I am really thinking of doing a 2500 stall converter on my T/A, and was wondering if it would have any affect on me when normally driving. For example will it help me to rev better out of say 2000 rpm when in 3rd gear, or is it just gonna help me off the line. My only worry is I will have a very narrow power band as my stock shiftpoints are 4500 to 2nd and 4100 to 3rd, and I worry about only having 2000 usable rpm. How is a high stall converter for a daily driver?

 

It will be "looser" at all speeds.

If you have that low of a powerline, you don't need a higher stall converter. Save that for the day when you have a healthier cam. Then, it will be fine for daily driving.

 

I do defnietley need to do something about the low end, between the single plane manifold and the cam, the low end needs improvement. I need to change the stock shift points, but I do rev it to 5500 when shifting by hand. So you wouldnt recommend a torque converter? It wouldnt do any harm, I do need some definite low end improvement, and my motors main torque is from 3500 rpm and up.

 

If you are going to use a modified 12" torque converter, then it will not help much (if at all) from a 30 mph roll. If you have a 9.5" A.C.T., or the Vigilante, then it will help pretty much at any speed, as long as the stall is not to high. Before I recommend a specific stall, I need to know the rear end ratio?, the duration of the cam at .050 lift?, what kind of manifold and size of carb or injection?, the kind of driving you do?, etc. Let me know?

 

Okay, I have 3.23 posi. I have an XE262 cam with duration of 218/224 @.050 and lift of .462" and .469". Single plane holley street dominator with divided plenum with stock quadrajet. My driving, uh, lets just say its semi enthusiastic. I like to step on it when challenged, but I do drive the car on an almost daily basis because I love driving it so much. Planning on Vortec heads and a new manifold, perhpas a performer RPM. May move to a better carb after im through emmisions, but will probably tweak the stock one. I currently have 487 heads from a 71 350, and compression of about 8.5:1 (1971 350/270 horse). Thanks for the help I really appreciate it.

 

Put a 4.10 gear in it, add a 2500 plus stall and you will notice a difference. That is if you like to smoke the tires. The higher the stall the steeper the gear you want to run on the street. Lets say you ran a 3K stall with a 3.08 gear, the converter would be constantly slipping and creating more heat in the trans during daily street driving. Make sense???

 

4.10's with a 700r4 for a daily driver is overkill.


3.42's or even 3.73's would be a nice uprgrade too

 

Add the 9.5" TC and a performer manifold, not the rpm performer. Try this before any rear end gear change, you might not need it.

 

What kind of dist. do you have? Are you running enough advance? Compression is a little low for the cam, but should run well. I would go with a gear change BEFORE a stall on your combo. Stick a 373 or a 410 gear in it, and get the carb and advance right. AND IT WILL RUN. 64cc ported heads would also help alot. I think your street dominator is better than a rpm. Make sure that the secondarys aren't opening too fast on your quadrajet, that'll kill it too.

 

For a daily driver you should put in 3.23 or 3.42 gears with a 700r4. With 3.73 and up even with od you'll be running a consistent 3000 rpm or higher just to hold 60 mph on the highway which in my opinion is just too much of a gas guzzler operation. Rember for each 1 pt = 1000 rpm more you have to run your car at to maintain the same speed = greater acceleration = less top speed. I personally went from 2.73 up to 3.23 gears and can say that it moves a whole lot faster without killing my daily drive that much. With prices being higher than ever, I can't afford a daily driver than needs a fill up more than once a week. Adding a higher stall TCC will improve mileage & 1/4 mile times. Adding in a higher gear set will improve 1/4 mile times and drop mileage. So choose an in between 2500 stall with a higher gear set. Hopefully the stall offsets the loss in mileage. (even TBI's can use that kind of boost since 2400 is their standard torque peak)

 

Slade1, have you ever ran a 373 or 410 gear on the street? Or are you guessing? My car turns 2500 rpm at 70 with 245/50/16 tires. About 200 rpm more than my 373s did. Depending on what cam a fellow is running, that could be about right. When you start modifing these cars, is gas milage realy that important? If we want gas milage we'd be leaving them alone, wouldn't we?

 

With 3.73's & 26" tall tires at 3,000 rpm is about 89 mph. Do the stall first as I said, you might not need gears, unless you are looking for every bit of et as you can get, then the gears might help out a little.

 

Slade1, you must be calculating in 3rd, not OD. My car is 2200 @ 60mph with a 3.70 gear.

 

I'm currently running the stock distributor (HEI) and plan on upgrading after I get a trans pak shift kit, as i feel Im wasting a good deal of time in the shifting of the car. Timing is currently set at 16 degrees advance, which was what they ran on the 305 buildup in car craft with that cam. That advance about right?

I'm shooting to break into the 13's with this car and shut my buddy up about his 6 speed LT1. Vortec's are on my list for next spring break after I have the cash. Nice 10:1 compression and some nice ported heads out to help the motor along over my stock 76cc heads from 1971.

 

I think that may be a little much on the timing. Try setting it at 8*/10* and get a recurve kit for the dist. Crane makes a very good kit, with an adjustable vacume diaphram. Set it up for a total of 34/36* in by 3600 rpm. Use your stock GM weights in the dist, and use the springs from the kit. With the adjustable kit you can make timing changes, at the track easily. You may also have to use the limiter, to keep from having too much total. I had to on my 77 T/A. If your Quadrajet secondarys are opening to fast, It'll be lazy too. Tighten up the secondary spring a little and see what that does for you, should have a little better responce.