Item Posts    Sort Order

torque converter

 
83chevy91
I love my Chevy Chevette!
Posts: 8
Joined: 08/13
Posted: 09/29/13 08:23 PM

I have a 83 chevy c-10 pick with a mild built 350 engine. The motor has a .280 duration .480 lift cam. With a th350 tranny and a 4.10 rear end gear. What rpm stall converter do I need for this application?  

Post Reply
Dave632
I mow my lawn and find Chevys
Posts: 2253
Joined: 07/08
Posted: 09/30/13 05:28 AM

If you are using this on the street go with a very mild converter, 22-2800 stall.
You will have to put some kind of higher stall in it so you can idle at a stop light.
High stall converters produce more heat which is a tranny killer. Put a trans cooler in too.  
[[SUPPORT AMERICAN CARS, STOMP A RICE CAR TODAY.]]

Post Reply
pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 09/30/13 12:00 PM

Is that .280 duration the advertised duration or the actual duration. As Dave632 mentioned you should have a very loose torque convertor, at least what he suggested.
If your using the TH350 trans a 2800 to 3200 stall speed will be a good choice.
  The 4:10 rear gear is great if you have a rear tire that's 28"to 30" tall. The taller your rear tire you will lose rear gear.
  Its really a nice combination for a street sleeper.
1.What size header are you using?
2.Carburator size
3.Intake manifold.
4.For the street I would use a Vacuum Secondary carb.
5.You didn't mention what heads you have.
6.Remember running a performance torque convertor makes a lot of heat. You will need a separate trans cooler. (Run it separate from the engine radiator).

Good Luck, and let us know how your project is coming along.

Bob

"NO RICE BURNERS ALLOWED"

Let us know how you make out. Grin  Cool  

Post Reply
83chevy91
I love my Chevy Chevette!
Posts: 8
Joined: 08/13
Posted: 09/30/13 08:36 PM

Well I already got the truck on the road I've got aluminium head 2.02 1.60 valves 670 street avenger holley edelbrock rpm performer intake and 29 in tires. The truck feels great plenty of power. I've got a Hughes stall converter that flashes at 2500. The truck feels great plenty of power. I'm really happy with it. When I take off its really strong but when I hit about 3000 to 3200 rpm it really comes to life. Friend of mine suggested a 10 in converter that flashes at 3500. He says it will come to life as soon as I nail it. It doesn't hesitate it just seems to open up a little more. I also mentioned in some other post that I have broke two bell housings and have yet to figure out why. I think I'm gonna try the super bell housing. But I also wanted some other suggestions on the converter while I had the tranny out.  

Post Reply
pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 09/30/13 11:22 PM

Sounds like your combination is working. You fine tune it and it will really snap your neck. So many times guys will put a bigger cam in their engine and are very disappointed. Because the engine doesn't make good power. When all they did was move the power/torque curves up to a higher RPM. Tell them to install a lower rear gear ratio, and it changes everything. Grin  Cool  
  Like you stated at 3,000RPM it really wakes up. If it pulls hard to your maximum RPM for the cam.
 

  Try these, and see if it helps or not.
1.Because you have an automatic you can go one step colder with your spark plugs. (For an example if your using an AC 44 TS try an AC 43 TS The R stands for a resistor plug, and you don't need a resistor plug. Then set the gap to .025 to .028. Then make a couple hard runs bring the engine to its max RPM. Then shut the engine off, and pull #1 and #6 spark plugs. (They fire together). See if the plugs are close in color. (I like seeing plugs from both banks). Look at the Porcelain. If you don't have any color make a couple more WOT passes, and read the plugs again. If your using Racing Gas the plugs should color after a couple passes.

2.Set your base timing at 12 degrees (if you are using a vacuum advance distributor disconnect the vacuum source). and your total advance to 32 degrees and keep pushing it up until you feel the engine lay down or ping. Small Block Chevy engines love timing, and have it all in at 2,500 to 2,800 RPM. But keep an eye on your spark plug color.

3.Breaking bell housings can be a misalignment of the bell housing case to the center of the crank shaft. (I WOULD HAVE THE DRIVESHAFT CHECKED FOR BALANCE, AND TO MAKE SURE IT IS RUNNING TRUE). If you have a bent driveshaft you will keep breaking the bell housings. That's easy enough to check. Jack the rear up, and put jack stands under the rear housing. You can get close enough using a China pencil or chalk, and touch the driveshaft in as many areas as you can. Just let the engine idle while your doing this.
  If the driveshaft is bent you will get a hit/miss spot on the driveshaft. If the driveshaft went through 2 broken bell housings it could have hurt the driveshaft even if its a good aftermarket shaft.
  How about the engine? Was the engine balanced? It can be a myriad of things to cause a broken bell housing. I've seen them explode and tear the floor out of a car. You have to start somewhere, and you will need to see if the Driveshaft is bent or out of balance anyway.  

4.Pinion Angle could be another reason you broke the bell housings. When you have a loose convertor the torque multiplication is enough to break the Bell Housings. I can try and explain how to set pinion angle, but what rear are you using?

