Recommended stall speed?

[V8 Rumble]

Fti converters is what I used. I gave the my cam specs, rear ratio and I think tire diameter and they gave me a recommendation. I'm using a 2800 stall in mine.

 

[motorheadmike]

Fti converters is what I used. I gave the my cam specs, rear ratio and I think tire diameter and they gave me a recommendation. I'm using a 2800 stall in mine.

I called FTI this afternoon to discuss the converter for the 4L80E swap in the wagon. Like you I gave them some basic specs (cam, NAWZzzz, gears), my experience with that is in the car now, what I want to do with the car (cruising and Drag Week), and my expectations. They came back with a billet 9.5", triple disc, soft hit, 2:1 STR, and 3800 stall speed. In short, it is good daily converter because of the tighter STR, but will eat up a lot of power from a power adder with the converter locked up at WOT.

PN SR-LS-46391-3 https://www.summitracing.com/int/parts/fti-srls46391-3/overview/

 

[Dinosport]

If you are confident in your tuner's abilities then there is no reason not to go bigger with your TC selection.

If you haven't seen it already... here is something to chew on: https://ls1tech.com/forums/automati...e-converter-stall-torque-ratio-str-guide.html

FTI offers a pretty wide selection through Summit: https://www.summitracing.com/int/search?PageSize=100&SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=fti 4l60e&N=4294949305

I thought it was alot simpler than that. lol. I still havent been able to finish reading that whole thing. I guess I should figure out if the converter guy can just build it according to my set up.

 

[Texas82GP]

I have the gmpp Hot Cam in the 5.3 in my 08 Sierra RCSB. I have a Circle D 3200 in front of my 4L70. I find it to be very streetable. It isn't extreme at all like it sounds. I have 4.10 rear gears but I'm running a 31.9" tire, if that puts it into perspective. I did the "Ask Circle D" form and went with their recommendation
http://www.circledspecialties.com/askcircled
Their facility is here in Houston and I toured it when I exchanged my converter (they offer an exchange service when you have the converter out - in my case for a transmission overhaul at 120,000 miles). It's a nice facility. They have some nice 3-axis CNC machinery.

The converter I went with is just a step above the entry level unit but I've run them a combined 70k miles with pretty spirited driving and had no issues...
http://www.circledspecialties.com/4l60-hp-series-278mm

 

[motorheadmike]

I thought it was alot simpler than that. lol. I still havent been able to finish reading that whole thing. I guess I should figure out if the converter guy can just build it according to my set up.

There is a lot to it. This car had a "3300rpm" stall in it... on the transbrake it would go over 4000rpm - but, yet it was still tight enough to autox with. That converter was a 9" and was connected to a TH400... and still got 18mpg in mixed conditions. To date it was the loosest converter I have ever driven... and it was fine everywhere I took it.

Back when I first started racing that car in autox I had a custom 2000rpm stall made for it - sucked at the drags but worked great around cones.

 

[pontiacgp]

my dumb question of the day.....with a stall speed over the rpm of the cruise speed of 60 mph if you drove the car at 60 mph would the TC be slipping as you drove causing it to heat up?

 

[motorheadmike]

my dumb question of the day.....with a stall speed over the rpm of the cruise speed of 60 mph if you drove the car at 60 mph would the TC be slipping as you drove causing it to heat up?

Maybe.

We are talking about a hydraulic coupling here so that is going to be influenced by a series of factors:

A torque converter consists of three parts: a pump (impeller), a turbine (runner) and the stator in between. As the torque converter rotates, the pump spins and the centrifugal force generated causes the fluid inside the torque converter to be forced outwards and onto the blades of the turbine, making it spin in turn.

Buy a budget converter and prepare yourself for budget problems. A huge contributing factor that is often overlooked is the fluid used. I actually used high-viscosity hydraulic fluid in my Buick to tighten it up. If you run Dex 6 you may find yourself on the wrong side of slippage at speed.

Ironically my cruise rpm at 60-70mph in the Buick was very close to the advertised stall speed. So... it is better to speed then it is to let your trans overheat.

 

[pontiacgp]

Maybe.

We are talking about a hydraulic coupling here so that is going to be influenced by a series of factors:


Buy a budget converter and prepare yourself for budget problems. A huge contributing factor that is often overlooked is the fluid used. I actually used high-viscosity hydraulic fluid in my Buick to tighten it up. If you run Dex 6 you may find yourself on the wrong side of slippage at speed.

Ironically my cruise rpm at 60-70mph in the Buick was very close to the advertised stall speed. So... it is better to speed then it is to let your trans overheat.

thanks, great reason to speed..🙂

 

[Z48LT1]

I'll try to out-dumb pontiacgp with my question. How does "lock up" affect his question of TC slippage at cruise when stall RPM exceeds cruise RPM? I was hoping lock up would make that problem go away entirely.

Is that dumb enough?

Cheers - Gary

 

[motorheadmike]

I'll try to out-dumb pontiacgp with my question. How does "lock up" affect his question of TC slippage at cruise when stall RPM exceeds cruise RPM? I was hoping lock up would make that problem go away entirely.

Is that dumb enough?

Cheers - Gary

Within the physical limitations of the holding capacity of the internal clutch(es), and the supporting hydraulic pressure supplied, that is correct. This applies both at cruise and under load/WOT. The goal is to eliminate slippage.