I am rebuilding a b16a. I am going to replace the stock internals with forged pistons and rods. I would like to add turbo at some point, but I dont know how long it will take me to get it together. My question is about compression. I know that a lower comp. ratio is better for turbo, but I dont want to run a low compression for 6 months to a year while I am gathering parts. I work slow that is why I am guessing it will take that long. Would running 10.5:1 pistons be a bad idea? Can I later change the head gasket and lower the compression, or is that not very reliable? Any advice would be greatly appreciated.

 

I don't understand why you don't hold off installing the lower compression pistons till you're ready to add the turbo? Do you need the new stuff to get the thing back on the road?

 

It doesn't have to be low compression to boost it. I'm running a 10.5:1 gsr and it's going to be seeing a lot of boost this year. It's in the tune and grade of fuel that matters. Guys boost higher comp ratios than that. Think about bikes!! You'll be fine w/ 10.5:1. Don't worry about it.

 

I am just asking because I want to build the engine and drive it for a while before I add boost. The car is running fine with the stock d15 that is in it now. Basically I want to finish the engine build and make sure I can do that right before I start getting into turbo. This is my first rebuild and I dont want to over do it. I would like to drive an NA engine that I built (with good performance) before I explore the realm of turbo. I may like what I get and decide not to boost this engine. That is why I would rather run a higher comp. piston from the beginning. With 10.5:1 and boost would I have to use racing fuel? I know that the tune will determine a lot in regards to what fuel I can use, but I dont want to have to buy race fuel for it.

 

This is a smart way to go about building your motor. 10.5 is not a super high compression but it is on the high side for a boosted set up. Your looking at forged internals though so its safer then running stock internals in the long run. With that compression you can do lots of things and make good torque but you limit the ultimate amount of boost you can safely push also. Detonation will be your only enemy but tuning as with ne built is KEY. A good tune keeps all motors happy!!! Just remember wat your ultimate goal for your build is and stick to it. Nobody likes to build a motor twice so make sure you build it right and to your liking the first time...

 

thanx for the advice.

 

Just put low compresion pistons and drive it like this. I drove on low comprecion pistons for like 2 years before I put turbo. Its gonna run just fine, you won't even notice it.

 

normal comp.on a b16 is 10.2.1

 

the jdm b16a is 10.6:1.

 

sorry man the
b16a's in the sir's had 10.2 then in the sirII's it had 10.4. almost all b16's had a 10.2 except the sirII with 10.4 and the b16a4 with a 10.4 and also the
b16b with 11.0:1 none of them came with 10.6
actually the on b-series engine with a 10.6:1 is the b18c5 from the dc2 type-r integra