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Discussion Starter · #1 ·
Im having alot of trouble with such things as stall rpm and gears. My poor 231cu 3.8l buick v6 motor just doesent make alot of power, not to mention it has to pull my 82 chevy truck around, now with a TH400 trans. Im hoping this doesent turn out to be as big of a negative deal as everyone is saying. What are the best things i can do to help the motor? Im confused if a higher or lower stall rpm would be good, gears? Any upgrades i can do to the trans to ease the drag?
I should mention the th400 is out of the truck still, never installed. Waiting on torque converter choice. My TH-200 finally bit the bullet.
 

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boatbob2
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Buick 231..........

Hi,i have a warmed over Buick 231 in my 83 Toyota pickup,its dependable,but not a fast motor,AND my truck is a LOT lighter than yours.i think a 350 SB is the way to go. (i have that engine in my 83 C-10,with a 700R4.)
 

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Discussion Starter · #5 ·
looking into going 3.73 but its whatever came from the factory in there now im sure. Its a 1982 chevy c10 silverado. im not looking for advice on what engine or trans too choose. I already have a buick 231 3.8l v6 in the truck, and im about to put a TH400 behind it. Just wondering what gear/stall ratio is going to be best to help the motor out. Or if maybe there is an upgrade for the 400 that makes it less draggy. I guess im asking if anyone knows where to find factory torque curves for this motor..
 

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WFO
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0trbo4myCHEVUICK said:
looking into going 3.73 but its whatever came from the factory in there now im sure. Its a 1982 chevy c10 silverado. im not looking for advice on what engine or trans too choose. I already have a buick 231 3.8l v6 in the truck, and im about to put a TH400 behind it. Just wondering what gear/stall ratio is going to be best to help the motor out. Or if maybe there is an upgrade for the 400 that makes it less draggy. I guess im asking if anyone knows where to find factory torque curves for this motor..
Use a stock TC if the engine is stock. 1800-2000 rpm is plenty. A lower rear gear will help but it will also run up the cruise rpm on the highway so be prepared for that or use a gear in the 3.4-3.5:1 range and split the difference. A lot depends on how you use this truck- as a DD or as a work truck, etc.

But until you know what gear is in it now, this is guesswork. You can check the RPO code sticker (often in the glove box) and see what the ratio was originally in it- it's likely the same as when it was new.

More on checking the gear ratio here.
 

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Only thing I can add is I hope you weren't looking for economy in this deal.
you'll need a 3.42, 3.55 3.73 and an 1800-2000rpm converter to help that little 6er get it done.

Nothing wrong with a V6 fullsize PU; we had a mid 90s chevy 1500 with a V6, 700r4 and 4wd with 'helper springs' in the back. Plowed huge piles of snow, towed horse trailers, loaded tons of hay and grain in the back.
It did better on gas than our old 70s era power wagon (360, 727 and I think 4.56s) but not by much really. The deeper 1st gear of the 700 would make life easier, not to mention the OD (don't tow heavy in OD though); but, use what you've got...just be realistic
 

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Discussion Starter · #9 ·
Yeah, i know this isent ideal for any reason at all. hopefully ill be throwing in a 350 but well see how money works out. Surely ill get alittle better gas milage not having to floor it everywhere i go at 30 mph. Also was hoping someone could give me some insight on this transmission.. the ID tag reads. 82 FM 32940
 

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Discussion Starter · #11 ·
thanks! Does anyone know if there is a truck with the driveshaft I need? Shouldnt I beable to find a truck with a th400, yank the shaft and yoke, shift linkage and roll? As long as the truck is single cab and regular sized bed like mine?
 

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My 85 C10 has 3.73 rear , 305/ th350 c , performer cam/intake ,vortec 906 heads shaved, 100 headers, stock qjet, and a dynamic 3000 stall. Vortec heads and the stall add so much to the performance. The launch is very strong and governor recalibrated for 5200 shifts. This makes for a dependable fun utility vehicle.

A higher stall can really get you going for the hole and not sacrifice a thing.
 

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Discussion Starter · #14 ·
yes i bought a chevy to BOP bolt pattern adapter. its 1/8" thick.. i still havent figured out what im going to do about a driveshaft... got new trans cooler with fan from jegs yesterday with the adapter plate, dipstick and new champion 2 core radi. Couldn't stand to let my new trans drink fluid from the stock cooler. I should be getting the summit 17 - 2000 converter tomorrow as well! Does the fluid that you put in the converter stay in the converter? what about 50/50 lucas n fluid in the converter? Or does it all just mix? I already mix two bottles with my fluid changes.. :thumbup:
 

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Discussion Starter · #17 ·
thx cobalt.. went with your advice and got the stock tc.. sure it'l work out! Am i gonna have to get a custom driveshaft? Is there any way to make up for the 1/8" adapter plate? grind the yoke down?
 

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WFO
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0trbo4myCHEVUICK said:
thx cobalt.. went with your advice and got the stock tc.. sure it'l work out! Am i gonna have to get a custom driveshaft? Is there any way to make up for the 1/8" adapter plate? grind the yoke down?
There is enough engagement between the output shaft and yoke to compensate for the thickness of the adapter plate so you don't need to do anything to the driveshaft. I would be sure the U-joints are good since you have it out anyway.

Be sure to use the washer/spacers between the flexplate and torque converter to space it properly to compensate for the adapter thickness. That should be covered in the instructions.
 
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