Been trying to decide if the motor I have can handle some boost. Currently forged crank and rods, but hypereutectic pistons. Tall deck 8.0l block. Was thinking of getting larger chamber heads to drop cr fro 9.9 to 8.9 and running about 9psi of boost with procharger. Currently installed are l29 style 99cc chamber heads. Was going to change to a set of brodix ovals 119cc if doing the procharger. Don't think the price per gain is worth doing just the heads as the l29 style oval port seem to be a decent head. Stock configuration with l29 style heads show to be about 420hp and 530ftlb. Trying to decide if willing to make this motor a money pit or keep it stock and just install as is. Going in to a 97 k2500 suburban. Setting up to be more tow oriented. Wondering if anybody have any experience on this. Also there is a question on ring gap.

Stupidly sold my 91 v2500 that I really wanted to build the bbc for, so currently working on a 97 k2500 as next best thing for the price. Actually regretted and tried to buy back that 91 the same day but that obviously did not work out.

 

9 psi is relatively small, you should be ok, as long as you keep an eye on AFR
you HAVE to gap hyper pistons big with boost/no2/supercharged

 

That is what I was thinking, gap the rings and have a good tune. Other question is if staying with 9.9 compression ratio or get bigger chamber heads to lower the compression ratio. Really want to keep things reliable, so still not fully sure about those pistons.

 

I would stay with the higher compression. Makes a better driver out of boost. Just have to pull a little more timing under boost on pump gas. If its got l29 heads already and you want to upgrade I would look at the afr oval ports. They stack up there with the big rec port stuff for being like a 270 head.

 

Not familiar with the heads anymore but just do forged pistons and forget the heads. Then you're good with a PC no worries!

 

off the shelf heads will drop my compression ratio, so it actually costs more to keep the cr up around 9.5:1. Almost convinced my self to just go with forged pistons. Apparently this motor uses metric rods/pistons. To go with common forged pistons, rods have to be changed too. Just to get forged pistons going to run $2300 or so. Have to bore/hone, rods, pistons. Can't find any forged pistons to work with 4.270 bore (020 over) that the block has. There are pistons that fit existing rods, but around $850 for a set.

 

If the motor isn't installed yet, I would go ahead and put pistons in it. Cheaper to do it now that when you get a little happy and burn a piston. But it all comes down to how much you want to spend.

 

I decided if it sees boost, it needs different pistons. Either stock or build it correctly. Now, just to decide if I want to commit. Looking up to see what fuel pump set up I can get put together. Going in to 97 suburban

 

sold the original motor in question and started with another one. Pulled it apart and will be going to machine shop for sizing new pistons. Anybody want to buy good 8.1l 020 pistons, forged rods, and stock cam(ls firing order)? And also 99cc chamber l29 style heads?