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Well..... I had "one of those days". I'm still trying to figure out how to launch this thing. My first two time trials I was .050 red, both times. The car ran consistent - 7.65 and 7.64 at 91 mph (1/8th mile track). That put me right on the class break though. I was either going to be the slowest car in "Pro Muscle" or the fastest car in "King Muscle". I decided on the latter. Turned out not to matter --- I sure didn't go red, but I was late - .139 on the tree. Then at about half track or so I figured out that apparently after the burnout I'd managed to get the trans in to 2nd instead of Drive because the 2-3 shift never happened and the motor went probably "somewhere" past 6 grand before it registered on me what was going on. (Love those good forged rods). Somewhere around that time it tossed a belt, or both belts - because power steering went away followed soon thereafter by the power brakes (I'm running Hydroboost). It was pretty warm by the time I got it back to my pit spot and was kicking some coolant out of the overflow. So... I put on the spare belts that I always carry, topped off the coolant, and I was done for the day.

Someday maybe I'll make it past the first round :rofl:

Went to drive it while ago to the club meeting, and I -think- the passenger side collector has burned a hole in the short piece of vacuum hose that goes to the vacuum modulator from the steel line - again - because that's how it's acting. I'll let it cool off then go check it. Joy. :(

Bear
 

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Congrats, Bear. At least you're out there doing it. It takes guts, heart, and nerve, all of which you possess in spades. You'll get it dialed in.
 

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Discussion Starter #8
Running without a rev-limiter for now. I had an MSD external on it but after it crapped out and stranded me one night, I took it off. It's been repaired but I still don't trust it.

Sigh.... wondering about the transmission now. I thought I had run the car in 2nd but now I'm not so sure. I couldn't find a vacuum leak in the modulator line, so I pulled the modulator to test it. The trans fluid that came out had a brownish cast and smelled burnt - oh crap. :willy: So I drained the tranny pan (I've got one with a drain plug) and it was the same. The car drove fine coming home from the track - an hour's drive at freeway speeds. I guess I'll change the fluid and the filter and hope for the best, but it's got me worried. I'm going to be out of town on business all week too. I'm really starting to question it - the same shop that took two tries to get the converter right is the same shop who went through the transmission. I thought they were good --- now I'm wondering. I've got a 'spare' sitting on the garage floor, if this one turns out to be fried maybe I'll try building that one myself.

Bear
 

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Well..... I had "one of those days". I'm still trying to figure out how to launch this thing. My first two time trials I was .050 red, both times. The car ran consistent - 7.65 and 7.64 at 91 mph (1/8th mile track). That put me right on the class break though. I was either going to be the slowest car in "Pro Muscle" or the fastest car in "King Muscle". I decided on the latter. Turned out not to matter --- I sure didn't go red, but I was late - .139 on the tree. Then at about half track or so I figured out that apparently after the burnout I'd managed to get the trans in to 2nd instead of Drive because the 2-3 shift never happened and the motor went probably "somewhere" past 6 grand before it registered on me what was going on. (Love those good forged rods). Somewhere around that time it tossed a belt, or both belts - because power steering went away followed soon thereafter by the power brakes (I'm running Hydroboost). It was pretty warm by the time I got it back to my pit spot and was kicking some coolant out of the overflow. So... I put on the spare belts that I always carry, topped off the coolant, and I was done for the day.

Someday maybe I'll make it past the first round :rofl:

Went to drive it while ago to the club meeting, and I -think- the passenger side collector has burned a hole in the short piece of vacuum hose that goes to the vacuum modulator from the steel line - again - because that's how it's acting. I'll let it cool off then go check it. Joy. :(

Bear
Does your track have a test-n-tune day/night? I always worked the bugs out and "learned the car" without the pressure of a race environment. 7.60's is pretty strong for a street car - good job!
 

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Bear, I'm no tranny guru, but I've done a few of them and have been servicing them for a long time. Trans fluid stays bright red for a very, very long time. The only reason for it to lose its color and smell "burnt" is excessive heat. As you know, heat is caused by hard use and heavy loads, as well as internal slippage. The discoloration could be fried fluid, clutch material, or a bit of both. Not to get you down, but if it's an issue this early in the tranny's life, it not last very long. My advise would be to contact Cliff or Jake Shoe on the other forum and see what they think. I think you don't have enough line pressure to the clutch packs,but I'm guessing. In any case, good luck with it.
 

