I'm about to replace my busted 700r4 with a th350 and was wondering what size stall i should use with my car. Everything is in the sig. I'm also about to add a lt1 cam and a 100 shot.
thanks,
Derrick

 

Is it for the street or strip? You don't have an aftermarket cam so I assume it is for the street.

With a Turbo 350, with its 2.4x first gear not being as effective as the 700r4's 3.06, I'd go for 2500 rpm. Keep in mind that you want one rated at 2500 rpm for a 305.

If it were a 350 engine it probably wouldn't stall untill you hit 3000 rpm, due to its greater torque. Thus if you buy a 2500 rpm converter that is rated for a 350, it will stall around 2000 rpm on a 305. See?

 

thanks, converters are really weird. I've never seen where it's said for a 305 or a 350.
Derrick

 

You need to talk to the manufacturer for the engine setup they are based on.

I pretty sure both B&M and TCI use a 250HP 350ci for their SBC ratings.

 

Something in the 2500-2700 would work. Neal Chance makes a cheaper style 2500-2700 converter that I've seen work really well in LT1 cars. Precision Industries could build one for your exact combination and car then Once you upgrade to something more powerful in the future they can re-build or restall it for free. Costs more money but they're proven extremely efficient on the street and track. Goodluck!

 

Just out of curiosity, why the TH350? If your car is going to be used mostly for street, I think you would want the 700-R4. It has overdrive and get's you alot better mileage. + I just had my 700-R4 rebuilt and they through in a 9 pack clutch set to make it stronger. The 700-R4 is more expensive, but I think you'll save it in gas in the long run. Just my .02

 

I kind of agree with the guy above. Unless you plan on making 500+ Hp, a good 700R4 will hold.

I just splurged on a "Limited Street" 700R4 Pro-Built. Dana over there really knows what he's doing over there and he claims less than 5% of his stuff comes back for warranty work since they come with a 1 year warranty. He says it'll hold roughly 625hp and he has numerous customers running solid 10's without a hiccup. Check it out and yeah you might save enough gas to pay for the difference on the highway. Goodluck! Any cam desicions yet?

 

Thanks guys but the main goal of this car is to be a strickly drag car. As for the first gear of the th350 not being as effective as the 700r4, doesn't the second and third of the th350 make up for that? For now though i'm just playing around with this 305 because a couple of freinds said i couldn't make it fast. As of now i'm running low to mid 14's i figure i can get it in the 12's with a cam and some juice. For the cam i haven't really decided yet because i didn't want to spend a whole lot of money and i haven't checked prices yet, but we'll see. Eventually i'm going to build a blown 350 for it. any other mod. sugestions for the 305 would be great.
thanks,
Derrick

 

Does anyone know about the gearing question i asked between the 700 and the th350. I know the first gear in the 700 it better than the 350, but doesnt the second and third of the 350 make up for it's not so good first? I've heard that the third gear of the 700 is just crappy. Does this make anysense?
thanks,
Derrick

 

No, third gear is the same betweem both--1.00 to 1.

It is the first to second spread on the 700r4 that is steep, like 3.06 to 1.6x or so. The TH 350 is 2.4x to 1.6x, which will work better with a strip car but requires very steep rear gears, in the neighbourhood of 4 to 1, to compensate.

 

thanks for the help bull that explains a lot. now i've just got to figure out what size stall to get to put me in the powerband off the line.
thanks,
Derrick

 

If it is for the strip only, I'd go to 3000 rpm stall. That'll get you moving

 

The car is gonna be driven a little on the street, but not too much. What do you think a 3000 stall is actually going to stall at?

 

As long as you talk it over with the manufacturer, it should hit 3000 rpm. Actually, most will "flash" to a somewhat higher stall if you nail it from a stop.

If you are easier on your starts it should start moving the car well before you hit 3000 rpm. For a mostly strip car it should work well.

 

well it's really gonna be driven on the street more than the normal "strip car". but mainly on the weekends, and to the street races. but i'll prob go ahead with a 3000. Can you give a somewhat of a powerband on a car like mine?