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Alright guys I have to plead ignorance on this. I sort of understand what a shift kit is, but could someone explain it to me. When doing some research for my new 350 engine that I'm getting ready to install, I would read notes like "requires shift kit" or "3000 stall", etc. What the heck does all that mean? I'm wondering if I will need to modify my TH350 tranny when I put in the new engine. Thanks for any help so I can understand this better. Regards, Don

i know a little about what they are talking about enough to be dangerous. the shift kit reconfigures the shift ponts for a crisper shift and less lose of rpms. the stall is the higher rpms you can reach without bogging the trans down. to hook up you don't have to do anything unless you want to hotrod it. that is basically what they are talking about, customizing the trans for your personal use pattern. ron

if it says it requires a higher stall, it is because the powerband of the motor has been shifted to a higher rpm band ususally due to the camshaft. so if you use a factory stall converter, it will be a slug off of the line until it gets wound up into the rpm's where it starts making power. you won't be able to lanuch very hard off the line if you try to race it.

if you have too big of a stall converter on a street driven car it will not have very good street manners. but that would be like a 3,500 rpm converter or higher.

Thanks guys for the help. Since my new engine is only mildly modified it sounds like I will be okay with the stock TH350. Regards, Don

what are the specs of the cam in it?

The term "shift kit" is a registered trademark of TCI. But most kits designed to "hop up" an automatic transmission end up raising the line pressure so that it shifts up more firmly. The degree of firmness (or the less clutch slippage internally) depends on the type of kit, the degree of modification and the amount of throttle applied (in a TH350.)

When a kit is installed and the clutch slippage is decreased, the amount of heat build-up in the transmission can actually be decreased. Many people who install them claim that they help extend the life of a transmission by minimizing slippage, wear on the clutch surfaces and keeping the tranny cooler than it would normally run.

I like the way my El Camino [censored] with a B&M TransPak (Stage II) installed. There are 3 ways to install it and I took the middle option. It's the "street/strip" level of modification. Stage III is race only. It will chirp the tires on the 1-2 shift at anything over 1/2 throttle. Again, I like it that way.

If you want firm, crisp shifts, then a kit is the way to go. If you like smooth, gentle transitions from one gear to the next (even at full throttle) then the stock setup is probably the best choice.

As far as "stall", they're referring to stall speed of the torque converter. That's the maximum speed the TC will allow the engine to rev to without turning the transmission input shaft. (That's the nutshell version.) If you powerbrake an automatic transmissioned car or truck, the stall speed is where the tach stops climbing and stays steady...without beginning to turn the rear wheels.

Most stock converters are in the 1200-1800 rpm range. But many hopped up motors don't develop much power at that speed. So a looser converter allows the motor to spool up to a higher rpm before it stalls. If you have a motor that "gets on the cam" at around 3000 rpm, then a 3000 or 3200 rpm converter would work well for maximizing performance.

Cheap high-stall converters will almost always require the motor to come up to the stall speed before starting to move the vehicle. But decent ones (B&M, TCI, Midwest, etc.) will behave very much like a stock converter at light throttle application, but will flash up to the higher stall speed when more (or full) power is applied.

I have a 2400 rpm converter in my El Camino with a mild 400 smallblock. It's a little too low to be absolutely correct, because the motor really wakes up at about 2800 rpm. But it's a lot better than the stock converter was. And adding 3.73 gears helped, too (it had 2.73s in it stock and it was a dog off the line.)

hth,

Ray, thanks for the excellent explanation. When I get my new engine installed and running I will have a better feel for how she runs and shifts. I went from a 1965 327 to a 1985 350 and a different intake manifold. Right now I'm struggling with getting the old alternator bracketry to work. The new intake manifold sits higher and the alternator has very limited clearance. Also the new manifold has lots more unused drilled and tapped holes that will need to be plugged. I will surely have more questions as my engine swap progresses (or digresses). Don