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Discussion Starter · #1 · (Edited)
Ok. So I posted a few days ago in reference to choosing stall speed for my 383. I’m making a new post because that one kind of went a different direction because I screwed up on my vehicle weight. So here it is.
385 sbc forged internals
Comp hyd roller camshaft (I’ll post the card in a picture)
Cam power band is 2000-6000
11.1 compression
Vehicle weighs 3,500 lbs
4.11 gears in the 9” with 28 inch tires 275/60r15.
Th350 transmission.
I also have a chunk with 3.50 gears in it. I never drive on the interstate. Right now it has a tci street fighter stall in it. It’s rated for 3000-3500 but I’ve seen people say it’s more than that because tci converters are loose and junk. Makes a lot of sense too. I have to give it a good deal of throttle to get the thing to move. Seems like it doesn’t launch really good. It’s a stout small block.
I’m looking at a stall that’s rated for 2800-3200. Anybody got a similar combo? It’s a streetcar btw. Should I go lower on the stall? Maybe like a 2200-2800?
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If you really want it to jump when you stand on it I wouldn't go lower than the current 3000-3500 stall speed....but get the converter from a good company, not that TCI junk.
No B&M or ACC/Alabama Boss Hogg either. Junk.

Lower stall speed is just going to give away performance if you buy from a good company.

FTI, PTC, TSI, or even Freakshow Performance or Jeg's XHD if you are on a budget. Hughes or Coan are also good.

When built tight and right, you can get your 3500 stall rpm for great launches and it will still behave well at lower throttle and cruise and not feel like it is just slipping away.
 

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can i piggyback on this as i am currently looking for the converter size advice for my truck occasional street driver and some highway back and forth to work

421 sbc / turbo 350 tranny
CAM is hyd roller comp 237/246 on 113 LSA
Tires are 275/55 x 22
going in a 72 C10 average curb weight is 3600 LBS
engine builder says 3500 to 4500 stall speed. for the street?? seems a little high to me
????

if i am cruising on the highway with 3.73 rear end around 2700 RPM;s will the converter be slipping??
 

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Actual stall speed only happens under full throttle, at cruise speed you aren't putting enough power into the converter to force it to slip, so at your 2700 rpm cruise it really isn't slipping a 3500 converter (if the converter is a quality piece!).
It is a load sensitive device.
All that "slips at cruise"mantra is just shade tree magazine reader crap, true only with a cheap converter or 40 year old converter technology.

in your case your engine builder would be correct if this was a street/strip ride you expect to be hairy and scary and you'll live with whatever manners you get from it, or a sometimes mud toy.....but not so much correct considering your street cruiser/driver requirements.

the FTI you are looking at would be a cood fit, they build quality stuff.

Because of your cubic inch, any converter speed spec you look at will tend to end up at the higher end of it's listed stall range in your package of big cubes, heavy weight, and large tire diameter(almost 33").

As a general rule, smaller diameter converter means higher stall speed, along with the ability to build it tighter clearance-wise internally so it behaves better at part throttle, compared a larger diameter converter with loose clearances to get the higher stall speed which makes them feel sloppy(because they are!)
 
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