Turbo 400 1982 vette
12-09-2018, 03:13 PM
#1
Heel & Toe
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Turbo 400 1982 vette
Hello, has anyone here even and to extend a tail shaft? I’ve got a 1982 corvette with a stroked engine and I’m putting the turbo 400 in but I’ve measured that the tail shaft will be to short, can anyone give me recommendations to a tail shaft I can buy that will fit with the 32spline yoke and u bolts? Or do I have to go completely custom?
Thanks in advance.
Thanks in advance.
12-09-2018, 03:51 PM
#2
Team Owner
Not sure why you would go to the trouble of upgrading the engine and then stick a heavy, inefficient [ but bulletproof ! ] transmission behind it. A well built 700-R4 or 200-4R would be better choices. And they each provide an overdrive gear for highway comfort (.67 final gear ratio). If you are doing it because of low funds and the 400 is available, so be it. Otherwise, IMO it would be a mistake to install a THM-400.
12-09-2018, 04:06 PM
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Not sure why you would go to the trouble of upgrading the engine and then stick a heavy, inefficient [ [b]but bulletproof ! ] transmission behind it. A well built 700-R4 or 200-4R would be better choices. And they each provide an overdrive gear for highway comfort (.67 final gear ratio). If you are doing it because of low funds and the 400 is available, so be it. Otherwise, IMO it would be a mistake to install a THM-400.
12-09-2018, 07:20 PM
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12-09-2018, 09:17 PM
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12-10-2018, 05:41 AM
#9
Safety Car
Hello, has anyone here even and to extend a tail shaft? I’ve got a 1982 corvette with a stroked engine and I’m putting the turbo 400 in but I’ve measured that the tail shaft will be to short, can anyone give me recommendations to a tail shaft I can buy that will fit with the 32spline yoke and u bolts? Or do I have to go completely custom?
Thanks in advance.
Thanks in advance.
12-10-2018, 06:10 AM
#10
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Yeah I’m just trying to workout the quickest cheapest easiest option.
12-10-2018, 07:41 AM
#11
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Still havent answered us what engine are you using?Specs on it?
12-10-2018, 10:53 AM
#12
Safety Car
12-10-2018, 11:02 AM
#13
Race Director
You can't put on a longer tailshaft housing. You need to lengthen your driveshaft. If a longer housing exists, the tailshaft itself would still be about 3.5 inches too short. And there is no add-on overdrive for the T400. If there was, we would not be buying every 700R4 we can find...
Last edited by derekderek; 12-10-2018 at 11:03 AM.
12-10-2018, 02:59 PM
#14
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You can't put on a longer tailshaft housing. You need to lengthen your driveshaft. If a longer housing exists, the tailshaft itself would still be about 3.5 inches too short. And there is no add-on overdrive for the T400. If there was, we would not be buying every 700R4 we can find...
Im not interested in lengthening the drive shaft as it will be weak, I would rather find a longer driveshaft and shorten it?
And they do make overdrives for the th400! Check out gear vendors.
My new motor is 875hp at 4500 rpm for those asking.
Like i I said they 700 would cost to much! Plus I don’t give a **** about overdrive!
12-10-2018, 04:10 PM
#15
Safety Car
3.5 inches!? It fits now as is but it’s prob about 1 inch shorter then original, I want to know then can I use a drive shaft from a earlier model corvette??
Im not interested in lengthening the drive shaft as it will be weak, I would rather find a longer driveshaft and shorten it?
And they do make overdrives for the th400! Check out gear vendors.
My new motor is 875hp at 4500 rpm for those asking.
Like i I said they 700 would cost to much! Plus I don’t give a **** about overdrive!
First at 1" longer too short you could probaly get a longer driveshaft yoke and use the current driveshaft. that being said I have no idea how you are getting 875 HP at 4500 RPM, those numbers are really high for such a low RPM but assuming that is true you will need a custom built driveshaft, the factory driveshaft will never put up with that much power. So just get a new shaft rated for that power level at the correct length.
12-10-2018, 04:16 PM
#16
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A couple different things going on here.
First at 1" longer too short you could probaly get a longer driveshaft yoke and use the current driveshaft. that being said I have no idea how you are getting 875 HP at 4500 RPM, those numbers are really high for such a low RPM but assuming that is true you will need a custom built driveshaft, the factory driveshaft will never put up with that much power. So just get a new shaft rated for that power level at the correct length.
First at 1" longer too short you could probaly get a longer driveshaft yoke and use the current driveshaft. that being said I have no idea how you are getting 875 HP at 4500 RPM, those numbers are really high for such a low RPM but assuming that is true you will need a custom built driveshaft, the factory driveshaft will never put up with that much power. So just get a new shaft rated for that power level at the correct length.
Still would like to know if anyone knows of a different model corvette with the longer drive shaft then my 1982 model that I could bolt straight up onto mine with like only having to change the yoke?
12-10-2018, 05:38 PM
#17
Team Owner
Your auto place sold you a bill of goods....a THM-400 which no one else wanted. You can't put an overdrive gear into a 400. You can ADD a pricey reduction gearbox behind it, but that will double your cost and you will have to modify your undercarriage to install it.
You could have gotten a fully built 700-R4 or 200-4R for about the same money that you paid for your 400. SALES places want to SELL you stuff. And they really want to sell the stuff that they can't sell to anyone else. Sorry. But you got a bad deal with this one.
Going forward, your 400 is a solid unit, but will not be the performer that O/D units would be--and certainly will be a gas guzzler in city and on highway. Hope you are OK with the result.
You could have gotten a fully built 700-R4 or 200-4R for about the same money that you paid for your 400. SALES places want to SELL you stuff. And they really want to sell the stuff that they can't sell to anyone else. Sorry. But you got a bad deal with this one.
Going forward, your 400 is a solid unit, but will not be the performer that O/D units would be--and certainly will be a gas guzzler in city and on highway. Hope you are OK with the result.
12-10-2018, 05:46 PM
#18
Race Director
Yes. Any Corvette driveshaft from the T400 era would fit. I was going from nemory in length diff. Maybe I am thinking of the Borg T5 compared to standard Corvette stuff. Everything from driveshaft yoke to wheel studs has to be built to take that much power.
12-10-2018, 07:02 PM
#19
Safety Car
I tried that first, the two places I called said they don’t make longer 32 spline yokes.
Still would like to know if anyone knows of a different model corvette with the longer drive shaft then my 1982 model that I could bolt straight up onto mine with like only having to change the yoke?
Last edited by bjankuski; 12-10-2018 at 07:15 PM.
12-10-2018, 07:25 PM
#20
Le Mans Master
Some good info here, seems like an earlier shaft is longer, 82 is 25" long.
https://www.corvetteforum.com/forums...ft-length.html
https://www.corvetteforum.com/forums...ft-length.html