Choosing a converter with unknown transmission

[Jon Early]

Hey guys,

I ran into a small snag. I have my stock '86 engine out for some cleaning, maintenance, and mild upgrades. Short block, heads, cam, and intake are stock. I upgraded the valve springs to comp 980s, the turbo is a TA49, and I'll be running the car on E85 with 80#. The stock transmission was rebuilt by an unknown builder with a no-name converter before I bought the car. It shifts pretty hard, but I don't know anything about it. I called Hartline and got their custom converter order form and didn't really know what to put for my max and shift RPMs. Is this something only the transmission builder could tell me? How would I determine this for the most favorable results? I'm not looking to build a drag strip hero out of this thing if it makes a difference. I just thought that upgrading the 2200 stall balloon would help my turbo spool a little quicker. I'll take any advice I can get though. Thanks!

 

[Nigel]

With a stock long block and a TA-49, stock shift point are good. They were 4900-5100 rpm. Me personally with that combo I would want 4900 or even a little lower. My input would be Dave Husek's 3021 LU would be a good choice, if you go NLU, then PTC. I would err on the tight side with a stock long block/TA-49, again just me. How does the existing one work?

 

[Jon Early]

With a stock long block and a TA-49, stock shift point are good. They were 4900-5100 rpm. Me personally with that combo I would want 4900 or even a little lower. My input would be Dave Husek's 3021 LU would be a good choice, if you go NLU, then PTC. I would err on the tight side with a stock long block/TA-49, again just me. How does the existing one work?

Thanks for the input. I'd for sure get a lock-up. It's hard to judge the existing one because this car has had a lot of other issues like cracked headers that I'm fixing now.

 

[SCOOBY DOO]

I'd go with Huseks 3021 for what you're doing, but that's just me.

 

[Jon Early]

I'll call Husek's tomorrow and see what he thinks.

 

[Mr.Spool]

Hey guys,

I ran into a small snag. I have my stock '86 engine out for some cleaning, maintenance, and mild upgrades. Short block, heads, cam, and intake are stock. I upgraded the valve springs to comp 980s, the turbo is a TA49, and I'll be running the car on E85 with 80#. The stock transmission was rebuilt by an unknown builder with a no-name converter before I bought the car. It shifts pretty hard, but I don't know anything about it. I called Hartline and got their custom converter order form and didn't really know what to put for my max and shift RPMs. Is this something only the transmission builder could tell me? How would I determine this for the most favorable results? I'm not looking to build a drag strip hero out of this thing if it makes a difference. I just thought that upgrading the 2200 stall balloon would help my turbo spool a little quicker. I'll take any advice I can get though. Thanks!

View attachment 391045

Call dave for sure he can build you a great converter.
But a 49 doesnt work with a 2200 stall even with a tight .63 garrett housing.
Intial stall at 2800 will work,3200 is fantastic with a 49 turbo
Great off the footbrake and will hit like a supercharger.

 

[Jon Early]

Thanks everybody. I had a nice chat with Dave last night.

He proposed two options, and one of them kind of surprised me. Of course the 3021 came up. He said he could build me one, but it would take 6-8 weeks due to parts shortages. That was a big yikes for me because I really want my wife to drive this car to the Nats in May and need everything sorted long before then. I also had plans for some folks from the Indiana chapter GSCA to come help me install the engine in a month from today. I of course want the best part for my application and driving style though, so I'll do what I have to do. However, this wasn't the surprising option.

Dave also seems to think that he has an old school NOS 12" that would be even better for me. While I am not super thrilled about having an "old" converter in my car, I remember hearing/reading a lot of great things about the old 12" converters from back in the day. Some people still say it's their favorite converter, and Dave said he would sell it for quite a bit cheaper than a new custom piece anyway. This idea sounds like a lot of win to me. Dave said that the 12" should light up a TA49 with E85 and my bigger exhaust really quick, give me great street manners, and still kick but on the track on the rare occasion that I want to do that. I think he gets me!

 

[SCOOBY DOO]

Are you referring to the stock D5 convertor?

 

[Jon Early]

Are you referring to the stock D5 convertor?

To be honest... His quick New York talking was a lot for this midwestern guy to take in. What I caught was that it's an old converter that Red Armstrong some other racers used back in the day. It's a 12" LU with about a 2600 stall. Not a stocker though. I'm trying to do some more research on it, but nobody makes them anymore. I'll try to get more out of him when we talk again at noon. He said he wasn't at the shop when he called me, so he has to look for it and see if he even still has it.

 

[SCOOBY DOO]

For what you're doing the stock D5 convertor will work just fine. Convertor technology has come a long way. If time wasn't a deterrent, then I'd say wait for Daves convertor. I'm not sure what Erics default timing is for E85 vs pump gas as we can't get it up here.

 

[Sweet6]

I would wait for the good converter too. It is night and day different from a 12" restalled or whatever it is. The 12" can work good with the small turbos like others have said. But everything has to be right. The better converter will be much more fun on the street too.

 

[Mr.Spool]

wait for Dave's converter.
never go tight with the smaller turbos setups and stock motor stuff
they only shine really in the 1st 500ft anyway
and the turbo makes the low lift low rpm cam bigger anyway.
so looser stalls favor faster 60 and 330 ft
not to mention the looser stall responds so much better on on power on tap throughout the rpm range.

 

[Jon Early]

Too late I'm afraid. I ended up getting the re-stalled D5. It has an anti-balloon plate and custom stator. Not bent fins. I trust Dave's judgement as I'm sure he would also rather sell me a smaller and more expensive converter if he thought it was the right thing for my car.

I feel like there's little to loose. My trans is still pretty unknown. I'm sure this converter will be miles better than what I already have. If I smoke the trans and ruin the converter, I'd rather it be on the cheaper side!

That long lead time wasn't adding up to success anyway. I need this car to be ready for my wife to drive to the Nats without me. I'll be driving another car a couple days earlier.