I am going from a vigi 3000/4l60e setup to a th400 this winter. I'm thinking I want something in the 3800-4000 stall range since the th400 doesn't have as deep of a first gear as the 4l60e/700r4.

I talked with coan today and it looks like my best best is p/n 20503. It's an 8" race converter built to handle the t-brake (even though I won't be using right away) and w/ my setup it should stall in the 3800-4200 rpm range. He also said if down the line I build a stroker with a lot more power, then the converter will stall higher thus allowing me to use it even w/ my future plans (383 stroker and some juice ).

He also mentioned that 3800-4200 was a (relatively speaking) small stall speed for an 8" converter so it would be pretty tight thus allowing me to still have good drivability on the street. Plus they are on sale until December 24th. He said I should definitly see some gains over the vigi3000/4l60e setup since the 8" eats less power than the vigi 9.5" (of course the th400 itself eats more than the 4l60e) and the higher stall will help get me moving to at least 1.5's if not 1.4's in the 60'. Also, he said that having a trans that shifts 2-3 without hitting rev limiter would show gains all in itself (like he had to tell me that ). All in all, looks like 11's will be cake w/ this new setup and then once juice is added I might even see a 10 second slip. Craig from coan even said he wouldn't be suprised to see 11.5's on motor once I throw in this stall and the working tranny. I'd be a happy camper then for sure!

 

Spend the extra money and get you another Vig. They make a lock up converter for TH 400 that locks up in 2nd & 3rd.

 

That lockup Vig sounds interesting, I might have tried it if it were designed to handle a really hi-po application, which it is not as far as I can tell. The other issue with it that it requires a special valve body. But it may be worth considering for your setup.

But just to correct a misconception, buying the 8" Coan isn't saving any money. Coan makes a wide variety of converters, but I think the one he's talking about is in the $800 range. I am happy with my Coan, but lockup would be nice.

Rich Krause

 

I'm running a 10" Coan rated around 3000-3200 stall on my 400. I told Coan what the old setup was going to be (Procharger w/ NX wet shot) and that's what they suggested.

Hope the 8" isn't going to be on the street much.

 

Yeah Rich is right on the price range. It would probably be spending less to get the vigi since the coan is in the 750-800 range. I definitly know you get what you pay for in the converter world. The 8" coan is on sale for $675 or something close to that right now.

This car will see a lot of street use. Craig from coan actually said it'd be a good choice going with the 8" because it will be a tight 8" (3800-4200 stall) instead of it stalling up in the 5000+ range if you have it on a big motor and a loose setup.

Mongse...they probably had you get a lower stall because when you're on the juice it will stall up in the 4000 range most likely. I don't plan on spraying off the line (stock 10 bolt rear) so I'll probably hit the switch once I'm in second gear.

Are there any other companies I should consider? What exact converter are you running Rich? Not that it would work w/ my application, I'm just curious as to the size and driveability.

Thanks again guys,
Sean

 

Sean: I am running Coan's "Maximum Performance Steel Stator" 10" (pn COA-20330). I needed a converter that big to get the stall down where I wanted it. Mine stalls at 4,200 without the nitrous. I admit that I haven't had the ***** to try it with the N2O on. Even though the parts are supposed to be up to it, the idea of sitting still with 1,000hp going through the converter up against the transbrake makes me a little nervous.

The first converter Coan sent stalled at ~5,200. That was higher than I wanted. Coan was good about restalling it (new stator). No charge, took a couple of weeks including shipping time. They seemed very willing to work with me.

I was surprised, but even the 5,200 was tolerable on the street. I wouldn't want it for rush hour traffic, but it was tolerable for cruising around the 'burbs. The 4,200 is really not too bad at all. Again, I wouldn't care to creep through traffic with it, it would probably overheat as well as be annoying to drive for long in those conditions. But for cruising, runnning errands, etc. it is really no problem. Just takes a while to get used to.

FWIW, it wasn't cheap. Cost nearly $1,100.

Rich Krause

 

No misconception here. cost me another $1,200 on top of the converter for the front input shaft, pump, and valve body, that has transbrake,and lockup. That was dealer cost.

 

Yeah, yeah. You just want to have the same setup as your Dad, admit it.