Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

Hi there,

I'm looking for advice and recommendations for which brand of torque converter and what stall speed to order for my car. It is a 1989 GTA with a 350ci ZZ4 crate engine.

Other modifications include:- Hooker 2210's, Lingenfelter throttle body, Lingenfelter Runners, ported plenum, custom prom, true dual 2.5inch exhausts, underdrive pulleys.... and every suspension upgrade you could ask for!

This below linked thread from a few years back has one guy recommending an Edge 2800 and another getting a 10 inch Midwest 3000rpm converter.

What's a good ZZ4 engine stall converter?
https://www.thirdgen.org/forums/tran...z4#post2209532

I'm personally leaning towards a Vigilante multidisk with full throttle lock up, but I have no idea what stall speed to go for.

All opinions are welcome,

Many thanks!

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

What are your goals? Street or strip? What the rear gear? What kind of tires are you going to run on? When you say suspension upgrades, what exactly do you mean? Choosing a converter should depend some on the availible traction you'll have. TPI makes such good torque I wouldn't think you'd need to go too wild, 2800-3000rpm should be fine unless you're a strict drag-race application.

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

call up tci and tell them your specs, they'll help you out.

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

"What are your goals? Street or strip?"
2000-3000 hard driven street miles per year with some trips to the strip in the summer months. Currently I'm running over 350bhp/400lb ft, and am planning on some more engine changes and a D1SC Procharger to get me up over 600bhp in a few years time.

"What the rear gear? What kind of tires are you going to run on?"
Stock 3.27 9 Bolt BW rear end. Currently 255/50/16 and 245/50/16 Kumho Supra 712's. Will eventually change to a Moser rear and drag radials.

"When you say suspension upgrades, what exactly do you mean?"
Koni Yellow struts and shocks, Eibach springs, Spohn adjustable tubular CM LCA's, LCARB's, adjustable torque arm, Spohn K-member and A-arms, adjustable panhard rod, poly bushes throughout, adjustable strut mounts, wonder bar, 2 sets of SubFrame Connectors - Spohn and Alston, etc etc.

Thanks!

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

Unless you're going to get radical with the cam, I can't see needing over a 3000rpm stall for street use. I'm sure with the TPI setup the power comes on real low, so the converter isn't as critical a factor to your launch as say a 302 with a massive cam...

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

2800 is all you need for a TPI zz4. 3000 if you want more drag racing use for best ET's. i'd go with Edge or Midwest for a good quality midrange price converter. vig and precision industries are high dollar units so if you can afford it go with it. I love my Edge tho

i cut low 1.7's with stock L98 with full exhaust and 2800 stall.

if you plan on a procharger that 2800 stall will be great still sicne TPI will make the torque between 2800-3200rpms, and with the blower its gonna be even more torquey

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

Thanks guys!

Orr89RocZ:- Where did you get your Edge from?

All opinions/experiences are welcome!

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

i called Edge directly. they will custom make a converter to fit your application.

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

I contacted Edge and must say that I am hugely impressed with their response. Here is a copy of their response:-

"Hello Gordon, and thanks for inquiring,

I recommend a custom configured converter from our "Street Edge"
series with stall math set at 2800-3000 rpm, and STR set at, or near 2.45.
This converter uses the 245mm (9.5") impeller and turbine (furnace
brazed). The 9.5" impeller is the most efficient impeller ever adapted into
performance applications. With 8 impellers and 8 stators to select from
this converter can be truly custom configured with no cutting or bending
inside the converter. This means better launches are a guarantee, better mid
range response is guaranteed and no excess heat or loss of topend,
guaranteed!

All the gains while retaining 100% of the manners needed for every day
street use! All wear surfaces are fitted for enclosed Torrington bearings for
less drag and improved longevity in performance application. The drive hub
and spline insert of made of 4130 chrome moly steel. The lock up feature is
upgraded using the latest "high carbon" friction and anti balloon measure is standard.

Warranted for a full year with our 100% money back satisfaction
guarantee. The "Street Edge" 700r4 /4L60-e sells for 525.00 plus shipping
(Priority mail to the UK is 118.50)

Current build time is 3-4 business days."

"Hello again Gordon,
The quoted postage is via USPS priority air.
You will receive the converter and new fasteners. This is a direct
bolt on and will replace the OE converter with no modifications. The lock up
will be the latest "high carbon" friction, and anti balloon measure is
standard."

Orr89RocZ:- How long have you had your Edge? Does the one they recommend sound good to you?

Re: Which torque converter and stall speed should I use for ZZ4 engine with TPI?
 

i've had mine probly for 3 years now and its been fine. i think you'll like that converter. Not sure what my STR is but 2.45 is pretty high for a converter. that will multiply the torque alot and realy hit the tires hard. i would think a more typical street car would have a lower STR but i'm not sure so you'd have to ask about it.