I fixed it! (sort of)

"The Swedish Bandit" (swedishbandit)
10/01/2018 at 14:45 • Filed to: c10, bbc, truck

Remember way back when, when I said that I blew the tranny in my truck and were going to try rebuilding it instead? !!!error: Indecipherable SUB-paragraph formatting!!!

Well other things happened and I realized I would never get around to it. But on the other hand I didn’t want to pay someone else to rebuild the trans either as that would have been very expensive.

So what do you do? You upgrade and go from a 4L60E to a 4L80E of course!

Small problem was (or big) that i came with an optional car as well, a 1999 Chevy 3500 Express.

No big deal though!, as after one weekend in my dads garage we got the powertrain free from the van.

And as an added bonus this tranny was also bolted to a gen 6 454 which should be a big upgrade from the 305 that sits in the truck right now.

Question is though, how much do I need to modify on the truck to get all of this to fit? Anyone ever done anything similar? Main concerns right now is will the old smallblock mounts work?, and how much of the electronics on the 454 can I scrap? I’d like to keep only the bare minimum.

DISCUSSION (11)

MM54 > The Swedish Bandit
10/01/2018 at 14:50

If you’re going to carb with that 454, most of the electronics can go, but you’ll still need ignition stuff / the distributor. As for fitting it in the truck, I doubt the old mounts will work, but you should be able to buy mounts for the swap; not exactly unheard of.

Definitely a step up from the 305!

The Swedish Bandit > MM54
10/01/2018 at 14:55

I’m thinking of going with intake, carb and new cam which should push it from 300 to around 450 hp. If I can keep the ignition that’s a plus since it’s pretty compact right now which will be good for later on. There also is the problem with the trans being electronically controlled so I guess I still need all of that too.

MM54 > The Swedish Bandit
10/01/2018 at 15:01

I don’t have any first-hand experience with them, but standalone transmission controllers are a pretty common thing, especially for a 4L80

MoCamino > The Swedish Bandit
10/01/2018 at 15:07

That thing will be a beast with a 454 in it. You’ll definitely need motor mounts, and I’m fairly certain you’ll need a transmission cross member. Better plan on heavier springs for your front suspension as well. There should be plenty of room in the engine bay for it, though.

The Swedish Bandit > MoCamino
10/01/2018 at 15:23

Yeah, I’ll yank out the 305 and lift this in fairly soon too see how far off I am at the moment. I saw that there does exist premade bbc mounts for this truck but after reading some reviews it seems like they’re a poor fit and need a ton of modification to work https://www.summitracing.com/int/parts/clp-6372mp-bm

I’m betting on modifying the existing mounts and crossmember to make it all fit.

Demon-Xanth knows how to operate a street. > The Swedish Bandit
10/01/2018 at 15:38

https://www.summitracing.com/parts/clp-6372mp-bm/overview/year/1972/make/chevrolet/model/c10-pickup

The Swedish Bandit > MM54
10/01/2018 at 15:47

Do you know of any good ones (cheap)? The cheapest one I can find is from MSD and cost like $500...

The Swedish Bandit > Demon-Xanth knows how to operate a street.
10/01/2018 at 15:48

See my reply to MoCamino, apparently those mounts are junk.

MM54 > The Swedish Bandit
10/01/2018 at 15:54

Unfortunately, that I do not have an answer for. Any time I’ve put a different trans into a car than I took out, it was a manual.

The Swedish Bandit > MM54
10/01/2018 at 15:56

Lucky you! ;)

MoCamino > The Swedish Bandit
10/01/2018 at 23:19

I’ve never used these but they look like they would be better. https://www.brotherstrucks.com/68-71-STOCK-FRAME-MOUNTS-BIG-BLOCK/productinfo/BBFM071/