Stall convertor for 700r4

[crazy canuck Z8]

My 73 240 with a full roller 350 with nos is almost on the road,i have been reading all the info i could find on this site and would like to thank you all! I am not very good on the computer so it may take me some time to get pictures for you all to see,but it is going to be nice.My question is,how big of a stall can i run with the r 200 rear end with 3.9 gears,i am running a 600 lift solid roller so i need a fair bit of stall speed of the line.What kind and size of stall is anybody else running?Thanks again newby.

[Brad-ManQ45]

You may want to give some duration specs for the cam too....as well as other engine specs - induction for instance.

[Paz8]

Assuming that your car is going to be street driven, and not a drag car, I'd say try a 2400 RPM stall with lock up clutch. Higher stall convertors generate more heat in the trans so you will need convertor lock up if you want the trans to last longer.

Just my opinion, I'm sure there are others.

[dr_hunt]

Ultimately, you'll have to take into consideration the rear gear, tires and your nos. With a 4K stall I can drive on the street fine, the z is soo light that it just scoots along even with a powerglide. I can take off in high gear and leave rubber for 30 feet from the slicks on the street with a .645 lift roller and 270 duration at .050. Roller cams seem to be inherently different in terms of low end compared to solid's or hydraulics, although I would consider a 3K the minimum for hot street or mild race type motors on the street. A .600 lift solid roller isn't that big, what is the duration at .050? Also the NOS will have a big impact on the stall of the converter.

 

Edit: Also whether or not the 700 is built right will dictate how long it lasts. In stock form they are kind of weak and it sounds like your going to be making alot of power.

[getZ]

I'm running much less of cam, 230@.05 and 480 lift, with 3.9 gears, 26 inch tire, 200r4, but am very happy with a 2400 stall. I figure as light as the z car is I could step down stall speed to 2000 and still be happy.

 

My guess is a 3000 stall would work for you.

[Guest zfan]

I am running a 236/242 duration roller cam with 570 lift. I also have a well built 700r4 transmission with a 3500 rpm 9.5" racing converter. It takes awhile to get used to it but when you do it's a piece of cake.

 

A 3500 rpm converter will hammer you back on a dead launch compared to a low stall converter. Depends on what you want.

 

Mike

[crazy canuck Z8]

I have been at work,sorry,thanks for the help.My cam specs are 600 lift and 274@.050 i am worried about the rear end being able to handle the3000 rpm launch?The car will have a little street driving and some friday nights at the track with my sons 16 and 15.

[getZ]

I'm not sure if you are thinking that a 3000 stall suddenly grabs at 3000 rpm, like dumping the clutch. If you are, it doesn't quite work that way. It's more like it slips really bad until you get to 3000 rpm, kind of like a transmission that is slipping all the time. Automatics are usually kinder to drivetrain parts.

 

Seems like the first thing to go is half shaft u-joints unless you upgrade to CV joints. Some of the really fast guys even break those.

[dr_hunt]

If you use a trans brake it is a brutal launch, but I find that foot braking with the engine at idle and stabbing it produces a 4500 flash on my 4000 stall and the trans brake will stall it 4300 at WOT. Flashing the converter from an idle produces bigger wheelies and feels alot smoother, but the t brake feels more brutal and probably is, especially on parts.

 

Remember that advertised stall doesn't mean much and they are pretty easy on parts IMO. A 3000 stall with your motor may stall 3200 or may stall less cause the z is so light and starts to move right away. All of these things factor in the stall equation. I think that everyone can chime in but a 3000 is about right for street and a 3500 is probably ok for a z cause they are so light.

[Guest zfan]

If you use a trans brake it is a brutal launch' date=' but I find that foot braking with the engine at idle and stabbing it produces a 4500 flash on my 4000 stall and the trans brake will stall it 4300 at WOT. Flashing the converter from an idle produces bigger wheelies and feels alot smoother, but the t brake feels more brutal and probably is, especially on parts.

 

Remember that advertised stall doesn't mean much and they are pretty easy on parts IMO. A 3000 stall with your motor may stall 3200 or may stall less cause the z is so light and starts to move right away. All of these things factor in the stall equation. I think that everyone can chime in but a 3000 is about right for street and a 3500 is probably ok for a z cause they are so light.[/quote']

 

 

He is right on the money! If I had a heavier car I would go less stall, no doubt. Sometimes wish I had gone with a 3k too.

 

Mike

[Guest 73TPIZ]

.......................... Flashing the converter from an idle produces bigger wheelies .................................

 

Holeeee maackarrel. Wish i coulda seen you at SEZS6. Maybe next time.

 

My TPI is more torque than HP so i will try a 2500 that i bought when i get the 355 in. Hoping for a ~2000 footbrake stall with my light weight and low HP setup. Currently the 305 w/ 2-5k cam and stock stall leaves at 1200rpm which sucks. It was ok when i had the 3.70 gear in but with the 3.23 gear she bogs real bad 'til ~1800 (if the street tires hook). But its 2-3 tenths better overall so glad i went w/ the taller gear. Would love to cut a 1.5-1.6 60ft on some good tires. 1.9-2.1 60ft sucks.

 

Later,

[dr_hunt]

Thanks! Next SEZ, I'm thinking of bringing the twin turbo Monte SS. If I get a longer trailer, might bring both cars.

 

Believe it or not the B&M holeshot at 2500 stall works pretty good for mild street motors. The first v8 z I ever rode in had a 350, 2.02 heads, xxxxx151 350hp/350 cam from GM, dual plane intake, scarab kit, th350, B&M holeshot converter and would squat and haul ***, beat everything around here except exotic roller cammed race cars. It was wicked!

[crazy canuck Z8]

Thanks,going shopping this week,will have to chose between 2500 and 3000,but if 3000 is not any harder on my drivetrain i think thats the route to go.Tires are 225 50r 15 on centerlines saharas,what kind of times did you run in your first v8 z?

[Guest zfan]

FYI,

 

I do not stall my car up more than 1500 rpm's and I am running a 3500 stall converter. When I launch and hammer it, it just launches hard with little or no squat since I went to stiff coilovers. You don't necessarily have to brake stall it up to 2k or more.

 

Sometimes when I stall it too high the tires just blow away on the launch, thus slower 60 ft.'s. But every car is different. On drag radials, small ones at 235/60-15 Mickey Thompson's I have cut a best of 1.49 for 60 ft. 1.50's is more the norm.

 

Mike