Well finally got my truck picked up from the shop (well actually Pops picked it up since im in NY and the truck in FL). I was told by the machine shop who installed my new built short block that the engine now displaces 5.8L instead of the old 5.4L. The block had to be machined again I guess and bored out, the explanation for the increased displacement? Anybody had this done? How much torque/power increase can I expect from this coupled with a the usual exhaust, 6lb pulley? The shop owner said he pretty much guarantees 450-500rwhp... By the way, it does have upgraded internals, manley connectin rods, new teflon coated pistons etc... but I'll see the spec sheet later tonight. Thanks!

 

Only if you have changed the blower, ported or otherwise, or if you did heads/cams will you be at 500. Usually a 6 lb. lower/ ported blower combo and supporting mods nets about 425 in the heat.

 

i think MMR claims 40 hp from just boring out their 4.6 block to 5.0, so i would guess you would see similar gains from the increase displacment.

 

No way an overbore will jump displacement to 5.8 liters. Your machine shop needs to brush up on math skills.
If ported heads and cams are installed the HP #s will be in line with your expectations.
Jim

 

the only 5.8l engines that I know of made for the Gen.2 are built by Dantes Modular Performance, he uses an aluminum block, bores and strokes the engine from 5.4 to a 5.8..

 

unless he sleeved your block there is no way to bore out the block to 5.8 liters. vt engines and several other motor builders have built sleeved big bore 5.4's, there just not advertised.

 

It is possible to bore and or stroke Modular 5.4's to increased displacements. We @ DMP specialize in custom engine builds and have built several large bore and stroker engines. The usual large bore displacements equal 358ci. while the strokers equal 351ci.

If it is true that your new engine is 351ci, and they installed Manley forged rods that just does not make sense. First I am unawre of Manley making a forged stroker rod. With the incresed side load on the rods and pistons you must install highest quality components possible. We will either install Crower billet rods, but recommend using our custom Titanium rods. The cost is quiet high but there is nothing like power from increased displacement on an already powerful forced induction setup... Stan

 

I take back the 5.8L...my dad misinformed me. I went and visited the builder and looked at the build sheet as well. It is only bored to .30 over which is only a small increase. Anyway im glad i got my truck back and it runs pretty good, I still need to get a good tune though. My main question to begin with was: what do you a/f ratio do your lightnings show while in steady gas cruise mode? Thanks

 

14.7

 

Sorry got one of my other threads confused about A/F.