5.Chris Alston has a book its from back in the day, but it still applies. The book is called Door Slammers. It shows how to get the correct pinion angle, how to set-up 4 Link, Ladder bars, slapper bars, and any type set-up you maybe using. He even goes into detail about installing Roll Bars. But anyway you have an alignment problem somewhere in the rear suspension. As you accelerate watch what the Rear Yoke does? It wants to be driven upward, and that's when your pinion angle has to be correct. (Just Power Break the engine). For a drag racing car you want 6 degrees when your accelerating. Then as your into your run the car will settle down and the pinion angle will change again. Rear Driven Street cars do the same thing.

6.Are you using a solid motor mount, and a rubber or stock type trans mount. That can cause a vibration that will break the Bell Housing.

7.I wouldn't make any dry hops or flash the convertor up your stall speed until you find out what's making the Bells Break!!!!

8.Is your engine set back? As I mentioned you want the car level, and then see at what angle your engine is. It should be ZERO Degrees Once you have that go to the driveshaft, then the rear yoke. Its really not complicated once you get your car level to the floor.

9.Now the other thing do you have a trans break? If you do and your bring the RPM up over stall your shocking the suspension really hard, but that's what makes the car hook and go straight.

10.If you can just have someone with a movie camera, film the rear suspension. Then you will see what I'm talking about. How the rear pinion yoke wants to lift the car up. Your package is really nice and it works. Now you have to find the reason for the Bell Housings breaking. Maybe some of are GURU friends will have some other thoughts...

If you have any questions PM me. Grin  Cool

Bob

"NO RICE BURNERS ALLOWED"  

Post Reply
83chevy91
I love my Chevy Chevette!
Posts: 8
Joined: 08/13
Posted: 10/01/13 09:26 AM

So will the plug trick compensate for getting a higher rpm converter? My tining is at 12 and 32 now so will the plugs make the power come in all together? I don't really want to have to buy another converter since nothing wrong with mine. I'll definitely have to check all the things you mentioned for the bell housing  breaking. Thanks for all the tips I really appreciate it. Now I just have to do some checking.  

Post Reply
pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 10/01/13 06:16 PM

I found some information and Chris Astons book dated 1985...Here's what it says about pinion angles. (I quote).
  The rear axle centerline must be parallel to the top of the frame rails in a passenger compartment. If this is not the case, then one rear tire will have more weight on it than another. This will cause the car to drive in the direction of the weighted tire. This is called (PRELOAD). All chassis' should be set-up with no pre-load. Preload should only be added if necessary to make the car go straight.
  To check the rear for (Parallel) is quite simple. Coil over and leaf spring suspensions have slightly different procedures.
  For a car to drive straight forward. It is essential that the axle centerline be exactly 90 degrees to the chassis centerline.(Similar to what I was saying about the bell housing being centered to the center of the crankshaft...
  To check this its relatively easy. Drop a plump bob from each rear axle flange exactly in its center. Put a cross on the floor directly under its centerline. Put a cross on the floor directly under its center. Put a cross on the floor directly under the string centerline, about five feet ahead of the rear axle housing. Measure on a diagonal from each bob to the cross. Adjust the rear axle housing so that the difference on the right and left sides is less then 1/4".
  Its very important to make sure your chassis is square and holds that 1/4" centerline from the front to the back. If you are the original owner was the truck ever hit hard in any corner. You with a helper measure every corner to corner chassis hole to chassis hole. Mach up a schematic of the car and keep those for references. Tell me what type suspension your using, and I'll see what you need to do next. Somewhere there is a dimention that's out of wack. Think of it this way. If you ever made the Pine Wood Derby kits for cubs scouts. If you where to move the front wheels a 1/16'th and then push the car. You will see it does not roll straight. If you correct that the car rolls very nice.      

The plug trick is to keep the cylinder and the top of the piston cooler. In turn it will make more power. You can even experiment and try going two steps colder in heat range. The AC, and Autolite plugs run their heat ranges as follows. For example AC R 45 TS is a hot plug. An AC R 43 TS is a colder plug.
Now if you use an NGK plug the heat range runs the opposite way. For example. a #4 plug is hotter then a #2 heat range plug. Just some FYI: you don't want to go too, too cold a plug, you can wind up fouling the plugs.... That's why we are here so ask questions. "THERE ARE NO STUPID QUESTIONS,ONLY STUPID ANSWERS"


Bob

"NO RICE BURNERS ALLOWED"  

Post Reply
pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 10/01/13 06:26 PM

Just some FYI. I back-halfed my first my first Race Car. With only a Plump bobs, T-squares, and tape measures. I measured and measured , and measured everything before I Tig welded it together. That car with a 6,500 torque convertor hit hard (like a got punched in the chest). I put ten runs on it before I really put my foot in the carburetor. It also hooked very hard. I actually was in a 10 second bracket. I went 9:94 with it. It scraped the rear bumper, I then installed wheelie bars. It was a fun car to drive. Grin  Cool  Shocked

Bob

"NO RICE BURNERS ALLOWED"  

Post Reply
TO TOP