 3.08 rear so it tends to buck in 1st and 2nd at low speeds.
Click to expand...

It takes a pretty big street cam to buck in first. To buck in second you are either lugging it, need better gas, or your tune is way off.
You wanna talk about the tune first? Might save you hunting for a tranny......
There is only about 7% difference from the 2.47 to the 2.66. This is less than the difference from one rear chunk to the next, below 3.73s.
There is 16% difference between the 3.09 and the 2.66; but second,third, and fourth are the same. And outshifting the 3.09 will drop the rpm to lower than the 2.66 at the same rpm; so there is no cure here.
That means; if your tune is spot on, and your gas is top-quality, and you are not lugging it, then you have one of three options;
1) you need a bigger rear gear, or
2) you need a smaller cam,or carb, or
3) you will have to live with it.
I wanna talk about the tune,lol
 
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People keep posting the link to that Brewers page but it doesn't tell you which trany you might have just where the numbers they need are. Am I reading it wrong ?

Not to start another heated debate but... What flywheel are you using ?
 
AJ/FormS said:
It takes a pretty big street cam to buck in first. To buck in second you are either lugging it, need better gas, or your tune is way off.
You wanna talk about the tune first? Might save you hunting for a tranny......
There is only about 7% difference from the 2.47 to the 2.66. This is less than the difference from one rear chunk to the next, below 3.73s.
There is 16% difference between the 3.09 and the 2.66; but second,third, and fourth are the same. And outshifting the 3.09 will drop the rpm to lower than the 2.66 at the same rpm; so there is no cure here.
That means; if your tune is spot on, and your gas is top-quality, and you are not lugging it, then you have one of three options;
1) you need a bigger rear gear, or
2) you need a smaller cam,or carb, or
3) you will have to live with it.
I wanna talk about the tune,lol
Click to expand...
I know there is a problem with the tune. Carb needs cleaning and tuning. So I will start there. Thanks
 
mbaird said:
People keep posting the link to that Brewers page but it doesn't tell you which trany you might have just where the numbers they need are. Am I reading it wrong ?

Not to start another heated debate but... What flywheel are you using ?
Click to expand...

There no number outside telling what gear is use inside. But, the year of manufacture is a good hint what it's should be, if it's still stock
 
Aha! a 380Magnum
This engine comes with a 9.0 CR, 288/292/108(I think) cam. and an M1 Singleplane intake and is not for use with A/C. lol.
Question #1 is why are you hobbling it with a 3.08x2.66=8.19 starter gear?The minimum roadspeed with this combo is about 8 mph, an unless your tune is perfect, it WILL be jumpy.
That camand intake combo wants about an 11/1 starter, minimum 10/1. That would be 3.73s to 4.10s with the 2.66 low box.

So first things first; you need a perfect tune, then if still jumpy, get a different intake, then if still jumpy,get some bigger gears in the back. But 3.55s, say will only get your minimum roadspeed down to 6.8 mph,still with a perfect tune.So the next thing would be to get the 3.09 low box.This would get your minimum roadspeed down to 5.8 mph.
Are you seeing why guys run automatics with big cams?
So, you need to get the tune dialed in;JOB #1.Or spend a lot of money to move the jumpiness down 2.2 mph, can you hear me chuckling? See, That's what I did; I spent a lot of money to get the jumpiness down to 4 mph.

But first we need to talk a little more about second-gear jumpiness. This is highly unusual.
Question #2; At what rpm or roadspeed does this second-gear jumpiness take place?
Question #3; and yet TBA is the flywheel weight?

So where to start? That's easy I always start with the T-port sync.
 
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AJ/FormS said:
Aha! a 380Magnum
This engine comes with a 9.0 CR, 288/292/108(I think) cam. and an M1 Singleplane intake and is not for use with A/C. lol.
Question #1 is why are you hobbling it with a 3.08x2.66=8.19 starter gear?The minimum roadspeed with this combo is about 8 mph, an unless your tune is perfect, it WILL be jumpy.
That camand intake combo wants about an 11/1 starter, minimum 10/1. That would be 3.73s to 4.10s with the 2.66 low box.

