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73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: Zwarge on January 09, 2015, 04:14:05 am
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hello ive got a 1985 c10 with a 462 bbc balanced and stell heads .557 cam with a built 700r4 behind it. I've got the pedals for a mechanical clutch set up but looking for the best manual trans to put behind it. I need an over drive cause I will be doing a lot of highway driving. it is my daily driver in the summer. thanks I've found iroc 5 speeds that are around what I want to spend (0-800) but have no idea the hp or torque they can take. thanks for any input.
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With that BBC, you're probably best served by the NV 4500 5-speed transmission. It came in GM vehicles and is very stout. Here's a link for some general information about the trans: http://en.wikipedia.org/wiki/New_Venture_Gear_4500_transmission
I think other members have performed this swap already. Hopefully, they'll chime in soon.
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You will break a T5 from an IROC, they won't last long behind the BBC.
There isn't going to be anything that will fit with overdrive that will be in the $800 range unless you find a deal on one.
A T56 will work if you want a better ratio trans like a car, but not for $800.
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Yea I've started looking into a 5.3 swap now with a t56 or a tko 600
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I have swapped an NV-4500 behind a BB into my 83 C-10. It has yet to hit the road but am close. The swap was easy but I had all the sheet metal off so it will be a tad more difficult with it all on. You will have to get a different bell housing as the trans to BH bolt pattern is different. I got mine from AdvancedAdaptors by way of Summit Racing for around $400. If you are running mechanical clutch linkage you will also need a $27 AA ( Summit also) part to make it work as the ball connection boss on the BB is too far forward for the stock assembly to hook up correctly. Even with that adapter I had to lengthen the adjuster linkage from the bell crank to the clutch/throw out bearing lever. You will also have to move your original transmission mount back and do some minor trimming as this trans is longer. Also be sure you get a GM tranny from a 92 to 07 3/4 or 1T as Dodge offered the same NV -4500 but with a longer and different splined input shaft and a different out put set up. GM used a ujoint yoke, Dodge used a splined yoke. Also the GM version has no connection for a mechanical speedo cable but uses a VSS signal to run an electrical speedo. I bought a " Reverse" adapter from Dakota Digital ( EC-100 ) $300, that takes the pulses from the trans sender to run an electric motor in the unit. They also supply a shorter mechanical speedo cable with either the srcew on end or the clamp on end depending on which type speedo you have,
Good luck finding a salvage yard NV-4500. They are not made anymore and most of the available salvage yard units have been bought up by commercial rebuilders. I bought mine from Nogalitos Gear in San Antonio. All in all it's gonna set you back about $3500 for the swap. It wasn't that much for me but I already had the flywheel, pressure plate, clutch disc and throw out bearing. You'll also have to get a high hump trans cover and cut out the floor board for it
I also swapped in an Eaton psi unit to the rear end with 3:73 gears so with the .73 ratio 5th gear the final drive should be around 2:72. Should help with the BB ......maybe go from 7 mpg to 9 mpg ;)
Hope this helps. Will report back in a couple weeks when the truck is drivable.