[mels80ga]

I posted this in the street section by mistake. I recently got to the track after changing from a 10 bolt 3.73 rear to a 9" 4.56 rear and I put a TCI 4500 converter in. I had terrible traction but I still had 1.57-1.58 60'. The ET was a little slow but the MPH was down 3-4 from last year. Once the shift light came on it never went off and I couldn't even feel the shift changes. Is it possible for a converter to slip this much? It was a used converter that I knew nothing about but the part # ID was TCI 4500 stall.
Thanks,
Mel

[fasteddy]

Mel, what do you shift at? What is your motor combo? It definitely sounds like you are driving through your converter. Was it behind a SBC? If so, then the answer is yes-it is possible to have that much slip. The converter may need to be opened and freshened and set up better for your combo. My.02

[71 Ventura II]

AGAIN:
Calculate the slippage! What RPM were you turning at the line? vs the MPH? vs Gear

GEAR X MPH X 336= xxxxxxxx / TIRE HEIGHT= FULLY COUPLED RPM (Zero slippage) Now divide the fully coupled rpm by the observed rpm to find the coupling percentage. Subtract the coupled percentage from 1 to find slippage... Example below plug in your numbers...

4.56 X 115 X 336= 176198.4/ 28"= 6292.8 / 7000= .8989 So 1 - .8989= .1011 or 10.1%I've seen converters adding 30% slippage so anything is possible. JD

P.S. Thought for the day "Blowing through a cheap converter"!!! Not cost but quality...

[71 Ventura II]

Originally Posted by fasteddy

Mel, what do you shift at? What is your motor combo? It definitely sounds like you are driving through your converter. Was it behind a SBC? If so, then the answer is yes-it is possible to have that much slip. The converter may need to be opened and freshened and set up better for your combo. My.02

He's running a 455 with a 4.56 gear and a 4500 stall. If it's an off the shelf 4500 behind a 455 it should be stalling 5000+ if not much higher unable to couple the tq of the 455. imo

[mels80ga]

The converter is one of TCI's shelf converters. Not cheap though. They sell new for around $575.00. The engine is 467, 4.56 gears, race wt. is around 3400. I may send it out to be set up for my car. Who would you recommend? I can't tell the exact rpm I was turning because I use an adjustable shift light with the factory tach. It is only a 6000 rpm tach and I had my shift light set at 6000. It is just weird how the car would leave that hard and then drop MPH like it did. Thanks for your input.

[Ron H]

Does your shift light come on at the end of the track?

What was the MPH and ET incrementals of the run?

[Old Goat Racer]

Sounds like a TCI #242300. Put one in my son's car when it ran 12.0.
great 60' but couldn't hear it shift & lost mph.
Gave it to a shop to have it "tightened up" no change?
Sell it.

[71 Ventura II]

Originally Posted by mels80ga

The converter is one of TCI's shelf converters. Not cheap though. They sell new for around $575.00. The engine is 467, 4.56 gears, race wt. is around 3400. I may send it out to be set up for my car. Who would you recommend? I can't tell the exact rpm I was turning because I use an adjustable shift light with the factory tach. It is only a 6000 rpm tach and I had my shift light set at 6000. It is just weird how the car would leave that hard and then drop MPH like it did. Thanks for your input.

All the converter companies I've contacted ONLY work on there own products. If your going to keep the TCI unit you'll need to call them and get a quote for a freshen w/restall. They're located in Ashland, MS. Shipping will be minimal. JD

[grandville455]

Its too loose! Mine is a 4200 conti and u can feel the shift very firmly! Either send it back or sell it

[vin63]

Originally Posted by mels80ga

I posted this in the street section by mistake. I recently got to the track after changing from a 10 bolt 3.73 rear to a 9" 4.56 rear and I put a TCI 4500 converter in. I had terrible traction but I still had 1.57-1.58 60'. The ET was a little slow but the MPH was down 3-4 from last year. Once the shift light came on it never went off and I couldn't even feel the shift changes. Is it possible for a converter to slip this much? It was a used converter that I knew nothing about but the part # ID was TCI 4500 stall.
Thanks,
Mel

Just in case, and since it wasn't mentioned, did you double check and confirm the fluid level of the trans? Things can get a little finicky if the fluid level is low and line pressures erratic.

[mels80ga]

Thanks for the info guys, I think I'll sell it and get a good converter. I have a friend who is going to let me borrow one of his converters for now. The TCI part # 242200. Probably ok for a small block.

