geared way too low

[xratt]

im new to the forum, so bear with me. I just bought a 1966 c10, with a 350 sb, and trans. out of a 1982 chevy truck installed in it. They did the swap and sold off the project. So I have a lot to figure out. I will be back with lots of questions. I'm sure all these have been asked before, I just did not find the threads to answer this stuff yet, you can refer me to them if its easier.

First off, it has the 350 sb, and i think its a th400, i still have to verify that. The stock rear end is still in the truck. The original motor was the straight 6 and a 3 speed trans. With the new motor and trans, it shifts super early.
I will hit 3 gear by 20 MPH. So the motor revs out trying to go 55 and 60. Is this a rear end deal, geared super low? Or is the new trans not hooked up properly? I already found what i believe to be the kick down cable cut and hanging under the truck. If it is the rear end gearing, is it easier to regear it with different gears? Or just replace the whole rear end? Im assuming the 1982 rear end would work best. I need as narrow rear end as possible,cause he truck sits real low and the tires almost hit the bed now.

So any help you guys can give would be wonderful.

I will have plenty more questions as this truck progesses, so dont get tired of me asking dumb questions. I plan on keeping this truck a long time, as soon as i get it running decent it will be my daily driver

[ERASER5]

The 66 rear will be narrower than an 82.

To check the gearing do this.


1. Get ready to lift the truck. Flat ground, chock the front tires, and all that.

2. Put the trans in neutral and lift 1 rear tire.

3. Spin the tire. Does it spin?
Yes: Open differential.
No: Limited Slip
So far so good. Now for the ratio the easy way.

There are two methods. The first is for the open differential (that's why we checked).
OPEN DIFF METHOD:
1. Look at the valve stem and note were it is.
2. Look at the drive shaft. Make a mark on it. Chalk is good.
3. Put your hand on the valve stem area and rotate the tire exactly 2 times while counting the drive shaft rotations. Remember this number.

LIMITED SLIP METHOD:
1. Jack up both rear tires.
2. Look at the drive shaft. Make a mark on it. Chalk is good.
3. Put your hand on the valve stem area and rotate the tire exactly 1 time. while counting the drive shaft rotations. Remember this number.

You must use the correct method for your differential.

You came up with only a very few possible numbers and you only have to be within a 1/4 turn, so it is easy to get it right.

2-3/4 turns -- 2.73:1 Unlikely
3+ turns -- 3.08:1 Lots of those
3 1/2 turns -- 3.54:1 Could be
3 3/4 turns -- 3.73:1 Lots of those too.
4 turns -- 4.10:1 Maybe
4 1/2 turns -- 4.52:1 Unlikely

The spider gears in the open diff take up 1/2 of the tire rotation. That is why you need to go 2 turns for an open diff.

Lots of guys do a lot more rotations. That is just not necessary. My method (not really mine, I was taught this long ago) is easy, fast, and not very messy. You can always get greasy later.

[joe231]

If the trans is a TH400 there is no kick-down cable, they have an electric kick down, the TH350 will have a kick-down cable...easiest way to ID it is by the pan shape and number of bolts.
check this LINKY
or this LINKY

[Captainfab]

A 6 cyl, 3 speed truck could very well have 4.10 gears which is a bit on the low side for highway cruising. What size tires are on your truck? The diameter of the tires will play a part in the overall engine speed.

And welcome to the board

[protrash64]

from AZ. Will be nice to see some pics and hear about the progress.

[xratt]

I will check the gearing as soon as i get it back from the shop. It quit running, and i only have onstreet parking here, so off to my buddies shop it went. New trans gasket, filter and service, new oil pan gasket, new rear main seal, full carb rebuild, and tune, and set the timing.

Should have it back today, I hope. I cant remember the exact tire size, something near 165/65/15, nothing crazy, a little wider then stock rims. I have thought about going with a narrower, taller tire. The tires now hit the insides of the bed when it lowers all the way down. The truck sits on air bags, and has a c-notched frame in the rear. The bumper almost hits the ground when its down, but the tires will not roll cause they sit on the inner bed. So other then running gear, i have lots of other stuff to figure out.

Thanks everyone for the information and advice, i will be back with lots more questions and more pics.

[xratt]

[MacAttack]

Originally Posted by Captainfab

The diameter of the tires will play a part in the overall engine speed.

A set of these might help....



Mac.

[joe231]

duuude!!!
that is sweet!!
what is the suspension set up on it? c-notch or step notch in the rear? Trailing arms?
How about pics of the suspension too?

