Torque converter stall speed

[turbodave231]

I'd like input on stall speed from anyone running a large single turbo on a S2 headed engine.

I'm struggling trying to build boost on the line with my new engine setup. It pulls like a freight train once the boost comes on. The car is going 131 MPH through the traps and picks up 28 MPH between the 1/8 and 1/4.

My turbo is a BB T-76 and I have a 3500 stall Lupo 9" converter with a 400 trans and a brake.

I know the converter is too tight, But I'm looking for input on how high a stall I should be looking for.

Dave

 

[Quick86GN]

I run a 4500 stall Pro Torque converter with a FB Performance VSC TH400. PT-91 Turbo,No spool problems on a Pro Tree

 

[Nick Micale]

TH 400 Hughes

The converter in my car, and couple other locals, with TH400 running the similar Hughes converter stalls ~4500 and will flash to 5000 RPM.

Took a couple tries to get it right which is common for most combos.

 

[slamming 6]

I have a 8 inch 4500 TCI converter if you need to try one.It has16 runs on it.

 

[turbodave231]

Thanks for the input and the offer....much appreciated, Opeltwinturbo is going to lend me a converter to try out. BG is going to be FUN this year!!!!!!!!

What converters does Bill Anderson use/sell?

Dave

 

[Louie L.]

Bill sells ATI. I had one on my TSM ride and its awesome. Took several tries. Im going to use it on the 260 S2 and see how it works.

 

[TurboTR]

Dave is that an old q-trim? How do you have the spark mapped in the spool zone? And have you done a log during spoolup that shows what rpm it's hitting at 0 psi boost?

FWIW Austin Kendall's S2 heads car was able to come up pretty well even with a converter that only stalled about 2900 at 0 boost (lol) and a 76 GTS. A converter mismatch for a race car for sure, but it would still come up pretty well and get over the hump. The GT turbines seem to come up noticeably better than the q trim.

TurboTR

 

[turbodave231]

TR,

I'm using a Turbonetics T-76 BB Q trim turbo with a .96 exhaust housing.
I need to go back and look at my logs to see what spark and fuel I have mapped in the spoolup areas of the VE table. I'll be changing out my ECU tonight, and I'll look thru the traces and post some numbers.

What works the best? I'd did some searching and didn't find any conclusive numbers for ignition timing or target A/Fs

This car is a pooch out of the hole, but once the turbo comes on the boost, holy sheet..........hang on!!!!

 

[TurboTR]

Ah, a q-trim with .96 a/r no less Yes that one will likely be pretty doggy without alot of converter.

IMO you should target a touch rich of the best power a/f ratio in the spool zone, and make sure it has enough timing to make its best torque as it fights to get over the hump. Some people drop all the full boost timing retard in one big step at some kindof arbitrary load point. In general the map should be smooth, not stepped.

TurboTR

 

[John Wilde]

4500 RPM Neil Chance 10 inch Bolt Together Pro Mod.
Maybe less with the aluminum hub.


Super expensive but the best bar none.