[screamingchief]

Originally Posted by 71 Ventura II

All the converter companies I've contacted ONLY work on there own products.

I dunno about that.

I've heard from more than one source that PTC will rework most any brand of torque converter.

I've also heard that some of the guys that work @ PTC used to work for TCI back when TCI still was building a fairly decent product,that was back before they got bought out and TCI grew too big for it's own good,and a quality product became less important than overall sales volume.

So I'd at least give PTC a call before I got rid of that TCI converter.

PTC builds a badass converter,just ask Langer or Pdude.

ptcrace.com.

FWIW

Bret P.

[Torment]

TCI in fact does make very good converters if you get the right one Their Pro-X line runs very well IMHO... Sounds like you bought a snowmobile clutch though! lol

Contrary to what seems like 'conventional Pontiac wisdom' I hear from time to time, you can make a converter too tight - even for a Pontiac!

[Torment]

FYI - not arguing with you SC. We coincidentally posted over one another - and you were quicker...

[screamingchief]

Originally Posted by Torment

FYI - not arguing with you SC. We coincidentally posted over one another - and you were quicker...

That's cool,I know your not arguing,yeah I'd be willing to agree that some of the custom TCI converters are still OK for a good many applications,but most guys dont go that route when they buy from TCI,many of the TCI customers tend to just look stuff up in the catalogs and order those part no.s,and it's that sorta mass produced stuff from TCI that is all pretty generic in nature.

And as such,TCI's "rep" among racers has suffered quite a bit in recent times.

I kinda think the new TCI Pro-X line of parts & converters are an attempt by TCI to regain some of those long lost "hardcore" race oriented customers.

FWIW

Bret P.

[ventura7211]

Originally Posted by screamingchief

I dunno about that.
I've also heard that some of the guys that work @ PTC used to work for TCI back when TCI still was building a fairly decent product,that was back before they got bought out and TCI grew too big for it's own good,and a quality product became less important than overall sales volume.

It was one guy for a couple of months. He is now back at TCI, has been for months now. He rebuilt a tranny for us @ TCI Saturday morning over the labor day weekend after the clutch pack welded itself together Friday during testing.

Originally Posted by screamingchief

I kinda think the new TCI Pro-X line of parts & converters are an attempt by TCI to regain some of those long lost "hardcore" race oriented customers.

All the Pro-X transmissions are assembled by the same guy. Their transmissions are on par with Neals, etc. that are out there. They are working on the converter side but are not on the same level as a Chance or Pro-torque.

[twooldgoats]

Originally Posted by 71 Ventura II

All the converter companies I've contacted ONLY work on there own products. ...

Hughes Transmissions redid my A-1 converter and did an excellent job.

Jim

[Torment]

Originally Posted by screamingchief

That's cool,I know your not arguing,yeah I'd be willing to agree that some of the custom TCI converters are still OK for a good many applications,but most guys dont go that route when they buy from TCI,many of the TCI customers tend to just look stuff up in the catalogs and order those part no.s,and it's that sorta mass produced stuff from TCI that is all pretty generic in nature.

And as such,TCI's "rep" among racers has suffered quite a bit in recent times.

I kinda think the new TCI Pro-X line of parts & converters are an attempt by TCI to regain some of those long lost "hardcore" race oriented customers.

FWIW

Bret P.

Yep the 'off the shelf' stuff probably isn't gonna be the best bet for a Pontiac. I came into a 9" TCI some years back and Butler gave me a direct # of a guy at TCI to work with. I sent it to him for an adjustment and once over and that was the best converter I ever ran... Short tracked like an 8 and pulled like a 10 on top - well not quite on either end but you know what I mean

[71 Ventura II]

Originally Posted by screamingchief

I dunno about that.

I've heard from more than one source that PTC will rework most any brand of torque converter.

I've also heard that some of the guys that work @ PTC used to work for TCI back when TCI still was building a fairly decent product,that was back before they got bought out and TCI grew too big for it's own good,and a quality product became less important than overall sales volume.

So I'd at least give PTC a call before I got rid of that TCI converter.

PTC builds a badass converter,just ask Langer or Pdude.

ptcrace.com.

FWIW

Bret P.

Originally Posted by twooldgoats

Hughes Transmissions redid my A-1 converter and did an excellent job.

Jim

Man I wish you guys would have been around when I wanted my TCI Street Fighter 10" converter freshened and re-stalled. I ended up selling it and buying a Redneck 3500 unit that worked great in my combo on the nitrous. I wish it had a little more flash for the NA runs though. JD