[c10Mang]

Nice!! More pix!

[4dranch]

Welcome from west Tn.
Very slick rig..

[c10Mang]

On another note, my buddy put these http://www.automotiveconcepts.net/st...medium=organic tips on the same setup you have. They look sick

[joe231]

talk about tall gearing

[1Bad62Pro/Street]

Originally Posted by xratt

im new to the forum, so bear with me. I just bought a 1966 c10, with a 350 sb, and trans. out of a 1982 chevy truck installed in it. They did the swap and sold off the project. So I have a lot to figure out. I will be back with lots of questions. I'm sure all these have been asked before, I just did not find the threads to answer this stuff yet, you can refer me to them if its easier.

First off, it has the 350 sb, and i think its a th400, i still have to verify that. The stock rear end is still in the truck. The original motor was the straight 6 and a 3 speed trans. With the new motor and trans, it shifts super early.
I will hit 3 gear by 20 MPH. So the motor revs out trying to go 55 and 60. Is this a rear end deal, geared super low? Or is the new trans not hooked up properly? I already found what i believe to be the kick down cable cut and hanging under the truck. If it is the rear end gearing, is it easier to regear it with different gears? Or just replace the whole rear end? Im assuming the 1982 rear end would work best. I need as narrow rear end as possible,cause he truck sits real low and the tires almost hit the bed now.

So any help you guys can give would be wonderful.

I will have plenty more questions as this truck progesses, so dont get tired of me asking dumb questions. I plan on keeping this truck a long time, as soon as i get it running decent it will be my daily driver

I don't think your rear end being a low gear is the problem.
It should be around 3.90--4.09.....I think I will have to check my book.
My 1/2 ton 62 had a 3.90--4.09 final gear ratio. Check your rear end plate.
You should have plenty of touque out of that 350.
What is the stall on your Torque Converter?
It may be the Governor, Vacuum Modulator, Throttle Cable

These three components are important in the non-computerized transmissions. They provide the inputs that tell the transmission when to shift. The Governor is connected to the output shaft and regulates hydraulic pressure based on vehicle speed. It accomplishes this using centrifugal force to spin a pair of hinged weights against pull-back springs. As the weights pull further out against the springs, more oil pressure is allowed past the governor to act on the shift valves that are in the valve body which then signal the appropriate shifts.

Of course, vehicle speed is not the only thing that controls when a transmission should shift, the load that the engine is under is also important. The more load you place on the engine, the longer the transmission will hold a gear before shifting to the next one.

There are two types of devices that serve the purpose of monitoring the engine load: the Throttle Cable and the Vacuum Modulator. A transmission will use one or the other but generally not both of these devices. Each works in a different way to monitor engine load.
The Throttle Cable simply monitors the position of the gas pedal through a cable that runs from the gas pedal to the throttle valve in the valve body.
The Vacuum Modulator monitors engine vacuum by a rubber vacuum hose which is connected to the engine. Engine vacuum reacts very accurately to engine load with high vacuum produced when the engine is under light load and diminishing down to zero vacuum when the engine is under a heavy load. The modulator is attached to the outside of the transmission case and has a shaft which passes through the case and attaches to the throttle valve in the valve body. When an engine is under a light load or no load, high vacuum acts on the modulator which moves the throttle valve in one direction to allow the transmission to shift early and soft. As the engine load increases, vacuum is diminished which moves the valve in the other direction causing the transmission to shift later and more firmly.

If a non computer-controlled transmission is shifting too early or too late, it may require an adjustment to the throttle cable. Since throttle cables rarely go out of adjustment on their own or due to wear and tear, these mis-adjustments are usually due to other repair work or damage from an accident. If the vehicle has a vacuum modulator instead of a throttle cable, there is an adjustment that can be made using an adjustment screw in some modulator designs. In vehicles with modulators, however, it is very important that there are no vacuum leaks and the engine is running at peak efficiency. Engine vacuum is very sensitive to how well the engine is running. In fact, many technicians use a vacuum gauge to diagnose performance problems and state-of-tune. Many problems that seem to be transmission problems disappear after a tune-up or engine performance related repair was completed.

In some older transmissions, bands can be adjusted to resolve "slipping" conditions. Slipping is when an engine races briefly when the transmission shifts from one gear to the next. There are no adjustments for clutch packs however.

