Do I need a Stall converter???

[Bruceynz]

Hi Guys,

Ok I posted some video of my testing yesterday, I need some advice if you think I need a 2500 stall converter.



I watched this video a few times and clicked onto the way the engine was performing
I Say "1000, 1500, flat to the floor", then if you watch the second timer you can see at 4 seconds I say "flat to the floor" and then at 5seconds the engine comes on song and flys! I am assuming that's when my cam comes in and the power starts to build quite quickly! I never took it all the way in first gear, still had more to go in it in that gear!

I think if I had a stall converter to come in closer to where the engine comes on song that this 360 would fly, let me know what your thoughts are.

Just a thought, the revs picking up is not the secondary's opening is it?


Thanks
Bruce

 

[Steve2961]

I've always chosen the stall speed for a converter based on the cam specs. A good rule of thumb is a stall speed that's 500 RPM above when the cam comes in. For example, if the cam manufacturer lists an RPM range of 2000 to 6500, the converter needs to have a 2500 RPM stall speed. No this isn't scientific and things like vehicle weight, engine torque and gear ratio effect the actual stall speed, but's it's still a good rule of thumb. If the cam's stock, a converter with about 1800-2000 rpm isn't too bad in a performance application.

 

[Aspen500]

I'd say a converter with an advertised stall speed of about 2,500 would work well.

You're driving on the wrong side of the road

 

[BudW]

And all of this time, he thinks we are driving on the wrong side!

Was the engine rebuilt there before going into car?

 

[Bruceynz]

Engine was built in the USA, I bought off craigslist from a guy in California, Engine was in a 1972 charger and was removed for a 440 to go in!

Here is the guy here and that yellow charger is the car my engine came from

March 2014 Highlight: Dan’s Cars | HotrodHotel.net

The engine was done when he bought the car, he said he did a few street races in it and it went well. Drove it to work for a short time then parked car up for resto and or sat for 4 years.

 

[Bruceynz]

I have only managed to find 3 places that sell lockup stall converters

Chrysler A904 Torque Converter 30RH 31RH 32RH TF6 Lockup 225 318ci Engine High Stall 1978-On

A904 high stall torque converter 2200-2500 26 SPLINE (LOCKUP) 1 year warranty

and I came across a TCI one at about $400 but can't find it now, was on ebay. I am thinking the Torco one at this stage if I was to buy one.

 

[BudW]

It is a bit of work, but if it was my car, I would advance the camshaft timing (which is different than ignition timing) a couple of degrees, first

It will lower the powerband about 500-1000 RPM making it more fun in town. Maybe even enough to retain the current torque converter.

If that didn’t do it, I might consider a different camshaft (or torque converter) then.

I’m not there so don’t get the whole picture – but for what I do see, it looks like running pretty well.

I’d rather have a bit of bog than tons of tire spin – unless tire spin is the objective (like the mates West of you want).

BudW

 

[BudW]

Look for a 500 Torque Converter (which is a 904 lockup with overdrive).

It will only come with the different style hub (slot vs. notched) but with a new set of transmission front pump gears (and valve body seal kit) that can be changed.

 

[Bruceynz]

Well thats the thing if your not spinning the wheels but just chirping on take off are you getting good take off??

The thing winds up thats for sure as you can see in video, I know a video doesn't show it all but you can see things start going past pretty quick in a short time.

 

[BudW]

I have friends who are making so much power that they wish they had your problem.

I have a feeling my big block transplant might have so much power that tire spin may be an very big issue – which is not what I want, even with a mild build.

I think hook up is the key word.
A bit of fine tuning (camshaft timing), will fix the bog, or take a big bite out of it.

 

[Bruceynz]

Ok so maybe its pretty good where it is! Just stand on it and it will go, it doesn't take long to build and go, great power for over taking!!

 

[Bruceynz]

I don't want to have to take the trans out, its a prick of a job to be honest, the bell housing bolts around the top are near impossible to get to! Takes about 2 days to undo them moving the spanner at a 100th of an inch at a time.

 

[BudW]

Camshaft timing and ignition timing are two completely different items.

You have to remove the timing cover and either have a multi keyed camshaft gear or have offset keys to set camshaft timing.

 

[Bruceynz]

I might just leave it, if you going along say 20mph and stand on it she is great!

 

[Bruceynz]

OK my friend from Australia is over here, he said I have trans issues with kick down, said engine goes well! But in drive its as flat as a turd! Shift it manually and goes well. He thinks I need to take it to a trans shop.

I have made the 2bbl linkage connect up to the 4bbl carb using a holley adapter, this setup must be quite critical.

Is the only way to sort this to find a 4bbl linkage?

Thanks
Bruce

 

[80mirada]

The 2bbl linkage can be modified to work no problem. The Trans shift points can be changed, the best way is a governor weight change.

A and A transmission: Governor Kits - A&A Transmissions

There are two sizes of weights available, but all early trans should be the small weights, the large weights were introduced in the 90s.

As for a higher stall convertor, TCI Breakaway 141350 would give an approximate 2000rpm stall (should be a little higher on a 360, maybe 2200rpm). A 2500rpm approximate stall would probably be a better choice, but the TCI was the first one that came up

https://www.summitracing.com/parts/tci-141350/overview/

 

[BudW]

I could be mistaken – but I thought the governor weights on the 904 series (904/998/999/500) were different size than the 727/518 series transmissions.

BudW

 

[80mirada]

If I remember correctly, the 904 series use the small weight and 727 did until late 80s early 90s, could be wrong. A&A provided a set for a 904 a couple of years ago that were made for a 6000rpm upshift.

I'm still looking for my kickdown diagrams....

 

[AJ/FormS]

A higher stall TC will only help you get going below about, it's rated stall.IE, from a standing start. Cruising along at above it's stall, and flooring it, will hardly make a difference.
If you are not getting any tire-spin now, you would probably benefit from a higher stall.
If you are getting some tire-spin now, you are already in the ballpark.
If you are getting a lot of tire-spin, you don't need a stall.
If you want more tire-spin,and earlier, get a higher stall.
If you can feel the vacuum secondaries opening, then they are probably opening a little early.
Bud's advice about advancing the cam is a good idea,unless it is already advanced. Only one way to tell.......
Good luck