400M to 429 questions

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Oct 16, 2002 | 05:49 PM

BBF429

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From: Metamora USA

400M to 429 questions

I built a 429 and am almost ready to swap out the 400M. I am wondering what torque converter you would suggest? It is in 1979 F-250 4x4 with a c6 transmission. I should be making 450+ horsepower. Also what does the different rpm stall speed change. What is the stock stall speed? I already have the L&L motor motor mounts, what about a flywheel? Is that something I would need. any info would help a lot! Thanks!

Oct 16, 2002 | 07:59 PM

FORDNUTTZ

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400M to 429 questions

you will need a flex plate and a block to trans plate

all 429's are enternal balance so you will have to have a enternal balance flex plate

Oct 16, 2002 | 08:14 PM

qtrmiler

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400M to 429 questions

Huh.... that's weird. My 29's aren't externally balanced.... Mmmmmm. The 400M, 429, & 460 share the same block plate, 460's are so interchangable a FE flywheel will fit.

Oct 16, 2002 | 08:52 PM

phantom429

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From: British Columbia

400M to 429 questions

All 429's are internally balanced, so all you need is a 429/460 flex plate, bellhousing and plate are the same for 429/460. As far as converters go you need to figure out what you use the truck for. A higher stall may mean better launch, and power, but the trade off is increased tranny operating temperatures, higher cruise RPM,s and increased fuel consumption.

I would personally go for a 2500 stall, I think stock is like 1600 or 2000 or something like that.

Nick from the frozen north
1974 F-250 4X4
soon to be 429
dana 60 front and rear

Oct 16, 2002 | 09:34 PM

gray79f250

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From: lake ariel usa

400M to 429 questions

Yes an internal balance 460 flexplate or any origional 429 flexplate. If you used a good quality cam the manufacturer should give a recommended stall speed and gear ratio. I would say not much more than 2500rpm. Most of these engines making 400-450hp hit there highest peak torque around 1500-1800 rpms if built for a truck in my best opinion.

Oct 18, 2002 | 07:45 PM

JMR

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From: DOG BOX

400M to 429 questions

> bellhousing and plate are the same for
>429/460.
hi all,

I am in the process of swapping in a 429 into a 71 f-250 4x4.
I bought a bell housing from a 460 about a year ago and it came with a block-to-bell plate, but the plate will not fit over the crank for some reason.......anybody have any idea why? It is big enough from
11o'clock position to 2o'clock position then it cuts down into a smaller hole......I wonder if I could take the plasma cutter and just continue the hole clear around? thanks , john

Oct 18, 2002 | 08:02 PM

georgedavila

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From: Nevada

400M to 429 questions

Torque converters - As phantom429 stated, it depends on your application. When living in deep snow country with bad spring mud, I ran T/Cs of 800-1000rpm with engines similar to yours. I couldn't spin the tires on dry pavement, but it would walk a horse trailer up a snow covered logging road at off-idle through 2500rpms like a diesel, tow big logs out of the woods or pull a house off the foundation without losing traction. In desert sand and shallow mud, I've found that higher rpms and a higher stall speed work better. If you're a racer, you want the converter to lock up when you're into the lower end of the torque band of your cam. Getting the usable torque band of your cam to the ground with minimum loss of traction is the name of the game.