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Need more convincing that Pontiac's ain't ::cough spit:: chevys? Well consider this:

The TH400 transmission in the beast is one of the few jobs I didn't do myself. A local transmission shop with a good reputation went through it for me and put in all 'the good stuff' including heavy duty frictions, heavy sprag, shift-kit, etc. They said they could also build me a custom converter to my specs, so I said "sure". It was supposed to let my engine flash to around 3200-3500 rpm on a maximum effort launch. I made sure I gave them a copy of my dyno sheet and pointed out the torque numbers on my motor so they'd know what they were dealing with.

I don't think it sunk in.

As I've been getting to know the car, working through issues and stuff, I haven't yet been able to really drive it more than 1 or two seconds at WOT in any gear, even high gear, before it's doing ugly things like bouncing off the rev-limiter and throwing belts. I mean it happens like right now...

Earlier tonight I think I may have figured out part of the reason.

I've been suspecting the converter for awhile, so I tried something. I stopped with the brakes applied, and stood on it. Mistake. In a heartbeat it was almost on the limiter again and.. what brakes? Despite me practically standing on the brake pedal (and it has hydroboost power assist brakes) it still broke both wheels loose just as if I was using the line-lock.

So, I tried again, this time being a little more controlled and easing into the throttle to bring the rpm up in a more controlled fashion. When the tach needed climbed past about 4300 rpm with the car still sitting motionless, I quit. So much for 3200 rpm stall. :rofl:

That, ladies and gentlemen, is what we mean by Pontiac Torque. :cheers

So I guess next week I'll take the beast up to the trans shop and demo it for them. Hopefully they'll 'do the right thing' and put in a converter that's up to the task, then maybe I can get that burnout video happening :lol:

Bear
 

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Bear, all due respect, loading up your trans against the brake like that with the knd of power you have is a good way to do major damage to the tranny. Good thing you got it checked out and got away with it, but you are pressing your luck, IMO. Cliff on the other forum likes the Continental converters....They're $$$$, but suposed to be excellent. I'm running a GM LS-6/spec converter in my TH400, with a stall of about 1800 rpm. But, my cruising rpm is about 2000-2300, and I have about 200 hp less than you do and much less torque. The thing I always liked about Pontiacs, and I'm talking non-stroked ones, (as that's my only experience) is that they do NOT stop pulling. People can not believe how hard they pull in 3rd or 4th gear....and keep on going. I can only imagine a 500hp stroker! Good luck, and be careful....these things can swap ends real fast with road crown, wet spot, etc.
 

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Yessir, it was a concern but I had to know for sure. Funny you should mention the LS-6, a high school buddy of mine called me last night (he's got a really nice Mayfair Maize 65 4-speed packing a 421 that's down right now with a spun bearing I think), and he mentioned the very same converter.

On a recommendation from the other place I also talked with the folks at PTC. He's got one of theirs and says it behaves just like the things I read about the Continental -- nearly indistinguishable from stock until you stand on it, then it flashes to around 3000 -- which is what I want. On the phone with PTC they convinced me they understood the problem and recommended their 10" unit that's set up for nitrous cars :D They're just over half the cost of a Continental. Hopefully the trans shop will work with me on this and make it right, but if not then I've got options.

Bear
 

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.......sounds like you got a handle on it! Yeah, I did a LOT of reading up when I rebuilt the trans last March.....With the 2.56 diff I'm running on the ragtop, I wanted a little help out of the hole but no slippage at cruise....the 1799-1900 stall looked good on paper. In real life, it feels just like the old tight converter, with the exception of much more "oomph" out of the hole. Cliff and Jakeshoe on the other forum seem to be the auto gurus, from what I've been able to ascertain. Good luck with 'er!!
 

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Bear, If you can't get no satisfaction...from your tranny guys. Try Continental Convertors in Cali. (?)....They will ask you all kinds of spec. questions....cam, rear gears, tire height, what the car will be used for, etc...They will build you a superior TQ Conv......They are experts on Pontiac needs....be prepared to pay $1000 for the best one! Eric
 

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Discussion Starter #7
Well, alrighty then. I took the beast by the tranny shop today and performed a little demo for them. They agree it's not right. I'm supposed to drop it off there in the morning, should have it back in a day, maybe two.

Am I nervous leaving it some place out of my sight? :eek::eek::eek::eek::eek::willy::willy::willy::eek::eek:

Yeah, a little... :(

Bear
 

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20 years ago when I dropped the '65 off to the upholsterer to install the headliner, his remark when I picked the car up two days later was "man, that thing really screams!" A test drive after installing a headliner?? No harm done, though!
 

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I have a good friend who watched his 69 SS 396 Chevelle (factory hugger orange) get totalled while the mechanic was on his way back from a "test drive", not knowing my buddy was waiting there to pick it up and chatting with the shop owner. Shops insurance paid on the car, but it was a total.

Yeah, I hate leaving my stuff with anybody. Take the dist. cap with you or something.
 

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Ok... the beast is back home safe and sound. Whew :cheers

I can't really report on the success because it's foggy/rainy/miserable here today and all the streets are wet, but they definitely went in the right direction with it. It's much tighter now in just plain old normal driving.

So, hopefully, it's right.

Bear
 

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Just be sure to keep your foot out of it when the streets are slick and you have a floor jack and some old starter cores in the trunk.....
 

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have a battery kill under my dash but that dont do no good if they need to really test it.....GeeTee, you would'nt have wanted your headliner flapping around when you hit 100 on the freeway....he was just doing a thorough job....:eek: All of the bodywork on my quarters was from a spare tire and jack with no hold down bolt.
 
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