Not an expert.......but just a thought.


http://en.wikipedia.org/wiki/Turbo-Hydramatic

[xratt]

Finally got some more work going on the truck. Counted the rear end cover bolts, its a 12 bolt rear end. Measured the tire rotation. Came up with 3.73 gears. So I know I want to lower that gear. The trans shifts in all three gears just fine, just seem like it needs a 4th gear. But the trans is a three speed. Doing 55 the motor is just screaming. Next question, change the ring gear or find a different rear end. Also discovered this truck has 6 lug to 5 lug adapters. Don't like that so I'm hunting some 6 lug rims. Still working on wiring issues and having a air bag problem in the front end. Unless it's inflated all the way the front end sits crooked. Passenger side is way lower. I plan on tearing that apart this weekend. More pics coming. Pics of c-notch and others. Thanks so much for everyones help.

[1Bad62Pro/Street]

Originally Posted by 1Bad62Pro/Street

I don't think your rear end being a low gear is the problem.
It should be around 3.90--4.09.....I think I will have to check my book.
My 1/2 ton 62 had a 3.90--4.09 final gear ratio. Check your rear end plate.
You should have plenty of touque out of that 350.
What is the stall on your Torque Converter?
It may be the Governor, Vacuum Modulator, Throttle Cable

These three components are important in the non-computerized transmissions. They provide the inputs that tell the transmission when to shift. The Governor is connected to the output shaft and regulates hydraulic pressure based on vehicle speed. It accomplishes this using centrifugal force to spin a pair of hinged weights against pull-back springs. As the weights pull further out against the springs, more oil pressure is allowed past the governor to act on the shift valves that are in the valve body which then signal the appropriate shifts.

Of course, vehicle speed is not the only thing that controls when a transmission should shift, the load that the engine is under is also important. The more load you place on the engine, the longer the transmission will hold a gear before shifting to the next one.

There are two types of devices that serve the purpose of monitoring the engine load: the Throttle Cable and the Vacuum Modulator. A transmission will use one or the other but generally not both of these devices. Each works in a different way to monitor engine load.
The Throttle Cable simply monitors the position of the gas pedal through a cable that runs from the gas pedal to the throttle valve in the valve body.
The Vacuum Modulator monitors engine vacuum by a rubber vacuum hose which is connected to the engine. Engine vacuum reacts very accurately to engine load with high vacuum produced when the engine is under light load and diminishing down to zero vacuum when the engine is under a heavy load. The modulator is attached to the outside of the transmission case and has a shaft which passes through the case and attaches to the throttle valve in the valve body. When an engine is under a light load or no load, high vacuum acts on the modulator which moves the throttle valve in one direction to allow the transmission to shift early and soft. As the engine load increases, vacuum is diminished which moves the valve in the other direction causing the transmission to shift later and more firmly.

If a non computer-controlled transmission is shifting too early or too late, it may require an adjustment to the throttle cable. Since throttle cables rarely go out of adjustment on their own or due to wear and tear, these mis-adjustments are usually due to other repair work or damage from an accident. If the vehicle has a vacuum modulator instead of a throttle cable, there is an adjustment that can be made using an adjustment screw in some modulator designs. In vehicles with modulators, however, it is very important that there are no vacuum leaks and the engine is running at peak efficiency. Engine vacuum is very sensitive to how well the engine is running. In fact, many technicians use a vacuum gauge to diagnose performance problems and state-of-tune. Many problems that seem to be transmission problems disappear after a tune-up or engine performance related repair was completed.

In some older transmissions, bands can be adjusted to resolve "slipping" conditions. Slipping is when an engine races briefly when the transmission shifts from one gear to the next. There are no adjustments for clutch packs however.

Not an expert.......but just a thought.


http://en.wikipedia.org/wiki/Turbo-Hydramatic

Hey Bud,
I just replied to your PM.
What is your Engine specs:
Heads/Cam/Crank/Compression Ratio & the Stall of your Torque Converter? For instance I have a 2,800 stall converter on my truck. The way I built my engine setup... I needed a 2,800 stall convetor for the street. You shouldn't have no more than 3,000 stall for the street. It also sounds like it has a Shift Improver Kit as well. That's what I have as well in my 62. She will bark the tires off quick.....
http://www.jegs.com/p/B-M/B-M-Shift-...47997/10002/-1
It also sounds like you don't have a stock engine by what you tell me about the cam. How many horses is she putting out? Is it a STROKER?
One of the things when building an engine is to consider stall speed, matching a converter to cam size and rear axle ratio.
This link can help you.
http://allfordmustangs.com/forums/4-...rter-info.html
http://67-72chevytrucks.com/vboard/s...d.php?t=327764

[joe231]

just because the rear cover has 12 bolts doesn't make it a 12 bolt, 10 and 12 bolt refers to the number of bolts that hold the ring gear on the GM corporate rear ends. there are many other ends such as Eaton and Dana to name a couple.

