slamgears

So here's some background: I'm building a 69 c10. Going with a boosted 4.8 or 5.3 with one main thing affecting my decision. Power.
I'm looking to make 650whp reliably on the stock bottom end. I know this has been done a TON on 5.3's so I knowo the 5.3 would handle it, but what about a 4.8? This a is a budget build, so going 4.8 would allow me to pick up way cheaper motors.
how much is too much for a street driven 4.8? Don't wanna be out driving somewhere with the family in the truck and pop a motor and have to deal with all that because I went 4.8.

JoeNova

All factors equal, the 4.8 will be stronger. Better rod/stroke ratio, more journal overlap on the crank, less side-loading which helps with piston/rod/block strength. Less low/mid torque helps keep parts alive even more.


The fact that it also makes less low/mid range torque helps with traction on the street. My buddies TT 4.8 makes 600whp and can hook on the street with good street tires. My 5.3 at 700whp will spin ET Pros from a 40 roll easily.

00pooterSS

iTrader: (40)

JoeNova nailed it.

Build your 4.8 man, it'll take it just as well if not better like said above.

A.R. Shale Targa

iTrader: (2)

True story. Thread over by post two
Solid "real world" advice by JN

slamgears

I like it when I can get a solid answer in less than a day hahaha I looked all over google and couldn't find one post to tell me if a 4.8 would handle 650 in a streetcar reliably, come on here and I get an answer in 20 minutes

A.R. Shale Targa

iTrader: (2)

read Hot Rod's "Big Bang Theory"....they made 1204 ponies with what they thought to be a 5.3 until tear down when they realized it was a 4.8
Trick Flow heads/cam and they opened up the ring gaps/put the OE rings back in with XXXXX miles; and rusty cylinders from sitting in the junk yard. They literally tried to blow it up and after 60 plus dyno pulls, they ran out of time and were blowing the spark plugs out at 30 pounds of boost

slamgears

Yeah that's actually where I got the idea from to go 4.8. I was like, if they can pull 1200 HP for 60+ pulls, surely I should be able to run 650 reliably on the street.
I can't decide how far to go with it. Plan is to just run pac 1218 valvesprings and just do the other cheap head stuff while i'm in there, and throw a cam in it, just set it up to handle boost well, but not sure if I wanna pull pistons and do rings.Thinking I should because I know if I don't i'm gonna slap it all in and have a bad ring.

A.R. Shale Targa

iTrader: (2)

If its a high mileage say over 100,000 or so, the rings should be good for 8-10 pounds of boost which could satisfy your power level. Most that boost twenty or more open them up a bunch