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Given the history, I'm questioning everything now. The same shop built the trans and the converter - the only major assemblies on this car I didn't build myself. I had to take it back to them once because the conveter was way loose - the motor would be north of 5000 rpm as soon as I hit the throttle. They redid the converter and it seemed right, but now this. Now I'm wondering it the real problem in both cases was a clutch that wasn't holding. It was ok for normal driving but couldn't live with full torque combined witb sticky tires. If that's the case, then once I get the trans right I'm going to have a converter that's too tight. Sigh...

Bear
 

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Bear, If you decide to rebuild a transmission....check out CONTINENTAL torque convertors.....they "understand " Pontiacs VERY well!!! Eric:willy:
 

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Discussion Starter #13 (Edited)
After much reading and studying (this book is great: How to Work with and Modify the Turbo Hydra-Matic 400 Transmission ) and getting recommendations from folks over on PSP Pontiac Street Performance . I dropped the car off at Jake's Performance in Sanger for him to go through and do one if his Stage II transmission builds on.

He's also going to tweak the governor to raise ths shift points a little, and add an auxilliary trans cooler. Plus he'll open up the converter and make sure it's not damaged/contaminated.

I was set to do all this myself, but after talking with him I learned that the Trans-Go shift kits are "ok" for most regular street engines but once you start getting close to 500 HP they can have problems supplying enough bite to the direct clutch. He has his own valve body calibrations he's developed for his Stage II builds. Plus, he replaces the rear thrust washers with a Torrington bearing, uses the 34-element intermediate sprag (which I'm supposed to already have, but I have my doubts), and adds an additional clutch plate to the intermediate and direct clutch. We talked quite a bit about the various types of clutch frictions and he convinced me that he knows his stuff. He runs all his builds on a transmission dyno to check them out before delivering them. Add to all the above the fact that a good set of bushing drivers is crazy expensive, and you have the reasons I decided to let him to do the work.

I'll know in a couple of weeks or so.

Bear
 

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Bear, you did exactly the right thing. The trans will be bulletproof and worryfree, and will match the rest of your drivetrain in beefiness. It'll be interesting to hear what he finds when he tears it down. Keep us posted on that score. Can't wait for you to get the car back....I'll bet you'll be surprised.
Jeff
 

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Discussion Starter #15
I'm optimistic. They definitely give me the impression they know what they're doing and that it will be right. Everything Jake said made sense and was logical. That's a curse I have - a logical mind - even though I've not been into a TH400 myself, I've studied them enough to understand quite a bit. I'm a lot happier when things make sense. One of these days I'll tear down that spare and get my hands all up in its guts. :D

Bear
 

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I spoke with Jake Friday. So far, he's found that it did in fact roll the intermediate sprag, and it did have a 34-element one. He said it's very unusual for that to happen to one of those, unless they used a poor-quality (or perhaps a used) sprag. He also didn't like the springs in the direct clutch - said they were way too stiff - and didn't like the way the hydraulics were set up. I'm feeling good about it.

Bear
 

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I"m staying with auto and no trans-brake, at least for now. They are going to tweak the governor for me to put the shift points at around 5500 plus install an aux trans cooler.

Bear
 

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Well..... I picked it up last night after work. I spent a good long time visiting with the owner and learned a lot, and liked what I was hearing more and more - convinced that the guy really knows his stuff.

Then.....
On the way home I noticed oil pressure was zero -- Well, obviously it had pressure and I really knew better, so I figured they'd managed to disconnect the wire from the sending unit during the R&R since it's right there by the trans filler tube. No biggie.

This morning I went out to fix that.
Found the sending unit wire was pinched between the block and the transmission. Well, ok --- it's an irritation but still manageable.
I put the car up in the air.
That's when I found one of the trans cooler line fittings at the trans leaking - pretty bad.
That's when I noticed the trans had a factory pan on it instead of my chrome one with the drain plug. :willy:

Am I just snake-bit when it comes to transmissions in this car or what???? :shutme :mad:

I can't decide if I'm going to be mad or just be defeated... :( :confused

Bear
 

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Update....

Well, ok. I fixed all the problems myself, except for the tranny pan, but I did speak with the shop owner and he's going to get mine back to me as well has 'having a talk' on Monday with his guy who did the R&R.

I reckon I feel better now. :cheers

Bear
 
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