Its a Stock D16Z6 with about 95,000 miles on it.
I had read somewhere that the stock size is 75mm and that can be bored out to 79mm max. If I have it bored out I would only need to buy new pistons right? What would be the expected gains in doing this?

Long term goals for motor and car are a junkyard turbo setup. That will be a while though.

Thanks

 

You want to bore your stock sleeeves out to 79mm? Don't expect that to last very long with boost.

 

ok so its not a good idea then? I dont know too much about it thats why I'm asking.

 

You can go as far as .040 inches (1mm oversize) on stock sleeves but anything bigger than that is pushing it. Going anything over 2mm is definitely going to require re-sleeving the block. As for 79mm, I'm not even sure if there's enough physical space for a piston that big in a D-series block. There might be, but the sleeves are gonna cost a bundle.

As far as power gains, you'll be able to feel a 1mm overbore. The bigger you go, the higher your compression ratio goes, unless you put in dished pistons for a boost application.

 

Thank you, so 1mm is SAFE (important) and would provide gains right? Now if I do that do I need pistons that are 1mm larger?

 

you can easily get into b16 territory with a 1mm overbore, some headwork, pistons and a cam - plus, you'll have a bit more torque then a regular b16. I've argued about this many times before, but I know a nicely built and modded D16Z6 will walk any stock b16a - and why? because the D16Z6 has a much wider torque band starting way down low - the b16 just starts to kick in at around 4000 or so. We got about 142 whp and 135 ft/p torque out of a D16Z6 built out of the above recipe - no more, no less. Yeah, if you want to go all out and spend the money, go with a b18c for NA but if you want the best bang for your buck, build the D16Z6 - and yes, the stock rods will hold up ok for your application - you can always have a set of ls rods sized to fit your engine for about $200, but then you will have to rebalance everything. I have stock rods in mine and rev it up to 8000 without worry.

 

Ok, if I have it bored out 1mm is there anything else that I have to buy to fill in that extra 1mm of new space? (Have to meaning that if I dont get item X my engine will melt in 30 days)
Sorry if it sounds simple but I dont know too much about the process and cant find crap online.

Thanks

 

You will need new pistons and rings, as well as having the piston pins pressed in by a machine shop when you change them. Also do yourself a favor and get a set of ARP bolts for the rods and some studs for your head... they are fairly inexpensive and good insurance. If you're planning for turbo, get a set of forged low compression SRP pistons (8.5 - 9.0:1) and rings to handle the extra heat and pressure in the cylinders, otherwise stock pistons and rings for NA. Turbo also dictates looser ring gaps and a little more piston to wall clearance. Any competent engine builder can give you these details when Ur ready to build.

 

I'm not sure if the planned build is for turbo or NA, but in case it's NA, just in case it hasn't been said yet, I've determined pretty much beyond a doubt (based on various qualified opinions) that you can also run your overbored engine (1 mm on stock sleeves safely) up to 11:1 compression with no problems. Granted that may not be as quick as a turbo setup, but it would be much less expensive, easier to build and will still chew up and spit out any B16 on the road.

 

high comp is no problem with that overbore - turbos put more strain on the internals, even though you're running lower static compression than NA - it's the dynamic compression that counts. The only thing that's gonna wreck a sleeve with NA is detonation. You will get much better throttle response and more torque/power with 11:1 comp... you'll have to run premium gas all the time! The last D16 we built had about 11.2:1 on a 1mm overbore - it put a big smile on our faces when we first drove it! Just be sure to use a stock headgasket, they are so much better quality than the cheaper Fel-blow line that Autozone carries - I had many problems with these even on NA D16s.