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400/451 Stroker conversion question

TacticalDawson

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Hey all!

So im thinking of grabbing the stroker kit from 440source and im wondering what/if anything needs to be done to the front/rear suspension and transmission if we turn the 400 into the 451 and what advice you all might have when it comes to suspension work for the 451 if it needs to be done at all.
 
Hey all!

So im thinking of grabbing the stroker kit from 440source and im wondering what/if anything needs to be done to the front/rear suspension and transmission if we turn the 400 into the 451 and what advice you all might have when it comes to suspension work for the 451 if it needs to be done at all.
What did the car come with from the factory? 318 and 904?
 
Unibody cars can always benefit from stiffening the Body, frame connectors help.

Would also recommend replacing torsion bars and springs if they are old. Increase bar diameter and use HD rear springs with extra leaf on passenger side to help with increased torque.

Expect to pay for transmission that will hold to increased power. If rear axle is 7 1/4, will need to replace with 8 3/4 or Dana for increased torque or baby the car to not break rear end.

And don't forget to increase braking power to stop increased horsepower use and abuse.
 
Hey all!

So im thinking of grabbing the stroker kit from 440source and im wondering what/if anything needs to be done to the front/rear suspension and transmission if we turn the 400 into the 451 and what advice you all might have when it comes to suspension work for the 451 if it needs to be done at all.

If the car came with the 400, you dont need to do anything.

Brakes and suspension are common upgrades out of general principle, but not need.
 
It sure saves money if all you do is install a bigger, more powerful engine but you won't get the most out of it without upgrading other areas.
Brakes, man.
3 or more years ago, a video was making the rounds on the internet. A guy with a pro street 64 Mercury Comet was out on a drive with a guy that was interviewing him for a YouTube car related channel. The guy had undersized brakes for the power the engine was making. Unfortunately, he had a sticky throttle so he was riding the brake pedal..... that heated the brakes quickly. The idiot kept driving the car despite riding the brakes to keep the car from running away. He ended up ramming into some innocent motorist but somehow avoided killing anyone.
I am not a person obsessed with safety but I am aware of the need for brakes that match the increased power.
When I had my engine out in 2022, I upgraded the brakes. The car stops better now than it ever has.
 
That's a pretty extreme example. We're talking about a regular car
 
If it was an automatic, the only one fitted to the big block was a 727.
The LA series small blocks could have had a 904 or a 727.
I don't mean to come across as a worrier. I'm not one to recite the safety handbook but when it comes to doubling the power of a car, I like to make sure the car can respond well with it. I'm a big fan of improved handling and braking anyway but when the power levels are increased, those changes not only make the car easier to handle, it is a lot more fun too.
The classics can be made to stop and handle quite well. We get used to how our late model stuff drives and handles. We can make our classics so much better than they were when new.
 
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