thinking about building a 427

by dade1989 Wed Dec 26, 2012 8:33 pm

Wuz up guys I've always wanted a 427 but they are too much $$$$$$$ so buying 1 is not a option. I was told it would be a lot cheaper to build 1 . So my question is... i Have a 400 could I use that to build a 427. If I can wat would I need to do to it. Thanks for any help

by Joe73 Wed Dec 26, 2012 8:41 pm

If the 400 block you have came out of a passenger car then it would be considered a small block. All 427's are big blocks. You can probably "stroke" the 400 but I dont know who would make the correct parts for it AND you run into the whole internally/externally balancing of the engine. 400's were externally balanced and all the other small blocks were internally balanced. Thats why you can swap too many parts from a 400 to another small block.

by dade1989 Wed Dec 26, 2012 8:47 pm

The 400 is the 1 that originally came in my Laguna

by 77mali Wed Dec 26, 2012 9:08 pm

400's have "siamese" bore holes. You can go 0.20-.030 over but that might be pushing it. What's the horse power goal? At one time Chevy had 327's that were pushing 350 HP. It has more to do with the heads/cam & crank versus just raw cubes, although a big block can push out serious numbers compared to a small block.

by Joe73 Wed Dec 26, 2012 9:14 pm

Yup, that would be a small block. It can be done, but I dont think its worth it with that block. And any heads you put on the 400 have to have "steam" holes drilled in them, unlike regular small blocks.

by dade1989 Thu Dec 27, 2012 12:23 am

I can't complain about the engine all it has is a manifold and Holly Carb and to the best of my knowledge everything else is stock and it has a decent amount of power. It lights the tires Up and gets side ways. I just want to get a lil more out of it.

by dragons_lair59 Thu Dec 27, 2012 12:45 am

best bet build a 406 (.030) with nice heads and intake aftermarket crank cause the 400 crank is known to be very weak when used for much more then street duty and you will have a nice motor

for 427
454 block with 396 crank

by dade1989 Thu Dec 27, 2012 12:55 am

dragons_lair59 wrote:best bet build a 406 (.030) with nice heads and intake aftermarket crank cause the 400 crank is known to be very weak when used for much more then street duty and you will have a nice motor

for 427
454 block with 396 crank

Wat crank should I use

by pila Thu Dec 27, 2012 1:00 am

I've been pounding my 400 ( 408) since the early 80s, with no real bad effects. It's +.040 over. Flat-top pistons with 350 rods, with stroker rod bolts, to clear the camshaft. Decked block, heads milled off some, and a port & polish job. Bigger valves, 2.05 intakes & 1.65 exhaust. Cam is a Comp 280 Mag, with Rhoads lifters, to maintain some vacuum at low RPM for brakes and heater controls etc. I have a tuned 750 Holley on it, with a trick kit etc, which runs very good. And it LIKES gas !
After having a lot of SB Chevys over the years, the 400 is king of the heap for street fun. It requires a good stout 350 transmission though. It ate two, until I built my own.

by dade1989 Thu Dec 27, 2012 1:19 am

pila wrote:I've been pounding my 400 ( 408) since the early 80s, with no real bad effects. It's +.040 over. Flat-top pistons with 350 rods, with stroker rod bolts, to clear the camshaft. Decked block, heads milled off some, and a port & polish job. Bigger valves, 2.05 intakes & 1.65 exhaust. Cam is a Comp 280 Mag, with Rhoads lifters, to maintain some vacuum at low RPM for brakes and heater controls etc. I have a tuned 750 Holley on it, with a trick kit etc, which runs very good. And it LIKES gas !
After having a lot of SB Chevys over the years, the 400 is king of the heap for street fun. It requires a good stout 350 transmission though. It ate two, until I built my own.

I have a 700 r transmission I think I should be good with that .... if u don't mind me asking more or less how much did u spend doing all that to your engine

by dragons_lair59 Thu Dec 27, 2012 8:09 am

i like scat cranks some like eagle but scat has budget minded cranks

by pila Thu Dec 27, 2012 3:25 pm

New cranks are a lot more affordable now, than a few years back.

by bagpipe71 Sat Dec 29, 2012 3:17 pm

Ls7 small block

by Brainstain Sat Dec 29, 2012 7:06 pm

^ There ya go. Got $6K for a used engine? On the subject though, a carbed LS1 or 5.3 would make plenty of HP and anything you'd do to a BB you can do to an LS and make just as much of not more power.

by dragons_lair59 Sat Dec 29, 2012 8:14 pm

But price of all the odds and ends plus the kit to install kit

by pila Sun Dec 30, 2012 6:21 am

My 400 wasn't too bad for money spent on rebuilding it. Machine shop prices are higher now than in the 80s & 90s, when I did a lot of engines.
I haven't looked into the LS engines yet, but the numbers I see on them are impressive for the size of the engines.

by Brainstain Sun Dec 30, 2012 8:12 am

A junk yard 5.3 can be had for $500 or so. MSD and Edelbrock make a kit that's just shy of $800 and gives you a timing box with all the wiring and the intake. Add in the easy route of $100 for engine mounts off ebay and youre basically done. I'm swapping a 6.0 EFI and a carbed LS1 right now. If you go used you can spend much less money on the swap parts and could probably buy a small cam also. I'm gonna be into my carbed Ls1 about 2K. It's got a 230/224 .585/.563 111 lsa cam and some .650 lift springs and should be in the neighborhood of 430-450 hp.

by pila Wed Jan 02, 2013 2:52 am

That's less money than building an older engine. And technology has come a long way since the early days.

by Sponsored content

thinking about building a 427

thinking about building a 427

Re: thinking about building a 427

.

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427

Re: thinking about building a 427