As the title says, I'm looking to destroke my 6.0 block using a 4.8 crank. I know I know....I've read over and over about how it's pointless and not worth it. But I'm thinking its a better route to go because of my LS swap situation. I have a 99 ranger extended cab 2wd, cab is stripped, a/c removed, and will be going manual steering, so it will be on the lighter side #3000ish. I'm doing caltracs in the back to help with traction. It will be mainly strip but will have the occasional street drive time.
The idea is since it's a smaller, lighter truck moving the torque to a bit later in the rpms with help with launching and not blowing the tires, and build a higher rpm motor to come on stronger later.
The build idea right now is to use my 6.0 block and 4.8 crank with the corresponding forged rod/piston. Shooting for 12.0:1 - 12.5:1 compression.
Aftermarket heads: possibly LS3 style,MAST 255cc, PRC 237 heads. Which ever I pick they will have the valve train to handle 7500rpm.
Custom spec'd cam and Use a short runner manifold to help airflow in the higher rpm and 1 7/8 headers with maybe 4 inch exhaust. And I can always add a little 100 or so shot if necessary.
Transmission will be either a th350 or 400.
Any ideas? Opinions?
Thank everyone!!

 

Dumb idea....ive spun 6.0s 7500 for shifts


The issue is unless you plan solid roller and spend big money on an actual valve train for 8000+ theres no advantage....Proper cam will determine rpm range

Also know of 400 cube motors spinning 7000+

 

Yea I would pick top end parts for the desired power range rather than removing cubes. The valvetrain parts needed to accomplish RPM that you would gain beyond what you can do with a 6.0 would be costly.

Keep the TQ. Shoot for a fairly high RPM engine and have at it.

 

I think I have still have a good crank from a 6.0 I can use. The destroking was just a idea because I'll still be getting good flowing aftermarket heads and intake regardless.

 

If youre going to be spending premium dollars on heads I would likely go with a top of the line 225-235cc cathedral head on something that is stock cubes. NA I would be a little concerned with valve shrouding on a rectangle head. Being boosted I was not as concerned with that on my build.

Now if you told me you had a budget I would say that some ported GMPP LS3 heads are best bang for the buck.

 

I mean if I find heads that perform decently over some 243s Ill jump on them and save some money lmao but I don't mind paying extra for higher end heads if the gains are there. I have under $1000 in the truck, block and current rear so I have room to spend extra in places. Thanks guys for the input!

 

Trick flow as cast 220s are damn near impossible to beat

 

George do you prefer them over their CNC 225's?

 

From everything ive read and saw the 220s out of box come up a smidge shy but the 220s can be ported heavily and put up insane numbers...its the perferred head by many....they keep the velocity up there

Saw tooley and others praising them over the years

Maybe one day ill have my 220s ported but for out of box they flow alot now

 

i will check them out some more! i seen the price and even if i get the 220s and get them ported ill still be cheaper than some out of the box high $ heads.