So first things first; you need a perfect tune, then if still jumpy, get a different intake, then if still jumpy,get some bigger gears in the back. But 3.55s, say will only get your minimum roadspeed down to 6.8 mph,still with a perfect tune.So the next thing would be to get the 3.09 low box.This would get your minimum roadspeed down to 5.8 mph.
Are you seeing why guys run automatics with big cams?
So, you need to get the tune dialed in;JOB #1.Or spend a lot of money to move the jumpiness down 2.2 mph, can you hear me chuckling? See, That's what I did; I spent a lot of money to get the jumpiness down to 4 mph.

But first we need to talk a little more about second-gear jumpiness. This is highly unusual.
Question #2; At what rpm or roadspeed does this second-gear jumpiness take place?
Question #3; and yet TBA is the flywheel weight?

So where to start? That's easy I always start with the T-port sync.
Click to expand...
Lots of info there. It has a stock flywheel heavy. Car is built for autox at this point I'm going to work the tune as I know there are some issues.
 
AHA!, Autocross
Now we know why the 3.08s
Are you running mostly in first? cuz that's got to be hard on the mainshaft.

2.66 First x 3.08 rear gear =8.19 final-drive. You could get a similar ratio with
1.92Second x 4.30s out back=8.26
This would help get rid of the lowspeed jumpiness or at least move it down. The minimum roadspeed with 4.30s might be 5.6mph

As to your tune, I'll tell you a secret. The jumpiness is much diminished after you get the t-ports synced, with a minimum Idle-timing.By "retarding" the timing from what almost everybody says you need, the peak cylinder pressure comes later when the piston is a little further down the bore.And it is weaker. So it is transferred to the crank a little more softly.And so the jumpiness is smoothed out by the heavy flywheel.
I ran the 292/508/108 for a while, a long time ago. I ran it with just 14 to 16 degrees idle-timing. It was still a little jumpy with 3.55s and a 2.66 low. So I tried other ide-timings, but that 292 was not happy about that. So I bought a dash-mounted, dial-back, timing box, and started experimenting. Soon I found out, that I could retard the Idle-Timing to maybe 8* when it got jumpy, and that would smooth her out enough to drive a little slower. Then, when the parade was over, I could simply dial the advance back up.
But that cam and I just could not become friends, so one day I had opportunity to sell it, and I couldn't yank it out fast enough!
 
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AJ/FormS said:
AHA!, Autocross
Now we know why the 3.08s
Are you running mostly in first? cuz that's got to be hard on the mainshaft.

2.66 First x 3.08 rear gear =8.19 final-drive. You could get a similar ratio with
1.92Second x 4.30s out back=8.26
This would help get rid of the lowspeed jumpiness or at least move it down. The minimum roadspeed with 4.30s might be 5.6mph

As to your tune, I'll tell you a secret. The jumpiness is much diminished after you get the t-ports synced, with a minimum Idle-timing.By "retarding" the timing from what almost everybody says you need, the peak cylinder pressure comes later when the piston is a little further down the bore.And it is weaker. So it is transferred to the crank a little more softly.And so the jumpiness is smoothed out by the heavy flywheel.
I ran the 292/508/108 for a while, a long time ago. I ran it with just 14 to 16 degrees idle-timing. It was still a little jumpy with 3.55s and a 2.66 low. So I tried other ide-timings, but that 292 was not happy about that. So I bought a dash-mounted, dial-back, timing box, and started experimenting. Soon I found out, that I could retard the Idle-Timing to maybe 8* when it got jumpy, and that would smooth her out enough to drive a little slower. Then, when the parade was over, I could simply dial the advance back up.
But that cam and I just could not become friends, so one day I had opportunity to sell it, and I couldn't yank it out fast enough!
Click to expand...
that's good info I have been tying to get max timing out of it as that's what I'm used to for drag racing. I noticed that the timing mark jumps a lot at idle between 5 and 6 degrees. Engine idles fine but the minute I try to take off it just wants to bog and its jumpy at 2000 rpm and under. I can see I'm fighting this. I do want to increase the rear gear but I need to change over to 8 3/4. Thanks for your info.
 
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