BB 402 into 72 K20 Problems????

[w314speed]

Thinking about putting a BB 402 in to 72 K20. What problems will I get into??
What is the easy way!!!!!!!!

Thanks,

Dan

[Bishops Trucks]

This is what I just wrote to another member doing a similar swap.
You need the big block towers that bolt to the frame, bigblock radiator, bigblock fan shroud, You might need to upgrade your fuel line to 3/8. Is the motor stock? You might need to install heavier springs in the front. Make sure you get all the brackets and pulleys. I'm sure I left some things out but someone else will jump in and help you.

[1969k10stepside]

The distributor and valve covers will probably hit the firewall.Some dent the firewall,some add a body lift,some move the motor forward and the t-case crossmember the same amout to solve the issue but have to get custom drive shafts since the stocks one would be to short and too long.But,some people don't have a bit of issues.Valve cover type,and distributor type are factors.I believe you can use the regular small block 4wd motor crossmember.

[w314speed]

I am also considering installing a GearVendors overdrive unit that I have had for years. If I can use it with an adapter, I will. I originally bought for a TH400 Truck, adapting to the np205 may be more than an adapter.

[earl87gta]

there were no 4x4 72 BB trucks so you have to use the SB cross meber or an after market one. if 73 to 87 came with a BB you could also use a cross member from one of them.

[bdozeraz]

Use short valve covers and you may still have to bump out the fire wall. Use your small block motor mounts on the big block and it will drop right in. You can use the same fan shroud but you will have to cut it back an inch or two. Use a four core radiator. We did this exact same swap on my dad's 71 GMC along with a 700r4 which only required moving the transfercase back 2 inches. We used the advanced adapters short output shaft in the 700r4.