[protrash64]

I agree with Cap'n Fab....if you're searchin' out new wheels, throwing some larger diameter tires on there could be a fairly cost effective way of lowering your ratio.

[chucks1967]

Keep em low! Just cruse around town and smoke em! I would love to have 4:10's with a locker. but I just cruse around town, never get on the hwy.

[xratt]

Since i just bought this truck, i have to figure out all these things about the motor, i know its a 350, Edelbrock carb, and Edelbrock intake manifold, Stock exhaust manifolds. Seems to have a farily big cam. Lopes bad at low idle, then shuts off. But have no idea on Bore, Stroke, Type of torque converter, or transmission alterations. So I will post more on these as i figure them out. I did check with an exhaust shop today about redoing the pipe, its real close to the ground. I keep hitting it on the ground. So Im taking it in Monday for new duals, with dual cherry bombs. It has a single cherry bomb now and I'm surprised how quiet it is. Im also going to start calling around a few head shops on prices for new valve guide seals, it definately smokes alot when i first crank it. And started to boog and load up when it idles for a minute or two. I think it's oil leaking down from the heads causing this. Just more stuff to figure out. Also, a new question, to do with the torque converter, when i have it in drive and the brake on at a stop light, the truck pulls real hard against the brakes. Have to keep my foot planted on the pedal hard. If i idle the motor down any to help this the motor lopes real bad and dies, due to the cam. Any fixes or ideas on this?

[Captainfab]

Originally Posted by xratt

Since i just bought this truck, i have to figure out all these things about the motor, i know its a 350, Edelbrock carb, and Edelbrock intake manifold, Stock exhaust manifolds. Seems to have a farily big cam. Lopes bad at low idle, then shuts off. But have no idea on Bore, Stroke, Type of torque converter, or transmission alterations. So I will post more on these as i figure them out. I did check with an exhaust shop today about redoing the pipe, its real close to the ground. I keep hitting it on the ground. So Im taking it in Monday for new duals, with dual cherry bombs. It has a single cherry bomb now and I'm surprised how quiet it is. Im also going to start calling around a few head shops on prices for new valve guide seals, it definately smokes alot when i first crank it. And started to boog and load up when it idles for a minute or two. I think it's oil leaking down from the heads causing this.

Sounds like carb problems to me.

Originally Posted by xratt

Just more stuff to figure out. Also, a new question, to do with the torque converter, when i have it in drive and the brake on at a stop light, the truck pulls real hard against the brakes. Have to keep my foot planted on the pedal hard. If i idle the motor down any to help this the motor lopes real bad and dies, due to the cam. Any fixes or ideas on this?

Sounds to me like you need a stall converter.

[xratt]

I dont need to build a fast truck. I plan on drivnig this thing everyday, and need a trusty ride. So getting things back to stock or low maintenance and interstate friendly is important. I have to be able to drive this thing around town and make it to Turkey Day in Daytona every year.

[1Bad62Pro/Street]

Originally Posted by xratt

I dont need to build a fast truck. I plan on drivnig this thing everyday, and need a trusty ride. So getting things back to stock or low maintenance and interstate friendly is important. I have to be able to drive this thing around town and make it to Turkey Day in Daytona every year.

Wow......
Sounds like they didn't have the setup right at all. Or just started it, and didn't finish it right. Hmmmmmmm.
Does it have a HEI Distributor in it? MSD? Have you checked the timing?
Wonder if it is a lockup convertor.
Man.... Would like to know the lope on that cam. That rearend would be great, but it has a 3.08 gear in it. If might be sluggish for that motor if it thumping and bumping like that. If it was built mild or stock the rear end would be perfect. I had a mild 283 in my truck along with that 8.8. Was great on gas. I had a buddy that had a 93 GT that he put a wild 351 Windsor in it, and when he would put in drive with the brake on it would bow up something fierce, and would run on the road right either. Think he a 3,000 stall convertor in his AOD with a trans brake. Man I can't remember what we did.....

Well Bud,
I will ask my dad tomorrow and PM you with an answer.

