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Ross
02-08-2001, 03:59 PM
I would imagine that a common swap in our vans would be a small block Chevy engine with either a TH-350, or a 700R4.
Can anyone tell me about how long the driveshaft would be after such a swap? That would be keeping the motor mounts in the stock position.
I am also sure that moving the stock motor mounts rearward would enter the swapper's mind. How many inches rearward could you move the motor mounts and still have a usuable drive shaft?
Ross in Boulder Colorado
Jeep69CJ5@Juno.com

Vandalizer
02-08-2001, 04:09 PM
I swapped out the powerglide in my 68 for a TH350 short shaft trans. The same driveshaft and yoke matched up with no problems.

greg showers
02-08-2001, 06:08 PM
i replaced the six cylindar that was in my 69 and replaced it with a 350 with a 350 trans . the trans is a short tailshaft. it still uses it's original driveshaft.

vannman67
02-08-2001, 07:27 PM
Hey,

I just recently installed a 700r4 in my 67 Sportvan 108. I dry fitted the old driveline and it appears as though about two to three inches would need to be removed from the driveline in order to make it fit. As far as moving the engine mounts rearward. I suppose you could do it but as it sits right now, I only have about 3/4" clearance between the trans bell housing and the hole in the floor. I suppose you could cut the sheet metal, but then you would be left with a gap where the doghouse didn't meet the floor. I'm just planning on having a new driveline fabricated for my application. Since I've already got about seven thousand into my restoration, I figure another $250 isn't going to kill me.

AJAX
02-08-2001, 07:50 PM
IF YOUR PAYIN' $250.00 TO GET A DRIVE SHAFT CUT, I'D SAY SOMEONE IS MAKIN' SO GOOD CASH AT YOUR LOCAL MACHINE SHOP. THE LAST ONE I HAD SHORTENED COST ME $87.00 PLUS TAX CANADIAN. (THAT'S ABOUT $15.00US) NOW TO LENGTHEN A DRIVE SHAFT IS ANOTHER STORY. JUST A SUGGESTION BUT I'D SHOP AROUND. GOOD LUCK! AJAX

prostreet65
02-08-2001, 08:37 PM
I'm also still wondering how short you can
make a driveshaft without having problems...
Ajax???...

AJAX
02-08-2001, 10:09 PM
IN 1976 I DID A 550HP Z-28 302 MIDENGINE IN A 65. HAD A 3" DRIVE SHAFT. WAS TO SHORT. EVER TIME I WOULD PUT MY FOOT INTO IT, THE FLEX AND THE DROP WOULD RIP OUT THE UNIVERSALS. HOW SHORT CAN YOU GO? DEPENDS HOW STIFF YOU REAR SUSPENSION IS. I SAW A VAN AT SOME TRUCKIN' ONCE, THE GUY HAD THE ENGINE,TRANNY AND REAR END ALL MOUNTED TOGETHER ON A PIVOT JUST IN FRONT OF THE MOTOR MOUNTS, KINDA LIKE BIG LONG SWAYBAR, TRACKBAR COMBINATION. EVERY WILD. BUT LIKE I'VE STATED IN THE PAST, IF YOU ARE GOING TO MIDENGINE,THE BEST SOLUTION IS A CORVETTE OF JAG REAR END. THIS ELIMINATES ANY DRIVESHAFT PROBLEM, GIVES YOU MASSIVE BRAKING AND OUTSTANDING HANDLEING. NOW JUST HAVE TO PERFECT A DESIGN TO MOUNT CORVETTE FRONT SUSPENSION INTO THE VAN, BUT THAT'S A WHOLE NEW STORY.

Yeggster
02-09-2001, 12:50 AM
I have the TH350 and 350 4 barrel set up......I moved the engin back a bit too altough I;m not sure how much?

With the 14 bolt rear end I needed drive shaft bigger then the stock thin one..........plus the tranny was out of a 89 Capris and the rear end out of a 76 pickup..

It's about 20" of tube maybe a bit less......I just cut off the pick up drive shaft and then stuck the cut off Capris drive shaft in side it (they fit like a telescope) then welded it together

New u joints and everything I think it was $25 or so......no bad vibrations even up to 5200 RPM shaft speed



[This message has been edited by Yeggster (edited February 20, 2001).]

painterchris
02-09-2001, 10:01 AM
I also think that $250 is way too much for a driveshaft job. A buddy of mine had one shortened and balanced a few years ago for $10.

Later,
Andy.

vannman67
02-09-2001, 07:18 PM
I guess I wasn't very clear in my post. I plan on having a new driveshaft manufactured to go in my van. I'm not so ignorant as to pay $250 to have an old steel driveshaft shortened. That kind of money gets me a brand spankin new shaft.

Vanner68
02-10-2001, 05:06 PM
Hate to say it, but I think $250 is high even for a new driveshaft, unless it's aluminum. I had a new one made up for my 86 dodge after an idiot bent it on a garage hoist, I still only paid $125.

As to how short- the front driveshaft on a 4WD Ford ranger is about 30" long, that looks to be about the shortest reasonable shaft that allows full suspension movement

TurboVan
02-10-2001, 09:14 PM
I would say probably no shorter than 12 inches, and that's only if you have an ideal tranny/axle relationship (not much angle). My Turbo400/12-bolt shaft is about 18 inches now, and I'll have to shorten it again to install my 700R4. A shop near me (in Ventura, CA) recommends 3 degrees up angle on the axle, and 3 degrees down angle on the tranny, with 2 inches maximum difference in height. Otherwise, the U-joints get thrashed. --- TV

TurboVan
02-12-2001, 07:09 PM
Maybe we should ask Willy Montgomery (`64 in GALLERY). His engine is moved back 2 1/2 feet! --- Willy?

Yeggster
02-12-2001, 11:47 PM
Drive Line Specialtys sells 8" long "precsion drive shafts"

Yeggster