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350 to 454 conversion

Old 05-23-2013, 03:05 PM
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Default 350 to 454 conversion

I have converted my small block 73 vette to a big block. Have tackled most of the problems, such as additional heat under the hood, and some bracket alterations. Just wondering, will the 4 speed transmission and small block rear gears hold up under the additional torque?
Old 05-24-2013, 09:50 PM
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AFAIK there is no difference in the rest of the drivetrain. I do remember that the half shafts were larger on auto trans vs manual. If your BBC is hipo, might want to replace the rear diff cross-member rubber w/ solid mounts. With more power, be prepared to find the weak link.
Old 05-30-2013, 03:36 PM
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If you haven't, change all of the "U" joints, drive and axle shafts.

Like 73shark says, Ya wanna hit the weak spots.

Don't overlook the trailing arm bushings.
Any mounting bushings for that matter.
Set the emerg brake,
Jack up one rear wheel at a time.
Now try to wiggle the tire side to side, front to back.
IF you get any movement you need to look deeper.

If you don't set the emerg brake, any looseness top to bottom
AND side to side shows a bad wheel bearing.

Another trick and more reliable IMHO,...

Measure between the tire rims, front to back, on both sides.
Put the car in reverse and move briskly backward about 3 ft.
You don't have to burn rubber.
Easy on the brake when you stop.
(Slamming on the brake may nullify the effects of the
thrust. If it is loose, it may move back to the original
Measure the distace between rims again.
Did it change?
Now do the same thing in 1st.
Measure again.
Any dif?
That's going to tell you if you have wear on the swing arm bushings.

All I'm doing here is showing a way to detect wear, not how much wear.
If it's loose, it needs to be tightened or Replaced.
You replace bushings, no way to tighten them.
Adjustments for the trailing arms is only for the entire axle/wheel to move
forward or back in order to line up parallel and perpendicular with the other
side and front.

Hope that helps.

Last edited by C3 Starship; 05-30-2013 at 03:45 PM.
Old 06-01-2013, 08:52 PM
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Thanks very much for the information concerning the drivetrain on my conversion. Since it is not hipo I may not have immediate stress problems.
Old 06-18-2013, 11:08 AM
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Location: Reno, Nv.
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You'll need dif brackets for your alt, ps, ac.
Brackets from a SB will not work.
Pay attention to the water pump and pully line up.
You'll need a short shaft pump for the fan to clear the radiator.
AND a "Vette specific" oil pan.
Far as I know, only Vettes used a specific design
oil pan due to the possition of steering componants.

Last edited by C3 Starship; 06-18-2013 at 11:10 AM.
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