[xratt]

The motor is a 350 suppose to be out of a 1982 c10. HEI dist. Just had the whole motor tuned up, rebuilt the carb. new rear main seal, oil pan gasket, trans pan gasket and filter replaced. set the timing. new water pump, replaced alternater, battery. New plugs, wires, cap, and rotor. it seems to still be going though some oil, just did fresh oil and filter, and the oil seems lower after a week of driving. Puffs white smoke pretty bad

[1Bad62Pro/Street]

OK,
Me and Pops talked today. I have learned alot from him from the years. Hot Rod Grand Master.

It sounds like the fellas your bought from from put a radical, rough idle cam in the motor and did not set the engine and trans to compinsate.
We don't know what kind of Heads are on there either.
It's your Torque Convetor Bud. You have a stock convetor, and you need a higher stall for that cam to compinsate. What stall do I need? Well we have to know the duriation of that cam. If you put in drive with your foot on the brake, and the truck is pulling foward then that what it is.
The camshaft will affect the torque curve of the engine, which will affect the performance of the converter. For example if your 350 cid engine produces 230 lb.ft. of torque at 2400 rpm a 2,000 stall converter will produce 2,000 rpm stall speed. If you install a 268-degree cam into this engine you will raise the torque curve and at 2400 rpm your engine will produce less torque. Thus the 2000 stall converter will only stall at 1800 or less. However with this new cam the engine will make much more power above 3000 rpm. Keep in mind when the torque curve of the engine is raised you will need more stall speed in the converter to allow the vehicle to accelerate at low rpm (below 3000). A good rule of thumb for advertised cam durations up to 248 degrees, a 2000 or 2400 stall converter is a good choice. Advertised cam durations up to 268 degrees, a 2400 or 3000 stall converter is a good choice. Advertised cam durations over 272 degrees, a 3000 to 3600 stall converter is a must. That's why you had to turn the idle up to keep it from dying.

My dad said he could take a look at her, but you are in Florida.
What part of Florida?

Read this I took from Summit Racing------>

What a Converter Does

Simply put, a torque converter is a hydraulic coupler between the engine and the transmission. It changes mechanical torque (engine torque) into hydraulic pressure before sending it back to the transmission. The converter also multiplies the torque at low speed or during periods of high engine load.

The insides of a converter consist of an impeller, a stator, and a turbine, all surrounded by transmission fluid. The impeller rotates at engine crank speed, acting as a fluid pump. The turbine is the output device hooked to the transmission input shaft. The stator sits between the two, acting as a torque multiplier when impeller speed exceeds turbine speed. When the converter reaches its stall, or lockup speed, the stator stops multiplying torque and the converter essentially acts as a fluid coupling. When the vehicle is coasting (no load), the converter directs torque back towards the engine, acting as a brake.

What is Stall Speed, Anyway?
The most misunderstood aspect of torque converters is stall speed. Many people think if a converter is rated at 2,500 rpm, their car will rev up to that rpm and then take off. That's not how it works. Stall speed is a function of engine rpm. The more torque an engine makes, the higher the rpm the converter will stall, or lock up at, and transfer that torque to the transmission.

There are two types of stall speed-foot brake stall and flash stall. Foot brake stall (or true stall) is the maximum engine rpm achieved from a complete stop with the transmission in gear, the brakes apllie,d and the engine at full throttle. The rpm reached just before the vehicle begins to move forward is the true stall speed of the converter.

The problem with foot brake stall is that you will end up overpowering the brakes and suspension before you reach the converter's stall speed. The only way to really measure true stall is by using a trans-brake. This will keep the vehicle from moving, allowing the converter to absorb 100 percent of the engine's torque. Race classes that do not allow trans-brakes are often called foot-brake classes. In this type of racing, the rpm obtained when the brakes are applied and the vehicle is not moving is considered to be foot brake stall. When the brakes are released, the engine goes to full throttle and “flashes" the converter.

This brings us to flash stall. It is the maximum engine rpm reached when you do a full-throttle launch with the transmission in low gear and no brakes applied. Flash stall is always lower than foot (true) stall because there is less load on the converter. Changing the load on the converter can change the flash stall rating. Additional engine torque, a higher(numerically lower) rear axle gear, or adding vehicle weight will increase flash stall. Less torque, a lower (numerically higher) gear, and less weight will decrease flash stall.

Another factor that gets confusing is converter slip. Slip is basically a measure of converter efficiency. Due to the difference in rotating speeds between the impeller and the turbine, there is usually a five to 10 percent efficiency loss at cruising speeds for non-lockup converters. Because a converter gradually slips, or creeps up, to full stall/lockup rpm, the higher the stall speed, the more slippage you get. On a street-driven vehicle, that can lead to poor idle and low end performance, worse gas mileage, and most importantly, greater heat buildup-the number one killer of converters and transmissions. If you do run a high stall converter, a good transmission cooler is a must.

What Kind of Engine Are You Building?
Before you even crack open a torque converter catalog, you need to think about the type of engine you have or are building. For the street, you need to match low and midrange engine torque to the converter's stall speed. For example, if you are building a street small block that makes most of its torque around 2,500 to 3,000 rpm, don't get a converter that stalls at 4,000. Not only will the car be hard to drive, the converter will constantly slip and will eventually be destroyed due to overheating. If you build a big block that makes its torque at 4,500 rpm, don't expect it to be much fun on the street because of the high stall converter and big rear axle gear required to lock up the converter.

Camshaft selection is also critical to torque converter selection. On the street, many people will choose a cam that will put an engine's rpm range 1,500 to 2,000 rpm higher than stock. Not only does that reduce bottom end torque, a higher stall converter will be required to match the new torque peak. Many people will get the recommended converter, but neglect to upgrade the rear axle gear to compliment the higher stall speed (more on gear ratios and tire sizes in a minute).

Say you built a small block V8 with a 235 degree (at .050)/.488 inch lift cam and added a converter rated at 3,000 to 3,500 rpm. To make the combination work properly with a minimum of converter slippage, you will need a 4.10 or higher rear axle gear with 26 to 27 inch tall tires. Illustration One shows you approximate stall speeds based on engine type, cam duration, and rear axle gear ratio.

Nitrous oxide and superchargers also affect converter selection. An engine with a power adder produces more torque than it would if it was normally aspirated. That means a nitrous or blown engine needs a converter with a lower stall speed range. Otherwise, the converter will stall too high, causing it to slip and eventually self-destruct due to the extra heat.

The Final Ratio
Rear axle gear ratio and tire diameter are very important to proper converter selection. You need to have a final cruise rpm (rpm generated based on tire diameter and rear axle gear ratio) that allows the converter to function at full lockup at cruising speeds. If you don't, the converter will constantly slip.

Size Does Matter
Torque converter size can also be confusing. Converters can range from 11 and 12 inches in diameter all the way down to 7 inches. Basically, the smaller the converter, the less fluid has to be pumped through it. Less fluid means less drag on the converter internals, which allows it to stall at higher speeds. That's why you see 8, 9, and 10 inch converters listed for racing applications. In general, you want to avoid small converters on a typical street car due to the much higher stall speeds (usually 3,000 rpm and up).

If you are adding a lot of nitrous (over 200 horsepower), running high blower pressure (over 12 psi), or use a trans-brake, you will need a converter built to handle the extra stress. The extra torque generated can cause a converter to “balloon", or expand in diameter. Look for a converter with a high quality stator assembly and an anti-ballooning plate to keep it from expanding.

The Fitting Room
A common complaint about aftermarket torque converters is fitment. Often, a new converter will not fit the transmission's input shaft because it is built to closer tolerances than OEM converters, so the hub-to-input shaft fit is tighter. Just because the new converter will not slip onto the input shaft doesn't mean the converter is defective-just use a little extra effort.

A good way to check if a new converter will fit properly is to compare it to the stock converter you are taking out. Illustration Three shows the three critical dimensions: overall length (from engine mounting face to end of hub), hub slot depth, and hub slot inside diameter. Before you remove the old converter, check the dimension from the bellhousing to the front. This will help you position the new converter properly.

Other Considerations
A higher stall converter will place extra stress where it mates to the engine, so make sure you use quality converter bolts and an SFI approved flexplate. Flexplates for Chevys are usually double drilled for small and large bolt patterns, eliminating the need to guess which bolt pattern you have.

Aftermarket torque converters are neutral balanced, designed for internally balanced engines. Most externally balanced engines have the balance weight on the flexplate, so this is no big deal. But on externally balanced Chryslers-340 and 360 small block and 440 big block-the factory put the balance weight on the torque converter. If you have one of these engines, make sure to get the appropriate flexplate counterweighted to match the engine balance. Most SFI approved Chrysler flexplates have this counterweight.

Don't consider this to be the end-all and be-all on torque converters. The best way to get the perfect converter for your application is to talk with the tech guys at Summit or directly with the companies that build the converters. Hopefully, this guide will help you ask the right questions-and understand the answers.

http://www.summitracing.com/streetan...BD43F224310%7D